AU: Citrus gall wasps posing new threats to citrus growers
Heavy infestations of the Australian citrus gall wasp reduce crop yields and cause branch dieback. Severe infestations can even kill mature trees. It has a preference for grapefruit, lemons, limes and Valencia oranges, but attacks virtually all domesticated citrus species and varieties.
The original infestation in Sunraysia occurred when a Coomealla grower bought wasp-infested trees from Queensland about 20 years ago. Coomealla orchards are the worst infested – some trees have huge galls extending up to half a metre along individual branches, harbouring thousands of larvae.
The Murray Valley Citrus Board and the NSW Department of Primary Industries have been working with Dareton citrus growers Richard and Judy Bertalli for several years, to evaluate a biological control agent.
Two native parasitoid wasps deposit their own eggs into the developing gall wasp larvae, killing them before they can complete their development.
Source: sunraysiadaily.com.au
