Estimating Genetic Parameters By Using Line × Tester Analysis For Some Faba Bean Agronomic Traits
Abstract: Five lines (females) were factorially mated with three testers (males) and the resulting F1's along with parents were evaluated in separate trials at two sites, namely Giza and Nubaria Agricultural Research Station during 2015/16 and 201/17 growing winter seasons. Each experiment was laid out in a randomized complete blocks design with three replications. Mean squares due to crosses (C), lines (L), testers (T), and line x tester (L × T) were significant for most studied traits of both sites as well as for the combined analysis. Significance of interaction variance for C, L, T and L × T with site for the same studied traits was detected. Results revealed that parents (lines Misr 3 and Misr1) and tester (X-2110) possessed the highest mean values and the best (desirable) significant and positive general combining ability effects for number of pods, seeds and seed yield per plant. This proved that these parents (lines and tester) seemed to be the good combiners for desired traits. The top-cross (Sakha1 × X-2110) gave the best SCA effects, which also recorded the highly significant and positive heterosis over mid parents for all yield components, followed by two crosses (Misr3 × X-2097 and Misr1 × X-2097) for all traits except for plant height. These three crosses could be used in the faba bean breeding program in future. Specific combining ability played the major role in determining the inheritance of all traits, revealing that the largest part of the total genetic variability associated with all traits was a result of non additive gene action. Variance ratio of general to specific combining ability (??2gca/??2sca) which was smaller than unity confirmed that dominance genetic variance was larger than additive genetic variance for all traits. Therefore, it appeared that the inheritance of all the studied traits was controlled by a preponderance of non additive gene effects. In this study, medium to low estimates of narrow-sense heritability (ranging from 66.62 to 18.79%) were observed. Selection of superior traits should be postponed to later generation, where these traits can be improved by making selections among the complete homozygous recombinants within the segregating populations.
Publication year 2018
Pages 357 – 371
Organization Name
Author(s) from ARC
Publication Type Journal
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