ALBERT

Description: Non-native wood-boring beetles (Coleoptera) represent one of the most commonly intercepted groups of insects at ports worldwide. The development of early detection methods is a crucial step when implementing rapid response programs so that non-native wood-boring beetles can be quickly detected and a timely action plan can be produced. However, due to the limited resources often available for early detection, it is important to identify the best locations where to concentrate surveillance efforts. The aim of this study was to investigate the role of wood waste landfills in the early detection of non-native wood-boring beetles. From June to September 2013, insects were collected in multi-funnel traps baited with a multi-lure blend (α-pinene, ethanol, ipsdienol, ipsenol, and methyl-butenol) at the main port and a nearby wood waste landfill in 12 Italian towns. Overall, 74 species of wood-boring beetles (Buprestidae, Cerambycidae, and Scolytinae) were trapped, among which eight were non-native to Italy. We found that species richness and species abundance of both non-native and native beetles were significantly higher in the wood waste landfill than in the ports. However, the non-native and native communities were similar in the two environments. The main conclusion emerging from this study is that wood waste landfills, given their similarity with ports of entry, should be considered when surveying for non-native wood-boring beetles. Therefore, within the framework of creating long-term monitoring programs that include both coastal and continental areas, both ports and wood waste landfills should be monitored to improve the probability for early detection of non-native species.

Description: The efficacy of spot-spray application of conidia of Metarhizium anisopliae (Metsch.) Sorok. conidia formulated in an emulsifiable extract of Calpurnia aurea (Ait.) Benth in attracting and infecting Rhipicephalus appendiculatus Neumann, 1901 ticks was evaluated in semi-field experiments. Formulation was applied on a 900-cm² spot and ticks released from various distances. Attracted ticks were individually placed in glass vials to determine the number of M. anisopliae conidia picked by a single tick. Infected ticks were either transferred in glass vials or maintained in the laboratory until death or exposed to rabbits in order to investigate the effects of fungal infection on feeding and potential reproduction parameters. Data showed that individual ticks picked between 3.2 and 4.1 × 10 5 conidia. Mortality of 83 % was observed among ticks maintained in the laboratory conditions. The engorgement period of fungus-infected ticks significantly increased by 16 % compared to the control. A significant reduction ( P  〈 0.0001) was recorded in body weight, egg-mass and egg hatchability from fungus-infected females. It is therefore possible to use M. anisopliae formulated in C. aurea extract for an integrated pest management approach. This study showed that conidia of M. anisopliae formulated in C. aurea extract are effective in attracting, infecting and causing mortalities of R. appendiculatus ticks. Moreover, the reproduction performance of fungus-infected females was significantly reduced.

Description: The South American tomato leafminer Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is a devastating pest in tomato crops. After having spread rapidly in the Mediterranean area since its first detection in 2006, it has recently become established in greenhouses in Western Europe. It was assumed that the low temperatures commonly associated with the winters in this area would prevent this exotic species from successful overwintering. However, the observed presence of T. absoluta at the start of the growing season in Belgium sparked a study on its potential to overwinter in Western Europe. In this study, the insect’s cold hardiness and overwintering potential was assessed by determining: (1) the supercooling point (SCP) of larvae, pupae, and adults, (2) the lower lethal time (LT) for these stages at 0 and 5 °C, and (3) the reproductive diapause incidence, as indicated by the reproductive performance of females reared at two temperatures (18 and 25 °C) and two photoperiods [16:8 and 8:16 (L:D) h]. The mean SCP recorded for pupae (−16.7 °C) was significantly higher than for adults (−17.8 °C) and larvae (−18.2 °C). Based on estimates of the LT adults demonstrated better cold hardiness than larvae and pupae at both 0 and 5 °C with the median LT of adults averaging 17.9 and 27.2 days, respectively. No reproductive diapause was observed under the tested regimes. The results of this study indicate that T. absoluta is likely to successfully overwinter between two successive tomato crops in commercial greenhouses in Western Europe.

Description: As very little is known about the impact of cold pre-treatments on insecticidal toxicity to the surviving stored-product insects, we examined the effects of cooling (−5 °C) on the toxicity of five contact insecticides to Sitophilus granarius adults from three populations (laboratory, field and selected). We determined: (a) weevil lethal time after exposure to −5 °C, (b) the effects of two cold pre-treatments (LT 20 and LT 50 —lethal time for 20 and 50 % of exposed adults) on 24 and 72 h recovery rates of laboratory adults after exposure to five insecticides and (c) deltamethrin, dichlorvos and malathion toxicity to two weevil populations with altered insecticide susceptibility after exposure to the LT 20 and LT 50 pre-treatments. The tested S. granarius populations showed no significant differences in their susceptibility to cooling. All insecticides except dichlorvos were more toxic to the laboratory weevils after 24 h than after 72 h recovery from the LT 20 pre-treatment. Dichlorvos and deltamethrin were more toxic to the other two populations after 72 h of recovery. Comparing the effects of cold pre-treatment and non-treatment on the laboratory strain, no significant increase in the toxicity of insecticides was detected, while only deltamethrin was significantly more toxic to the field and selected populations recovering for 24 h (12.1 and 11.0 times, respectively) and 72 h (6.9 and 36.6 times) from the LT 20 pre-treatment. In conclusion, only the shorter of the two cold pre-treatments was found effective in terms of increasing the insecticidal toxicity, especially against the populations with altered susceptibility to insecticides.

Description: Maintaining the numbers of wood mice and common voles at an acceptable economic level, especially during years of massive outbreaks, is a major challenge in plant protection. Efforts to reduce the negative effects of rodenticides on the environment, to improve the integrated pest control system, and to minimize risks for human and animal health require investigation of the potentials of cellulose, as a natural product, and sodium selenite as rodenticides. The present study was conducted to determine the sensitivity of these rodent species to bromadiolone (a.i. 0.005 %), sodium selenite (a.i. 0.1 and 0.05 %), and cellulose (a.i. 45 %) baits. All experiments were done using no-choice and choice feeding trials. A low acceptance of cellulose baits was found in the choice feeding trial, and the time of first deaths indicate that stress and hunger increase the death rate in both species. The taste had a negative impact on the acceptability of baits containing sodium selenite. Low bait acceptance of cellulose and sodium selenite resulted in lower mortality of both species. The acquired results indicate that bromadiolone remains a more effective solution than cellulose and sodium selenite for control of wood mice and common voles.

Description: The worldwide presence of feral pigeons Columba livia domestica in urban habitats presents potential public health hazards from pathogens and parasites, and droppings can lead to damage to buildings. A variety of lethal and non-lethal chemical repellents, visual, sonic or mechanic measures are available to deter pigeons, but they are not always applicable or effective. Ultrasonic devices are one of the available possibilities with the advantage of being inaudible to humans and more or less harmless to animals. However, their utility is questionable, because the upper limit of frequencies heard by pigeons reported is well below that of ultrasound. We tested whether a commercially used ultrasound deterrent system has an effect on the behaviour of free-living, as well as caged feral pigeons and assessed whether ultrasound has a physiological effect, i.e. whether it can activate the hypothalamo-pituitary-adrenal-axis (HPA-axis) known to trigger flight behaviour. Our experimental tests did neither show any effect on the behaviour and the HPA-axis of the caged pigeons nor any deterring effect on the free-living pigeons. A habituation effect could not be detected. We therefore, conclude that ultrasound does not deter feral pigeons.

Description: Sunn pests are responsible for serious kernel damage on wheat ( Triticum aestivum L., Poaceae), affecting bread-making quality from their feeding at the late milk-ripe stage. In this study the toxicity of three pyrethroids usually applied to this crop (λ-cyhalothrin, α-cypermethrin, τ-fluvalinate) was evaluated on two bug species, the wheat bug Eurygaster maura (L.) and the green stink bug Nezara viridula (L.) in both laboratory and semi-field conditions, to implement an effective and sustainable control strategy. Laboratory trials showed small differences between the insecticides, whereas field cage trials gave more information on toxicity and persistence of the three pyrethroids. The most toxic and with good persistence on plants was α-cypermethrin, followed by λ-cyhalothrin, which had an intermediate persistence. By contrast, τ-fluvalinate showed a high persistence on plants, but seemed unsuited for wheat bug control because of its low toxicity, as clearly demonstrated in both laboratory and semi-field trials. The results provide clear information on the application strategy of the tested pyrethroids. In this context, α-cypermethrin proved to be the most promising active ingredient for wheat bug control, particularly for early application of the insecticide in a mixture with a fungicide at the wheat heading stage, eliminating the need for a separate additional treatment by the farmer.

Description: This study sought to provide relevant information for developing effective programs to manage Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) resistance to insecticides by quantifying and describing the interactions between cotton Bt and Podisus nigrispinus (Dallas) (Heteroptera; Pentatomidae) in the management of lambda-cyhalothrin resistance in S. frugiperda fed Bt cotton leaves expressing Cry1Ac (Bollgard, Monsanto, St Louis, MO, USA). These effects were assayed by studying functional responses. Third instar S. frugiperda larvae were used for the following treatments: strains resistant (1) or susceptible (2) to lambda-cyhalothrin fed Bollgard cotton leaves and strains resistant (3) or susceptible (4) to lambda-cyhalothrin fed non-Bt cotton leaves. The predatory behavior of P. nigrispinus females was best represented by a sigmoid curve. The type of P. nigrisinus functional response was not affected by the cotton cultivar or S. frugiperda strain used in the trials. P. nigrispinus females invested a greater amount of handling time ( T h ) in S. frugiperda larvae that were suseptible to insecticides and fed non-Bt cotton ( T h  = 1.72 h) compared to those from the insecticide-resistant strain fed with Bt cotton ( T h  = 1.23 h) or even compared to those that were lambda-cyhalothrin resistant and fed Bt ( T h  = 1.17 h) or non-Bt cotton ( T h  = 1.17 h). The results in the present study can be applied in the development of management programs targeting S. frugiperda resistance to pyrethroid lambda-cyhalothrin. The integration of Bt cotton concurrent with biological control by the Asopinae P. nigrispinus is important for successfully managing S. frugiperda resistance to lambda-cyhalothrin.

Description: The soil dwelling larvae of the wheat bulb fly ( Delia coarctata , Fallén) can cause damage to a number of cereal crops. Monitoring of the oviposition of this pest is important to allow forecasts of larval attack after the overwintering period, allowing suitable management practices to be implemented. However, little is known about the population dynamics of wheat bulb fly, both spatially and through time. Analysis of the spatial dependence of oviposition was conducted, allowing the construction of detailed contour or scale-sized dot maps of oviposition in the sampled fields. The population estimate obtained by the sample for estimate technique, used to test spatial dependence, was compared to the traditional wheat bulb fly sample for decision-making methodology. Further to this, the peak period of egg population density was established for Scotland. Spatial dependence was observed in 50 % of fields assessed, while field monitoring of egg population densities using the traditional single-line transect pattern were found to vary greatly from the mean density collected from a more intensive 50 by 50 m sampling grid. These findings suggest that the single-line transect sampling pattern is not robust enough when estimating the patchy egg distribution observed in the sampled fields. The peak period of egg population density, observed over three successive seasons, was found to be in late August, with population estimates taken prior to, or after this period showing a marked reduction in the observed maximum population. The results highlight the difficulty of obtaining accurate population density estimates for aggregated pest species and indicate that monitoring programmes, that have been implemented without thorough investigation into pest population dynamics, can lead to the execution of incorrect management strategies.

Description: The invasive Halyomorpha halys was accidentally introduced into Switzerland around 2004 and has recently established in the neighbouring countries of France and Italy. To better understand the population dynamics of this pest in Europe, the phenology, reproductive biology and temperature requirements of Swiss H. halys populations were investigated. Overwintered adults became active in April, but peak oviposition was not observed before early July. Individual females laid on average 79 eggs (maximum of 160). The oviposition period lasted from mid-June to end of September. Eggs laid in August and September did not result in offspring due to the low temperatures in autumn. Under natural fluctuating temperatures, development from egg to adult lasted between 60 and 131 days. The first new generation of adults did not occur before mid-August when the photoperiod was already below 15 h, which likely initiated diapause and suppressed the reproductive activity of new generation adults. Under controlled conditions of 20, 25 and 30 °C, Swiss H. halys populations developed within 75.8, 42.3 and 33.2 days from egg to adult, respectively. No development was possible at or below 15 and at or above 35 °C. The number of degree days required for completion of development from egg to adult was 588.24 DD. Under semi-natural conditions, total mortality of Swiss H. halys populations was 86.7 % with a net reproductive rate of 5.69, indicating growing populations. In Switzerland, H. halys is univoltine, but if it continues to spread into the Mediterranean area two generations per year could be expected.

Description: Thaumastocoris peregrinus is a sap-sucking insect that infests non-native Eucalyptus plantations in Africa, New Zealand, South America and parts of Southern Europe, in addition to street trees in parts of its native range of Australia. In South Africa, pronounced fluctuations in the population densities have been observed. To characterise spatiotemporal variability in T. peregrinus abundance and the factors that might influence it, we monitored adult population densities at six sites in the main eucalypt growing regions of South Africa. At each site, twenty yellow sticky traps were monitored weekly for 30 months, together with climatic data. We also characterised the influence of temperature on growth and survival experimentally and used this to model how temperature may influence population dynamics. T. peregrinus was present throughout the year at all sites, with annual site-specific peaks in abundance. Peaks occurred during autumn (February–April) for the Pretoria site, summer (November–January) for the Zululand site and spring (August–October) for the Tzaneen, Sabie and Piet Retief monitoring sites. Temperature (both experimental and field-collected), humidity and rainfall were mostly weakly, or not at all, associated with population fluctuations. It is clear that a complex interaction of these and other factors (e.g. host quality) influence population fluctuations in an annual, site specific cycle. The results obtained not only provide insights into the biology of T. peregrinus , but will also be important for future planning of monitoring and control programs using semiochemicals, chemical insecticides or biological control agents.

Description: The effectiveness of bees as vectors for microbial biological control agents has been demonstrated in greenhouses and some small-acreage crops. Less is known about the viability of this tactic for other cropping systems, or the effects of outfitting hives with dispensers on the bees. Experiments conducted in lowbush blueberry ( Vaccinium angustifolium ) fields indicated that home-made wooden, Koppert, and Enviroquest dispensers had no significant effects on foraging behavior or pollen loads of the bumble bee Bombus impatiens , but the presence of a dispenser did reduce the rate of workers exiting hives. Following exit of bees from dispensers, no difference was found in the quantity of the microbial agent Clonostachys rosea applied to the bees or blossoms, and distribution of product in the field was not influenced by dispenser design or distance from hives. However, the prevalence of the pathogen Botrytis cinerea in blossoms from cages that contained hives with dispensers with C. rosea was significantly less (10–20 %) than blossom infection in control plots, despite unseasonably inclement conditions and restricted foraging. These results suggest that C. rosea can be effectively delivered by commercial bumble bees for prevention of B. cinerea infection in V. angustifolium , but the efficacy of the technique will be limited during periods of poor weather that often occur in regions where lowbush blueberries are grown. Some technical issues with dispensers and commercial B. impatiens hives also need to be addressed before widespread use can be expected within commercial lowbush blueberry production.

Description: Essential oils are being investigated as potential herbicides or to provide leads to new environmentally and socially acceptable herbicides. Novel hydroxy and ester derivatives of 1,8-cineole and 1,4-cineole were synthesised, by chemical and biological methods, and have shown pre-emergence herbicidal activity against annual ryegrass and radish. Effects on post-emergence activity of these derivatives, as well as 1,8-cineole, eucalyptus oil and the carboxylic acids from which the esters were derived, against annual ryegrass and radish, are reported here. Results suggest that reduced root and shoot growth observed in pre-emergence herbicidal bioassays were due to post-emergence activity rather than delayed germination. All tested substances had a dose-dependent, post-emergence herbicidal activity against annual ryegrass and radish with many derivatives showing improved activity relative to 1,8-cineole and high-cineole eucalyptus oil. However, results do not support the postulate that cineole esters would be more active than their respective carboxylic acid and the hydroxy cineole. Phytotoxicity of ester derivatives may be due to metabolic cleavage of the esters to the hydroxy cineole and carboxylic acid within the plant.

Description: The genus Spodoptera contains some of the most destructive crop pests in the world owing to the worldwide distribution of the different species and their wide host ranges. Uses of semiochemicals for insect control have been recently reviewed, but strategies developed specifically against Spodoptera species are scarce. In this review, we present an updated account of the semiochemicals and other natural product-based approaches to monitor and control the most damaging Spodoptera spp. In general, successful control of Spodoptera littoralis , S. frugiperda , S. litura , and S. exigua have been reported through mass trapping, mating disruption, and attract-and-kill methods. An updated survey of the pheromone components of these species and an outlook of future perspectives against these pests are also outlined.

Description: Spinetoram and spinosad have been evaluated against certain stored-product insect pests with success but there are no data available on the comparison of the efficacy of these two novel compounds in stored grains. Thus, laboratory bioassays were conducted to compare spinetoram and spinosad as grain protectants against Prostephanus truncatus (Horn) (Coleoptera: Bostrychidae) adults, Rhyzopertha dominica (F.) (Coleoptera: Bostrychidae) adults, Sitophilus oryzae (L.) (Coleoptera: Curculionidae) adults, and Tribolium confusum Jacquelin du Val (Coleoptera: Tenebrionidae) adults and larvae. Factors such as treatment (1 ppm spinetoram, 1 ppm spinosad, 0.1 ppm spinetoram + 0.9 ppm spinosad, 0.5 ppm spinetoram + 0.5 ppm spinosad, and 0.9 ppm spinetoram + 0.1 ppm spinosad), exposure interval (1, 2, 7, and 14 days), temperature (20, 25, and 30 °C), and commodity (barley, maize, rye, and wheat) were evaluated. Progeny production was assessed after 60 days of exposure. Concerning temperatures, for P. truncatus adults, after 14 days of exposure, all adults were dead in treatments except of the case of spinosad alone at 20 °C. Offspring emergence was completely suppressed in all treatments at 20 and 25 °C. For R. dominica adults, after 7 days of exposure, the overall mortality ranged from 92.8 to 100 %. After 14 days of exposure, all adults were dead in all treatments of the combined use of spinetoram and spinosad at 25 and 30 °C. Progeny production was completely suppressed in all treatments at 30 °C. For S. oryzae adults, after 7 days of exposure, all S. oryzae were died at 25 and 30 °C in all treatments except in the case of spinosad alone. Offspring emergence was very low in all treatments and temperatures except in the case of spinosad alone at 30 °C. For T. confusum adults, after 1, 2, and 7 days of exposure, the overall mortality was low in all treatments and temperatures. Concerning commodities, for R. dominica adults, after 7 and 14 days of exposure, the overall mortality was 〉97 %. Offspring emergence was very low in all commodities. For S. oryzae adults, after 7 and 14 days of exposure, the overall mortality was increased exceeding 91 % except in the case of spinosad alone 7 days after exposure in barley. Progeny production was high in barley and rye in all treatments. For T. confusum adults, after 7 and 14 days, the overall mortality was low in barley, rye, and wheat. No offspring emergence was recorded in all treatments and commodities. For T. confusum larvae, after 14 days of exposure mortality was further increased, but did not reach 100 % for any of the combinations tested. The results of the present study suggest that the simultaneous application of spinetoram and spinosad was generally equally effective with the use of either spinosad or spinetoram alone. Furthermore, the increase of dose of either compound resulted in the same mortality levels. Thus, no benefits were achieved when spinetoram and spinosad were used simultaneously on grains, regardless of the proportion of each ingredient. These issues should be seriously considered when control measures against stored-product insects are designed.

Description: The sweet potato whitefly, Bemisia tabaci Gennadius biotype B (Hemiptera: Aleyrodidae), causes high economic losses in vegetables, beans, soybeans, peanuts, cotton, and several ornamental plants. Repeated spray applications of synthetic pesticides has led B. tabaci to develop resistance to numerous conventional insecticides, besides polluting the environment. In this work, we investigated the bioactivity of the essential oil of Pelargonium graveolens L’Her (Geraniaceae) (PG-EO) and some related monoterpenes against the sweet potato whitefly Bemisia tabaci Gennadius biotype B (Homoptera: Aleyrodidae) in tomato. This oil significantly reduced the number of B. tabaci adults on tomato leaflets. The deterrence experiments showed similar results for PG-EO, geraniol, and citronellol; however, citronellol was more effective than PG-EO. In fumigation tests, the essential oil of P. graveolens caused 100 % mortality of adults of B. tabaci biotype B at concentrations from 0.5 μL L −1 in air. The vapor toxicity of geraniol, linalool, and citronellol, the main chemical constituents of the essential oil of P. graveolens (PG-EO), was similar to that of PG-EO. These results suggest that PG-EO and its related monoterpenes are potentially applicable to develop effective natural product-based pest-management compounds.

Description: The western corn rootworm ( Diabrotica virgifera virgifera ; Coleoptera: Chrysomelidae) is a major maize pest in North America and Europe. For developing population models to better understand this key pest, survival rates need to be known. In contrast to the reported field survival of eggs, the three larval instars, and pupae, the survival of the adults had not been assessed under field conditions. Weekly survival of adults was studied in large walk-in gauze cages in two fields in Hungary between 2009 and 2011. Each cage contained a combination of maize with two out of nine other crops. The number of adult beetles rapidly decreased with time following an exponential-like survivorship curve, with a weekly mortality varying between 31 and 61 %. This is in contrast to laboratory experiments, where populations decreased with time following a linear-like curve. The average lifespan was only 19 days with a maximum of 84 days. After 14 days, 55 % of adults had died, thus, having had no chance to lay eggs because of the pre-oviposition period required. Maize appeared to be the most appropriate crop for survival. Combining maize with other crops that could serve as alternative food did not enhance survivorship, and many combinations were in fact disadvantageous. Crop and weed coverage played a minor role in influencing survival, and only few weeds appeared slightly advantageous. It is argued that the role of alternative food sources for D. v. virgifera adults might be overestimated. Survivorship equations are suggested to support modelling of population dynamics of this pest and to support timing of direct control measures against the adults to prevent their egg laying and therefore damage to maize roots the following year.

Description: Brown marmorated stink bug, Halyomorpha halys (Stål) is a highly destructive invasive pest of annual and perennial crops in the eastern United States and is an increasing threat to agriculture in the Pacific Northwest. Flight mills were used to examine flight capacity of H. halys in order to better understand its invasive characteristics. Specifically, we examined generational, sexual, and phenotypical effects on flight distance, frequency, velocity, and diel flight patterns of field-collected H. halys from two seasons. There was a clear dichotomy in total flight distance for insects that flew 5 km or less and those that flew more than 5 km in 24 h. The tendency for long distance flight of H. halys changed over the course of a given season, peaking at the end of the growing season. Summer generation H. halys flew farther and faster than overwintered adults, but not as frequently. Males and females had similar numbers of flights, but females went farther. Pre-flight weight of insects was correlated flight activity of adults in terms of speed, frequency, and distance. Overwintered H. halys lost a greater proportion of their pre-flight body weight during the assay than did the summer generation adults. Despite many limitations extrapolating flight mill data to the field, this study nonetheless provided evidence that H. halys has the capacity for long distance flight, particularly in the summer generation. The nutritional status and fat reserves of overwintered versus summer generation adults are discussed as potential explanations for the flight patterns found in this study.

Description: Tephritidae are an enormous threat to fruit and vegetable production throughout the world, causing both quantitative and qualitative losses. Investigating mating sequences could help to unravel mate choice dynamics, adding useful information to improve behaviour-based control strategies. We review current knowledge about sexual communication and related behaviours in Tephritidae, with a focus on six key agricultural pests: Anastrepha ludens , Bactrocera cucurbitae , Bactrocera dorsalis , Bactrocera oleae , Ceratitis capitata and Rhagoletis pomonella . We examine features and the role of male–male combat in lekking sites, cues affecting mating dynamics, and some fitness-promoting female behaviours that occur at oviposition sites [the use of oviposition marking pheromones (OMPs) and female–female fights for single oviposition sites]. We outline future perspectives and potential contributions of knowledge about sexual communication to Integrated Pest Management programs for tephritid pests. Sexually selected traits are frequently good indicators of male fitness and knowledge of sexual selection processes may contribute to the improvement of the sterile insect technique (SIT), to select genotypes with high reproductive success and to promote sexually selected phenotypes through mass-rearing optimization. Furthermore, males’ exposure to parapheromones, such as phenyl propanoids (PPs), ginger root oil and trimedlure can enhance the mating success of sterile flies used in SIT programs. PPs are also a powerful tool to improve reduced-risk monitoring dispensers and the male annihilation technique, with low side effects on non-target insects. Lastly, we outline the possibility to sensitise or train mass-reared parasitoids on OMPs during the pre-release phase, in order to improve their post-release performance in the field.

Description: Insect herbivores can become extensive invaders if they are able to undergo host expansions onto widely-grown agricultural host plants. An important yet unresolved question is whether all herbivore populations are equally able to utilize new host plants or if populations may be geographically structured, that is only a subset has the potential to undergo a host range expansion and become widely invasive. We examined if derived and ancestral geographic populations of L. decemlineata or Colorado potato beetle, varied in host preference and performance on both wild ( Solanum rostratum ) and cultivated ( Solanum tuberosum ) host plants. Sampling from six different North American regions (3 ancestral and 2 derived), we performed two full-factorial experiments to test for differences in host preference, acceptance, and performance on S. rostraum and S. tuberosum . Our results reveal the development of new (cultivated) host associations within pest populations of L. decemlineata following its geographic expansion. Pest beetles (i.e., Vermont populations) discriminated less between host plants and grew faster than all other beetle population on both host species. The Vermont beetles also developed faster on leaves than all other populations. The greater general preference, acceptance, and performance of Vermont beetles on all host types underscores the virulence of the pest form of the beetle and may help to explain the absence of pest incidence within the ancestral regions of L. decemlineata .

Description: Spinosad has been used to control Tuta absoluta in Brazil for more than a decade but will eventually be replaced by spinetoram despite the risk of cross-resistance. Therefore, the susceptibility to both molecules and the activity of detoxification enzymes were determined for eight representative populations of T. absoluta to assess resistance and the risk of cross-resistance. The LC 50 values for spinosad varied from 0.007 (Pelotas) to 0.626 mg/L (Sumaré); the LC 50 values for spinetoram varied from 0.047 (Pelotas) to 0.308 mg/L (Sumaré). The LC 99 values for spinosad varied from 0.23 (Pelotas) to 11.56 mg/L (Venda Nova do Imigrante); the LC 99 values for spinetoram varied from 0.55 (Pelotas) to 6.71 mg/L (Iraquara). The resistance levels ranged from 1.0- to 93.8-fold (RR 50 ) and 1.0- to 51.5-fold (RR 99 ) for spinosad and from 1.0- to 6.5-fold (RR 50 ) and 1.0- to 12.1-fold (RR 99 ) for spinetoram. The concentration-mortality responses to spinetoram were more homogeneous than those to spinosad. A strong correlation between the susceptibilities of T. absoluta populations to spinosad and spinetoram was observed, showing the similarity of the mode of action of both molecules and producing cross-resistance between them. The β–esterase activity of T. absoluta populations was correlated with spinosyn susceptibility, suggesting a potential contribution of the enzyme to evolved spinosyn resistance. The evolution of resistance to spinosyns in T. absoluta observed in this study suggests that strategies to mitigate resistance must be carefully implemented over the short term and that rotation with other products is encouraged.

Description: The rejection of citrus fruit caused by infestations of the California red scale (CRS), Aonidiella aurantii (Maskell) (Hemiptera: Diaspididae), raises concerns about its management. This fact has led to the introduction of new integrated control methods in citrus orchards, including the implementation of techniques based on pheromones. Previous works described efficient mating disruption pheromone dispensers to control A. aurantii in the Mediterranean region. The main aims of the present study were to adjust the timing of dispenser applications and study the importance of controlling the early first generation of A. aurantii by testing two different application dates: before and after the first CRS male flight. The efficacy of the different mating disruption strategies was tested during 2010 in an experimental orchard and these results were confirmed during 2011 in a commercial citrus farm. Results showed that every mating disruption strategy achieved significantly lower male captures in monitoring pheromone traps compared with untreated plots, as well as mean fruit infestation reductions of about 80 %. The control of the first CRS generation is not essential for achieving a good efficacy as demonstrated in two locations with different pest pressure. The late application of MD dispensers before the second CRS male flight has proven to be effective, suggesting a new advantageous way to apply mating disruption.

Description: The global spread of the Asian tiger mosquito Aedes albopictus , an urban pest as well as a vector for arboviruses, is a threat for public health. As control measures include the use of insecticides such as the pyrethroid λ-cyhalothrin, it is crucial to assess their efficiency and their potential impact on the biodiversity especially under climate change conditions. To evaluate the environmental risk, biotests are well established for non-target organisms but not yet for mosquitoes. We therefore developed a full-lifecycle biotest for mosquitoes kept under quarantine conditions based on the OECD guideline 219. Therewith we tested the effect of temperature and nutrition on the ecotoxicological response to λ-cyhalothrin on the mosquitoes Ae. albopictus and Culex pipiens by assessing sublethal and life history parameters. The efficiency of λ-cyhalothrin decreased in both mosquito species with increasing temperature and changed with feeding protocol. At effective concentrations for potential mosquito control in surface waters, λ-cyhalothrin poses a high risk for indigenous aquatic key role species inhabiting the same microhabitats. Those aspects should to be taken into account in vector control strategies.

Description: The Asian chestnut gall wasp Dryocosmus kuriphilus (DK) is one of the most important pests of chestnut trees worldwide, and sustainable control measures are urgently required for its control. In this study, the recurring mycoflora associated with DK galls in some Italian chestnut orchards was identified, and two Fusarium proliferatum strains (I3 and I4) were tested for their entomopathogenicity toward DK and their pathogenicity to chestnut in order to evaluate their potential as biocontrol agents. The two F. proliferatum strains, both isolated from the inside of DK galls and often covering dead bodies of larvae, pupae, and adults, caused a natural insect infection of about 4 % and resulted to be non-pathogenic to chestnut plants, while they induced 33 and 97 % of larvae mortality when applied in laboratory experiments to intact DK fresh or sectioned galls, respectively. Both strains infected maize seedlings, used as non-target hosts, and produced fumonisins in vitro. The efficacy in controlling DK in the galls, the absence of pathogenicity to chestnut, and the lower mycotoxin production indicated strain I3 as a promising biocontrol agent of the considered pest.

Description: Several sampling plans have been developed for many insect pest species. However, few sampling plans have been based on attractant-baited traps. The coffee berry borer Hypothenemus hampei (Coleoptera: Curculionidae: Scolytinae) is a key coffee pest of worldwide importance whose sampling plans usually demand the harvest and inspection of up to 5,000 coffee berries per field, which is labor-intensive, costly, and ineffective. Therefore, this system constitutes a good model for the development of a more cost-effective sampling plan based on attractant-baited traps for capturing adult insects allowing the sustainable management of this pest species. The reported study was performed in 27 coffee fields using berry damage-assessment techniques and capture of adult borers applying attractant-baited traps made of PET-bottles (polyethylene terephthalate bottles). The relationship between trap capture and berry damage was significant allowing the use of the former to estimate coffee loss caused by the borer. The trap capture data from the coffee fields were adjusted to a negative binomial distribution suitable for establishing a single conventional sampling plan for all investigated fields. The required trap density varied from 14 to 355 traps/10 ha, depending on the precision error selected. The sampling plan developed using spatial interpolation (kriging and inverse weighted-distance methods) indicated that using 22 traps/10 ha for sampling of the coffee berry borer, costing US$ 303.24/10 ha and requiring 49.14 min/10 ha for the sampling procedure, was suitable and resulted in cheaper, faster, and more reliable estimates compared to present recommendations.

Description: Olfactory orientation by aphids is guided by specific volatile blends released from their hosts. Host plants that co-exist with other plants may be less attractive for aphids due to volatile interactions between neighboring plants which can lead to changes in their volatile emissions. These changes in host plant volatile profiles induced by interactions between undamaged plants could be used to manage aphid populations in crops. When potato plants are exposed to volatiles from onion plants, the volatile profile of potato changes in relation to that of unexposed plants with consistently greater quantities of two terpenoids released. We examined the host plant searching behavior of aphids and showed that induced changes in plant volatile emissions affect aphid behavior. We assessed olfactory responses of winged and wingless aphids, Myzus persicae Sulzer (Hemiptera: Aphididae) to the changed volatile emissions. Both morphs were significantly less attracted to odors of potato plants that had been exposed to volatiles from onion than to odors of unexposed potato plants. Further, both morphs were significantly less attracted to synthetic blends mimicking volatiles emitted by onion-exposed potato plants than to blends mimicking non-exposed controls, and to single compounds emitted in greater quantities by exposed potato. Aphid morphs were repelled differently depending on the concentration of odor sources; winged aphids responded to higher doses than did wingless aphids. The aphid responses to changes in plant volatile profiles induced by neighboring plants may facilitate refinement of habitat manipulation strategies (e.g., intercropping) for integrated pest management to reduce aphid occurrence in crops.

Description: The white grub Holotrichia oblita Faldermann (Coleoptera: Scarabaeidae) causes serious damage in peanut fields in China. The development of an environmentally friendly control method for this pest is urgently needed. The efficacy of entomopathogenic nematodes against this pest in the laboratory and peanut fields was evaluated in this study. Both Steinernema longicaudum Shen and Wang and Heterorhabditis bacteriophora Poinar (Rhabditida: Steinernematidae and Heterorhabditidae) had promising control efficacy against H. oblita larvae in the laboratory. S. longicaudum X-7 and H. bacteriophora H06 at 1.0 × 10 4 and 5.0 × 10 3 IJs per plant caused a similar percentage reduction of the grub larvae and percentage of the injured legumes to chlorpyrifos. The peanut yields from the nematode-treated plots at 5.0 × 10 3 IJs per plant were at least 55 and 15 % higher than those from the water control and the chlorpyrifos-treated plots. No significant differences were found in the percentage reductions of the grub larvae at different larval stage applications. The peanut yields in plots treated by S. longicaudum X-7 and H. bacteriophora H06 were also not significantly different. The cost-benefit analysis showed that S. longicaudum X-7 and H. bacteriophora H06 are promising agents for H. oblita larvae control in peanut fields. Our findings indicate that entomopathogenic nematodes have good potential for safe management of H. oblita in peanut production.

Description: Efficacy of commercial formulations of Bacillus thuringiensis ssp. kurstaki ( Btk ) against spruce budworm Choristoneura fumiferana in black spruce ( Picea mariana (Mill.) BSP), white spruce ( P. glauca (Moench) Voss) and balsam fir ( Abies balsamea (L.) Mill.) was investigated in Québec’s Côte-Nord region. As expected, larval mortality was higher in Btk -treated plots (80.26 ± 2.34 %) than in control plots (66.32 ± 2.80 %). There were no differences in larval mortality among the three host tree species tested. Btk was most efficient in reducing spruce budworm defoliation when applied to black spruce and white spruce trees. Black spruce and white spruce exhibited lower final defoliation in Btk -treated plots than balsam fir. Btk applications produced a reduction in defoliation of 36 % in balsam fir, 44 % in white spruce and 41 % in black spruce. Control plots exhibited about 35 % higher amount of current-year foliage destroyed (AFD) and 56 % lower amount of current-year foliage remaining (ARF) than Btk -treated plots, whereas no differences in the amount of current-year foliage produced (AFP) were observed among host tree species. Black spruce trees showed the lowest AFD. Although not statistically significant, black spruce also showed the highest ARF. Our results suggest that Btk application is more efficient in protecting against spruce budworm damage when it is applied to spruce species than it is to balsam fir. It appears that the observed inter-specific differences in host tree foliage protection might be related to interactions between Btk , host tree foliage, and larval feeding behaviour.

Description: β -Damascone appeared a weak attractant close to not active to Myzus persicae , but modifications of its structure caused the avoidance of treated leaves by aphids during settling and reluctance to probe in simple choice- and no-choice experiments in previous studies. Here, the electrical penetration graph (EPG) technique, which allows monitoring of aphid probing within plant tissues, was applied to explore the biological background and localisation in plant tissues of the deterrent activities of β -damascone and its analogues. Activity of β -damascone and β -damascone-derived compounds depended on their substituents, which was manifested in the variation in the potency of the behavioural effect and differences in aphid probing phases that were affected. β -Damascone appeared a behaviourally inactive compound. The moderately active β -damascone ester affected aphid activities only during the phloem phase. The highly active deterrents—dihydro- β -damascol, β -damascone acetate, δ -bromo- γ -lactone, and unsaturated γ -lactone—affected pre-phloem and phloem aphid probing activities. The most effective structural modification that evoked the strongest negative response from M. persicae was the transformation of β -damascone into δ -bromo- γ -lactone. The behavioural effect of this transformation was demonstrated in frequent interruption of probing in peripheral tissues, which caused repeated failures in finding sieve elements, and reduction in the ingestion time during the phloem phase in favour of watery salivation. The inhibition of aphid probing at both the pre-phloem and phloem levels reveals the passage of the compounds studied through the plant surface and their distribution within plant tissues in a systemic way, which may reduce the risk of the transmission of non-persistent and persistent viruses.

Description: Recently, Apolygus lucorum (Hemiptera: Miridae) has become an important insect pest of Bt cotton and fruit trees in China. At present, the application of chemical insecticides is the main control option for this pest. We investigated the lethal effect of seven neonicotinoid insecticides on A. lucorum adults, including six commercialized neonicotinoids and a novel one, cycloxaprid, which is developed in China. In addition, we assessed the sublethal physiological (longevity, fecundity) and behavioral (pre-oviposition and oviposition periods) effects of LD 10 (low lethal dose) and LD 40 (moderate lethal dose) of cycloxaprid on the mirid bug. Lethal effect of the insecticides was determined using a topical exposure method; contact toxicity against the adults was ranked as follows: cycloxaprid, nitenpyram 〉 clothianidin 〉 acetamiprid, imidacloprid 〉 thiamethoxam 〉 dinotefuran. Among these insecticides, the toxicity of cycloxaprid against the adults was the highest; its LD 50 value was 2.54 ng a.i. (active ingredient)/adult. Both LD 10 (0.74 ng a.i./adult) and LD 40 (1.98 ng a.i./adult) of cycloxaprid induced sublethal effects in the adults; we observed a reduced longevity in males and the LD 40 also shortened the longevity of females. In addition, the LD 40 prolonged the pre-oviposition period and shortened the oviposition period of females, and it decreased their fecundity. The hatching rate of eggs laid by the females exposed to LD 10 and LD 40 greatly decreased (two-fold lower when exposed to LD 40 ). Our results demonstrate that cycloxaprid is among the best candidate insecticides for controlling A. lucorum , and it showed significant lethal and sublethal effects on this mirid bug.

Description: Studies were conducted in two apple orchards in 2009 and 2010 to examine whether the efficacy of mating disruption can be improved by co-applying microencapsulated (MEC) pear ester (DA-MEC) and codlemone (Ph-MEC) in comparison to DA-MEC and Ph-MEC treatments alone. Combined applications were made at a rate of 5 g a.i ha −1 DA-MEC + 25 g a.i ha −1 Ph-MEC in HV (635 L water ha −1 ) and ULV (40 L water ha −1 ) sprays. Moth catches were monitored weekly with delta-style traps containing 3 mg each of codlemone and pear ester. Moths in DA-combo traps were sexed and females were dissected to determine mating status. Codling moth catches did not differ significantly between the ULV and HV sprays of DA-MEC + Ph-MEC. The combinational MEC-treatments applied in both spray volume maintained good trap shutdown, each averaging 85 % reduction in moth capture over distant control orchards. While DA-MEC and Ph-MEC treatments alone disrupted male codling moth orientation to traps by 43 and 61 %, respectively. In the DA-MEC, Ph-MEC and combinational blocks, DA-combo traps caught a lower percentage (9–14 %) of female moths than those placed in both untreated and insecticide-treated blocks. In July and September, fruit damage was evaluated by visually inspecting a total of 1,200 randomly chosen fruits per orchard. Depending on the spray volume used, the combined MEC sprays reduced the number of fruits infested with larvae by 85–93 % compared with untreated control. In conclusion, DA-MEC can effectively augment pheromone mating disruption and offers additional control option for integrated pest management programmes.

Description: Many agricultural pests can be harboured by alternative host plants but these can also harbour the pests’ natural enemies. We evaluated the capacity of non-cotton plant species (both naturally growing and cultivated) to function as alternative hosts for the cotton leaf hopper Amrasca devastans (Homoptera: Ciccadellidae) and its natural enemies. Forty-eight species harboured A. devastans. Twenty-four species were true breeding hosts, bearing both nymphal and adult A. devastans , the rest were incidental hosts. The crop Ricinus communis and the vegetables Abelmoschus esculentus and Solanum melongena had the highest potential for harbouring A. devastans and carrying it over into the seedling cotton crop. Natural enemies found on true alternative host plants were spiders, predatory insects ( Chrysoperla carnea, Coccinellids, Orius spp. and Geocoris spp.) and two species of egg parasitoids ( Arescon enocki and Anagrus sp.). Predators were found on 23 species of alternative host plants, especially R. communis . Parasitoids emerged from one crop species ( R. communis ) and three vegetable species; with 39 % of A. devastans parasitised. We conclude that the presence of alternative host plants provides both advantages and disadvantages to the cotton agro-ecosystem because they are a source of both natural enemy and pest species. To reduce damage by A. devastans , we recommend that weeds that harbour the pest should be removed, that cotton cultivation with R. communis , A. esculentus, and S. melongena should be avoided, that pesticides should be applied sparingly to cultivate alternative host plants and that cotton crops should be sown earlier.

Description: There is lack of knowledge on the interactions between kernel aging and the simultaneous infestation by insects, both internal and external feeders. In the present paper, we report results obtained in arena-olfactometer assays in which we studied possible preference and behavioral relationships between the primary colonizer Sitophilus zeamais Motschulsky (Coleoptera: Curculionidae) and the secondary colonizer Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae). For this purpose, three experiments were conducted. The experiment I examined the response of S. zeamais adults at the fresh or stored kernels damaged by T. castaneum adults, compared to the control and the response of T. castaneum adults at the fresh or stored kernels damaged by S. zeamais adults, compared to the control. The experiment II examined the response of S. zeamais adults at the intact fresh or stored kernels conditioned at different conditioning intervals (1, 7, and 14 days) with kernels damaged by T. castaneum , compared to the control and the response of T. castaneum adults at the intact fresh or stored kernels conditioned at different conditioning intervals (1, 7 and 14 days) with kernels damaged by S. zeamais , compared to the control. The experiment III examined the response of S. zeamais adults at kernels contaminated at different contamination intervals by larvae or adults of T. castaneum , and the response of T. castaneum adults at kernels contaminated by larvae or adults of S. zeamais . In experiment I, significantly more S. zeamais adults were found in traps containing fresh or stored kernels damaged by T. castaneum than in the controls. Significantly more T. castaneum adults were found in traps containing fresh or stored kernels damaged by S. zeamais than in the controls. In experiment II, at 7 days of conditioning, significantly more adults of S. zeamais were captured in the traps used as control than in the traps containing either fresh conditioned kernels or stored conditioned kernels. At 1 and 14 days of conditioning, significantly more adults of T. castaneum were captured in the traps that contained stored conditioned kernels damaged by S. zeamais than in the controls. In experiment III, at 1, 7, and 14 days of contamination, significantly more adults of S. zeamais were captured in traps with kernels contaminated by larvae of T. castaneum or in the traps with kernels contaminated by adult females of T. castaneum than in the controls. Significantly more S. zeamais adults were found in traps containing kernels contaminated by T. castaneum adult males than in control kernels at the 7 and 14 days of contamination. At 1 day of contamination, significantly more adults of T. castaneum were captured in traps with kernels contaminated by larvae of S. zeamais than in the controls. The results of the present study suggest that kernels which were previously infested by S. zeamais were more prone to be selected by T. castaneum adults and kernels that were previously infested by T. castaneum were more prone to be selected by S. zeamais . Thus, the first colonizer can serve as the primary colonizer of stored grains, even if this first colonizer cannot infest sound kernels. The kernel age was also a crucial issue for the attraction of S. zeamais and T. castaneum . Stored kernels exhibited a stronger influence on the attraction of T. castaneum than for S. zeamais .

Description: The Khapra beetle, Trogoderma granarium Everts, is a global pest species of stored grain products. Accurate identification of Trogoderma specimens trapped within stores of grain is critical to surveillance and exclusion efforts for the Khapra beetle. To enhance diagnostic capacity, we report PCR-based diagnostic assays for Khapra beetle identification. Three methods such as conventional PCR, real-time PCR, and DNA sequencing are reported for the diagnosis of Trogoderma specimens captured within the U.S. All three methods discern the Khapra beetle based on variation in fragments of 16S mitochondrial DNA. To examine PCR assay stringency, ten native or introduced Trogoderma species and two Megatoma species were also examined. These DNA-based assays provide reliable identification of T. granarium regardless of condition, life stage, or taxonomic expertise of the investigator.

Description: Knowledge about host instar suitability of a parasitoid is critical to ensure bio-control efficacy. Studies were conducted to assess parasitizing and feeding behavior of a naturally occurring parasitoid, Eretmocerus hayati, on different instar nymphs of two invasive whiteflies, Bemisia tabaci (Gennadius) cryptic species MEAM1 and MED, in China. Er. hayati parasitized and fed on all nymphal stages of the two whiteflies, but preferred to parasitize 1st, 2nd and 3rd instar hosts of B. tabaci MEAM1 and 2nd instar hosts of B. tabaci MED. Parasitoids preferred to feed on earlier instar hosts of the two species. The preimaginal development times of parasitoids were the longest on 1st instar hosts, intermediate on 2nd and 3rd instars, and the shortest on 4th instars. The immature development time on B. tabaci MED hosts were slightly shorter than on MEAM1 ones. The highest parasitoid survivorships were on 4th instars, and the lowest were on 1st instars in both host species. The sex ratios of offspring remained stable at 0.5. Er. hayati could be a more suitable biological control agent for B. tabaci MED. Our results could provide guidance for indoor mass-rearing of Eretmocerus spp. for inundative release in the field, accelerating IPM programs against B. tabaci in China.

Description: The braconid parasitoid Psyttalia concolor foraging for larvae of Bactrocera oleae (Diptera: Tephritidae) uses olfactory cues from the larval microhabitat. However, it could rely on the sex pheromones of adults of its host, since B. oleae mating leks usually occur on olive plants and a high number of infested fruits can be easily located in their close proximity. We quantified the behavioural responses of P. concolor towards different doses of the two major sex pheromone components of B. oleae , the female-borne 1,7-dioxaspiro[5.5]undecane (DSU) and the male-borne ( Z )-9-tricosene (ZT). Results showed that P. concolor females and males were attracted only to the highest amounts of ZT (10 B. oleae male equivalents), regardless of the mating status. Wasps remained longer on the surfaces treated with high ZT amounts over the control. P. concolor females could exploit the ZT produced by lekking olive fruit fly males as a foraging kairomone. This could allow them to rapidly track B. oleae -infested olive plants, thus raising their chances to locate host larvae during their lifespan. On the other hand, the perception of ZT by P. concolor males could raise their chances to locate receptive females emerging from parasitised B. oleae pupae or also ovipositing in olive fruits. This study increases the knowledge of the reproductive biology of P. concolor, highlighting a case of chemical espionage in which a sex pheromone component from adult stages of the host is exploited both as a foraging kairomone by female parasitoids and as a sexual kairomone by male wasps.

Description: Oil seed rape ( Brassica napus L.) is one of the most commonly grown crops in Central Europe, and the brassica pod midge ( Dasineura brassicae Winn.) is one of the most important pests there. Insecticides against this pest applied during flowering may harm bees and other beneficial insects. The use of biostimulants such as nitrophenolates, which are not harmful to beneficial insects, can be an environmentally friendly way to control this pest. Nitrophenolates activate lignin synthesis in rape pods so the brassica pod midge is not able to penetrate pods. Nitrophenolates also regulate the efficiency of the photosynthetic apparatus, thus increasing yield. For these reasons nitrophenolates were tested in field conditions in Central Europe in 2005, 2007 and 2008. Nitrophenolates were applied on 10-m 2 plots, and their effect was compared to that of conventional insecticides. The number of damaged pods and yield parameters were assessed; the lignin content as well as photosynthetic rate was measured. Expression of genes related to lignin biosynthesis was examined in Arabidopsis thaliana L. The application of nitrophenolates decreased pod damage caused by the brassica pod midge. Expression levels of four genes related to lignin biosynthesis were increased after the application of nitrophenolates. The yield was higher in nitrophenolate-treated plots, which was attributed to an increase in the intensity of photosynthesis, higher chlorophyll content and improved chlorophyll a fluorescence parameters. The results showed that nitrophenolates have potential as a protective agent, but a further study is required. The application of nitrophenolates holds promise for reducing chemical input into the environment.

Description: The Chinese citrus fly, Bactrocera minax , is a major tephritid fruit fly pest that infests Citrus spp. fruits. The pest was removed from the national quarantine pest list in China in 2009 owing to its wide spread across the country, and it is currently considered a major threat to citrus industry in Asia. The frequent high infestation levels of B. minax in China emphasize the need for a more comprehensive understanding of its biology and ecology so that more efficient control measures can be developed and applied. In the framework of developing a sterile insect technique program against B. minax , we studied the feeding and mating activities of B. minax in situ ( Citrus orchards and surrounding habitats) through open field surveys and video recordings. In the pre-oviposition period, sexually immature adults largely foraged for food (e.g. honeydew from aphids, nectar and sooty mould) on non-host plants. Then, sexually mature adult flies shifted to lick sooty moulds, bird faeces and, to a lesser extent, an unknown substance on the Citrus leaves and fruits during the mating and oviposition periods. Finally, during the post-oviposition period, the flies were observed feeding on ooze from grapes. The mating behaviour patterns of B. minax in the field were described as follows: first, the male established its territory close to the potential oviposition substrate ( Citrus fruit), second, the female landed on the fruit and began inspection and ovipositor boring behaviour on the fruit surface (no male courtship observed e.g. wing vibration), and third, the male mounted and copulated with the female. The present study shed light on the feeding ecology and mating behaviour of B. minax in the field; this knowledge will facilitate development of better management strategies against this tephritid fly.

Description: Glyphosate-resistant (GR) hairy fleabane was first documented in California in 2007. A preliminary study comparing plants from this population to a glyphosate-susceptible (GS) population determined that they developed more rapidly than the GS plants. However, it was not known if this was a general characteristic of all GR populations. Therefore, seeds of hairy fleabane were collected from 122 locations in central California. Plants from each location were grown and tested for resistance using a shikimate enzyme assay. Seeds from 90 locations germinated of which 27 % were determined as GR, 21 % as GS, and 52 % as intermediate/mixed. Plants from five GR and five GS populations, as determined by the assay, were randomly selected for comparisons and were grown in 2010/2011. Time taken by each plant to reach key phenological stages was recorded and converted into growing degree day (GDD) using a base temperature of 4.2 °C. The biomass of each plant was recorded at seed set. The five GR and GS plants had similar phenological development rates and biomass. Therefore, the differences previously identified between the two populations were not present in the additionally tested populations. The phenological development was hence described by a common GDD model with the plants requiring 374, 711, 970, 1289, and 1551 GDD, to reach the rosette, bolting, first bud, first flower, and first seed stages, respectively. This study shows widespread distribution of GR hairy fleabane in central California, provides useful information on biology of this weed for management, and suggests possible label changes to herbicide manufacturers.

Description: The whitefly Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) is a worldwide pest which has become one of the main pests in tomato crops. The predators Macrolophus pygmaeus (Rambur) and Nesidiocoris tenuis Reuter (Hemiptera: Miridae) and the parasitoid Eretmocerus mundus (Mercet) (Hymenoptera: Aphelinidae) have shown their efficacy at controlling B. tabaci populations when used as biological control agents. Intraguild predation (IGP) between natural enemies can affect their effectiveness at controlling pests. In the present study, the interaction of these three natural enemies and their effect on B. tabaci was studied on tomato plants by combining morphological observations and molecular analysis of trophic interactions. Under the conditions used in the present study, no IGP was detected between M. pygmaeus and N. tenuis by either counting dead predators or by PCR using prey-specific cytochrome c oxidase I primers. However, predation on B. tabaci decreased when they coexisted on the same plant, which could compromise the biological control of this pest. Although PCR analyses using E. mundus -specific primers showed predation on B. tabaci -parasitized nymphs in 27 % of M. pygmaeus and 17 % of N. tenuis , B. tabaci control was improved when both predators coexisted on the same plant with the parasitoid. The combined use of E. mundus and M. pygmaeus / N. tenuis is therefore recommended in order to improve B. tabaci control in conservation biological control strategies.

Description: Wood-boring insect pests, such as the invasive Asian longhorned beetle (ALB, Anoplophora glabripennis ), are difficult to detect because larvae mine inside deciduous trees, logs or wood packing material. Currently, only visual survey methods are used, which are mostly unable to detect the presence of wood-boring insects. Bioacoustic detection, however, exploits sounds and vibrations produced by larvae during feeding and other movements inside the wood. Bioacoustic detection methods require mounting of the sensors, which can be complicated, time consuming and may even damage the surface of the tested material. Laser vibrometry avoids all these problems as vibrations produced by the larvae are detected via the laser beam. We used a portable digital laser vibrometer to detect the activity of mining ALB larvae within poplar logs. Three types of pulses were recorded: the broadband pulses lasting 1–2 ms were the most frequent, with frequency maxima between 8 and 13 kHz. Less frequent were the low and the high frequency pulses, covering frequency bands between 4 and 7, and 9 and 20 kHz, respectively. The signal-to-noise ratio across the whole frequency range (0–22 kHz) of the laser vibrometer was around 35 dB. We show that laser vibrometry can be successfully employed as a non-destructive diagnostic tool for detecting infestations by the wood-boring beetles.

Description: Using multiple pest-mortality sources is a basic tenet of IPM, but they may not always be compatible. To that end, we examined compatibility of parasitism and nucleopolyhedrovirus (NPV) infected. Specifically, we examined the effects of prior oviposition experience by Microplitis pallidipes on its ability to distinguish NPV-infected from healthy larvae of Spodoptera litura . We found that time spent searching for hosts was significantly lower, while the number of attacks, percentage of first attacks, and parasitism rate were all significantly higher in healthy versus virus-infected hosts for parasitoids that had experienced healthy hosts. Meanwhile, parasitoids that had experienced infected hosts spent significantly more time searching for infected hosts starting on day 2. For these parasitoids, the number of attacks, percentage of first attacks, and parasitism rate were all significantly lower from day 2 in virus-infected versus healthy larvae. We found no significant differences between parasitoids without experience versus ones experienced with infected hosts in search time for infected hosts, number of infected host attacks, or percentage of first attacks on infected hosts. In comparison, parasitoids that had experienced healthy hosts spent less time searching for healthy hosts than parasitoids without experience, and displayed a higher frequency of attack on healthy hosts and a higher percentage of first attacks on healthy hosts. Experience with healthy larvae aided parasitoids in distinguishing healthy from virus-infected larvae, but experience with virus-infected larvae did not convey the same discrimination. This information provides a better understanding of how to integrate NPV applications with naturally occurring parasitism for this pest in crops.

Description: Slugs are a serious pest of cereal crops, and recent emphasis in slug pest management has shifted from solely chemical towards integrated approaches. The objective of the present research was to test if boosted silicon (Si) and calcium (Ca) levels in wheat seedlings can reduce slug grazing. Laboratory experiments were conducted in which wheat seedlings were grown firstly, with soluble Si and Ca (with and without additional mineral N) or secondly, with six levels of soluble Si, and consumption of leave sections by the field slug ( Deroceras reticulatum ) was measured. Boosted foliar Si concentrations reduced consumption significantly ( P  〈 0.001) compared to an untreated control and Ca treatments in a no-choice setting; a similar trend ( P  〈 0.10), but with a higher variability, was observed in a simultaneous choice setting. It is shown for the first time that increasing the nominal Si concentration of treatment solutions in a geometric series (from 0 to 6 g sodium metasilicate nonahydrate l −1 ) translated into a logarithmic increase in foliar Si concentrations (from 5.0 to 19.4 g Si kg −1 dry weight). When these leaves were offered simultaneously (choice setting), wheat leaves containing less than 10 g Si kg −1 were consumed preferentially by D. reticulatum ( P  〈 0.001), suggesting that Si concentrations as low as 1 % leaf dry weight may be effective at reducing grazing by slugs. It is concluded that boosting Si levels in cereals has potential as a novel tool in crop protection against pest slugs and snails. Various open research questions to advance this tool are identified.

Description: Tuta absoluta (Meyrick) is an important pest of tomato. Mass trapping of males has seldom proved an effective control measure, probably due to the pest’s reproductive biology. There are few studies on female mating behaviour. For this reason, this study aimed to determine female mating frequency and its effects on reproductive output and female longevity; the effects of male mating status on female reproductive output and longevity and the fate of the spermatophore inside the bursa copulatrix. The studied population of T. absoluta mated only once a day at the beginning of the photophase, females remated frequently and can be classified as polyandrous. The refractory period of both T. absoluta males and females was very short and was not observed in many cases. The lack of refractory period could be due to the female’s rapid metabolism of the spermatophore thus allowing the female to reduce the intermating interval and mate again. Remating had direct benefits for T. absoluta females increasing their fecundity, fertility and longevity. These benefits were greater when females could remate to virgin males instead of to the same male. In this species, therefore, polyandry has direct benefits for the female. The occurrence of polyandry together with other known or unknown reasons can explain the failure of control methods based on pheromones in the open greenhouses in some tomato-growing areas.

Description: A number of species of the family Psyllidae, commonly called jumping plant lice, are economically important as vectors of pathogenic phytoplasmas in fruit crops. Pear psyllids of the species Cacopsylla pyri (L. 1758) (Psyllidae) are the most damaging pest of pear trees in Europe. These phloem feeding insects transmit pear decline, a disease caused by the phytopathogenic bacterium Candidatus Phytoplasma pyri. Knowledge of the signals used for intraspecific communication, especially during mating behavior, is essential to design ecological control strategies against this vector insect. Here, we report the first recordings of acoustic signals emitted by male and female C. pyri . We also observed the establishment of an acoustic duet between an interacting couple prior to mating. Furthermore, we found potentially sound producing stridulatory organs in male and female individuals of C. pyri . The acoustic signals recorded are described and presented. Possible stridulatory organs are depicted as scanning electron microscopy pictures. The implications of these findings for potential applications in pest control are discussed.

Description: Current understanding is that high planting density has the potential to suppress weeds and crop–weed interactions can be exploited by adjusting fertilizer rates. We hypothesized that (a) high planting density can be used to suppress Rottboellia cochinchinensis growth and (b) rice competitiveness against this weed can be enhanced by increasing nitrogen (N) rates. We tested these hypotheses by growing R. cochinchinensis alone and in competition with four rice planting densities (0, 100, 200, and 400 plants m −2 ) at four N rates (0, 50, 100, and 150 kg ha −1 ). At 56 days after sowing (DAS), R. cochinchinensis plant height decreased by 27–50 %, tiller number by 55–76 %, leaf number by 68–84 %, leaf area by 70–83 %, leaf biomass by 26–90 %, and inflorescence biomass by 60–84 %, with rice densities ranging from 100 to 400 plants m −2 . All these parameters increased with an increase in N rate. Without the addition of N, R. cochinchinensis plants were 174 % taller than rice; whereas, with added N, they were 233 % taller. Added N favored more weed biomass production relative to rice. R. cochinchinensis grew taller than rice (at all N rates) to avoid shade, which suggests that it is a “shade-avoiding” plant. R. cochinchinensis showed this ability to reduce the effect of rice interference through increased leaf weight ratio, specific stem length, and decreased root-shoot weight ratio. This weed is more responsive to N fertilizer than rice. Therefore, farmers should give special consideration to the application timing of N fertilizer when more N-responsive weeds are present in their field. Results suggest that the growth and seed production of R. cochinchinensis can be decreased considerably by increasing rice density to 400 plants m −2 . There is a need to integrate different weed control measures to achieve complete control of this noxious weed.

Description: Organophosphate (OP) insecticides have been an effective control of several tephritid pests. Recently, OP resistance has been observed in various fly species from different localities. However, in cases where resistance to an OP is exhibited in the field, evaluations of the efficiency of trapping with lures mixed with the same OP toxicants have not been carried out. To address this, the trapping and killing efficiency of lures with OP toxicants was assessed for flies from lines of Bactrocera dorsalis exhibiting resistance and susceptibility to OP insecticides. Specifically, bioassays were conducted with males from susceptible, resistant, and revertant lines (derived by relaxation of selection in the resistant line). The trapping and killing efficiencies of traps containing concentrations of 5 or 2.5 % naled were assayed at different exposure times. For the susceptible line, the number of dead flies found inside and outside of the trap was significantly lower than that of the other two tested lines. The number of dead flies found outside was significantly lower for the 2.5 % naled concentration compared to that of the 5 % concentration. Additionally, an analysis of genotypes showed that in trapped males, the frequencies of alleles of the acetylcholinesterase gene associated with resistance were lower compared to males of the field population collected from the same localities. In conclusion, for cases where fly lines exhibit insecticide resistance, the use of toxicant lures laced with the same insecticides may severely impact trapping effectiveness and may result in further increases of the frequency of resistant genotypes in the population.

Description: Contact toxicity of spinetoram was evaluated in laboratory bioassays on concrete, ceramic tile, galvanized steel, and plywood. The efficacy of spinetoram was assessed at dose rates of 0.025 mg (AI)/cm 2 , 0.05 mg (AI)/cm 2 , and 0.1 mg (AI)/cm 2 in two series of bioassays. The first series was conducted on concrete surfaces, with adults of Rhyzopertha dominica (F.), Sitophilus oryzae (L.), S. granarius (L.), Tribolium confusum Jacquelin du Val, Oryzaephilus surinamensis (L.), and Cryptolestes ferrugineus (Stephens). The second series was conducted at the same dose rates on all surfaces against adults of R. dominica , S. oryzae, and T. confusum . An equal number of dishes with and without food were used in both bioassay series. Mortality was assessed daily for 7 days for T. confusum and after this interval all live adults were removed and transferred to untreated surfaces with food and held under the same conditions. After the first week of daily evaluation, delayed mortality was evaluated 7 days later. For all the other species, mortality was measured after 5 days of exposure. The results of the first series of bioassays showed that T. confusum was the least susceptible to spinetoram-treated concrete surfaces. In contrast, all the other species were found susceptible, regardless of the dose and the presence of food. Regarding the comparison of different surfaces, our results illustrate that, with the exception of T. confusum , there were no significant differences among surfaces. The results of the present study indicate that spinetoram was effective against various species on several types of surfaces, and the presence of food did not influence its efficacy in most cases.

Description: Trap cropping is a useful tool in sustainable pest management. Trap crops usually target a single species or genus of insect pests. In this study, we assessed the potential of velvetleaf ( Abutilon theophrasti ) as a trap crop for two distant insect species, Bemisia tabaci and Sylepta derogata in Chinese cotton fields from 2006 to 2009. Under laboratory conditions, velvetleaf, a known trap plant of B. tabaci , was preferred over cotton by S. derogata for oviposition, and the subsequent offspring had greater survival and faster development on velvetleaf than cotton. Field-plot trials showed that population densities of S. derogata were 46–110 times greater on velvetleaf than on cotton, respectively. Commercial field trials indicated that S. derogata density and leaf damage were 79–90 % and 83–94 % lower in cotton fields inter-planted with sprayed velvetleaf strips than without them, respectively; whereas densities of B. tabaci were 21–51 % lower in fields with sprayed velvetleaf strips than in those without. At 〉10 m from velvetleaf strips, densities of B. tabaci and S. derogata in cotton gradually increased. Velvetleaf strips were an effective trap crop for simultaneous management of B. tabaci and S. derogata in cotton fields.

Description: In recent years, biological control strategies to control many major horticultural pests have been successfully implemented in the Eastern Mediterranean basin. However, the management of some pests, such as aphids in sweet pepper crops, can still be improved. The goal of this study was to examine the potential of the omnivorous predatory mirids Nesidiocoris tenuis , Macrolophus pygmaeus, and Dicyphus maroccanus as biocontrol agents of aphids in sweet pepper crops. First, the capacity to detect Myzus persicae -infested and un-infested plants was studied in a Y-tube olfactometer. Females of the three species of predatory mirids were strongly attracted to the odor of infested M. persicae plants. Second, the prey suitability of young and mature nymphs of M. persicae for these three mirid species was studied. The three species actively preyed on M. persicae , although D. maroccanus resulted the most voracious species preying both young and mature nymphs. Finally, the capacity of the three omnivorous predators to reduce M. persicae in heavily infested plants was determined in semi-field conditions. The three species of mirids could reproduce on aphids and establish on sweet pepper plants. Mirids significantly reduced the number of M. persicae per leaf, reaching levels of aphid reduction close to 100 % when compared to the untreated control. These results suggest that mirids might play a major role in aphid management in sweet peppers. The potential implementation methods of predatory mirids for the biological control in sweet peppers are discussed.

Description: Natural essential oils have received increased attention as alternatives to synthetic pesticides for pest management of foodstuffs. Recently, microencapsulation and other controlled release techniques are used to increase insecticidal efficiency and persistence of essential oils with slow and controlled release. In this study, the possibility of improving the insecticidal activity of plant essential oils was investigated for effective management of two stored product beetle pests. Self-assembly technique was used to prepare nanogels of myristic acid-chitosan loaded by essential oil extracted from cumin, Cuminum cyminum L. Fumigant toxicity of C. cyminum oil and oil-loaded nanogels (OLNs) were investigated at 4, 7, 10, 13, and 16 µL/L air against the granary weevil Sitophilus granarius L. and 8, 11, 14, 17, and 20 µL/L air for confused flour beetle Tribolium confusum Jacquelin du Val. Experiments were conducted at 27 ± 1 °C and 55 ± 5 % relative humidity in continuous darkness. Insecticidal bioassay revealed that OLNs were more toxic than C. cyminum oil against tested beetle pests. The persistence of the oil and OLNs was also evaluated against two tested species. Results indicated that C. cyminum oil completely lost its insecticidal activity after 12 days, whereas at the same period, the OLNs lost about 60 % of its activity when applied against S. granarius and 15% for T. confusum . Therefore, it could be concluded that encapsulation improved the persistence of the oil.

Description: The development of an integrated rodent pest management strategy requires the adoption of protocols that should be based on a good knowledge of species–habitat relationships. Vole damage to orchards has increased in Italy in recent decades, as new cultivation practices have been introduced, despite the use of rodenticides. To improve our understanding of factors influencing Savi’s pine vole abundance in Italian apple orchards, we monitored the relationship between environmental and agronomic variables and population densities. Vole population sizes were influenced by the abundance of voles in the neighbouring fields and the presence of kiwifruit orchards, usually not treated with rodenticides, bordering on apple orchards. The type of irrigation system had the strongest influence on vole abundance and flood-irrigated fields had fewer voles than drip-irrigated fields. Apple-tree age and tilling practices also had an influence on vole abundance. Our research provides evidence that vole populations are influenced mostly by agronomic practices and type and extension of fruit orchards. An integrated management strategy in the apple orchard district should include coordination in chemical treatments between farmers and the experimentation of flood irrigation and regular soil tillage management as a possible cost-effective way to reduce vole populations.

Description: The success of an invasive species can be reduced by biotic resistance from the native fauna. For example, an invader that is eaten by native predators is less likely to thrive than one that is invulnerable. The ability of invasive cane toads ( Rhinella marina ) to spread through Australia has been attributed to the toad’s potent defensive chemicals that can be fatal if ingested by native snakes, lizards, marsupials and crocodiles. However, several taxa of native insects and birds are resistant to cane toad toxins. If native rodents are also capable of eating toads (as suggested by anecdotal reports), these large, abundant and voracious predators might reduce toad numbers. Our field observations and laboratory trials confirm that native rodents ( Melomys burtoni , Rattus colletti and Rattus tunneyi ) readily kill and consume cane toads (especially small toads), and are not overtly affected by toad toxins. Captive rodents did not decrease their consumption of toads over successive trials, and ate toads even when alternative food types were available. In combination with anecdotal reports, our data suggest that rodents (both native and invasive) are predators of cane toads in Australia. Despite concerns about the decline of rodents following the invasion of toads, our data suggest that the species we studied are not threatened by toads as toxic prey, and no specific conservation actions are required to ensure their persistence.

Description: Currently, integrated pest management (IPM) of wireworms is not widespread in Europe. Therefore, to estimate the densities of three major wireworm species in southern Europe ( Agriotes brevis Candeze, A. sordidus Illiger, and A. ustulatus Schäller), bait traps were deployed pre-seeding in maize fields in north-eastern Italy between 1993 and 2011. Research discovered that there was a significant correlation between all three wireworm species caught in the bait traps and damage to maize plants, but damage symptoms varied. Wherever A. ustulatus was the main species caught, there was no significant damage to maize plants, but seeds were damaged. Most of the symptoms caused by A. brevis and A. sordidus were to the central leaf/leaves, which wilted because of feeding on the collar. A. brevis was the most harmful species; when more than one A. brevis wireworm was caught per trap, plant damage sometimes resulted in reduced yield. Five A. ustulatus larvae per trap caused the same damage to maize as one A. brevis . A. sordidus came second (threshold two larvae/trap). These thresholds are reliable for: (1) bare soil in which there are no alternative food sources; (2) average soil temperature 10 cm beneath the surface of above 8 °C for 10 days; (3) soil humidity near to field water capacity, but days of flooding have not been considered. The implementation of the practical method described herein may lead to effective IPM of wireworms in maize and to a significant reduction in the number of fields treated with soil insecticides.

Description: The Brown Treesnake ( Boiga irregularis ) is invasive in Guam and threatens to be dispersed by military and civilian transportation activities to other islands in the Pacific, where it could be expected to inflict similar damages. Prevention of inadvertent export of snakes in cargo and vehicles currently relies on trained canine detection teams, which are expensive to use and unable to detect all snakes. Hence, there has long been interest in developing effective and cheaper means of fumigating cargo to remove snakes. A companion study has shown that chemical fumigation is unlikely to be readily developed into a practical tool. Here, we demonstrate that these snakes are readily induced to quit test refugia by application of streams of heated air. Many parameters affect snake response times, but we find that application of relatively low temperatures (48–52 °C) at moderate delivery rates (3.4 m 3 /min) is sufficient to induce exit of these snakes within 5 min. Development of a portable heat-delivery system based on these findings has great potential to ensure snakes do not unintentionally stow away to other locations in cargo, munitions, vehicles, or airplane wheelwells. Application of such technology can be done on Guam as well as at locations receiving cargo or vehicles from that source, providing an additional layer of security in ensuring these snakes do not colonize additional locations outside their native range.

Description: Piezodorus guildinii (Westwood) is an important soybean pest in the Americas. Current knowledge about its ecology is limited. To implement holistic and sustainable pest management programs, it is necessary to understand how biotic and abiotic factors regulate its population. Seasonal occurrence on different host plants, and morphological (body morphometry and color) and physiological (lipid content and development of reproductive organs) changes in adults, were studied. Weekly samples were conducted during 2 years on Medicago sativa , Trifolium pratense , Lotus corniculatus (Leguminosae), Pittosporum undulatum (Pittosporaceae), Ligustrum lucidum (Oleaceae), Phyllostachys sp. (Poaceae), and in leaf litter of Eucalyptus sp. (Myrtaceae) at the survey sites (between 33°55′ and 34°17′S). On forage legumes, both nymphs and adults were intercepted, whereas on shrubs, bamboo, and in eucalyptus litter only adults were captured. Alfalfa was the forage legume on which adults were collected during almost the entire year. In this plant species, the abundance of adults and nymphs were higher in comparison with the other plants species and overwintering niches. From the beginning of autumn to the beginning of spring, adults were observed on the foliage of shrubs and bamboo. During autumn and winter, adults were observed underneath eucalyptus litter. In autumn and winter, adults had accumulated lipids reserves, showed undeveloped reproductive organs, smaller body size, and females showed clear coloration of the pronotum band and of the connexivum, indicating reproductive diapause. Results suggest that the control of P. guildinii during spring on alfalfa may reduce the population of bugs before they colonize soybean.

Description: In vitro and in vivo studies were developed to evaluate the compatibility of the six most common herbicides applied to the soil of olive orchards with the Metarhizium brunneum strain EAMa 01/58-Su for controlling Ceratitis capitata preimaginals. The fungus demonstrated high in vitro compatibility with the six active ingredients in malt agar medium, with growth rates ( a ) ranging between 2.5 mm d −1 (glyphosate + terbuthylazine) and 3.3 mm d −1 (oxyfluorfen). This compatibility was also revealed in vivo by assaying the fungus (1.0 × 10 8 conidia g soil −1 ) toward medfly prepupariating larvae in soil containing herbicides. Even if there was a decrease in the M. brunneum level in the soil up to 10 4 –10 5 conidia g soil −1 15 days after inoculation, mortality rates, which ranged between 70–80 %, did not differ significantly from the control, except the ones observed in soils that contained glyphosate and its herbicide combinations, in which a significant 50 % reduction of virulence was detected. These results reveal a general compatibility of M. brunneum with the most common herbicides applied to the soil of olive orchards, but a mixture of the fungus in the atomizer tank for simultaneous treatment beneath the tree canopy is recommended for all active ingredients except glyphosate.

Description: Control efficacy of sandalwood oil ( Santalum austrocaledonicum Vieill) and its main components, α- and β-santalol, which have not been tested before against Aphis gossypii Glover (Hemiptera:Aphididae), was investigated in the laboratory, greenhouse and field bioassays. The main constituents of the commercial sandalwood oil were found to be α-santalol (47.5 %), β-santalol (18.7 %), bergamotol (7.2 %) and lanceol (9.1 %) according to GC and GC-MS analyses. The sandalwood oil was fractionated into an α-santalol-rich fraction (RF), β-santalol RF, and a mixture of α- and β-santalols by silica gel column chromatography. The purity of α-santalol RF was 75.4 % (ratio of α-:β-santalol was 94:6) and that of β-santalol RF was 34.6 % (ratio of α-:β-santalol was 16:84). Laboratory bioassay showed that sandalwood oil, α- and β-santalol RFs had the same and significantly higher repellency and control efficacy against A . gossypii than the two control treatments and that a mixture of α- and β-santalols was toxic to the aphid. Santalol was comparable to imidacloprid (a neonicotinoid insecticide) in its efficacy against A . gossypii infesting Rose of Sharon, Hibiscus syriacus L., with 98.8 % mortality. The control efficacies of sandalwood oil (94.0 %), α-santalol RF (84.2 %), β-santalol RF (90.6 %) and a mixture of α- and β-santalols (88.7 %) against the A . gossypii infesting hot peppers were also comparable to each other in the greenhouse bioassay. Considering its control efficacy against A . gossypii , the application of sandalwood oil and its components may open the possibility of environmentally friendly management of A . gossypii .

Description: The brown marmorated stink bug, Halyomorpha halys , is an agricultural and household pest native of far East. In the last years, it has spread to and established in countries outside its area of origin, most notably in North America (United States and Canada), causing severe economic losses in agricultural crops. Recently, H. halys has been found in Europe (Switzerland, Germany, France, Hungary, and Greece) and since September 2012, it has also been found in Italy. However, the modalities of introduction and spreading of this pest on the Italian territory are unknown. Tracing back the diffusion modes of the species by analyzing the genetic structure and composition of populations in their initial phase of colonization could be useful also in the view to implement better pest control strategies. The present study aimed to identify the potential pathways of entry of H. halys by detecting the genetic diversity of specimens collected from Northern Italy and Canton Ticino (Southern Switzerland). The analyses of 1,175 base pairs of mtDNA cytochrome c oxidase I and II genes ( cox1 and cox2 ) on 42 specimens led to the identification of four combined haplotypes: one, found in Emilia Romagna region, is the same found in China and North America but never observed before in Europe. The other combined haplotypes are new but consistent in part with haplotypes previously found in Switzerland. Present data indicate that the Italian invasion may have occurred from two different pathways, both from Switzerland and from Asia and/or North America.

Description: Over the last few decades, important advances have been made in understanding of host–parasitoid relations and their applications to biological pest control. Not only has the number of agent species increased, but new manipulation techniques for natural enemies have also been empirically introduced, particularly in greenhouse crops. This makes biocontrol more complex, requiring a new mathematical modeling approach appropriate for the optimization of the release of agents. The present paper aimed at filling this gap by the development of a temperature- and stage-dependent dynamic mathematical model of the host–parasitoid system with an improved functional response. The model is appropriate not only for simulation analysis of the efficiency of biocontrol agents, but also for the application of optimal control methodology for the optimal timing of agent releases, and for the consideration of economic implications. Based on both laboratory and greenhouse trials, the model was validated and fitted to the data of Chelonus oculator (F.) (Hym.: Braconidae) as a biological control agent against the beet armyworm, Spodoptera exigua Hübner (Lep.: Noctuidae). We emphasize that this model can be easily adapted to other interacting species involved in biological or integrated pest control with either parasitoid or predator agents.

Description: Apple sawfly ( Hoplocampa testudinea Klug) is a serious pest in European organic apple production. They hatch during a short period only, making correct timing of control measures crucial. Swedish organic growers have requested a strategy for optimal timing of the Quassia amara (Simaroubaceae) extract against the apple sawfly. The aim of this study was, therefore, to develop methods to predict the timing of Q. amara control in Sweden. A temperature sum model for timely placement of monitoring or mass-trapping sticky traps was validated for Swedish conditions. The average emergence of sawflies occurred at 169 degree days (SD = 20) counted from March 15 (threshold temperature 4 °C). The difference in emergence from existing first flight model of average and maximum 9 and 39 degree days (1 and 9 calendar days) was found acceptable. Accumulated oviposition of 85 % at full bloom (BBCH 65) suggests that mass trapping and monitoring could stop at this time. This is supported by a tendency of decreased trap catches during that period. Three application times for Q. amara were compared: (A) at petal fall (BBCH 67), (B) at a date calculated using female trap catch numbers and temperature sums, and (C) prior to peak egg hatch observed in the field. All treatments resulted in significantly lower percentage of damaged apples compared to the unsprayed control, with significantly less damage (1.3 %) in plots treated according to method (B). The results provide information on adult phenology and methods that could be used to determine timing of mass trapping and insecticide application against the apple sawfly.

Description: The green peach aphid, Myzus persicae (Sulzer), is a generalist insect herbivore capable of using a wide range of cultivated plants and weeds. In this laboratory study, we examined the inter-clonal variation in M. persicae ’s ability to exploit the wild peach Prunus davidiana , a source of genetic resistance to aphids used by peach breeding programs. An initial screening of a set of sexually reproducing clones collected from commercial orchards planted with susceptible varieties found significant genetic variation in aphid survival on P. davidiana . Comparison of two clones (Fr2 and Fr12) found marked differences in colony sizes achieved. A detailed analysis of probing and feeding behavior showed that the clone exhibiting the highest performance on P. davidiana (Fr2) initiated probing earlier than the lower performing clone (Fr12). Periods of non-probing were also significantly shorter for this clone. Finally, Fr2 produced more and longer events of watery saliva injection into sieve elements. We discuss these results in terms of host plant adaptation by aphids and their capacity to overcome plant-resistance genes.

Description: Biological invasions are a leading threat to native wildlife, human health and food production worldwide. Understanding the invasion history helps identifying introduction pathways and organizing integrated management strategies especially aimed at avoiding multiple reintroductions. We coupled a recently developed spatial analysis (Geographic profiling) with trade flows quantification to identify the most likely spreading centre of a recent invader of Europe, the spotted wing drosophila, Drosophila suzukii . This polyphagous vinegar fly recently colonized western countries, where it is heavily threatening fruit production causing severe economic losses. Characterized by a rapid spread and a huge impact, the invasion of this pest has a few precedents and it is becoming a model in invasion biology and pest management. Thanks to our spatial approach based on data presence of D. suzukii in European countries in the very first years of it spread, we update the current knowledge of a first spread in Spain and Italy, suggesting on the contrary that the South of France may be the most likely spreading centre of D. suzukii in Europe. Estimates of propagule pressure (fresh host fruits importation) support this finding as imports from contaminated South East Asian countries are higher in France than in Spain or Italy. Our study provides a first step in the comprehension of invasion history of this pest species and emphasizes geographic profiling as an efficient technique to track down invaders colonization patterns.

Description: The diversity and abundance of natural enemies of insect pests is often higher in agroforestry plantations than in sun-exposed monocultures, and it is often assumed that this will lead to improved pest suppression. The effect that incorporating trees in cropping systems will have on pest populations, however, also depends on the habitat requirements of the pests themselves. In Eastern Uganda, we studied how shade level (full 〉50 trees per acre, moderate 21–50 trees per acre, and low 0–20 trees per acre) and altitude (high 1,717–1,840 m.a.s.l. and low 1,511–1,605 m.a.s.l.) influenced the abundance of the white stem borer Monochamus leuconotus and the coffee berry borer Hypothenemus hampei . We found that the effect of shade trees differed between the two pest species. The coffee berry borer was more common on sun-exposed plantations, whereas the white stem borer was more common in shaded plantations. Furthermore, the effect of shade level on the white stem borer depended on altitude, with the differences between shade levels being most pronounced in plantations at low altitudes. This implies that the impact of agroforestry on pest regulation both under current conditions and in a global warming scenario will be highly context dependent; it will depend on the identity of the most important pests in the area, and on environmental factors such as altitude.

Description: Two exotic European click beetle species, Agriotes obscurus and Agriotes lineatus, were introduced into the lower Fraser valley of British Columbia over a century ago, and are now predominant pests of a number of arable crops. A semiochemical-based method of monitoring both species has been developed as a part of an integrated pest management plan, and there is interest in mass trapping with pheromones as a management tool. A. obscurus females produce primarily geranyl octanoate (G8) and geranyl hexanoate (G6), while A. lineatus females produce both G8 and geranyl butanoate (G4). The current studies examined the possibility of using a blend of G8, G6, and G4 components in a single lure to trap both species simultaneously. A blended G8, G6 and G4 lure in a 1:1:1 ratio was, on average, 1.42 times more attractive to A. lineatus males than standard A. lineatus pheromone lures, but caught only 0.24 times the number of A. obscurus in standard A. obscurus traps. Blended traps, therefore, are effective for monitoring and mass trapping of A. lineatus , but only for detection of A. obscurus .

Description: This paper presents the first report of the occurrence of Drosophila suzukii (Diptera: Drosophilidae) in South America. Several samples were collected during various seasons in 2012 and 2013, and a significant number of individuals were obtained and identified. Based on the data recorded during each sampling campaign, including the locality, temperature, time of year, and number of individuals collected, several conclusions were drawn about the development of this invasion in southern Brazil.

Description: Live organisms intercepted from treated commodities during phytosanitary inspections usually arouse suspicions of treatment failure, sub-standard treatment application, or post-treatment infestation. The additional possibility that some treatments could kill slowly, meaning commodities might be inspected before pests have succumbed, is seldom considered for treatments other than irradiation. We used a novel biochemical viability assay to measure delays between methyl bromide fumigation and mortality of dipteran eggs, and evaluated the correspondence between egg viability and egg morphological features. Our experimental conditions simulated shipping of rock melons from Australia to New Zealand by sea and air. No eggs survived fumigation, but they took 3–20 days to die, whereas phytosanitary inspections of rock melons occur within 2–7 days. Delays were not influenced by methyl bromide concentration, but were significantly lengthened by cooler storage temperatures. Methyl bromide’s preservative effects delayed degradation of egg morphology, so the biochemical assay detected mortality long before morphological signs of egg death appeared. The results show that commodities subjected to effective methyl bromide treatments are at risk of being inspected before all pests have either died, or started to exhibit morphological signs of death. This could cause commodities to be unnecessarily rejected by quarantine authorities. Better methods than inspection for live pests are needed to assist authorities to gain assurance that treated commodities have been effectively disinfested. These could be developed by exploiting biochemical responses of pests and commodities to treatments.

Description: Flavescence dorée (FD) is one of the most economically important grapevine diseases in Southern Europe, and it is associated with phytoplasmas, phloem-limited wall-less bacteria. Recovery from disease naturally occurs in infected grapevines during the following seasons after infection. The capability of the leafhopper vector Scaphoideus titanus to acquire FD phytoplasma (FDP) from recovered and infected grapevines of Barbera and Nebbiolo varieties was investigated in North-western Italy vineyards monitored from 2007 to 2011. Pathogen concentration was quantified by real-time PCR in FDP-infected grapevines and broad beans, also used as source plants under controlled conditions, to correlate acquisition capabilities and phytoplasma titre in source plants. S. titanus acquired FDP from infected, but not from recovered, grapevines. FDP titre was higher in Barbera than in Nebbiolo and higher in summer than in spring, and acquisition efficiency and pathogen titre in source plants were positively correlated, both in field and laboratory conditions. Recovered plants do not represent a source of inoculum for the vector and therefore do not contribute to FDP spread. The inability of recovered plants to serve as FDP acquisition sources for the vector as well as the effect of the season and of the two grapevine varieties on the FDP acquisition efficiency are relevant results to re-design disease management practices, especially since insecticide treatments against the vector are not fully effective, and newly designed successful control strategies are required.

Description: B and Q putative species of Bemisia tabaci are two of the most invasive pests in the world. In China, Q is displacing B, but the underlying mechanism has been poorly explored. The difference in tolerance to host plants between B and Q may shed some light on the displacement. In the present study, two types of resistance (antixenosis or antibiosis) of cabbage and pepper against B and Q putative species were characterized based on demographic parameters (host selection, fecundity, etc.) and feeding behavior [as determined by electrical penetration graph (EPG)]. Female longevity, fecundity, and nymph survival were substantially higher on cabbage than on pepper for B, but were similar on the two hosts for Q. B nymphs suffered high mortality on pepper, suggesting a high level of antibiosis against B in pepper. Both B and Q preferred to settle and oviposit on cabbage rather than on pepper, indicating a high level of antixenosis against B and Q in pepper. With regard to feeding behavior, EPG data indicated that both B and Q whiteflies fed more efficiently on cabbage than on pepper. Overall, both B and Q preferred cabbage to pepper, and both performed better on cabbage than on pepper, but the negative effects of pepper were greater on B than on Q. Our results demonstrate that Q is more tolerant of a low suitability host than B, which may partially explain why Q has displaced B in China.

Description: In the present work, the insecticidal effect of two pirimiphos-methyl formulations [emulsifiable concentrate (EC) and capsule suspension (CS)] as surface treatment on concrete, plywood, galvanized metal, plastic, and ceramic tile was evaluated in laboratory bioassays against Sitophilus granarius (L.), Rhyzopertha dominica (F.), and Tribolium confusum Jacquelin du Val. Pirimiphos-methyl was applied at two-dose-rates, 0.01 and 0.1 mg/cm 2 , and insect mortality was assessed after 1, 2, 3, 4, 5, 6, and 7 days of exposure. After the final mortality count, alive individuals were transferred to untreated dishes, and delayed mortality was evaluated after an additional period of 7 days. In another series of laboratory bioassays, the residual efficacy of these two pirimiphos-methyl formulations on concrete was evaluated against S. granarius , R. dominica , and T. confusum. Pirimiphos-methyl was applied at two-dose-rates, 0.01 and 0.1 mg/cm 2 , on concrete dishes which were either kept in continuous darkness or exposed to light. A bioassay was initiated at the day of storage and every 4 weeks for 4 consecutive months (5 bioassays in total). Mortality of the exposed adult beetles was measured after 3 and 7 days of exposure. Both formulations were highly effective, with S. granarius being the most susceptible species. In general, mortality of the exposed beetles was not significantly affected by the surface type, with the exception of the significantly lower mortality counts of S. granarius adults on ceramic tile. CS appeared to be much more persistent on concrete than EC for all three species tested. Moreover, CS was not affected by light. In contrast, in some of the combinations tested, EC performance was poor in dishes that were exposed to light, in comparison with dishes that were in continuous darkness. We conclude that the surface type does not significantly and consistently affect S. granarius , R. dominica , and T. confusum mortality after surface application of the two pirimiphos-methyl formulations tested. Furthermore, CS can provide long-term protection when applied on concrete surfaces.

Description: The physicochemical characterization and residual insecticidal activity of poly(ethylene glycol) (PEG) nanoparticles containing essential oils (EOs) from geranium ( Geranium sp.) and bergamot ( Citrus reticulata L.) were evaluated against Blatella germanica for 1 year. The nanoparticles’ size increased during the storage time from 〈235 to 〈450 nm; the EO content decreased approximately 50 %, and the abundance of the major components did not show any differences between pre- and post-formulation. The surface characteristics of nanoparticles were analyzed by transmission electronic microscopy. The EO nanoparticles produced a notable increase in the residual contact toxicity apparently because of the slow and persistent release of the active terpenes. In addition, the nanoformulation enhanced the EO contact toxicity. The results indicate that these novel systems could be developed as control agents against German cockroaches.

Description: The silverleaf whitefly, Bemisia tabaci (Gennadius) biotype B (Hemiptera: Aleyrodidae), is considered one of the most important pests of cowpea ( Vigna unguiculata L. Walp.), limiting the productivity of this crop worldwide. Chemical control is still the main strategy for the management of populations of this insect. However, due to the harmful effects of pesticides on the environment and to humans, less injurious alternatives have been investigated. Along this line, the use of resistant genotypes can be a valuable tool for the control of the silverleaf whitefly. In this paper, we investigate some biological aspects of B. tabaci biotype B confined on 14 genotypes of cowpea. We evaluated the incubation period, egg viability, duration of nymphal stages, total duration of the juvenile phase, instar mortality and total mortality of the immature stage. The genotype MNC 99-541 F21 exhibited antibiosis against the whitefly, prolonging the lifecycle of the insect. The genotypes Canapu, BRS-Urubuquara and TE97-304 G-4 also exhibited antibiosis, causing high nymphal mortality. These results may help in breeding programmes to develop cowpea lines with resistance to B. tabaci biotype B.

Description: Tribolium castaneum is a pest of stored foods that causes serious economic losses. Understanding insect nutritional requirements and the effects of different diets on insect development can provide tools for developing strategies to control insect and integrated pest management systems. In this work we studied the performance of the T. castaneum on different plant diets composed of Vigna unguiculata , Phaseolus vulgaris and wheat flours. The diets interfered differentially with development and insect survival. Larvae size was reduced about 60 % in larvae fed with V. unguiculata flour. A delay in pupae formation was also observed. The larval mortality of 100 % was observed in the P. vulgaris diet. Carbohydrate and triglyceride showed variations during development and with different diets. Larvae fed with wheat diets showed a high concentration of carbohydrates 21 days after hatching (DAH) and triglyceride at 15 and 21 DAH. Larvae fed with wheat diets showed α-amylase activity during development. At 15 DAH the activity of larvae fed with V. unguiculata increased about 50 %. Cysteine protease activity in larvae fed with wheat remained high throughout development. Serine protease activity also varied according to diets. These results show that the nutritional state of developing larvae varies greatly with respect to triglycerides, carbohydrate and digestive enzymes depending on the diet and larval stage. Altogether, these results show that changes in dietary nutrients can interfere with insect physiology. Therefore changes in diet composition that may deprive insects of essential nutrients or include toxic compounds might be a good control strategy for stored product pests.

Description: During the last few years following the invasion of European tomato crops by the invasive South American tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), several indigenous larval parasitoid species were recorded as natural enemies of this pest. Necremnus cf. artynes (Walker) and to a lesser extent Stenomesius sp. nr. japonicus (Ashmead) (Hymenoptera: Eulophidae) have been frequently reported attacking T. absoluta in tomato greenhouses in Europe and they are considered as possible biocontrol agents. Few biological data are available on these two species, notably when they parasitize T. absoluta . Therefore, the present study documents their biology when parasitizing T. absoluta , and provides scientific bases for potential development of biological control programs relying on larval ectoparasitoids in invaded areas. We demonstrated the ability of the two parasitoid species to reproduce on T. absoluta as host on tomato plants. On average, N. cf. artynes female parasitized 28.5 larvae and killed 26.2 larvae during its life time whereas S. sp. nr. japonicus female was more long-lived and consequently more efficient; it parasitized 144.3 larvae and killed 90.1 larvae. In a second step, we also explored the effect of T. absoluta larvae instar on parasitism by S. sp. nr. japonicus and subsequent development of the parasitoid offspring. Best results were obtained with the third larvae instar with a higher number of offspring produced, bigger individuals and a higher proportion of females. Our results support the hypothesis that the two species are good candidates for biological control programs targeting T. absoluta in Europe.

Description: The use of systemic insecticides as seed treatments has raised concern about the possible impacts of these products on natural enemies. This study assessed the effects of sunflower seed treatments with chlorantraniliprole and thiamethoxam on Chrysoperla carnea by exposing larvae and adults to sunflower stem segments grown from treated seeds and the nectar secreted by their extrafloral nectaries. Confinement of larvae with stem segments for their entire developmental period had no effect on their survival or any life history parameter, except that the sex ratio of resulting adults was lower in the thiamethoxam treatment than in chlorantraniliprole. However, when adult pairs of C. carnea were exposed to treated stem segments during their maturation period, their subsequent survival and fecundity was significantly reduced by both materials, with thiamethoxam reducing median survival (LT 50 ) and fecundity to a greater degree than chlorantraniliprole. Insufficient offspring were obtained from adults exposed to thiamethoxam to permit assessment of their fitness, but the offspring in the chlorantraniliprole-exposed adults had reduced larval survival relative to controls. The greater impact of seed treatments on adult lacewings may be partly attributable to their greater consumption of extra-floral nectar. Our results indicate that seed treatment with systemic insecticides can cause negative effects on beneficial insects, potentially disrupting their population dynamics, and should not be assumed compatible with biological control and IPM simply because this mode of application limits direct exposure.

Description: Though rarely used in this way, biological control could potentially be exploited for managing spread of invasive species. Because spread of invasive species emerges from the combined action of population growth and dispersal, natural enemies that affect either of these processes should also affect spread. Dispersal of parasitoid species plays a key role in determining their impact on population growth of an invading host species along their expanding population front. In contrast, dispersal of most true parasites only occurs via movement of hosts so any impact that parasites may have on host dispersal may limit the parasite’s own capacity to keep up with an expanding host population. We test this premise by examining field data from what is probably the best example of the successful use of true parasites in biological control: the nematode Beddingia (= Deladenus ) siricidicola, which is released for management of Sirex noctilio populations. We analyze the historical impact of nematode releases on the rate of spread of invasive S. noctilio populations in Southern Argentina. Our findings suggest that, nematode releases did not discernibly slow the spread of S. noctilio populations. We conclude that although entomophagous parasites could be effective at reducing the growth and dispersal of localized host populations, they are unlikely, unless widely released through the leading edges, to slow the spread of invading hosts.