Triallel analysis for yield components and fiber traits in Gossypium barbadense l [electronic resource].

Includes reference.

The aim of this investigation is to determine combining ability estimates for yield and yield components traits and some fiber properties in cotton. The genetic materials used in the present study included five cotton varieties and their 30 three-waycrosses. All these varieties belong to the species Gossypium barbadense L. In 2006 growing season, these genotypes were evaluated in a field trial experiment at Sakha Agricultural Research Station, Kafr El-Sheikh Governorate. The following traits were estimated: seed cotton yield/plant, lint yield/plant, boll weight, number of bolls/plant, lint percentage, fiber fineness, fiber strength, upper half mean and uniformity ratio %. The results showed that the performances of most the three-way crosses were as good as or better than their both grand parents or/and their third parent. The mean squares of genotypes were significant or highly significant for all studied traits. From the analyses of triallel crosses, the results revealed that the variety Giza 86 was the best combiner for yield and yield components traits as a parent and /or a grand parent as well as TNB1 as parent and/or grand parent and Giza 85 was a good combiner as parent and/or grand parent for most fiber properties .Therefore, these parental varieties could be utilized in a breeding program to improve these traits through the selection in segregating generations. The results also investigated that the hybrids [P₁x P₃] X P₄, [P₁x P₄] X P₅, [P₁ x P₅] X P₄, [P₂ x P₃] X P₅, [P₂ x P₅] X P₄ appeared to be the best promising for breeding toward all studied yield traits potentiality. Meanwhile,[P₁ x P₂ ]x P₅ ,[ (P₃) X [P₄ ]x P₅ would be the best for all studied yield traits and upper half mean (UHM) property. In addition, the combinations [P₁ x P₅ ] X P₃, [P₂ X P₄ ] X P₃ appeared to be the best promising for fiber strength (F.S.) property. Most of these combinations at least involved one of the best general combiners for yield.The results also showed that the fiber properties and yield components were mainly controlled by additive variance and /or additive x dominance epistatic variances. The results also. cleared that the calculated values of heritability in broad sense ranged from 96.00% to 99.73% for fiber strength (F.S.) and seed cotton yield/plant (S.C.Y./P.), respectively. In the same time, narrow sense heritability ranged from 0.79% to 21.33% for lint percentage (L.%) and seed cotton yield/plant (S.C.Y./P.),respectively.

Summary in Arabic.

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