EFFECT OF TEMPERATURE ON THE POPULATION-GROWTH OF BACTROCERA-TAU (WALKER) (DIPT, TEPHRITIDAE)

The developmental thresholds and number of degree-days needed to compl ete development were determined for the immature stages and the preovi positional period of the pumpkin fly, Bactrocera tau at 6 constant tem peratures (19, 22, 25, 28, 31 and 34-degrees-C). They are (threshold/d egree-days) 9.32-degrees-C/15.75 for the eggs, 6.67-degrees-C/113.82 f or the larvae, 9.30-degrees-C/144.35 for the pupae and 8.56-degrees-C/ 180.8 for the preovipositional period. Developmental rate was related to temperature by a sigmoid curve. Gross and net fecundity, and fertil ity were greatest at 25-degrees-C, although daily fecundity and fertil ity were greatest at 28-degrees-C. Intrinsic and finite rates of popul ation increase were greatest at 28-degrees-C.