Study on activity areas of Exochomus nigripennis (Coleoptera: Coccinellidae) in Yazd province using Geographic Information System

In a natural ecosystem, there is a close relationship between natural enemies and environmental factors. Use of Geographic Information System (GIS) in analysis of spatial patterns of pest populations has increased during recent years. The purpose of this study was using Analytic Hierarchy Process (AHP) to determine the relationship in predatory ladybird, Exochomus nigripennis (Erichson) for biological control of the sucking pests. In order to determine the suitable areas for activity of E. nigripennis, the variables of temperature, humidity, rainfall, elevation and nutrition were selected as the most important criteria. The basis of AHP is the pair comparison of options and the possibility of examining different scenarios. ArcMap 10.1 and ArcCatalog 10.1 softwares were used to form spatial data and related analytics. The results indicated that nearly 4.34% of the province's regions, including some parts of Taft, Abarkuh and Mehriz were very good for activity and nearly 17.07% of the province's areas, such as the major part of Ardakan, Bahabad and Meybod were determined as very unsuitable for activity. Furthermore, comparison of the studied factors showed temperature with the final weight of 0.0529 is the most important factor influencing the activity of E. nigripennis and nutrition, humidity, elevation and rainfall are important in the next categories, respectively.