Haavik Laurel J, Allison Jeremy D, MacQuarrie Chris J K, Nott Reginald W, Ryan Kathleen, de Groot Peter, Turgeon Jean J
Natural Resources Canada Canadian Forest Service, Great Lakes Forestry Centre, 1219 Queen St. E, Sault Ste. Marie, ON, P6A 2E5, Canada (
Faculty of Forestry, University of Toronto, 33 Willcocks St., Toronto, ON, M5S 3B3, Canada (
Environ Entomol. 2016 Apr;45(2):320-7. doi: 10.1093/ee/nvv223. Epub 2016 Jan 8.
A nonnative woodwasp, Sirex noctilio F., has established in pine forests in eastern North America. To facilitate prediction of the full range of impacts S. noctilio could have as it continues to spread in North American forest ecosystems, we studied the effects of infection by a nonsterilizing parasitic nematode on S. noctilio size, fecundity, and flight capacity and on the native woodwasp, S. nigricornis, size and fecundity. We also developed predictive models relating size to fecundity for both species. On average, S. noctilio (3.18 ± 0.05 mm) were larger than S. nigricornis (2.19 ± 0.04 mm). For wasps of similar size, S. nigricornis was more fecund. Nematode infection negatively affected potential fecundity by a mean difference of 36 and 49 eggs in S. noctilio and S. nigricornis, respectively. Nematode-infected males of S. noctilio, however, were larger than uninfected individuals. Nematode infection showed inconsistent results on mean speed and total distance flown by S. noctilio males and females. Nematode infection did not affect total distance flown by females, and so is unlikley to have a direct, or strong influence on S. noctilio flight capacity. Models developed to predict fecundity of Sirex spp. from body size, based on the close relationship between pronotum width and potential fecundity for both species (R(2) ≥ 0.69), had low measures of error when compared with true values of fecundity (± 25-26 eggs).
一种非本地木蜂，即夜蛾木蜂（Sirex noctilio F.），已在北美东部的松林中定殖。为便于预测夜蛾木蜂在北美森林生态系统中持续扩散可能产生的全面影响，我们研究了一种非绝育寄生线虫感染对夜蛾木蜂的大小、繁殖力和飞行能力以及对本地木蜂黑角木蜂（S. nigricornis）的大小和繁殖力的影响。我们还针对这两个物种开发了将大小与繁殖力相关联的预测模型。平均而言，夜蛾木蜂（3.18 ± 0.05毫米）比黑角木蜂（2.19 ± 0.04毫米）更大。对于大小相似的木蜂，黑角木蜂的繁殖力更强。线虫感染分别使夜蛾木蜂和黑角木蜂的潜在繁殖力平均减少36枚和49枚卵。然而，受线虫感染的夜蛾木蜂雄性比未感染个体更大。线虫感染对夜蛾木蜂雄性和雌性的平均飞行速度和飞行总距离的影响结果不一致。线虫感染并未影响雌性的飞行总距离，因此不太可能对夜蛾木蜂的飞行能力产生直接或强烈影响。基于两个物种前胸宽度与潜在繁殖力之间的密切关系（R²≥0.69），开发的用于根据体型预测木蜂属繁殖力的模型，与繁殖力真实值相比误差较小（±25 - 26枚卵）。
