|Galina, Yurchenko - Ministry Of Agriculture Of The Russian Federation|
|Juli, Gould - Animal And Plant Health Inspection Service (APHIS)|
|Wang, Xiao-yi - Chinese Academy Of Forestry|
|Yang, Zhong-qi - Chinese Academy Of Forestry|
|Bauer, Leah - Us Forest Service (FS)|
|Abell, Kristopher - University Of Massachusetts|
|Driesche, Roy Van - University Of Massachusetts|
Submitted to: USDA Interagency Research Forum on Invasive Species
Publication Type: Proceedings
Publication Acceptance Date: 3/30/2011
Publication Date: 1/13/2015
Citation: Duan, J.J., Galina, Y., Juli, G., Wang, X., Yang, Z., Bauer, L., Abell, K.J., Driesche, R. 2015. The impact of biotic factors on populations of the emerald ash borer: a comparison between its native northeast asian and newly invaded north american ranges. USDA Interagency Research Forum on Invasive Species. p. 14; p. 24; p. 70..
Technical Abstract: Between its discovery in Michigan and Ontario in 2002 and 2010, the emerald ash borer (EAB), Agrilus planipennis (Coleoptera: Buprestidae), spread to 15 US states and two provinces in Canada. Understanding population dynamics in both the pest’s native range of northeast Asia and the newly invaded region in North America is critically important to development of effective manage strategies for suppression of emerald ash borer. It is known that populations of EAB are affected by a variety of biotic factors in part of its native range such as northeast China and the Russian Far East (Liu et al. 2003, 2007; Yang et al. 2010), as well as in some newly invaded areas in North America (Cappaert and McCullough 2009, Kula et al. 2010, Duan et al. 2009, Duan et al. 2010a,b). These factors include host tree defense, woodpecker predation, disease, and both endemic and introduced hymenopteran parasitoids. To date, however, there have been no systematic studies on the comparative impact of these different biotic factors on population dynamics of EAB in northeast Asia and North America. To compare the impact of different biotic factors on population dynamics of EAB, we sampled larval stages of EAB populations and measured mortality from parasitoids, predators, host plant resistance, and microbial diseases in both northeast Asia (Russian Far East and northeast China) and North America (Michigan). Results from our studies in northeast Asia showed that two braconid parasitoids (Spathius sp. and Antanycolus picipes Telenga) were the dominant mortality factors of larval EAB infesting planted North American ash (Fraxinus pennsylvanica), causing 65% larval mortality. In EAB populations infesting Oriental species of ash (F. ryhchophylla or F. manschurica), however, the dominant mortality factor was host-plant resistance, which killed >75% of feeding EAB larvae by forming callus around young larvae and/or the dieback of cambium tissues surrounding EAB larvae. Predation by woodpeckers and microbial diseases caused less than 5% mortality to larvae. In contrast, the results of three years of field studies in North America (Michigan) showed that several species of North American woodpeckers and one group of North American braconid parasitoids (primarily Antanycolus cappaerti) have become the primary biotic factors killing EAB larvae. Mortality of EAB larvae from parasitism and predation in Michigan increased nearly five-fold from 2009 to 2010, suggesting that the role of natural enemies in North American EAB populations is changing rapidly.