Combining Ability and Heterosis for Seed Yield and Its Component in Linseed (Linum usitatissimum L.)

Combining ability and heterosis were calculated in linseed during 2010-11 following line ×tester design for 10 quantitative characters using six lines and three testers. The mean square for variation among parents and hybrids were highly significant for all the traits. The variation due to parents vs. hybrids was highly significant for all the characters except days to 50% flowering indicating significant heterotic response. Combining ability studies revealed that the parents Polf 17-1 and EC41528 were good general combiners for seed yield/plant and most of itscomponents, where as A195 (178) and A196 (179) were good general combiners for yield components only. Based on the comparison of mean performance, SCA effects and the extent of heterosis, the hybrids A238 (196) XEC 41528 and A72 (112) X EC 41528 appeared to be the most promising for seed yield. In general, the hybrids excelled their respective parents and the standard checks for most of the characters studied. Significant general combining ability (GCA) and specific combining ability (SCA) effects revealed meaningful contributions of additive and non-additive type of gene actions in governing the traits. GCA/SCA found less than 1 revealed the importance of non-additive gene action in the inheritance of all the traits and stresses the need for its exploitation either through heterosis breeding programme.