An estimate of losses of seed kapas and seed due to bollworms on cotton in India.
Field studies were carried out in Delhi, India, in 1970-71, to determine losses in cotton yield and quality due to damage by Pectinophora gossypiella (Saund.). Annual losses were found to be about 6525 metric tons of lint kapas (seed cotton), worth around 1216 million rupees. It was calculated that for every unit increase in the percentage of loculi damaged by P. gossypiella, there was a corresponding, statistically significant, loss in weight of seed kapas. Thus, from estimates of percentage loculi damaged throughout India, the loss in weight of kapas can, with reservations, be predicted for any location or season. The need for intensive research on the control of this pest is emphasised.