HYBRID-SEED PRODUCTION IN CYTOPLASMIC MALE-STERILE LINES OF UPLAND COTTON (GOSSYPIUM-HIRSUTUM) THROUGH INSECT POLLINATION

An experiment was conducted during rainy season of 1991 to study hybrid-seed production in 3 cytoplasmic-genic male-sterile lines of upland cotton (Gossypium hirsutum L.) by natural (insect) pollination. The study revealed the success of insect pollination, that the pollen from restorer (R) lines to male-sterile (A) lines were transferred by a number of cotton insects visiting the flowers frequently. Male-sterile and restorer lines grown in 2:1 ratio showed the highest recovery of hybrid seed/ha. Bolls/plant, boll weight, seeds/boll and F1-seed recovery/plant obtained after insect pollination were highest in 1:1 and the lowest in 4:1 ratio, whereas reverse was true for seed index.