Combining ability for drought tolerance and yield in blackgram

Abstract

A research programme consisting of five drought tolerant lines, three high yielding testers and their fifteen hybrids was carried out at the Department of Plant Breeding, College of Agriculture, Vellayani, during 1996-97, to evaluate the combining ability and gene action for drought tolerance, yield and related characters in blackgram. The lines and testers were selected based on previous performance and crossed and subjected to line x tester analysis and data recorded on both yield and drought related characters. Significant difference among the treatments was observed for all characters. Differences among parents were observed for all characters except number of branches per plant and number of pods per plant. Crosses were significantly different for all the characters. Therefore combining ability analysis was carried out for all characters. Specific combining ability variance was significant for all traits except number of branches per plant indicating the importance of non additive gene action. Both additive and non additive gene action were found to be involved for duration of the crop, number of pods per plant and grain yield per plant. However in all cases non additive gene action was predominant. Among lines, T 9 emerged as the best general combiner for various yield and drought related characters. The line, CoBG 302 was also found to be a better general combiner for various characters. Among testers, WBG 67 proved to be the best general combiner followed by VB 11. No specific cross combination was found to be significantly different for all the traits together. However the cross PDU 101 x WBG 67, CoBG 302 x CoBG 303 and T 9 x

VB 11 were found to be the better specific combiner, when all the characters are considered. In short on the basis of combining ability estimated the lines T 9 and CoBG 302? the testers WBG 67 and VB 11 and the hybrids PDU 101 x WBG67, CoBG 302 x CoBG 303 and T 9 x VB 11 were suggested for further utilization for improvement.