Regional and seasonal forecasting of the potato tuber moth using a temperature-driven phenology model linked with geographic information systems

The potato tuber moth (PTM), Phthorimaea operculella (Zeller) is an economically important and highly invasive potato pest of global proportions. Temperaturedependent phenology models are valuable for understanding pest population dynamics and implementing IPM strategies in different agro-ecological zones. This paper demonstrates the use of a phenology model developed for PTM linked with geographic information systems (DIVA-GIS) for mapping population growth potentials according to real-time or climatic average air temperature data as a tool for pest risk assessments in different agro-ecological regions and to support the development of management strategies. The likelihood of population survival
throughout the year, average numbers of generations and an activity index was computed worldwide using interpolated daily minimum and maximum temperatures at a spatial resolution of a square kilometer (WorldClim data). Alternatively,
simulations were based upon point temperature series from weather stations (1994- 2004, WMO, Resolution 40) to compute the within year distribution of risk for these specific areas. In the latter case, life-table parameters (intrinsic rate of population increase, mean generation time, net reproduction rate, immature survival etc.) were computed and visualised over time. All simulations were achieved on a daily time scale that allowed for generating summaries of population phenology and development within a defined period (i.e. cropping cycle). The approach used for the simulations of age-stage structured populations is described briefly. Possible uses and limitations of the presented model linked with GIS (pest risk mapping) in research and as a decision-aiding tool in Integrated Pest Management and policy (quarantine pest risk) are discussed.

Citation: Kroschel J and L Lacey (eds.) Integrated Pest Management for the Potato Tuber Moth, Phthorimaea operculella Zeller – a Potato Pest of Global Importance. Tropical Agriculture 20, Advances in Crop Research 10. Margraf Publishers, Weikersheim, Germany, 15-30.
South America