Seasonal Incidence of Sesame Webworm, Antigastra catalaunalis (Dup.) and Evaluation of Selected Cultural Control Practices, on Sesame Crop in Erbil City

Abstract

Background: Sesame Webworm, Antigastra catalaunalis (Dupunchel) is a principal harmful insect of sesame crop. It infests the all shoot parts and stages of sesame plant growth and responsible for approximately seventy percent seed yield loss, therefore, the present study conducted to investigate the seasonal incidence and evaluate two sets of cultural control practices against the damages of the pest larvae. Methods: Field experiment was carried out in the Grda Rasha Research Station-College of Agricultural Engineering Sciences-Erbil-Kurdistan region-Iraq, apart from seasonal incidence, first Set was for assessing the effect of three Sowing Dates viz. 16-May, 15-June, 15-July-2020. The second set was for evaluating the efficiency of three different crop plants viz. corn, cowpea and sunflower plants, intercropped with sesame crop to minimize the capsule infestation damage and seed losses caused by A. catalaunalis (Dup.). The experiments were performed using the RCBD design. Result: The results revealed that the larvae appearance started 2 weeks after sowing and reached its peak 2.31, 2.50 and 2.83 larvae/plant 13 weeks after sowing for all three dates of sowing, the results also showed that the percent capsule infestation and Seed weight loss/25 capsules were 22.27%, 33.85% and 34.16%/25 capsule of sesame plant, for sowing dates mid-May and mid-June and Mid-July respectively. The findings of the intercropping experiment revealed that the least percentages of capsule infestation and losses in seed weight/25 capsules were on sesame plants intercropped with cowpea 18.00% and 21.00% and followed by sesame intercropped with Sunflower and Sesame plants intercropped with corn plants which were 19.40%, 25.60% and 20.20%, 27.60% respectively.