Extent of genetic, variability created through biparental mating in cotton (Gossypium barbadense L.) [electronic resource].

Includes reference.

A study was undertaken in cotton (Gossypium barbadense, L) to assess the relative efficiency of biparental mating and F₃ selfed populations in realizing greater variability with desirable recombinants using F₂ of two crosses viz. (Giza 89 x PS₆) x 6022 and Giza 92 x Pima S₆ These F₂ populations were advanced to F₃ following intermating of biparental mating (BIP) and selfing. The two populations thus developed in each of two crosses were then evaluated for earliness, yield and fiber quality characters. Analysis of variance revealed highly significant differences among biparental sets of families for all studied characters. The variation between plants in biparental progenies were relatively high as compared with F₃ selfed families. Biparental progenies proved its superiority over selfing by registering high mean values in desirable direction for most characters. In general, the lower limits of range were lower for earliness characters in biparental progenies, at the same time it were high for yield and fiber characters. Considerable variation was observed in biparental progenies as compared to F₃ selfed populations for most of the characters, which confirmed by high mean genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) values. The variation created on account of biparental mating was found to be heritable as seen from increases of discrepancy between (PCV) and (GCV) and reflected less influence of environmental factors.

Summary in Arabic.

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