RESPONSE TO SELECTION FOR LINT YIELD IN F2 AND F3 POPULATIONS OF EGYPTIAN COTTON HYBRID

doi:10.12816/ejpb.2023.314390

RESPONSE TO SELECTION FOR LINT YIELD IN F2 AND F3 POPULATIONS OF EGYPTIAN COTTON HYBRID

Document Type : Original research

10.12816/ejpb.2023.314390

Abstract

The present study was carried out at Shandaweel Agric. Res. Sta., Sohag, Egypt, during the three summer seasons from 2020 to 2022. Two cycles of pedigree selection (in F₂ generation) and one cycle of pedigree selection (in F₃ generation) for lint yield/plant were achieved in segregating population of Egyptian cotton (G. barbadense L.) hybrid GCV% and PCV% estimates were high for lint yield/plant and accounted for 39.88, 39.91% and 30.85, 30.88% after two cycles (F₂ selection) and one cycle (F₃ selection) of pedigree selection. Broad-sense heritability estimates were very high for all studied traits in F₂ and F₃ selection. The means of selected families after two cycles of F₂ selection for lint yield/plant ranged from 41.90g for family no.176 to 81.90g for family no.162 with an average of 58.13g, while the means of the selected families after one cycle of F₃ selection for the same trait ranged from 57.70 g for a family no.195 to 81.90g for a family no. 162 with an average of 67.51 g. The average response to F₂ selection for lint yield/plant from the better parent was significant (p<0.01) and accounted for 13.15%. Six selected families showed significant direct response ranging from 10.25% for family No.190 to 59.43% for family No. 162. While, the mean response to F₃ selection for lint yield/plant from the better parent was significant (p<0.01) and accounted for 31.42% compared with 13.15% in F₂ selection. All the ten selected families showed significant direct response ranging from 12.32% for family No.195 to 59.43% for family No. 162. After two cycles of pedigree selection (F₂ selection), the coefficients of phenotypic correlation were significant and positive between lint yield and each of seed cotton yield/plant (0.99), boll weight (0.51), number of bolls/plant (0.96), lint index (0.61) and medium with lint percentage (0.39) and seed index (0.49) and low with micronaire reading (0.07) and fiber length (0.03). Also, after one cycle of F₃ selection we found high positive values of correlation coefficients between lint yield/plant and each of seed cotton yield (0.96), boll weight (0.60) and number of bolls/plant (0.78). This result revealed that all of seed cotton yield, boll weight, number of bolls, seed and lint index were the main contributors to lint yield/plant and the selection for any of these traits could increase lint yield/plant.

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