Pedigree Selection for Lint Yield in Two Segregation Populations of Egyptian Cotton (Gossypium barbadense L.)

Two cycles of pedigree selection for lint yield/plant were achieved in two segregating populations of Egyptian cotton (Gossypium barbadense L.). the genetic materials were the F2, F3 and F4 generation of the cross C.B.58 × Giza 80 (pop. I) and C.B.58 × Giza 85 (pop. II) the phenotypic coefficient of variation (CV) of lint yield/plant was large enough in the F2 generation and accounted for 55.04 and 52.68 in pop I and pop II respectively. However; the CV% of the respective parents were very low reflecting their purity. Broad sense heritability of lint yield/plant was very high (0.97) for pop I and pop II, respectively. And unreliable in the F2 generation, which resulted in high expected genetic advance of 110.35 and 105.71% from the mean) for pop I and pop II, respectively. After Two cycles of selection, the retained genetic coefficient of variability was 34.00 and 13.75 for pop I and pop II, respectively. However, the realized heritability was 0.8665 and 0.3398 for pop 1 and 0.6552 and 0.4500 for pop II in cycle I and cycle 2, respectively. In pop I the direct observed gain was significant (p<0.01) from bulk sample (35.67%) and from the better parent (27.83%). Five superior families were isolated from pop 1 and significant exceeded the better parent and bulk sample in lint yield and correlated traits. in pop II, three superior families No.351, No 169 and No 353 showed significant gain in lint yield of 15.96, 31.17 and 28.07% from the bulk sample, and 27.38, 44.09 and 40.68% from the better parent; respectively. Family No.169, showed significant (p<0.01) correlated gain from better parent of 43.38,4.15, 27.39 and 22.37% for seed cotton yield/plant, lint percentage, number of bolls/plant and boll weight, respectively.

Keywords: Cotton; Selection; Lint cotton yield