Insect Life Cycle Modelling (ILCYM) software - a generic platform for developing insect phenology models, population analysis and risk mapping.

Abstract

Abstract Insect Life Cycle Modelling (ILCYM) software is an open-source computer-aided tool built on R and Java codes and linked to the uDig platform, which is a basic geographic information system (GIS). The software package consists of three modules: (i) the 'model builder'; (ii) the 'validation and simulations'; and (iii) the 'potential population distribution and risk mapping' module. ILCYM's model builder contains a library of several empirical linear and non-linear models, including the derivations of biophysical models, which have been proposed to define critical temperature effects in insects' development. Several statistical measures are incorporated in this module for estimation of parameters and comparison of models. The validation and simulations module demonstrates the application of the phenology models for estimating and simulating insect population abundance under constant and fluctuating temperatures. Outputs of the simulations are demographic parameters that include: (i) net reproduction rate; (ii) mean generation time; (iii) intrinsic rate of increase; (iv) finite rate of increase; and (v) the doubling time. Through these analyses, the biology and temperature requirements of insects are defined, and the effects of different diets or host plants in insects' demographic are assessed. The ILCYM-GIS component estimates three indices (the establishment risk index (EI), the generation index (GI) and the activity index (AI)) that guide in assessing the potential population distribution and abundance of a particular species. Several functionalities for vector (dbf to shape, raster to points, raster to polygons, extract by points) and raster analysis (merge, cut, mask, aggregate/disaggregate, re-class, describe, raster calculator) are part of the ILCYM-GIS component. Such features improve the manipulation of large datasets and help ILCYM's users in analysing and visualizing the risk assessment maps. The phenology model developed for the potato tuber moth Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae) a worldwide pest of potato (Solanum tuberosum L.) is used to demonstrate resulting modelling outputs.