Effects of Constant Temperatures on Survival Rates and Reproduction of Dirhinus giffardii (Hymenoptera: Chalcididae) on Bactrocera dorsalis (Diptera: Tephritidae)

Po-Yi Tung ； Yi-Hui Wu ； Chia-Ming Liu ； Yi-Yuan Chuang

《農林學報》 68卷4期 (2021/12) Pp. 231-240

https://doi.org/10.30089/JAF.202112_68(4).0003

摘要

The oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), is a polyphagous tephritid that causes both economic losses and quarantine risks to many important fruit crops in Taiwan. We evaluated the effects of constant temperatures on the survival rates and reproduction of a generalist fruit fly pupal parasitoid, Dirhinus giffardii Silvestri (Hymenoptera: Chalcididae). The goal was to establish baseline data for its optimal rearing conditions on oriental fruit fly. The results show that D. giffardii survives at a wide range of temperatures from 10 to 35°C. At 25 and 30°C, the highest number of progeny was recorded on days 13 and 20 after emergence with 3.5 ± 0.3 and 4.9 ± 0.3 offspring per female, respectively. The mean total numbers of progeny produced per female of D. giffardii were 16.3 ± 1.6, 77.0 ± 0.3, and 88.3 ± 1.3 progeny at 20, 25, and 30°C, respectively. A significantly higher female-to-male ratio of 0.7 was also found at 25 and 30°C. The age of the host pupae did not significantly affect the parasitism rate among 1 to 5-day-old pupae. The findings of this study reveal a specific temperature that could improve rearing conditions for D. giffardii.

關鍵字

Bactrocera dorsalis ； Dirhinus giffardii ； parasitoid ； reproduction