Diallel analysis of some important morpho-phenological traits in bread wheat (Triticum aestivum L.) crosses

Wheat (Triticum aestivum L.) is the most important food crop. It offers a great wealth of material for genetic studies due to its wide ecological distribution. The effects of GCA and SCA of morpho-phenological traits i.e. days to emergence, days to flowering, days to maturity, flag leaf length, grain filling duration, spike weight per plant, stem weight and grain yield were studied utilizing an 8×8 half diallel cross according to Griffing’s method II of Fixed model (I). Kouhdasht, Mehregan, Karim, Line 17, N-80-19, Atrak, N-92-9 and Ehsan cultivars were evaluated based on a randomized complete block design (RCBD) with two replications at the research farm of Gonbad Kavous University during fall 2017-2018. The analysis of variance and effect of SCA were significant for all the characters which showed a significant variability among their parents for all studied traits. The analysis of variance indicated that the effect of GCA was significant for all traits except for days to maturity and grain filling duration (p≤0.05). The obtained results from the mean square ratio of GCA to SCA showed that non-additive genetic variance played a predominant role in the inheritance of most traits. Based on GCA and SCA effects obtained from biplot analysis on 8 parents, N-92-9×Ehsan, N-92-9×Kouhdasht, Mehregan×Atrak, Ehsan×Line 17, N-80-19×Mehregan and Karim×Karim were detected as the best hybrids for grain yield. Further studies in relation to the agronomic traits, can improve our knowledge about the wheat cultivars used in the present study and can direct future breeding programs.