Genetic variation for tolerance to post-emergence herbicide,imazethapyr in lentil (Lens culinaris Medik.)

Weeds pose a serious constraint to lentil production. Identification and deployment of post-emergence herbicide tolerance in improved varieties can help reduce the production cost and increase the productivity and area under lentil cultivation. Imazethapyr, a post-emergence herbicide was tested on 180 lentil genotypes for two consecutive years. Significant variation among the genotypes was observed for tolerance to imazethapyr. On a 1–5 scale, 12 genotypes were found tolerant, 46 moderately tolerant, 112 sensitive and 10 highly sensitive during the first season, and 11 genotypes were found tolerant, 51 moderately tolerant, 110 sensitive and 8 highly sensitive during the second season. Based on the first year’s result, 30 genotypes, representing tolerant, moderately tolerant, sensitive and highly sensitive reactions, were evaluated to determine the effect of herbicide on morpho-physiological and yield traits. The adverse effect of imazethapyr was significant on growth and yield attributes of lentils. Five genotypes namely LL699, LL1397, IPL406, EC78452 and LL1203 demonstrated tolerance to imazethapyr with limited phytotoxic effect on various morpho-physiological traits. These genotypes showed less reduction (<19%) for seed yield in imazethapyr treated plots as compared to control. These genotypes offer scope for developing post-emergence herbicide tolerant cultivars in lentil.     

Zinc-Arbuscular Mycorrhizal Interactions: Effect on Nutrient Pool,Enzymatic Antioxidants,and Osmolyte Synthesis in Pigeonpea Nodules Subjected to Cd Stress

The intent of the experiments was to analyze impact of cadmium (Cd) and/or zinc (Zn) on membrane functionality, nutrient acquisition, antioxidant defense, and osmolyte accumulation in nodules of two pigeonpea (Cajanus cajan (L.) Millsp.) genotypes (Sel 85N and P792) with and without arbuscular mycorrhizal (AM) fungus Funneliformis mosseae. Findings demonstrated that accumulation of Cd and Zn in nodules resulted in membrane destabilization, nutrient imbalance, increased antioxidant enzyme activities [superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), and glutathione reductase (GR)], and osmoprotectants such as total free amino acids (FAA), total soluble sugars (TSS), proline, and glycine betaine (GB). Cd had higher negative effects than Zn. P792 was comparatively more metal sensitive and displayed higher reductions than Sel 85N. Application of Zn decreased Cd uptake and reduced the phytotoxic effects of Cd. Zn₁₀₀₀ in combination with F. mosseae restored nodular membrane stability; enhanced nutrient pool [phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and iron (Fe)]; and boosted antioxidant enzyme activities and osmolyte synthesis in a genotype-dependent manner.     

Improvement of crop yield by phosphate-solubilizing Aspergillus species in organic farming

Phosphate-solubilizing fungal strains were isolated from organically managed soil and tested for their ability to solubilize rock phosphate (RP), ferric phosphate and aluminium phosphate. These strains were identified as Aspergillus tubingensis and Aspergillus niger based on internal transcribed spacer sequence analysis. A field study was conducted in two different seasons in organically managed soil to test the efficacy of two strains, A. tubingensis (PSF-4) and A. niger (PSF-7) on the yield and soil fertility. RP was amended at the rate of 59 kg P₂O₅ ha^?1 to study the effect of RP on soil fertility. The maize was grown in rainy season (July–October 2011) and wheat in winter season (November 2011–April 2012). Plant heights, shoot and root dry biomass and phosphorous (P) uptake in roots, shoots and grains were significantly increased due to inoculation in both crops. The yield of maize and wheat were significantly increased when inoculated along with RP fertilization. Organic carbon, P levels and soil enzyme activities were significantly increased due to inoculation. Results of present study suggested that A. tubingensis and A. niger improved the crop yield and soil fertility of organic farm when inoculated with RP fertilization.     

Morpho-physiological evaluation of Elymus semicostatus (Nees ex Steud.) Melderis as potential donor for drought tolerance in Wheat (Triticum aestivum L.)

Genetic Resources and Crop Evolution - Gradual deterioration in water resources and unpredictable distribution pattern of annual precipitation amount are major threats having drastic effects on...