Forecasting the favourableness of the Australian environment for the Russian wheat aphid, Diuraphis noxia (Homoptera: Aphididae), and its potential impact on Australian wheat yields

Abstract

AbstractThe CLIMEX model for matching climates in ecology is used to forecast the favourableness of the Australian environment for Diuraphis noxia (Mordvilko). Parameters used in CLIMEX for D. noxia were derived from the literature and tuned by iterative matching with the known distribution of the aphid in North America. These fitted values were then validated using the known distribution of D. noxia in southern Africa, and with the country-by-country occurrence of the aphid around the world. The results suggest that the drier inland parts of the Australian wheat belt would be very favourable for D. noxia growth and survival. A computer model of the interactions between climate, wheat growth and the biology of D. noxia was then used to simulate the likely infestation rates and potential yield reductions at selected sites in both the summer and winter rainfall regions of the Australian wheat belt. The results indicate that D. noxia has potential to cause severe losses to the wheat crop should it arrive in Australia.