Demographic models inform selection of biocontrol agents for garlic mustard (Alliaria petiolata).
Demographic models inform selection of biocontrol agents for garlic mustard (Alliaria petiolata).
复制标题
人口统计模型为蒜芥（Alliaria petiolata）生物防治剂的选择提供了信息。
作者：
A. Davis;D. Landis;V. Nuzzo;B. Blossey;E. Gerber;H. Hinz
外来入侵植物对全球自然群落构成了重大威胁。通过有选择地引入其天敌对杂草进行生物控制可以影响大面积的控制，但也有可能产生非目标效应。为了最大限度地提高有效性，同时降低风险，杂草生物防治计划应该引入最少数量的寄主特异性天敌，以控制入侵的非本地植物。我们使用矩阵模型的弹性分析来帮助指导大蒜芥菜（Alliaria petiolata (M. Bieb)）的生物防治剂选择。卡瓦拉和格兰德)。欧亚二年生植物A. petiolata被认为是北美温带森林中最具问题的入侵者之一。目前有4种象鼻虫（鞘翅目：象鼻虫科）被认为是潜在的生物防治剂。这些物种攻击小叶蝉的莲座（C. scrobicollis）、茎（C. roberti， C. alliariae）和种子（C. constrictus）。利用北美小叶茅种群参数进行的弹性分析表明，花丛到花丛的转变和繁殖力的变化对种群增长率的影响最大。这些结果表明，以玫瑰为食的scrobicollis的攻击会减少越冬存活率，而以种子或茎为食的攻击会减少种子产量，这应该是特别有效的。模型结果差异很大，因为在北美观测到的范围内，小叶青虫种群参数变化很大，这表明成功控制小叶青虫种群可能发生在某些条件下，但不是所有条件下。通过这些先验分析，我们预测：(1)莲座死亡率和种子产量减少将是影响小叶青树种群数量的最重要因素；(2)根冠取食方式对小叶青种群数量的影响最为显著；(3)单一药剂的释放不太可能控制小叶青虫的整个人口变异范围；(4)需要同时降低莲座成活率和种子产量的药剂组合来抑制最旺盛的小叶茅种群。这些预测可以通过建立的长期监测点和设计的释放程序进行测试。如果人口统计学模型能够成功地预测生物防治剂对入侵植物种群的影响，那么经验和理论方法之间的持续对话和合作可能是未来开发成功的植物入侵生物防治策略的关键。
Nonindigenous invasive plants pose a major threat to natural communities worldwide. Biological control of weeds via selected introduction of their natural enemies can affect control over large spatial areas but also risk nontarget effects. To maximize effectiveness while minimizing risk, weed biocontrol programs should introduce the minimum number of host-specific natural enemies necessary to control an invasive nonindigenous plant. We used elasticity analysis of a matrix model to help inform biocontrol agent selection for garlic mustard (Alliaria petiolata (M. Bieb.) Cavara and Grande). The Eurasian biennial A. petiolata is considered one of the most problematic invaders of temperate forests in North America. Four weevil species in the genus Ceutorhynchus (Coleoptera: Curculionidae) are currently considered potential biocontrol agents. These species attack rosettes (C. scrobicollis), stems (C. roberti, C. alliariae), and seeds (C. constrictus) of A. petiolata. Elasticity analyses using A. petiolata demographic parameters from North America indicated that changes in the rosette-to-flowering-plant transition and changes in fecundity consistently had the greatest impact on population growth rate. These results suggest that attack by the rosette-feeder C. scrobicollis, which reduces overwintering survival, and seed or stem feeders that reduce seed output should be particularly effective. Model outcomes differed greatly as A. petiolata demographic parameters were varied within ranges observed in North America, indicating that successful control of A. petiolata populations may occur under some, but not all, conditions. Using these a priori analyses we predict: (1) rosette mortality and reduction of seed output will be the most important factors determining A. petiolata demography; (2) the root-crown feeder C. scrobicollis will have the most significant impact on A. petiolata demography; (3) releases of single control agents are unlikely to control A. petiolata across its full range of demographic variability; (4) combinations of agents that simultaneously reduce rosette survival and seed production will be required to suppress the most vigorous A. petiolata populations. These predictions can be tested using established long-term monitoring sites coupled with a designed release program. If demographic models can successfully predict biocontrol agent impact on invasive plant populations, a continued dialogue and collaboration between empirical and theoretical approaches may be the key to the development of successful biocontrol tactics for plant invaders in the future.