ALBERT

Description: SUMMARYTo upgrade the use of permanent grasslands in livestock farming systems for their economic and environmental utility, their value needs better assessment in terms of both quantity (biomass production) and quality (nutritive value: organic matter digestibility (OMD) and crude protein content (CP)). The wide variability in permanent grassland botanical composition makes it important to understand the links between vegetation characteristics and permanent grassland value, and how far environmental factors influence this value. The current work investigated how vegetation characteristics and weather explained the variability of the biomass production and nutritive value of permanent grasslands. Two models were used to determine the best vegetation characteristics for the prediction: (i) plant functional types (PFT), proportions of grasses, legumes and forbs and weather, and (ii) two proxies for PFT (dry matter content (DMC) and phenological development at medium plant stage (MPS)), proportion of grasses, legumes and forbs, and weather. The study was conducted on a set of 190 permanent grasslands distributed over a wide range of soil, climatic and management conditions, and lasted 2 years (2009/10). For each of the permanent grasslands, climatic data, values of vegetation characteristics, biomass production and nutritive value were collected at the beginning and end of spring, and during summer and autumn regrowths. Contribution of weather was important and particularly for regrowths. Composition in terms of botanical families, plant stage and sward DMC was the common variables that explained both biomass production and nutritive value during the growing season. Biomass production was mainly explained by the proportion of legumes and forbs, MPS and DMC considering both models. Grass nutritive value was linked to the same factors, including PFT. However, the contribution of grass PFTs was lower in models. Both models could be used to predict biomass production and nutritive value:R2of the two models are quite similar. Over a wide range of environmental and management conditions, vegetation characteristics and climatic data explained almost half of the variance of forage quality and 20–40% of the variance of biomass production.

Description: SUMMARYMost crop models make use of a nutrient-balance approach for modelling crop response to soil fertility. To counter the vast input data requirements that are typical of these models, the crop water productivity model AquaCrop adopts a semi-quantitative approach. Instead of providing nutrient levels, users of the model provide the soil fertility level as a model input. This level is expressed in terms of the expected impact on crop biomass production, which can be observed in the field or obtained from statistics of agricultural production. The present study is the first to describe extensively, and to calibrate and evaluate, the semi-quantitative approach of the AquaCrop model, which simulates the effect of soil fertility stress on crop production as a combination of slower canopy expansion, reduced maximum canopy cover, early decline in canopy cover and lower biomass water productivity. AquaCrop's fertility response algorithms are evaluated here against field experiments with tef (Eragrostis tef (Zucc.) Trotter) in Ethiopia, with maize (Zea mays L.) and wheat (Triticum aestivum L.) in Nepal, and with quinoa (Chenopodium quinoa Willd.) in Bolivia. It is demonstrated that AquaCrop is able to simulate the soil water content in the root zone, and the crop's canopy development, dry above-ground biomass development, final biomass and grain yield, under different soil fertility levels, for all four crops. Under combined soil water stress and soil fertility stress, the model predicts final grain yield with a relative root-mean-square error of only 11–13% for maize, wheat and quinoa, and 34% for tef. The present study shows that the semi-quantitative soil fertility approach of the AquaCrop model performs well and that the model can be applied, after case-specific calibration, to the simulation of crop production under different levels of soil fertility stress for various environmental conditions, without requiring detailed field observations on soil nutrient content.

Description: SUMMARYSixteen Suffolk lambs with 29 ± 2·0 kg body weight were housed in individual cages for 60 days and allotted to four treatments in a completely randomized design to determine the effect of administration ofSalix babylonica(SB) extract and/or exogenous enzymes (ZADO®) on lamb performance. Lambs were fed with 300 g/kg concentrate (160 g crude protein (CP)/kg, 13·4 MJ metabolizable energy (ME)/kg dry matter (DM)) and 700 g/kg maize silage (80 g/kg CP, 11·7 MJ ME/kg DM) as a basal diet (control). Another three treatments were tested; the SB extract was administered at 30 ml/day (SB) and exogenous enzymes ZADO®(i.e. an exogenous enzyme cocktail in a powder form) directly fed at 10 g/day (EZ), while the last treatment contained ZADO®at 10 g/day + SB extract at 30 ml/day (EZSB). Lambs of the treatment EZSB had the greatest average daily weight gain (ADG) and feed conversion throughout the period of the experiment. However, during the first 30 days SB was more effective for ADG than EZ andvice versaduring the last 30 days of the experiment. Water consumption was greater for SB, followed by EZ and EZSB compared to the control. Intakes of DM and organic matter (OM) were the highest in EZSB followed by EZ, which had the greatest neutral detergent fibre, acid detergent fibre (ADF) and nitrogen (N) intakes. The EZSB treatment had the greatest DM and OM digestibilities compared to the other treatments; however, SB had the greatest ADF digestibility. Combination of EZ and SB had the best N balance. Allantoin, total purine derivatives (PD), allantoin : -creatinine ratio, and PD : creatinine ratio were increased in EZSB compared to the other treatments. However, EZ supplementation increased uric acid concentration, whereas the microbial N (g N/day) and metabolizable protein (g N/day) were increased in EZSBversusthe other treatments. It can be concluded that addition of 10 g ZADO®in combination withS. babylonicaextract at 30 ml/day in the diet of lambs increased feed intake, nutrient digestibility and daily gain, with a positive impact on the use of N and microbial protein synthesis.

Description: SUMMARYPredictive models for the accumulation of available phosphorus (Olsen-P, extracted with 0·5 mol/l sodium bicarbonate (NaHCO3) at pH 8·5) in the north-western arid areas of China, especially in Xinjiang, are essential for the improved management of phosphorus (P) fertilizers. In the present study, an accumulation model for Olsen-P in grey desert soil (Calcaric Cambisol) was developed using the data for initial Olsen-P in soil, P fertilizer application rate (organic and inorganic P), crop yields, and soil pH from a 22-year long-term experiment (1990–2011) with 3-year rotation of wheat (Triticum aestivum L.), maize (Zea mays L.) and cotton (Gossypium spp.). The model was also validated independently using previously published data from the literature. The results indicated an average net accumulation of Olsen-P in the plough layer (0–200 mm) of 0·36 mg/kg/year (from 0·083 to 0·47 mg/kg/year) when P fertilizer was applied, while an average net Olsen-P loss of 0·12 mg/kg/year (from 0·067 to 0·26 mg/kg/year) was observed without P fertilization in the soil. For target yields of wheat, maize and cotton at 5, 6 and 6 tonne/ha (t/ha), respectively, in soil with pH 8, the rates of Olsen-P increase in the soil as estimated by the model were 0·11, 0·24, 0·36, 0·49 and 0·61 mg/kg/year when P application rates were 60, 70, 80, 90 and 100 kg P/ha per 3-year period, respectively. For every 100 kg/ha of P surplus, Olsen-P increased by 1·1 mg/kg in Xinjiang grey desert soil. This Olsen-P accumulation model was valuable for the management of soil P in agricultural production and environmental protection in north-western China and other arid areas planted with a yearly rotation of wheat, maize or cotton.

Description: SUMMARYPythium damping-off caused byPythium aphanidermatumusually occurs in commercial nurseries of cucumber seedlings. The purpose of the present study was to develop a container medium for effectively suppressing Pythium damping-off of cucumber seedlings. Seven agricultural materials were tested for their suitability as substrates for the growth of cucumber seedlings. Bas Van Burren No. 4 peat moss (BVB) was able to promote the growth of cucumber seedlings, but it was ineffective against Pythium damping-off. Spent blewit mushroom compost (SBMC) was an available substrate that could inhibitP. aphanidermatum, but it also inhibited the growth of cucumber seedlings slightly. A cultural medium, spent blewit peat compost (SBPC), containing 50% (v/v) SBMC, 50% (v/v) BVB and 0·3% (w/v) lime was consequently formulated. The SBPC was able to promote the growth of cucumber seedlings and reduce the incidence of Pythium damping-off. A total of 20 micro-organisms were isolated from SBMC compost and screened in steamed SBPC medium for their ability to inhibit the growth ofP. aphanidermatum. Among these,Bacillus aryabhattaiisolate number CB13 was able to suppressP. aphanidermatumsignificantly in the steamed SBPC medium. Thus, bio-formulation of SBPC medium with the beneficial microbeB. aryabhattaiCB13 was carried out. The incidence of Pythium damping-off was reduced from 58% in steamed SBPC medium to 4% in the bio-formulated container medium. The novel bio-formulation has high potential for controlling Pythium damping-off in commercial nurseries.

Description: SUMMARYWater scarcity is a major constraint of agricultural production in arid and semi-arid areas. In the face of future water scarcity, one possible way the agricultural sector could be adapted is to change cropping patterns and make adjustments for available water resources for irrigation. The present paper analyses the temporal evolution of cropping pattern from 1960 to 2008 in the Hetao Irrigation District (HID), China. The impact of changing cropping patterns on regional agricultural water productivity is evaluated from the water footprint (WF) perspective. Results show that the area under cash crops (e.g. sunflower and melon) has risen phenomenally over the study period because of increased economic returns pursued by farmers. Most of these cash crops have a smaller WF (high water productivity) than grain crops in HID. With the increase of area sown to cash crops, water productivity in HID increased substantially. Changing the cropping pattern has significant effects on regional crop water productivity: in this way, HID has increased the total crop production without increasing significantly the regional water consumption. The results of this case study indicate that regional agricultural water can be used effectively by properly planning crop areas and patterns under irrigation water limitations. However, there is a need to foster a cropping pattern that is multifunctional and sustainable, which can guarantee food security, enhance natural resource use and provide stable and high returns to farmers.

Description: SUMMARYThere is an increasing interest in pasture-based dairy systems in Europe, mainly because of increasing production costs for intensive dairying. Milk is a matrix of compounds that influence nutritional and manufacturing properties, many dependent on husbandry linked to pasture-based systems (increase in pasture intake, forage : concentrate ratio, clover inclusion in swards/silages and use of alternative dairy breeds). The present study investigated the impact of three grazing-based dairy systems with contrasting feeding intensity or reliance on pasture intakes (conventional high-intensity, low pasture intake [CH], organic medium-intensity, medium pasture intake [OM], conventional low-intensity, high pasture intake [CL]) on milk fatty acid (FA) profiles, protein composition and α-tocopherol and antioxidants concentrations. The proportion of animals of alternative breeds (e.g. Jersey) and crossbred cows in the herd increased with decreasing production intensity (CH 

Description: SUMMARYSelenium (Se) is an essential micronutrient for human and animal health. Globally, more than one billion people are Se deficient due to low dietary Se. Low dietary intake of Se can be improved by Se supplementation, food fortification and biofortification of crops. Lentil (Lens culinaris Medikus subsp. culinaris) is a popular cool-season food legume in many parts of the world; it is naturally rich in Se and therefore has potential for Se biofortification. An Se foliar application experiment at two locations and a multi-location trial of 12 genotypes at seven locations were conducted from April to December 2011 in South Australia and Victoria, Australia. Foliar application of a total of 40 g/ha of Se as potassium selenate (K2SeO4) – 10 g/ha during full bloom and 30 g/ha during the flat pod stage – increased seed Se concentration from 201 to 2772 μg/kg, but had no effect on seed size or seed yield. Consumption of 20 g of biofortified lentil can supply all of the recommended daily allowance of Se. After Se foliar application, cultivars PBA Herald XT (3327 μg/kg), PBA bolt (3212) and PBA Ace (2957 μg/kg) had high seed Se concentrations. These cultivars may be used in lentil biofortification. In the genotypic evaluation trial, significant genotype and location variation was observed for seed Se concentration, but the interaction was not significant. In conclusion, foliar application of Se as K2SeO4 is an efficient agronomic approach to improve seed Se concentration for lentil consumers and there is also scope for genetic biofortification in lentil.