EXERCISE No. I PESTS OF RICE More than 100 insect species are associated with the rice crop at one stage or the other and 20 of these are pests of major economic significance. 1. Stem Borer: A. Yellow stem borer: Scirpophaga incertulas (Pyralidae: Lepidoptera) F Distribution and Status: Afghanistan, Bangladesh, Burma, Cambodia, China, India, Sri Lanka and Indonesia. F Host range: Rice F Life history: Female moth has bright yellowish brown fore wings with a black spot and a tuft of yellow anal hairs while male is smaller with pale yellow forewings without black spot. Each female lays 170-200 eggs in a mass of 15-80 on the upper surface of leaf tips covered with buff-colored hairs. The egg period 6-9 days; larva pale yellow with dark brown head, swims in water and bores in to the stem near the node. The larva migrates to other tillers also. Larval period 20-45 days, pupation in wh
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