Plant age effect of rice cultivar IR46 on susceptibility to the yellow stem borer Scirpophaga incertulas (Walker) (Lepidoptera: Pyralidae)

Abstract

Plant damage and grain yield losses of rice cultivar IR46 under field conditions were highest when attacked by yellow stem borer Scirpophaga incertulas (Walker) larvae in the tillering and flowering stages and lowest when plants were at the panicle initiation stage of growth. A screenhouse tests indicated that S. incertulas development was most rapid on the tillering and flowering stages and lowest on the panicle initiation stage. An action threshold of one egg mass per m2 is suggested. © 1987.