Genetic variability and interrelationships among earlinesscharacters, yield-related traits and fiber quality parameters in certain cotton genotypes

Abstract EN

This study aimed at assessing genotypic variability among six cotton genotypes and their 15 F₁ crosses, clarifying the relationship between cotton yield and important agronomic traits, and determining the amount of direct and indirect impacts of attributed traits on cotton yield.

Six long-staple and high-yielding cotton genotypes and their 15 F₁ crosses were evaluated in the summer season of 2017 at the Experimental Farm of Sids Research Station, Beni-Suef, Egypt.

The obtained results revealed highly significant differences among parental genotypes and their F₁ crosses for all evaluated traits.

The phenotypic coefficient of variation (PCV) was greater than the genotypic coefficient of variation (GCV) for all studied traits.

The difference between PCV and GCV was very low for days to first flower unfolding, days to first opened boll, and uniformity ratio, while was relatively higher for number of nodes to first sympodial branch, lint index, micronaire reading, fiber strength, 100-seed weight, seed yield/plant, and lint yield/plant.

The heritability in broad sense (h²_b) values were high for days to first flower unfolding, days to first opened boll.

Moreover, number of opened bolls/plant and boll weight/plant had positive and significant genotypic and phenotypic correlation with seed yield/plant and lint yield/plant.

Furthermore, number of opened bolls/plant, boll weight/plant, and 100-seed weight exhibited positive direct effect on seed cotton yield.

The highest indirect effects on seed cotton yield were assigned for number of opened bolls/plant, boll weight/plant, 100-seed weight, lint percentage, and lint index through lint yield/plant.

The obtained results provide valuable information for cotton breeding programs to develop new high-yielding genotypes with acceptable fiber quality parameters