Effect of cropping system on some genetic parameters in soybean [Glycine max (L.) Merrill]

Abstract

Genetic parameters were assessed in 14 diverse genotypes of soybean grown in sole crop and as inter crop with maize. Cropping system effects were significant for all the traits, except seeds/pod. Cropping systems x genotype interaction was significant for all the traits except branches/plant and 1DO-seed weight. Both phenotypic and genotypic coefficient of variation were higher for plant height, branches/plant and seed yield in intercropping than sole crop. Genetic advance was comparable for most of the traits under both the cropping systems. The correlation coefficients, direct and indirect effects were found to differ both in nature and magnitude in sole crop and intercropping. Plant height and days to maturity showed no association with grain yield indicating the possibility to select for high yielding genotypes irrespective of plant height and maturity under intercropplng. Pods/plant followed by seeds/pod and branches/plant with higher days to flowering were important to improve seed yield under intercropping. Pods/plant followed by higher days to flowering and longer heights with lesser days to maturity were important to improve seed yield under sole crop. Genotype P8 (Himso 400 x Punjab-1) was high yielding and synchronous in maturity with maize. Separate breeding programmes are required to be undertaken for each cropping system.