Australia

Whitegrubs (peanut scarabs)

Heteronyx spp

Whitegrubs are the soil-dwelling larvae of scarab beetles. The adults emerge from the soil after early summer rain to feed on vegetation and then return to the soil to lay eggs. The young larvae feed on soil humus and plant roots. Older larvae attack the shells and kernels of peanuts, reducing yield and quality. Early planted crops tend to become more infested than later planted crops

Larvae are up to 25 mm long, creamy-white with a dark head and are bent in a C-shape. Adult beetles are 7 mm long, oval and uniformly brown.

Crops attacked: Peanuts. Peanut scarab species occurs in pasture.

Damage: Young larvae feed on the roots of peanuts while older larvae attack peanut shells and kernels. Beetles feed on seedling leaves. Heavily infested crops may suffer over 30% yield loss. Damaged pods are prone to invasion by species of Aspergillus fungi, which can produce the highly carcinogenic aflatoxin