Estimation of combining ability and it’s variances in the cultivars of bread wheat (Triticum aestivum L.)

Document Type : Original Article

Authors

Department of field Grop, College of Agriculture, Tikrit University, Iraq

Abstract

Ten of the genotypes of bread wheat ( Abu-Graib(1), Kawz (2), Osais (3), Site mall(4),   Florka (5), Kalak (6), Millan (7), Hithab (8), Ibaa 99 (9) and Sham 6 (10) were used in this study with its half-diallel crosses, all of them were planted to be (10 parents + 45 crosses) in Dialla Governorate – Blad ruz province in the ( 2017-2018) season. (RCBD) Randomized Complete Block Design was used with three replicates to study the Combining Ability for the traits: number of the days to spike formation stage, plant height (cm), leaf area (cm2), number of the grains in the spike, number of the spikes/plant, the weight of 1000 grains (g) and single plant yield (g). Analysis of variance table showed significant difference of all parents and first filial crosses in the all studied traits at (1%) level of probability and the ratio between general combining ability to specific combining ability was less than one in the traits: number of the days to spike forming, plant height, leaf area and number of the spike (m2), while in the grain number of the spike, weight of 1000 grains and single plant yield was more than one to refer to the role of the Dominance action of the genes.  The parent (Florka) showed a general combining ability for plant height, a number of the grains, and the grains yield, while the crosses (Abo-Graib X Heithab ) and (Kawz X Site mall ) showed significant differences to specific combining ability to the desired direction for more number of the traits included grain yield.

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