傳粉者和植食者是否會造成花部化學特徵選汰上的衝突？

文獻來源：A Kessler & R Halitschke. 2009. Testing the potential for conflicting selection on floral chemical traits by pollinators and herbivores: predictions and case study. Functional Ecology 23: 901–912. doi: 10.1111/j.1365-2435.2009.01639.x

摘要
1.透過寄主植物在演化和行為上的反應，傳粉者和植食者能有許多種交互作用的方式。
2.由於傳粉者和植食者皆消費植物並依賴植物產生的營養和次級代謝物、以及利用植物訊息，植物化學應該是他們之間最主要的交互作用媒介。
3.作者建立了傳粉者和植食者之間以植物為媒介者的概念架構。作者著重在植物化學、尤其是植物揮發物，目標則在於統整植物防禦和傳粉的假說。作者提出對雙方演化結局的預測-傳粉者和植食者衝突的演化壓力起因於受植物化學之限制。
4.作者進一步提出植物為避免在“吸引傳粉者”與“抵禦植食者”之間產生衝突，能夠透過在特定組織調節對傳粉者的化學回饋、和由植食者引發的花部化學和形態之假說。
5.最後，作者利用野生種馬鈴薯(Solanum peruvianum)測試他們所預測的各個觀點，以闡述植物化學中“組織專一性”和“植食者誘導”之差異的多樣性，可能影響傳粉者與植食者之行為和植物的適應度。

SUMMARY
1. There are myriad ways in which pollinators and herbivores can interact via the evolutionary and behavioural responses of their host plants.
2. Given that both herbivores and pollinators consume and are dependent upon plant-derived nutrients and secondary metabolites, and utilize plant signals, plant chemistry should be one of the major factors mediating these interactions.
3. Here we build upon a conceptual framework for understanding plant-mediated interactions of pollinators and herbivores. We focus on plant chemistry, in particular plant volatiles and aim to unify hypotheses for plant defence and pollination. We make predictions for the evolutionary outcomes of these interactions by hypothesizing that conflicting selection pressures from herbivores and pollinators arise from the constraints imposed by plant chemistry.
4. We further hypothesize that plants could avoid conflicts between pollinator attraction and herbivore defence through tissue-specific regulation of pollinator reward chemistry, as well as herbivore-induced changes in flower chemistry and morphology.
5. Finally, we test aspects of our predictions in a case study using a wild tomato species, Solanum peruvianum, to illustrate the diversity of tissue-specific and herbivore-induced differences in plant chemistry that could influence herbivore and pollinator behaviour, and plant fitness.

Key-words: plant–insect interactions, coevolution, plant defences, induced responses to herbivory, pollinator limitation