A survey of food-plant utilization by Hemiptera (Insecta) in the understorey of primary lowland rain forest in Sulawesi, Indonesia

Abstract

ABSTRACTThe study was conducted in tropical lowland forest in the Dumoga Bone National Park, Sulawesi, Indonesia. It sought (a) to establish the typical densities of sap-sucking Hemip tera, (b) to quantify the intensity of Hemiptera feeding on leaves, and (c) to investigate, using multivariate techniques, the relationships between Hemiptera density and/or feeding damage and a range of leaf or plant characteristics. Only 3% of shrubs examined had colonial Hemiptera feeding on growing shoots. Feeding punctures on leaves were common but the insects which produced them such as the Cicadellidae and various Heteroptera were scarce. Coccoidea and Aleyrodoidea were the dominant and ubiquitous Hemipterans, feeding primarily on the surface of the leaves. Psylloidea were relatively rare and Aphidoidea were not recorded. For the complete data set, which included all leaves examined, there were few significant correlations, either singly or in combination, between the various measures of insect abundance and the state of the 17 leaf characteristics recorded. However, when the data for young leaves were extracted there was evidence to suggest that the number of feeding punctures cm−2 of leaf and the number of coccids cm−2 of upper leaf surface increased rapidly to a maximum as the young leaf aged and certain characters changed accordingly. Other more stable leaf characteristics such as hairiness, spininess, glossiness, etc. explained only a small additional amount of the total variance in Hemiptera abundance.