ALBERT

Notes: A polymerase chain reaction (PCR)-based assay to detect nervous necrosis virus (NNV) in fish was developed by using two sets of primers designed on a highly conserved region of the coat protein gene encoded by RNA2 of NNV. The first pair of primers amplified a fragment of 605 bp by one-step reverse-transcription (RT)-PCR, while the second pair amplified an internal segment of 255 bp by nested PCR. Addition of nested PCR increased the assay sensitivity 100-fold when carried out in a separate tube (two-step assay) and 10-fold when performed in the same tube (one-step assay). The sensitivity of the two-step assay was 104 times higher than that of virus cultivation. Nested PCR served also to confirm the specificity of the first amplification, as verified also by Southern hybridization analysis and direct sequencing. In species known to be susceptible to infection, such as European sea bass, Dicentrarchus labrax, and gilthead seabream, Sparus aurata, NNV was often detectable in brain tissue by RT-PCR alone but only by the two-step assay in blood, sperm, ovarian tissue or larvae. The same was true for sperm and ovarian tissue of shi drum, Umbrina cirrosa. NNV was also detected in the brains of Japanese red seabream, Pagrus major and brown meagre, Sciaena umbra, suggesting that these species can also be infected. No NNV was detected in samples of Artemia salina nauplii and rotifers obtained from a fish farm with an NNV outbreak. The inclusion of nested PCR in the assay appears to be necessary to screen out NNV-positive broodfish by blood sampling and testing of their larval progeny.

Notes: The relationship between contamination of potato seed tubers with Erwinia carotovora ssp. atroseptica (Eca), blackleg disease development, and the incidence and level of progeny tuber contamination in field grown crops was studied in 1998, 1999 and 2000. Seed tubers were inoculated by vacuum infiltration at three levels (low, intermediate and high) with a streptomycin-resistant marker strain of Eca (SCRI1039Str) and planted in the field. Blackleg disease development was directly related to the level of seed tuber contamination. The higher the level of seed tuber contamination, the earlier in the season blackleg disease appeared and the greater the final level of disease, which continued to rise as the season progressed. High and low levels of seed tuber contamination were related to high and low incidences of progeny tuber contamination, respectively, at all sampling times. However, an intermediate degree of seed tuber contamination tended to be associated with a low level of blackleg disease, a variable incidence of progeny tuber contamination early in the season but a high incidence later in the season. The level of progeny tuber contamination, derived from seed tubers inoculated at the three different levels of Eca, was categorized into four contamination classes (〈 102, 102–103, 103–104 and 〉 104 marker strain colony-forming units/mL peel extract). At the lowest level of seed tuber contamination, progeny tuber contamination tended to be in the two lower categories. However, as seed tuber contamination increased, the proportion of contaminated progeny tubers in the two higher categories also increased. Overall, the results suggest that progeny tuber contamination is related to seed tuber contamination and blackleg disease, and that the threshold level of seed tuber contamination remains an important factor in predicting both blackleg disease and tuber health.

Notes: Community expectations and research demonstrate that consumers play an important role in shaping services for women with breast cancer. Consumer contribution has been mandated recently in Victoria, Australia, to ensure the inclusion of consumer involvement in the planning and decision-making processes within health organizations. As part of the redevelopment of breast services in Victoria, Southern Health has been funded to plan local improvements to care co-ordination for women diagnosed with breast cancer in the southern metropolitan area of Melbourne. The establishment of effective consumer participation in breast services is an integral aspect of this project and a range of initiatives has been undertaken to achieve meaningful consumer involvement including the appointment of a consumer advisor; appointment of staff with extensive knowledge in women's health and community development to the project; establishment of a consumer reference group; and plans made to improve the receptivity of health service systems to consumer input. A preliminary evaluation of this ongoing project has indicated that a productive role for consumers in service practice review and policy and planning activities has been established and some change and engagement of staff has occurred. There is still work to be done to promote the involvement of a wider range of health professionals and to increase the level of trust between consumers and staff.

Notes: 1. The Lotic Intersite Nitrogen eXperiment (LINX) was a coordinated study of the relationships between North American biomes and factors governing ammonium uptake in streams. Our objective was to relate inter-biome variability of ammonium uptake to physical, chemical and biological processes.2. Data were collected from 11 streams ranging from arctic to tropical and from desert to rainforest. Measurements at each site included physical, hydraulic and chemical characteristics, biological parameters, whole-stream metabolism and ammonium uptake. Ammonium uptake was measured by injection of 15N-ammonium and downstream measurements of 15N-ammonium concentration.3. We found no general, statistically significant relationships that explained the variability in ammonium uptake among sites. However, this approach does not account for the multiple mechanisms of ammonium uptake in streams. When we estimated biological demand for inorganic nitrogen based on our measurements of in-stream metabolism, we found good correspondence between calculated nitrogen demand and measured assimilative nitrogen uptake.4. Nitrogen uptake varied little among sites, reflecting metabolic compensation in streams in a variety of distinctly different biomes (autotrophic production is high where allochthonous inputs are relatively low and vice versa).5. Both autotrophic and heterotrophic metabolism require nitrogen and these biotic processes dominate inorganic nitrogen retention in streams. Factors that affect the relative balance of autotrophic and heterotrophic metabolism indirectly control inorganic nitrogen uptake.

Notes: 1. We predicted that zebra mussel, Dreissena polymorpha (Pallas), genetic structure in the Mississippi River would follow a model of invasive species genetics, which predicts low genetic structure among populations of recently established species. This prediction was upheld in our previous genetic study using allozymes, however, one locus yielded anomalous results.2. We employed amplified fragment length polymorphism (AFLP) analysis as a neutral marker to assess the amount of genetic structure within and among populations, and as a test of expected population structure from both invasion genetic theory, and the results from our previous study.3. There was greater spatial differentiation, as measured by Fst, observed using AFLP's than for allozymes (P 〈 0.001). There was no evidence that AFLP variation conformed to an isolation by distance model, and genetic relationships of populations, as measured by AFLP markers, were not similar to those detected in our allozyme survey.4. The lack of concordance between these two genetic marker systems probably reflects their differential responses to drift, migration, and selection occurring during this rapid invasion. Strong population structure is counter to predictions that populations of invasive species will not be differentiated, as with observations based on allozyme markers. Therefore, newly established species may require genetic surveys using multiple marker systems to evaluate population structure.

Notes: The mid-day responses of wheat ear CO2 and water vapour exchange to full-season CO2 enrichment were investigated using a Free-Air CO2 Enrichment (FACE) apparatus. Spring wheat [Triticum aestivum (L). cv. Yecora Rojo] was grown in two experiments under ambient and elevated atmospheric CO2 (Ca) concentrations (approximately 370 μmol mol−1 and 550 μmol mol−1, respectively) combined first with two irrigation (Irr) schemes (Wet: 100% and Dry: 50% replacement of evapotranspiration) and then with two levels of nitrogen (N) fertilization (High: 350, Low: 70 kg ha−1 N). Blowers were used for Ca enrichment. Ambient Ca plots were exposed to blower induced winds as well the Ca× N but not in the Ca× Irr experiment. The net photosynthesis for the ears was increased by 58% and stomatal conductance (gs) was decreased by 26% due to elevated Ca under ample water and N supply when blowers were applied to both Ca treatments. The use of blowers in the Ca-enriched plots only during the Ca× Irr experiment (blower effect) and Low N supply restricted the enhancement of net photosynthesis of the ear due to higher Ca. In the latter case, the increase of net photosynthesis of the ear amounted to 26%. The decrease in gs caused by higher Ca was not affected by the blower effect and N treatment. The mid-day enhancement of net photosynthesis due to elevated Ca was higher for ears than for flag leaves and this effect was most pronounced under ample water and N supply. The contribution of ears to grain filling is therefore likely to increase in higher Ca environments in the future. In the comparison between Wet and Dry, the higher Ca did not alter the response of net photosynthesis of the ear and gs to Irr. However, Ca enrichment increased the drought tolerance of net photosynthesis of the glume and delayed the increase of the awn portion of net photosynthesis of the ear during drought. Therefore, the role of awns for maintaining high net photosynthesis of the ear under drought may decrease when Ca increases.

Notes: 1. Knowledge of synchrony in trends is important to determining regional responses of lakes to disturbances such as atmospheric deposition and climate change. We explored the temporal coherence of physical and chemical characteristics of two series of mostly alpine lakes in nearby basins of the Colorado Rocky Mountains. Using year-to-year variation over a 10-year period, we asked whether lakes more similar in exposure to the atmosphere be-haved more similarly than those with greater influence of catchment or in-lake processes.2. The Green Lakes Valley and Loch Vale Watershed are steeply incised basins with strong altitudinal gradients. There are glaciers at the heads of each catchment. The eight lakes studied are small, shallow and typically ice-covered for more than half the year. Snowmelt is the dominant hydrological event each year, flushing about 70% of the annual discharge from each lake between April and mid-July. The lakes do not thermally stratify during the period of open water. Data from these lakes included surface water temper-ature, sulphate, nitrate, calcium, silica, bicarbonate alkalinity and conductivity.3. Coherence was estimated by Pearson's correlation coefficient between lake pairs for each of the different variables. Despite close geographical proximity, there was not a strong direct signal from climatic or atmospheric conditions across all lakes in the study. Individual lake characteristics overwhelmed regional responses. Temporal coherence was higher for lakes within each basin than between basins and was highest for nearest neighbours.4. Among the Green Lakes, conductivity, alkalinity and temperature were temporally coherent, suggesting that these lakes were sensitive to climate fluctuations. Water tem-perature is indicative of air temperature, and conductivity and alkalinity concentrations are indicative of dilution from the amount of precipitation flushed through by snowmelt.5. In Loch Vale, calcium, conductivity, nitrate, sulphate and alkalinity were temporally coherent, while silica and temperature were not. This suggests that external influences are attenuated by internal catchment and lake processes in Loch Vale lakes. Calcium and sulphate are primarily weathering products, but sulphate derives both from deposition and from mineral weathering. Different proportions of snowmelt versus groundwater in different years could influence summer lake concentrations. Nitrate is elevated in lake waters from atmospheric deposition, but the internal dynamics of nitrate and silica may be controlled by lake food webs. Temperature is attenuated by inconsistently different climates across altitude and glacial meltwaters.6. It appears that, while the lakes in the two basins are topographically close, geologically and morphologically similar, and often connected by streams, only some attributes are temporally coherent. Catchment and in-lake processes influenced temporal patterns, especially for temperature, alkalinity and silica. Montane lakes with high altitudinal gradients may be particularly prone to local controls compared to systems where coherence is more obvious.

Notes: As one of the worst invasive weeds in the world, Mikania micrantha H. B. K. spread to southern China after 1910 but without any natural enemies. Since the 1980s it has started to spread and invade widely. The weed has caused significant damage to many ecosystems in Guangdong province in recent years. This paper reviews the research in China on this weed, including its description, history of introduction together with information from morphological and physiological studies. The distribution of this invasive plant in China has been mapped and is presented together with damage being caused and analyses of soil types infested. The measures taken by the Chinese government for prevention and elimination are also discussed. Chinese scientists are now looking for effective biocontrol options to deal with this deleterious plant. Several native insects, mites and fungi have been reported to be able to control the reproduction of this weed in China, but no natural control has been achieved. Cuscuta sp., a native autoecious vine has recently been shown to suppress the growth of M. micrantha. Three major causes for the massive spread of this weed in southern China are presented together with recommendations for future control activities.

Notes: Saccharomyces cerevisiae strains lacking a functional Pho85 cyclin-dependent kinase (cdk) exhibit a complex phenotype, including deregulation of phosphatase genes controlled by the transcription factor Pho4, slow growth on rich media, failure to grow using galactose, lactate or glycerol as a carbon source and hyperaccumulation of glycogen. The ability of Pho85 to regulate the transcription factor Pho4 is mediated by its association the Pho80 cyclin. Some other regulatory functions of the Pho85 cdk have been shown to be mediated via its interaction with a recently identified family of Pho80-related cyclins (Pcls). Here, we show that the poorly characterized Pho80-like protein Pcl7 forms a functional kinase complex with the Pho85 cdk, and that the activity of this complex is inhibited in response to phosphate starvation. Additionally, we show that Pcl7 interacts with the phosphate-regulated cyclin–cdk inhibitor Pho81, and that the regulation of the Pcl7–Pho85 complex in response to changes in phosphate levels is dependent on Pho81. Thus, we demonstrate for the first time that the Pho81 regulator is not dedicated to regulating Pho80, but may act to co-ordinate the activity of both the Pho80–Pho85 and Pcl7–Pho85 cyclin–cdk complexes in response to phosphate levels. We also demonstrate that expression of Pcl7 is cell cycle regulated, with maximal activity occurring in mid to late S-phase, perhaps suggesting a role for Pcl7 in cell cycle progression. Finally, we describe the phenotype of pcl7Δ and pcl6Δ yeast strains that have defects in carbon source utilization.

Notes: Divergence between two eastern Pacific forms of Triphoturus, currently considered to belong to the same species was tested by DNA sequences of the cytochrome b gene (DNA obtained from larvae collected in northern Chile and from adults in the Southern California Bight) and examination of larval characters. The number of apparently fixed substitutions (12 among 31 variable sites, out of 1001 bases) was high and the pattern of mid-lateral trunk pigmentation in larvae also differed consistently between the two forms. The results support the separate species status for T. mexicanus(North America) and T. oculeus(Central-South America).