ABSTRACT

Developmental periods of the coccinellid, Exochomas flavipes were estimated at constant temperatures between 18.5 and 32.3 ‘C. Rearing this predator was conducted on Myziss persicae as prey. For each stage, a fitted equation for the developmental rate-temperature relationship was determined. For all immature stages, as well as for total developmental period, this relationship is linearly in the tested range of temperature. The lower threshold temperature (Tt) for development and the thermal constant (K) were estimated. It was found that Exochomsss flavipes required an accumulated 226 degree-days (K) over a threshold of 11.4 ‘C (Tt) for total development. This result was in harmony with that reported for other coccinellid species. The functional relationship between lower threshold temperature and sum of effective temperature predicts a 0.22 ‘C decrease in Tt per 10 degree- days decrease in K.