由于逃逸了原產(chǎn)地具協(xié)同進(jìn)化歷史,、專一性天敵的調(diào)控,，外來植物改變資源分配策略，將部分原本用于防御的資源用于生長,，取得相對(duì)于本地植物較強(qiáng)的競爭優(yōu)勢,，是外來植物成功入侵的重要機(jī)制。但是,，伴隨入侵時(shí)間推移,，一些本地天敵將在入侵植物上聚集，建立新的植物-天敵互作關(guān)系,；同時(shí),，人們會(huì)有意或無意引入外來植物專一性天敵，重新構(gòu)建植物-天敵互作關(guān)系,，因而外來植物逃逸天敵調(diào)控只是暫時(shí)的,。
逃逸天敵調(diào)控對(duì)外來植物防御策略（包括抗性和耐受性）的影響一直備受關(guān)注，而入侵地新建立或重新構(gòu)建的植物-天敵互作如何影響外來植物防御策略（尤其是耐受性）,，目前研究較少,。
中科院武漢植物園入侵植物生物學(xué)課題組以入侵植物空心蓮子草為對(duì)象開展了相關(guān)研究，相關(guān)研究結(jié)果發(fā)表于Biological Invasions 雜志,。
空心蓮子草于上世紀(jì)30年代被引入我國,，目前在我國長江中下游地區(qū)危害特別嚴(yán)重。為控制空心蓮子草,，我國于1986年引入其天敵昆蟲蓮草直胸跳甲,。同時(shí)，本地天敵昆蟲蝦鉗菜披龜甲也對(duì)空心蓮子草造成危害,。然而在空心蓮子草發(fā)生地域,，兩種天敵昆蟲均呈斑塊狀分布，即兩種天敵只發(fā)生于部分地區(qū),。
通過比較研究有無天敵昆蟲取食歷史的空心蓮子草種群耐受性水平,，研究人員發(fā)現(xiàn)：有取食歷史空心蓮子草種群將更多資源分配到地下組織，顯著提高植株對(duì)昆蟲脅迫的耐受能力,，表明取食歷史顯著提高植物耐受天敵昆蟲脅迫的能力,；研究同時(shí)發(fā)現(xiàn)，本地天敵蝦鉗菜披龜甲和生防天敵蓮草直胸跳甲長期取食對(duì)空心蓮子草耐受性的影響無顯著差異,。該項(xiàng)工作對(duì)于指導(dǎo)外來入侵植物生物防治具有重要的理論價(jià)值。（生物谷 bioon.com）
doi:10.1007/s10530-011-0106-8
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History of exposure to herbivores increases the compensatory ability of an invasive plant
Xinmin Lu,，Jianqing Ding
Release from natural enemies is frequently cited as an important factor contributing to plant invasions. But such effects are likely to be temporary—native herbivores can form new plant-herbivore associations and co-evolved insects might reach the new range. While the potential effects of the initial enemy release have been well studied, the consequences of any resumption of herbivory are poorly understood. Alternanthera philoxeroides is one of the most widespread invasive plants in China and is attacked both by a specialist herbivore introduced from the native range, Agasicles hygrophila, and a native beetle Cassida piperata Hope which has formed a new association. However, these insects are not found throughout the invaded range. To test the effect of the history of population exposure to herbivory on compensatory ability, plants were cultured from 14 populations around China that differed in whether A. hygrophila or C. piperata were present. Treatment plants were exposed to herbivory by A. hygrophila for a week until 50% of the leaf area was defoliated, then grown for 80 days. Plants from populations with prior exposure to herbivory (of any kind) accumulated more root mass than populations without prior exposure, indicating that prior exposure to insects can stimulate plant compensation to herbivory. We would recommend that potential changes in plant tolerance in response to prior exposure to herbivory are considered in invasive plant management plans that employ bio-control agents.
