Impact of seasons on genetic variability parameters in soybean (Glycine max (L.) Merrill)

Abstract

Soybean being a photoperiod sensitive crop usually grown during kharif season. Due to higher returns from soybean, the farmers are growing even in rabi and summer seasons. Hence, understanding genetic variability during different seasons is essential for undertaking selection during particular season. In this regard, fifteen soybean genotypes were studied at Main Agriculture Research Station, UAS, Dharwad during kharif, rabi and summer. Significant differences were observed among the genotypes for physiological, phenological, yield components, yield and quality traits in all the seasons. Higher mean was noted across soybean genotypes for chlorophyll ‘a’, days to maturity, plant height, protein content, number of branches per plant, number of pods per plant, hundred seed weight and seed yield during kharif while for oil content during rabi. Higher range was observed for SCMR, chlorophyll ‘a’, ‘b’ and total, days to initiation of flowering, days to 50 per cent flowering, plant height, number of branches per plant during summer. PCV and GCV was high for chlorophyll ‘b’, number of pods per plant, seed yield during rabi and summer. Chlorophyll ‘b’, plant height, number of pods per plant and seed yield have high heritability and GAM in all the seasons indicating the scope for phenotypic selection.