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1. The stem borer (Scirpophaga incertulus) is a major pest of rice and distributed throughout the region. The female moth has bright yellowish brown fore wings with a black spot on each and an anal tuft of yellowish hairs.
2. The males do not have the black spot on the fore wings. Eggs are laid near the tip of the leaves covered with buff coloured hairs. Each egg mass contain 20-25 eggs and a female lays 3-4 such egg masses.
3. Incubation period ranges from 6-8 days and the newly emerged larvae enter the leaf sheath. From there they bore into the plant near the nodal region. The larvae reach the full growth in 30-40 days and the final instar larva measures 2 cm long.
4. Pupa is dark brown and the pupal period varies from 6-10 days.
5. The larva feeds inside the stem causing death of the central shoot or dead heart in young plants and 'white ear' in panicle stage.
6. The percent damage ranges from 12-15%. The female moths are highly attracted to light at night. Entomopathogenic nematodes (mermithids), entomogenous fungi (Beauveria velata, B. bassiana) and hymenopterian parasitoids (Tetrasticus sp.) are the common natural enemies, which occur in rice ecosystem.