Correlations and Path Coefficient Analysis between Leaf Chlorophyll Content, Yield and Yield Components in Cotton (Gossypium hirsutum L.) under Drought Stress Conditions

Abstract

In this study 20 genotypes, including 2 cultivars and 18 advanced cotton lines were grown under induced drought stress conditions. Twenty cotton genotypes were evaluated in terms of leaf chlorophyll content, number of boll per plant, boll weight, seed cotton weight per boll, number of monopodial branches, number of sympodial branches, 100 seed weight, plant height, ginning out turn and seed cotton yield. According to results of analysis of variance there were significant differences among the genotypes in terms of leaf chlorophyll content, seed cotton weight per boll, 100 seed weight, plant height and ginning out turn. There were significant correlations between leaf chlorophyll content, seed cotton yield (r= 0.231*) and ginning out turn (r= 0.320**), however positive but non- significant correlations were observed among leaf chlorophyll content and other investigated characteristics except for plant height and 100 seed weight. Phenotypic correlations were also partitioned into path coefficients, keeping seed cotton yield as the resultant variable and other components as causals. Path analysis revealed that leaf chlorophyll content, plant height, number of monopodial branches, ginning out turn and 100 seed weight had direct effect on seed cotton yield under drought stress conditions. Partitioning through path coefficient analysis revealed that leaf chlorophyll content may be one of the indicators in the improvement of seed cotton yield in cotton under drought stress conditions.