Combing Ability for Seed Yield and Agronomic Traits of Sesame Genotypes (Sesamum indicum L.) from Western Ethiopia

Abstract

Knowledge of the genetic control of characters is essential for breeders to decide on the breeding procedure to follow. The aim of this study was to  determine the nature of gene action in the inheritance of major quantitative traits in sesame. Ten parents of sesame were crossed in year 2011 in a 10 x  10 full diallel mating system. Data were collected for major agronomic traits, grain yield and oil content. F₁ progenies along with their parents were  evaluated during 2012 cropping season in a randomized complete block design with three replicates at Uke and Wama trial sites of Bako Agricultural  Research Center. For all traits, general (GCA) and specific (SCA) combining abilities were highly significant. Mean square for reciprocal effects were  significant for all traits except plant height. Inbred lines Dicho, EW002, BG006, Obsa and EW003-1 had positive GCA effects for seed yield per plant.  Parental line BG006 had high GCA for oil content. For seed yield per plant, direct crosses BG006 x EW003-1, EW023-2 x Wama, EW003-1 x EW019 and  EW003-1 x EW010-1 had high SCA effects, while EW019 x Dicho and Obsa x Dicho had high SCA for oil content. For seed yield per plant, reciprocal crosses  EW010-1 x EW002, EW006 x BG006, EW003-1 x EW023-2 and Dicho x EW006 were good combiners. Reciprocal cross Wama x EW019 was the best for its  high SCA for oil content. The predominance of non-additive gene actions in all traits considered in this study suggested the exploitation of hybrid vigor as  the best approach in sesame breeding. The result of this experiment indicated that maternal effects were important in sesame breeding for high seed  yield.