Bean blossom thrips
Bean blossom thrip is a known vector of tobacco streak virus (TSV).
TSV-susceptible crops include chickpeas, cotton, mungbeans, peanuts and soybeans.
TSV also infects a wide range of weeds including parthenium weed, black pigweed, blackberry nightshade, green amaranth, and common thornapple.
Scientific name
Megalurothrips usitatus
Description of adult
Thrips are small cigar-shaped insects up to 2mm long. The adults are dark brown with a reddish tinge.
Immature stages
The nymphs or young are generally pale yellow to white. Juvenile thrips resemble the shape of adults but don't have wings.
Life history
Adults lay their eggs inside the leaf tissue. After feeding, the immatures drop from the plant and pupate in the soil. Generations are continual and populations are highest during warm and dry weather. Temperatures of around 20oC favour reproduction and survival.
Distribution
Throughout Queensland.
Host range
French beans.
Damage
Flower feeding causing twisting and curling of pods.
Control
Once in the flowers, thrips are hard to control as it is very difficult to get a registered insecticide into the flowers where the thrips are hiding.