Beetle Allies for Australian Vegetable Growers

Vegetable crops are attacked by a wide variety of pests, including whiteflies, leafhoppers, leafminers, flies, thrips and aphids, which can, if not properly controlled, devastate crops. Currently, growers rely on insecticides to manage their pests. However, there are many instances when pests are present, but not at levels that threaten crop yields, due to the action of natural enemies – predators and parasites. These beneficial insects can provide the important ecosystem service of pest control with the resultant indirect benefit of reducing the use of insecticides. Two voracious predators that are commonly found in vegetable crops in Australia are the red and blue beetle, Dicranolaius bellulus and the striped ladybird, Micraspis frenata. A recent experiment conducted by the CSIRO showed that a single red and blue beetle, on average, eats up to 39 melon aphids per day, while a striped ladybird eats up to 60 melon aphids per day.