PARASITISM AND PREDATION OF YELLOW STEM BORER, SCIRPOPHAGA INCERTULAS (WALKER) (LEPIDOPTERA: PYRALIDAE) EGGS IN TRANSPLANTED AND DIRECT SEEDED RICE

Abstract

Incidence of parasitism and predation of yellow stem borer, Scirpophaga incertulas, eggs was monitored in transplanted and direct seeded rice during March, 1984, to February, 1985. Monthly planting using the two crop establishment techniques allowed comparison of egg parasitism and predation at 29, 70, and 91 days after seeding. Parasites which emerged from yellow stem borer eggs were Tetrastichus schoenobii Ferriere, Telenomus rowani (Gahar) and Trichogramma spp. The incidence of parasitism was higher at 29 days after seeding and decreased with crop age in both methods of crop establishment. Contrarily, there was a trend toward more egg mass predation as the crop aged, especially in direct seeded rice. In general, the incidence of parasitism was higher in transplanted rice.