Heritability of Leaf Characteristics in Upland Cotton1

Abstract

Plants of early maturing cottons(Gossypium hirsutum L.) developed for short growing seasons generally are smaller than those plants of cultivars developed for longer growing seasons. Reduced plant size may be accompanied by altered leaf size and/or number. Information on leaf characteristics that can be genetically altered may indicate ways to enhance cotton productivity in short season environment.;. Two experiments were used to study leaf characteristics in cotton grown on the southern Great Plains. In a greenhouse experiment, three pairs of ancestral and descendant cultivars were compared for leaf traits. The descendant cultivars from two of the three pairs had significantly (P < 0.01) smaller and fewer leaves per plant. In a second experiment conducted in the field, random inbred lines from a composite cross population were used to Study the heritability of leaf size, leaves per plant, and leaf area per plant. Of the three traits studied, only leaf size displayed a significant level of genetic variability. Heritability estimates on a family mean basis for leaf size, calculated from variance components, progeny‐parent regression, and standard units were 67, 48, and 57%, respectively.