Participation in the XV International Symposium On Chironomidae, St Paul, Minnesota, And Study Tour To Washington State University

Abstract

This report summarises activities, findings and recommendations arising from overseas travel between Sunday 10 August and Monday 25 August 2003, during which time I spent approximately 5 days participating in the XV International Symposium on Chironomidae in St Paul, Minnesota, 2 days at the Washington State University Department of Entomology faculty meeting at Mt Vernon, and 7 days at the Washington State University Research Centre, Prosser. This trip has placed me in a better position to develop and deliver research programs designed to maintain the NSW agricultural industries at the forefront of both productivity and environmental sustainability. Specific recommendations arising from the travel include: Ø The development of research proposals aimed at determining the selectivity of rice bloodworm control treatments to Chironomus tepperi, the principal pest species attacking rice in NSW. Many of the bloodworm control treatments currently in use are likely to be killing a broad range of aquatic insects that are actually beneficial to the crop. Farmers have chosen these treatments in preference to more advanced approaches for many years, primarily due to their low cost, however in so doing they have potentially had a detrimental effect on invertebrate food chains within the rice agroecosystem. Because of the importance of aquatic food sources to terrestrial food chains, growers may obtain a greater benefit from more selective materials which, although potentially more expensive, may allow better conservation of non-target species. This will lead to higher incrop biodiversity and ultimately greater populations of both aquatic and terrestrial predators that will provide better natural control of pests such as mosquitoes and armyworms. Ø Invertebrate research programs in rice, conducted either for pest management or environmental assessment purposes, need to have a greater emphasis on community ecology and structure, rather than on just the populations of pest or indicator taxa responding to chemical applications. The multivariate analysis tools necessary or looking at community structure (multidimensional scaling, detrended correspondence analysis, etc) are now readily available in desktop statistics packages, and their use should be incorporated into all rice pest management proposals. Utilising these techniques will require additional sampling effort in field situations, and new research proposals should be prepared and resourced with these requirements in mind. Ø The development of a herbivore-induced plant volatile (HIPV) research program to evaluate the usefulness of these compounds for manipulating populations of beneficial insects in NSW crops. HIPVs are released by many crop plants in response to damage by pest species, and serve to attract predators (and potentially parasitoids) into crops that are experiencing damage. Many of the most common HIPVs have been identified by plant chemists, and studies at Washington State University have shown that lures placed in orchards, vineyards and hop-yards attract additional beneficial insects into these crops, enhancing natural biocontrol and potentially reducing the need for chemical control of pest species. Whilst HIPVs could be useful in rice crops, these materials show the greatest potential in low-input horticulture and viticulture. Grapes, citrus, and stonefruit are the most likely areas for HIPV use in NSW, however they may also be of benefit in organic agriculture and vegetable production. An initial trial program has been developed for the Yanco area, and the work will be conducted in collaboration with Associate Professor David James of Washington State University. Contacts made or renewed with other researchers at the XV International Symposium on Chironomidae (particularly Professors Arshad Ali and Xinhua Wang) are likely to lead to the development of future collaborative projects on chironomid ecology and management.