Association of Stability Parameters and Yield Stability of Sesame (Sesamum indicum L.) Genotypes in Western Ethiopia

Abstract

Information on phenotypic stability is useful for the selection of crop varieties as well as for designing  appropriate breeding strategies. The present study was designed to determine the stability of sesame genotypes for seed yield and to elucidate interrelationships among the stability parameters and their  associations with mean seed yield. Ten sesame genotypes were tested in four locations in 2011 and 2012 crop  seasons using a randomized block design, with three replications. Nine statistical methods were used to  determine seed yield stability of the sesame genotypes. The results of the various statistical analyses showed  significant variations in seed yield due to genotype, location, and genotype x location interaction. Mean and  cultivar superiority performance (Pi) showed high correlation with yield. Cultivar superiority measure (Pi) was  significantly associated with S1 and S2. The positive correlation between Wricke and Shukla was perfect and  the two procedures are equivalent for ranking purposes. Hence, either Wricke or Shukla can be used. Nassar & Hühn’s absolute rank difference (S1) and variance of ranks (S2) were correlated positively and highly  significantly (r = 0.99**), hence either of them can be used. The correlations among the stability parameters  S2di, Wi, ..2i, ASV, S1 and S2 were positive and significant. Two genotypes, viz., EW002 and BG006, have  been identified as stable with high mean seed yield and could be recommended for western Ethiopia. It could be  concluded that both seed yield and stability should be considered simultaneously to exploit the useful effect of G x E interaction and using non-parametric stability measurements as an alternative to parametric stability measurements is important. Keywords: Genotype; G x E Interaction; Sesame; Stability; Yield