Influence of Leaf Morphology on Lint Yield of Cotton—Enhancement by the Sub Okra Trait1

Abstract

Sub okra leaf (L14) is a trait in cotton (Gossypium hirsutum L.) which displays greater indentation of sinus and more lobing than does normal leaf (l). This study was initiated because previous research on the influence of this trait for lint yield or its components had been reported. In 1981, 48 populations descending from 24 crosses were initiated to compare the influence of this trait on yield relative to that of normal and two other mutant leaf types. The populations developed were from crosses of eight normal with three mutant leaf types of cotton. The eight normal leaf cultivars and strains wee ‘Deltapine 26’, ‘Deltapine 5540’, ‘Stoneville 825’, ‘SC‐I’, ‘DES 422’, ‘Tamcot CAMD‐E’, MD 69, and DES 2–10. The mutant leaf types were La 1363Lsne, La 500C, and HYC 79‐6 which possessed the super okra (L1), okra (L0), and sub okra (L14) leaf traits, respectively. Tw o populations were produced from each cross, i.e., one normal and one homozygous for the mutant leaf type. In 1982, the 48 F3 populations were grown in replicated experiments at three locations near Stoneville, Miss. Mean lint yield ranged from 870 to 1175 kg/ha for the three locations and from 927 to 1099 kg/ha for the eight sources of normal leaf types. No interactions with the eight sources of normal types were detected with environments, mutant leaf source types, or normal vs mutant types. Super okra populations averaged 95 kg/ha (8.8%) less lint yield than their corresponding normal populations. No differences in lint yield of okra vs normal leaf populations were detected, averaging 1053 and 1055 kg/ha, respectively. In contrast, lint yield of sub okra was significantly higher, averaging 47 kg/ha (4.8%) more than its corresponding normal populations. The yield superiority of sub okra over normal at the three locations ranged from 18 to 83 kg/ha. This investigation indicates a potential increase in the lint yield of cotton grown in the Mississippi Delta through the incorporation of the sub okra leaf trait.