Genetic analysis of adaptive and physiological traits in response to high temperature stress in rapeseed

Abstract

Diallel populations of rapeseed consisting of three yellow sarson (B9, YSH401 and NRCYS05-03) and two toria (Jeuti and TS46) parental lines were used for studying the genetic variation for physiological traits in response to high temperature screened under temperature gradient tunnel. Significant variation was observed for all traits in stress environment. Parents Jeuti and TS46 along with the crosses B9 x Jeuti, YSH401 x TS46, NRCYS05-03 x Jeuti and NRCYS05-03 x TS46 were found promising based on mean performance for yield attributing characters under stress condition. YSH401 was a good general combiner for heat susceptibility index and B9 x YSH401, B9 x TS46 and YSH401 x Jeuti were observed as heat tolerant. Main shoot length, number of flowers on main shoot, number of siliquae on main shoot, siliqua density, percent flower drop, number of siliquae on terminal shoot, biological yield per plant and seed yield per plant showed high genetic variation with high heritability and genetic advance. Number of flowers on main shoot was positively correlated with siliquae on main shoot and seed yield per plant.