APPLIED PEDIGREE SELECTION METHOD TO IMPROVE YIELD AND EARLINESS TRAITS FOR THREE SEGREGATION COTTON GENERATION

Using pedigree selection is useful for cotton breeding programs. However the best lines maybe include some unfavorable alleles that require making new recombination and hybridization in early segregating generations. This work was carried out at Sakha Agriculture Research Station, Agricultural Research Center, Egypt, during three growing seasons. The main objective of this investigation was to study the efficiency of pedigree selection method for F2, F3 and F4 generations derived from inter cross between cotton varieties (Giza 96 x Karsheneski-2). Were evaluated with original parents. All genotypes were evaluated for agronomic and fiber traits. The mean values were for boll weight, lint percentage, seed index, lint index and uniformity ratio traits in F4 generation were higher than the mean values of the same traits which obtained in F3 generation. Meanwhile, the mean values in F3 generation were boll maturation period, earliness index, lint percentage, fiber strength and fiber fineness traits were higher than the mean values of the same traits which obtained in F2 generation. The genotypic and phenotypic coefficient of variations(GCV and PCV) for most traits were generally larger in magnitude in F2 generation as compared with advanced generations F3 and F4, indicating that magnitude of the genetic variability persisting in this material was sufficient for improvement through selection of superior progenies for most traits. Regarding for genotypic and phenotypic correlations coefficients among yield, yield component and fiber quality traits in F4 families values between boll maturation period trait and lint percentage trait was positive significant. The results also showed that the phenotypic and genotypic correlation values were positive and highly significant between seed cotton yield and each of earliness index, lint yield and boll weight. The observed gain of yield and its components exhibited that some families such as No.1, No.20, 24 and No.34 had high yield and more earliness, Meanwhile, the observed gain values of the best five families which selected based on fiber strength were ranged from (12.50** to 14.46**%). And ranged from (-7.89** to -15.00%) for micronaire reading compared to the better parent. Also, families No.1 and 20) were high seed cotton yield and micronaire reading. Using pedigree selection and subsequently selfed pollinated can be attributed to exploitation of non-additive gene effects on accumulation of deriable alleles influencing the traits.