TEMPERATURE INDUCED VARIATION IN THE RATES OF REPRODUCTIVE PROCESSES IN DENDROCTONUS RUFIPENNIS (COLEOPTERA: SCOLYTIDAE): A NEW APPROACH TO DETECTING CHANGES IN POPULATION QUALITY

Abstract

To discover measurable parameters for detecting quality differences (with respect to reproduction) in insect populations, variations in temperature were utilized to obtain manifestation of quality at different levels. Rates of reproductive and associated processes such as yolk deposition, gallery excavation, and oviposition were measured in Dendroctonus rufipennis (Kirby) at four temperatures. Information presented here allows an estimation of D. rufipennis reproduction as affected by temperature. Among the various parameters measured the length of initial egg-free gallery and the number of eggs/unit productive gallery length and yolk deposition rate could be used to discriminate bark-beetle population quality. Rates of yolk deposition appeared most useful and widely applicable for this purpose.