Gardner Allison M, Allan Brian F, Frisbie Lauren A, Muturi Ephantus J
Department of Entomology, University of Illinois at Urbana-Champaign, 505 S. Goodwin Ave., Urbana, IL, 61801, USA.
School of Integrative Biology, University of Illinois at Urbana-Champaign, 505 S. Goodwin Ave., Urbana, IL, 61801, USA.
Parasit Vectors. 2015 Jun 16;8:329. doi: 10.1186/s13071-015-0941-z.
Exotic invasive plants alter the structure and function of native ecosystems and may influence the distribution and abundance of arthropod disease vectors by modifying habitat quality. This study investigated how invasive plants alter the ecology of Culex pipiens, an important vector of West Nile virus (WNV) in northeastern and midwestern regions of the United States.
Field and laboratory experiments were conducted to test the hypothesis that three native leaf species (Rubus allegheniensis, blackberry; Sambucus canadensis, elderberry; and Amelanchier laevis, serviceberry), and three exotic invasive leaf species (Lonicera maackii, Amur honeysuckle; Elaeagnus umbellata, autumn olive; and Rosa multiflora, multiflora rose) alter Cx. pipiens oviposition site selection, emergence rates, development time, and adult body size. The relative abundance of seven bacterial phyla in infusions of the six leaf species also was determined using quantitative real-time polymerase chain reaction to test the hypothesis that variation in emergence, development, and oviposition site selection is correlated to differences in the diversity and abundance of bacteria associated with different leaf species, important determinants of nutrient quality and availability for mosquito larvae.
Leaf detritus from invasive honeysuckle and autumn olive yielded significantly higher adult emergence rates compared to detritus from the remaining leaf species and honeysuckle alleviated the negative effects of intraspecific competition on adult emergence. Conversely, leaves of native blackberry acted as an ecological trap, generating high oviposition but low emergence rates. Variation in bacterial flora associated with different leaf species may explain this asymmetrical production of mosquitoes: emergence rates and oviposition rates were positively correlated to bacterial abundance and diversity, respectively.
We conclude that the displacement of native understory plant species by certain invasive shrubs may increase production of Cx. pipiens with potential negative repercussions for human and wildlife health. These findings may be relevant to mosquito control and invasive plant management practices in the geographic range of Cx. pipiens. Further, our discovery of a previously unknown ecological trap for an important vector of WNV has the potential to lead to novel alternatives to conventional insecticides in mosquito control by exploiting the apparent "attract-kill" properties of this native plant species.
外来入侵植物会改变本地生态系统的结构和功能，并可能通过改变栖息地质量来影响节肢动物疾病媒介的分布和数量。本研究调查了入侵植物如何改变美国东北部和中西部地区西尼罗河病毒（WNV）的重要传播媒介——致倦库蚊的生态。
进行了野外和实验室实验，以检验以下假设：三种本地叶物种（阿勒格尼悬钩子，黑莓；加拿大接骨木，接骨木；光滑唐棣，唐棣）和三种外来入侵叶物种（金银忍冬，金银木；翅果油树，秋橄榄；多花蔷薇，多花蔷薇）会改变致倦库蚊的产卵地点选择、羽化率、发育时间和成虫体型。还使用定量实时聚合酶链反应测定了六种叶物种浸出液中七个细菌门的相对丰度，以检验以下假设：羽化、发育和产卵地点选择的差异与不同叶物种相关细菌的多样性和丰度差异相关，而这些细菌是蚊子幼虫营养质量和可利用性的重要决定因素。
与其他叶物种的碎屑相比，入侵性金银木和秋橄榄的落叶碎屑产生的成虫羽化率显著更高，并且金银木减轻了种内竞争对成虫羽化的负面影响。相反，本地黑莓叶充当了生态陷阱，产卵率高但羽化率低。与不同叶物种相关的细菌菌群差异可能解释了蚊子这种不对称的产出情况：羽化率和产卵率分别与细菌丰度和多样性呈正相关。
我们得出结论，某些入侵灌木取代本地林下植物物种可能会增加致倦库蚊的数量，对人类和野生动物健康产生潜在负面影响。这些发现可能与致倦库蚊地理范围内的蚊虫控制和入侵植物管理实践相关。此外，我们发现了一种以前未知的西尼罗河病毒重要传播媒介的生态陷阱，这有可能通过利用这种本地植物物种明显的“吸引-杀灭”特性，为蚊虫控制中传统杀虫剂带来新的替代品。
