Combining ability over environments in wheat

摘要

The knowledge of combining ability together with per se performance of parents and hybrids over environments helps the breeders in selecting suitable parents and crosses for their use in a systematic breeding programme. In wheat, majority of workers have obtained information on heterosis, combining ability and gene action through diallel analysis and a very few have used like x tester design (Wang et al., 1985) which in turn is very fruitful when a breeder is interested to know the combining ability of several lines at a time. The present study was, therefore, undertaken to derive information on heterosis and combing ability for .grain yield and its compoentns in bread wheat (Triticum aestivum L. em. Thell) using line x tester (L x T) design. Twelve pure lines, viz. WH 291, PBW 154, WL 71 I, Raj 1482, Raj 3520, Sonalika, HD 2285, HD 2428, CPAN 3004, DL 230-6, HW 741 and UP 301 used as females were crossed with five testers, viz. WH 147, HD 2009, HD 2329, Raj 1972 and Raj 3077 to develop 60 F1 crosses during rabi 1988-89. The F1 crosses along with their parents were grown in a randomised block design with three replications at three dates of sowing (environments), i.e. 5th Nov., 30th Nov. and 25th Dec., 1989 at Agricultural Research Station, RAJ A Y, Sriganganagar (Raj). The parents and crosses were divided into two groups and were planted in the same experiment so that hybrid plots along could be considered as a separate block. When needed, pooled analysis of variance over hybrids and parents was done (Arunachalam, 1974).