Selection for seed cotton yield, boll weight and lint petrecentage in segregating population (giza 80 x giza 85)‎ of Egyptian cotton (gossypium barbadense l. )‎

الملخص EN

Two cycle of direct selection were accompanied with two selection intensities, i.

e, 5% and 10% one in improving seed cotton yield/plant, boll weight and lint percentage of the cotton cross Giza 80 x Giza 85.

Selection was made by one method, i.

e.

pedigree selection (PSM) from F2 to F4 generation.

Comparing mean performance of F2 with those of F3 and F4 generations revealed increase in mean values for all traits with advanced generations from F2 to F4 indicating an accumulation of increasing alleles.

F2 generation registered high GCV and PCV values than those of the succeeding generations for the studied traits.

The closer magnitude of GCV and PCV in F3 and F4
generations indicated that genotype had played greater role rather than environment for boll weight, lint percentage, number of bolls per plant and seed cotton yield per plant.

Heritability estimates in broad sense improved considerably for all traits from F2 to advance F3 and F4 generations.

The predicted advance at two selection intensities in F4 generation achieved highly genetic gain from selection for boll weight, seed cotton yield/plant and number of bolls /plant.

The results indicated that the predicted and actual genetic advances were of high values for boll weight, seed cotton yield/plant, lint percentage and bolls/ plant at both 5% and 10% selection intensity.

The selection intensity at 5% gave a highly improvement in the most selected traits in F3 and F4 generations for expected and actual genetic advances due to accumulation of useful alleles.

Families number 1, 9, 155, 29 and 156 were the best genotypes for relevant yield characters.

These families surpassed the better parent, chick varity and gave best values for most characters.

The breeder may exploit such families in breeding programs aiming to improvement yield characters.