Exploration for native parasitoids of Drosophila suzukii in China reveals a diversity of parasitoid species and narrow host range of the dominant parasitoid

Authors: GIORGINI, MASSIMO - National Research Council - Italy; WANG, XIN-GENG - University Of California; WANG, YAN - Academy Of Agricultural Science; CHEN, FUSHOU - Academy Of Agricultural Science; ZHANG, HONG-MEI - Academy Of Agricultural Science; CHEN, ZONG-QI - Academy Of Agricultural Science; CASCONE, PASQUALE - National Research Council - Italy; FORMISANO, GIROGIO - National Research Council - Italy; CARVALHO, GISLAINE - Universidade Federal De Vicosa; Buffington, Matthew; Hoelmer, Kim; GUERRIERI, EMILIO - National Research Council - Italy

Submitted to: Journal of Pest Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/3/2018
Publication Date: 12/12/2018
Citation: Giorgini, M., Wang, X., Wang, Y., Chen, F., Zhang, H., Chen, Z., Cascone, P., Formisano, G., Carvalho, G.A., Buffington, M.L., Hoelmer, K.A., Guerrieri, E. 2018. Exploration for native parasitoids of Drosophila suzukii in China reveals a diversity of parasitoid species and narrow host range of the dominant parasitoid. Journal of Pest Science. 92:509-522. https://doi.org/10.1007/s10340-018-01068-3.
DOI: https://doi.org/10.1007/s10340-018-01068-3

Interpretive Summary: The pestiferous spotted wing drosophila fly costs the soft fruit industry of the United States some $550mil/year in lost revenue. These flies eat fruit from the inside out, rendering useless products and disturbed consumers. Parasitoid wasps are natrual enemies of these flies, killing them before destruction of the fruit begins. Even better, pesticides are not needed. This paper summarizes surveys conducted in the native habitat of SWD (China) and reports on what parasitoid species were recovered in numbers sufficient enough for effective biological control. The biological control community, APHIS, and extensiuon entomologists will use these data for management decisions.

Technical Abstract: The invasive spotted wing drosophila, Drosophila suzukii Matsumura (Dipt.: Drosophilidae), a native of East Asia, has widely established in North America and Europe, where it is a serious pest of berry and small fruit crops. The lack of effective indigenous parasitoids of D. suzukii in the recently colonized regions prompted the surveys for co-evolved parasitoids in China during 2013 to 2016. From banana-baited fruit traps (2013-2015) 458 adult parasitoids of drosophilids were reared, comprised mostly of Braconidae (49.56%), Figitidae (37.55%), Diapriidae (7.42%), and Pteromalidae (5.46%). The seven braconid species collected were all Asobara species, primarily Asobara mesocauda van Achterberg and Guerrieri (36.46%), the figitids were primarily Leptopilina japonica japonica Novkovic & Kimura, and the diapriid and pteromalid were the pupal parasitoids Trichopria drosophilae Perkins and Pachycrepoideus vindemiae (Rondani), respectively. Collections from wild fruits in 2016 provided more interesting results with 14,183 drosophilids reared, mostly comprised of D. suzukii or D. pulchrella. Larval parasitoids reared were predominantly Ganaspis brasiliensis (Ihering) and L. j. japonica, with percentage parasitism of drosophilids from berries of Rubus foliosus (22.35%), Rubus niveus (18.81%), Fragaria moupinensis (19.75%), and Sambucus adnata (63.46%). Comparison of banana baited traps and field collected fruit suggests that G. brasiliensis is a specialist on D. suzukii-like flies, and molecular analysis showed two G. brasiliensis lineages that are discussed with previous collections in Japan. Among the parasitoid species identified in D. suzukii’s native range, G. brasiliensis from Yunnan has been the most specialized and effective.