Damage and Loss Due to Broad Mite on Different Growth Stages of Seasame

Abstract

Broad mite : Ployphagotarsonemus latus Banks is a little pest animal which infest potato, tomato, chillie, cotton, mango and sesame. It moves as a clump into terminal bud and systemic sap below of an adacial leaves, that makes sesame have short node and stunt which 100% cause damage. Then assessment of broad mite damage was taken on different growth stages to gain information on the most susceptible period of sesame growth stages and plan for spray pesticide application, Planting white sesame Mahasarakam 60 to be at 3 growth stages namely vegetative growth (seedling-before flower), flower (first bloom-before pod) and (first pod-harvest) whithout any insecticide application in June, July and August respectively. Studies were made during April-October in 2000-2001. Number of broad mites was counted under stereo microscope once a week, and was abundantly found on the adacial of sesame leaves at 35-42 days after emergence (pod growth stage). Number of broad mites in August was more than in July and June. Then white sesame should not be grown to have pod growth stage or age 35-50 days in August.