Insect Pests of Fruit, Plantation, Medicinal & Aromatic Crops (2+1)

1. White grub - Holotrichia insularis Brensk. (Melolonthidae: Coleoptera)

Damage

• The grub feeds on rootlets causing withering and drying of young plants.
• In case of severe, attack the entire seedling is killed.
• The adult beetles feed on leaves causing severe defoliation.
Bionomics

• The adult beetles are brownish black in colour.
• The beetles emerge from the soil with the onset of monsoon during June-July.
• It lays shiny white, oval shaped eggs in the soil. The egg period is 8-12 days.
• The young grub feeds on roots of host plants the grown up grub is white, fleshy, 'C' shaped. The grub period is 55-80 days.
• It pupates in earthern for 8-12 days.
• It hibernates in pupal stage from November-June and later on emerges as adult.