|SHUAI, HUA - Chinese Academy Of Forestry|
|XIAO-YI, WANG - Chinese Academy Of Forestry|
|ZHONG-QI, YANG - Chinese Academy Of Forestry|
Submitted to: Biological Control
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/3/2019
Publication Date: 3/4/2019
Citation: Shuai, H., Xiao-Yi, W., Zhong-Qi, Y., Duan, J.J. 2019. Effects of photoperiod and light intensity on wing dimorphism and development in the parasitoid Sclerodermus pupariae (Hymenoptera:Bethylidae). Biological Control. 133: 117–122. https://doi.org/10.1016/j.biocontrol.2019.03.003.
Interpretive Summary: Photoperiod is known to affect many aspects of insect life history and can regulate the production of winged vs wingless offspring in some insects, yet little is known about the combined effect of light intensity and day length. Scientists from the Chinese Academy of Forestry and ARS examined how the combined effect of photoperiod and light intensity affected the production of winged offspring of an Asian parasitic wasp that attacks emerald ash borer (an invasive species in the United States). The study showed that more winged offspring were produced with high levels of light intensity and long daylight hours, but their development time was shorter under short-day conditions. These findings may help enhance production of this parasitic wasp for biological control of emerald ash borer.
Technical Abstract: Sclerodermus pupariae Yang and Yao (Hymenoptera: Bethylidae) is a newly described ectoparasitoid which is used as a biocontrol agent against several buprestid and cerambycid larvae in China. Our study evaluated the integrative effects of photoperiodic exposure and light intensity on life-history parameters such as developmental duration, proportion of winged females, fecundity, and offspring sex ratio. Results of the study showed that the percentage of winged female parasitoid progeny under a long photoperiod (L:D = 16:8h) was significantly higher than that under a short photoperiod (L:D = 8:16h and darkness (L:D = 0:24h). Moreover, high intensity light was conducive to the induction of winged individuals in the wasp progeny compared with low intensity light. In addition, the developmental time of parasitoid progeny differed significantly under various light periods. Development time of parasitoids under short-day conditions (L:D = 8:16h) was approximately 2 days less than under long-day conditions and darkness. The proportion of winged females and development rate were significantly influenced by both light intensity and photoperiod. However, the fecundity and sex ratio of this parasitoid were not significantly different among treatments. These findings indicate that the efficiency of mass-rearing S. pupariae may be improved by using a long-day photoperiod and high intensity light.