Growth environment effect on phenology, agroclimatic indices, symbiotic parameters and yield of kharif mungbean [Vigna radiata (L.) Wilczek] genotypes

A field experiment was conducted during kharif (rainy season) 2014 and 2015 at the research farm of Punjab Agricultural University, Ludhiana, Punjab to study the effect of growth environment in terms of five dates of sowing (1, 10, 20, 30 July and 10 August) on phenology, agroclimatic indices, symbiotic parameters and yield of four genotypes (ML818, PAU 911, ML2037and ML2056)ofmungbean. The highest grain yield was recorded under 20 July sowing, which was statistically at par with that in 30 July sowing but significantly higher than all other dates (1 July, 10 July and 10 August sowings). Sowing around 20 July resulted in realizing higher grain yield by 79.1, 43.1, 4.2 and 36.8 per cent over that in 1 July, 10 July, 30 July and 10 August sowing in 2014 and 17.6, 13.8 and 4.7 per cent over 1 July, 10 July and 30 July sowing in 2015, respectively. The plant height decreased with delay in sowing. Mungbean sown on 20 and 30 July recorded significantly higher number of pods/plant, seeds/pod and 100-seed weight in comparison to other dates. Mungbean sown around 20 July provided the highest nodule number & nodule dry weight, gross, returns, net returns and B: C ratio which was followed by 30 July sowing. Days to 50% flowering & maturity, accumulated growing degree days and photothermal units were reduced with delay in sowing. The genotypes, ML 2037 and ML 2056, recorded higher grain yield, which was significantly higher than ML 818 and PAU 911. Genotype ML 818 took the highest number of days for 50% flowering and maturity. It was concluded that last one-third period of July 20–30 is the optimum sowing time and mungbean genotypes viz., ML 2037 and ML 2056 may be preferred under Punjab conditions.