A comparative study on some pure successive nuclei seed of Giza 80 cotton cultivar and its corresponding strains in general use [electronic resource].

Includes references.

Four successive pure nuclei of Giza 80 cotton cultivar (N) and their corresponding farmer's seeds (F) were used to evaluate and know the changes that might occur in the yield and its components, earliness and fiber properties after using the seeds by the farmers in general use. The field experiments were carried out in Minia(Env.l) and Beni-Suef (Env.2) governorates through two successive growing seasons 2011 and 2012, respectively. The genotypes mean squares were highly significant for lint percentage, seed index and earliness index as well as all fiber properties in both environments and in combined analysis. However, insignificant mean squares were obtained in both seasons among the pure nuclei for all yield traits. The greatest amount of variances of genotypes were basically due to the variances among the farmer's seeds and N vs. F for these characters indicating farmer's seeds might get genetic imperfection due to the mixture or out-crossing by off-type seeds. The interactions of genotypes by environments were detected to be highly significant for all studied characters except boll weight and earliness index. Regarding the mean performances, the results indicated that the pure nuclei surpassed farmer's strains for most studied traits except for boll weight and seed index in both environments and across data. The mean performance of the older farmer's strains (G.S0/2007) exhibited lower estimates for seed cotton yield, boll weight and earliness index at two environments and in combined. Concerning the fiber properties, the nuclei seeds of G.80 cultivar, generally, gave the best performances for most fiber properties compared with the farmer's seeds. Results also showed that seed cotton yield in farmer's seeds was positively and significantly associated with fiber fineness (rph = 0.630) and brightness% (rph=0.355) suggested that any changes when appear in these characters may be correlate with decrease of seed cotton yield. Similarly relationship . between seed cotton yield and earliness index in nuclei seeds (rph=0.621) suggested that this character can be used as an indicator for the purity and homogeneous of the strains.

Summary in Arabic.

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