Dot immunobinding assay for the detection of bluetongue virus antibodies in sheep experimentally inoculated with bluetongue virus type 1.

Dot immunobinding assay (DIA) was evaluated for the detection of bluetongue virus (BTV) antibodies in sheep experimentally inoculated with BTV 1. Serum samples collected on 14, 21, 28, 43 and 60 day post infection (dpi) were positive for precipitating antibodies by the agar gel precipitation test (AGPT) while antibodies could be detected as early as 7 dpi by DIA and ELISA. Virus neutralizing antibodies were detected first at 14 dpi. The sensitivity of the four tests was compared on the same serum samples collected at different intervals. The results indicated that DIA was more sensitive than AGPT and the serum neutralization test and as sensitive as ELISA. Thus due to sensitivity simplicity and economy, DIA could replace AGPT for diagnosis and serological survey for BTV infection in animals.     

Phosphorus skipping effect on productivity,profitability and sustainability of rice-wheat cropping systems in Indo-Gangetic plains of India

A field experiment was conducted for eight years at ICAR-Indian Institute of Wheat and Barley Research, Karnal, Haryana, India to study the skipping effect of P application on productivity, profitability and sustainability of rice-wheat cropping system. Rice yield and biomass were 8.35% and 6.6% higher where cowpea was grown after wheat compared to rice-vegetable pea-wheat crop sequence, respectively. Phosphorus application to rice or wheat or both crops exhibited at par rice grain yield, biomass, harvest index. Phosphorus application to both crops or only in rice crop produced maximum and significantly higher wheat yield (4.62 t ha^?1) as compared to P application only to wheat (4.48 t ha^?1). Eight years growing of green gram, cowpea and vegetable pea increased the organic carbon content 42.89, 16.38 and 4.57 %, respectively compared to the initial level. Skipping of P to either crop, by considering 13.5 million ha rice-wheat area, will save approximately Rs 40,500 million (Rs = Indian rupee) or US $ 623 million ($ = Rs 65) per year. Air pollution may be checked, due to saving on diesel in transportation of P fertilizer, to the tune of 60,383 tonnes of CO₂ per year by reducing emission of one of important global warming gas.     

Productivity,profitability and sustainability of rain-fed chickpea under inorganic and biofertilization in foothills of north-west Himalayas

A 4-year (2008–2009 to 2011–2012) study was conducted on the effect of mineral phosphorus (P) + sulphur (S) and biofertilizers on rain-fed chickpea (Cicer arietinum L.) at the Punjab Agricultural University’s Research Station, Ballowal Saunkhri, India. The experiment comprised of five combinations of P and S, viz. control (P₀S₀), no P + 10 kg S ha^?1 (P₀S₁₀), 15 kg P + 10 kg S ha^?1 (P₁₅S₁₀), no P + 20 kg S ha^?1 (P₀S₂₀) and 30 kg P + 20 kg S ha^?1 (P₃₀S₂₀); and three seed inoculation levels, viz. control, Rhizobium and phosphate-solubilizing bacteria (PSB), were laid out in randomized complete block design. Combined application of P + S resulted in improved growth, nodulation, yield attributes and yield. The increase in seed yield over control due to P + S ranged from 11.8% to 17.7%. Seed inoculation with Rhizobium recorded the highest growth, nodulation, yield attributes and yield of chickpea and was statistically at par with PSB and significantly better than no inoculation. Highest benefit/cost ratio (B:C, 2.19) was obtained in P₃₀S₂₀. In view of environmental pollution and high costs of chemical fertilizers, biofertilizers alone or in combination may help to achieve sustainable and ecological agricultural production.     

一种基于聚合酶链式反应检测SNP的方法

SNP是具有广泛利用潜力的第3代分子标记,本文旨在开发一种利用PCR技术快速检测SNP的方法。设计思路是:根据已知SNP位点设计2条特异正向引物,其最后一个碱基分别与已知SNP的2个碱基相同,同时在1条引物的5′端添加1段20 bp左右的其他物种的特异序列(如细菌DNA序列),然后选择1条合适的反向引物;最后同时加入3条引物,通过梯度PCR选择合适的退火温度进行PCR反应。利用这一方法成功将玉米的ZDS基因定位在玉米第7染色体短臂7.02 Bin。这种检测SNP的方法设计简单,费用低廉,尤其适合SNP标记的分子标记连锁图构建或者基因定位。     

Bovine Leukosis II. Comparison of Hematological Classification with DNA Synthesis Between Herds

Blood samples of 126 mature cows with “persistent” hematological status from two leukosis herds and a leukosis free control herd were collected for determining hematological status and estimation of replicating lymphocytes. To quantitate the number of DNA synthesizing cells, the blood was incubated with tritiated thymidine in vitro followed by autoradiography. Classification of animals according to lymphocytosis status did not reveal clearly whether or not a difference existed between the two leukosis herds. The estimation of DNA synthesizing lymphocyte counts showed that the animals from the two leukosis herds did not differ from each other while differing significantly from control herd animals. The study suggests that the similarities between the two leukosis herds, while ambiguous on lymphocyte counts alone, become clear when DNA synthesizing cell counts are compared. Thus the animals of the two leukosis herds belonged to the same “leukosis” population.     

InfoCrop: A dynamic simulation model for the assessment of crop yields,losses due to pests,and environmental impact of agro-ecosystems in tropical environments. II. Performance of the model

InfoCrop, a generic crop model, simulates the effects of weather, soils, agronomic management (planting, nitrogen, residues and irrigation) and major pests on crop growth, yield, soil carbon, nitrogen and water, and greenhouse gas emissions. This paper presents results of its evaluation in terms of its validation for rice and wheat crops in contrasting agro-environments of tropics, sensitivity to the key inputs, and also illustrates two typical applications of the model. Eleven diverse field experiments, having treatments of location, seasons, varieties, nitrogen management, organic matter, irrigation, and multiple pest incidences were used for validation. Grain yields in these experiments varied from 2.8 to 7.2 ton ha⁻¹ in rice and from 3.6 to 5.5 ton ha⁻¹ in wheat. The results indicated that the model was generally able to explain the differences in biomass, grain yield, emissions of carbon dioxide, methane and nitrous oxides, and long-term trends in soil organic carbon, in diverse agro-environments. The losses in dry matter and grain yield due to different pests and their populations were also explained satisfactorily. There were some discrepancies in the simulated emission of these gases during first few days after sowing/transplanting possibly because of the absence of tillage effects in the model. The sensitivity of the model to change in ambient temperature, crop duration and pest incidence was similar to the available field knowledge. The application of the model to quantify multiple pests damage through iso-loss curves is demonstrated. Another application illustrated is the use of InfoCrop for analyzing the trade-offs between increasing crop production, agronomic management strategies, and their global warming potential.     

Adenylates as an estimate of microbial biomass C in different soil groups

Adenylate (i.e. adenosine tri- (ATP), di- (ADP) and monophosphates (AMP)) and microbial biomass C data were collected over a wide range of sites including forest floor layers and forest, grassland and arable soils. Microbial biomass C was measured by fumigation extraction and adenylates after alkaline Na₃PO₄/DMSO/EDTA extraction and HPLC detection. Our aims were (1) to test whether the sum of adenylates is a better estimate for microbial biomass than the determination of ATP, (2) to compare our conversion values with those proposed by others, and (3) to analyse whether soil properties or land use form affect the relationships between ATP, adenylates and microbial biomass C. A close relationship was found between microbial biomass C and ATP (r=0.96), but also with the sum of adenylates (r=0.96) within all appropriately conditioned soil samples (n=112). In the mineral soil (n=98), the geometric means of the ATP-to-microbial biomass C ratio and the adenylates-to-microbial biomass C ratio were 7.4 and 11.4 μmol g⁻¹, respectively. The mean ratios did not differ significantly between the different texture classes and land use forms. In the forest floor, the ATP-to-microbial biomass C ratio and the adenylates-to-microbial biomass C ratio were both roughly two-thirds of those of the mineral soil. The average adenylate energy charge (AEC) of all soil samples was 0.79 and showed a strong negative relationship with the soil pH (r=−0.69). However, the AEC is presumably only indirectly affected by the soil pH.     

Potato peel extract-a natural antioxidant for retarding lipid peroxidation in radiation processed lamb meat

The effective utilization of potato peel, a waste generated in large quantities by the food industry, as an antioxidant was investigated. Potato peel extract (PPE) exhibited high phenolic content (70.82 mg of catechin equivalent/100 g), chlorogenic acid (27.56 mg/100 g of sample) being the major component. The yield of total phenolics and chlorogenic acid increased by 26 and 60%, respectively, when the extract was prepared from gamma irradiated (150 Gy) potatoes. PPE showed excellent antioxidant activity as determined by beta-carotene bleaching and radical scavenging activity of 1,1-diphenyl-2-picrylhydrazyl (DPPH). The suitability of PPE for controlling lipid oxidation of radiation processed lamb meat was also investigated. PPE (0.04%) when added to meat before radiation processing was found to retard lipid peroxidation of irradiated meat as measured by TBA number and carbonyl content. The antioxidant activity of PPE was found to be comparable to butylated hydroxytoluene (BHT).     

Ordered Overlayers of C60 on GaAs(110) Studied with Scanning Tunneling Microscopy

Studies of C(60) overlayer growth on GaAs(110) with scanning tunneling microscopy show large first monolayer islands that are locally well ordered, structurally stable, and commensurate with the GaAs surface owing to molecule-substrate interactions. Within the distorted close-packed structure, two distinct adsorption sites were identified, one of them being elevated because of stress in the C(60) monolayer.