Long-term forecasts of pest pressure are central to the effective managementof many agricultural insect pests. In the eastern cropping regions of Australia, seriousinfestations of Helicoverpa punctigera (Wallengren) a...Long-term forecasts of pest pressure are central to the effective managementof many agricultural insect pests. In the eastern cropping regions of Australia, seriousinfestations of Helicoverpa punctigera (Wallengren) and H. armigera (Hiibner)(Lepidoptera:Noctuidae) are experienced annually. Regression analyses of a long series of light-trap catches ofadult moths were used to describe the seasonal dynamics of both species. The size of the springgeneration in eastern cropping zones could be related to rainfall in putative source areas in inlandAustralia. Subsequent generations could be related to the abundance of various crops inagricultural areas, rainfall and the magnitude of the spring population peak. As rainfall figuredprominently as a predictor variable, and can itself be predicted using the Southern OscillationIndex (SOI), trap catches were also related to this variable. The geographic distribution of eachspecies was modelled in relation to climate and CLIMEX was used to predict temporal variation inabundance at given putative source sites in inland Australia using historical meteorological data.These predictions were then correlated with subsequent pest abundance data in a major croppingregion. The regression-based and bio-climatic-based approaches to predicting pest abundance arecompared and their utility in predicting and interpreting pest dynamics are discussed.展开更多
文摘Long-term forecasts of pest pressure are central to the effective managementof many agricultural insect pests. In the eastern cropping regions of Australia, seriousinfestations of Helicoverpa punctigera (Wallengren) and H. armigera (Hiibner)(Lepidoptera:Noctuidae) are experienced annually. Regression analyses of a long series of light-trap catches ofadult moths were used to describe the seasonal dynamics of both species. The size of the springgeneration in eastern cropping zones could be related to rainfall in putative source areas in inlandAustralia. Subsequent generations could be related to the abundance of various crops inagricultural areas, rainfall and the magnitude of the spring population peak. As rainfall figuredprominently as a predictor variable, and can itself be predicted using the Southern OscillationIndex (SOI), trap catches were also related to this variable. The geographic distribution of eachspecies was modelled in relation to climate and CLIMEX was used to predict temporal variation inabundance at given putative source sites in inland Australia using historical meteorological data.These predictions were then correlated with subsequent pest abundance data in a major croppingregion. The regression-based and bio-climatic-based approaches to predicting pest abundance arecompared and their utility in predicting and interpreting pest dynamics are discussed.