Abstract

Generally, all borer larvae suffer low mortality during winter. In Japan, where the winter temperature is much lower than in most other rice regions, mortality of Chilo suppressalis and Scirpophaga incertulas has been low even during severe winters. Chilo suppressalis is more tolerant of low temperatures than Scirpophaga incertulas. In years of high precipitation during autumn, higher percentages of larvae hibernate, and if the winter or spring is warm, more of these successfully pupate and emerge as adult moths. These conditions, however, also accelerate pupation and emergence.

Keywords: Rice stem; Larvae; Subtropical regions; Crop harvest;Leaf sheath; Diopsids