CUCURBITS :: MAJOR :: PEST OF PUMPKIN
2. Pumpkin beetles: Aulacophora foveicollis, A. cincta, A.intermedia (Galerucidae: Coleoptera)
Distribution and status: Widely distributed in Asia, Australia, southern Europe and Africa
Serious pest
Host range: Ash gourd ,pumpkin, tinda, ghia tori, cucumber and melon.
Damage symptoms
Both grubs and beetles damage. Grubs remain below the soil surface feeding on roots, underground stems of creepers and on fruits lying in contact with the soil The adults feed on those parts of the plant which are above the ground. The early sown cucurbits are so severely damaged that they have to be resown.
Bionomics
Freshly hatched grubs are dirty white; full grown are creamy yellow, 22 mm long. Adult: A. foveicollis: red, 6.8 mm long. A. cincta: grey with black having glistening yellow-red border and A. intermedia: blue in color.
The creamy, oblong, white grubs with a slightly darker oval shield at the back lead a subterranean life and when full-grown, they measure about 12 mm in length. Adults are oblong , 5-8 mm long, beetles are found concealed in groups. In their life span of 60-85 days, they lay about 300 oval, yellow eggs singly or in batches of 8-9 in moist soil, near the base of the plants. The eggs hatch in 6-15 days. Grub period 13- 25 days and pupate in thick-walled earthen chambers in the soil, at a depth of about 20-25 cm. The pupal stage lasts 7-17 days The life-cycle is completed in 26-37 days and the pest breeds five times in a year.
Management
- Early planting of pumpkin during October – November to avoid damage by this pest
- Frequent raking of soil beneath the crop to expose and kill the eggs and grubs.
- Hand collection and destruction of infested leaves and fruits.
- Spray malathion 50 EC 750 ml, dimethoate 30 EC 500 ml, methyl demeton 25 EC 500 ml, 500 g of carbaryl 50WP in 500-750 L of water per ha or apply 7.0 kg of carbofuran. 3G per ha 3-4 cm deep in the soil near the base of the plants just after germination and irrigate.