Exploring agronomic traits and breeding prospects of primary tritipyrum and triticale lines to increase grain yield potential

Abstract

A study was conducted to evaluate 13 non-Iranian primary tritipyrum (AABBEbEb, 2n=6x=42) as new amphiploid cereal derived from the hybridization of wild sand couch grass species, Thinopyrum bessarabicum (2n=4x=14, EbEb) and durum (Triticum durum, 2n=4x=28, AABB) wheat and five promising triticales for 31 different phenological and agronomic traits in a randomized complete block design (RCBD) with three replications under field conditions. The analysis of variance (ANOVA) showed significant differences between genotypes for most of the studied traits. The factor analysis results revealed five factors that almost explained 89% of the total variance. The stepwise regression and path coefficient analyses revealed that the number of grains per spike and harvest index were the most important traits contributing to the high-yield of the genotypes. Cluster analysis grouped 18 lines into three diverse genotypic clusters. Cluster III included 4115, 4116, and M45 triticale lines indicating the highest value for harvest index as well as grain yield and its components. The non-Iranian primary combined tritipyrum line, (Ka/b)(Cr/b)-5 and promising triticale line No. 4116, showed the highest values for grain-related traits, and therefore these lines may be used in further breeding programs to develop new commercial cereal hybrid/cultivars. Overall, the results indicated grain number per spike and harvest index could be utilized as the key selection criteria in breeding for improvement of grain yield in primary tritipyrum and triticale genotypes.