DefinePK

Abstract

ABSTRACT Acolesthes sarta Solsky is and important borer of poplars, chinar and several other species and widely distributed in Pakistan. Beetles measuring 35 mm (female) and 32 mm (male) emerge from 20th March to 15th April with peak emergence during 1st to 10th April. They mate in 8 hours to 2 days after emergence with a copulation period of 5 to 25 minutes. Longevity of males is 7 to 15 days while females live for 19 to 25 days. While elliptical eggs measuring 3.1to 4.9 mm are laid in clusters 1 to 5 emergences usually at night in wounds and cracks on poplar stems. On an average a female lays 156 eggs with a maximum of 231 eggs at 22 to 240C and a minimum of 22 eggs at 150C under laboratory conditions. Yellowish white grubs, 5.4 mm long hatch after 10 to22 days and start eating out galleries just beneath the bark. Older grubs make 2 to 7 cm broad and 19.3 cm long galleries deep into the stem. Full grown grubs 5.6 cm long transform to 3.6 cm long whitish yellow pupae after preparing pupal chambers. It completes one life cycle in two years. It spends one month in emergence, 22 days in egg laying and incubation, 17 to 18 months as grubs, 17 days as prepuae, 3 to 4 months as pupae and 1 to 2 months as premature beetles lying kin pupal chambers.