LAUSR

Lepidopteran stem borers are among the most important pests of maize in East Africa. Understanding the factors that influence maize stem borers' distribution is crucial in predicting their response to future climate change. The hypothesis of this study was that the potential distribution of the maize stem borers Chilo partellus (Swinhoe) (Lepidoptera: Crambidae) and Busseola fusca (Fuller) (Lepidoptera: Noctuidae) at small scale along altitudinal gradients at Mount Kilimanjaro and Taita Hills in Tanzania and Kenya, respectively, depends on other climatic and edaphic factors besides temperature. The species distribution was studied using the maximum entropy (Maxent) application with three climatic (temperature, rainfall and relative humidity) and five soil variables [soil silicon (Si), potassium (K), phosphorus (P), nitrogen (N) concentrations and water-holding capacity (WHc)]. The model accuracy was evaluated using area under the curve (AUC) values based on 25%independent test data set. The results revealed that in addition to temperature, rainfall, and relative humidity, soil characteristics were affecting the geographical distribution of C. partellus and B. fusca at both the Mount Kilimanjaro and Taita Hills study sites. The relative importance of all studied variables varied between the two study sites. At Mount Kilimanjaro, WHc exhibited the greatest influence on C. partellus distribution while at Taita Hills it was relative humidity. For B. fusca distribution, the temperature was found more crucial at both Mount Kilimanjaro and Taita Hills.