Zaprionus indiana (Diptera: Drosophilidae) in Saudi Arabia and the effect of temperature on the life cycle

Abstract

During August and November 1988 a number of drosophilid flies Zaprionus indiana Gupta 1970. were collected from the pomegranate fruit at Taif area in Saudi Arabia. The effects of 25°C, 30°C and 35°C on developmental period and survival of different stages in the life cycle of the fly were investigated at 75% relative humidity and under continuous light. The mean egg incubation period, larval and pupal duration periods and adult longevity decreased with an increase in temperature from 25°C to 30°c. However. the mean hatching percentage, larval and pupal survival, weight of adults, cumulative percentage of adult mortality were increased. The reduction in mean adult longevity at 30°C rather than 25°C was associated with great reduction in the mean oviposition period and fecundity from 35.8 :!: 12.9 to 1.3 :!: 0.9 days; and 112.5 :!: 39.7 to 1.2 :!: 0.9 eggs, respectively, and all eggs laid at 30°C failed to hatch. Most of the eggs oviposited at 25°C were laid days 11 to 25 after emergence. At 35°C only the mean larval duration period was prolonged, but the mean incubation period and larval duration period were decreased, and all pupae failed to develop to an adult. The mean generation life span was 22.4 days at 25°C, shorter than 29.2 days at 30°C.