Dissertation Research: Resistance to Herbicide and Susceptibility to Herbivores: Testing the Mechanistic Basis of a Trade-off and its Population-level Consequences

研究人员将测试草食性昆虫影响苋菜（Amaranthus hybridus）对除草剂三嗪抗性成本的机制。抗三嗪突变通过减缓光合作用而付出代价。突变植物更容易被食草动物吃掉，对摄食伤害的耐受性较差，暴露在食草动物面前时适应性成本增加。这项工作将解决光和营养的可用性如何影响突变植物对碳基防御的分配及其对食草动物的易感性。食草动物施加频率依赖选择的可能性将被测试。此外，研究人员将测试突变植物是否增加了对碳获取（即叶片）的分配，而牺牲了营养和水分获取（即根），从而导致其耐受性降低。这项研究将为光合速率如何形成防御和耐受性模式提供一个独立的测试，并将有助于未来管理除草剂抗性的策略。研究人员将测试食草昆虫影响藜草（苋科）对除草剂三嗪抗性成本的机制。抗三嗪突变通过减缓光合作用而付出代价。突变植物更容易被食草动物吃掉，对摄食伤害的耐受性较差，暴露在食草动物面前时适应性成本增加。这项工作将解决光和营养的可用性如何影响突变植物对碳基防御的分配及其对食草动物的易感性。食草动物施加频率依赖选择的可能性将被测试。此外，研究人员将测试突变植物是否增加了对碳获取（即叶片）的分配，而牺牲了营养和水分获取（即根），从而导致其耐受性降低。这项研究将为光合速率如何形成防御和耐受性模式提供一个独立的测试，并将有助于未来管理除草剂抗性的策略。

AbstractFutuyma 0206448The researchers will test the mechanisms by which herbivorous insects affect the cost of resistance to the herbicide triazine in pigweed Amaranthus hybridus (Amaranthaceae). The triazine-resistance mutation imposes a cost by slowing photosynthesis. Mutant plants are preferentially eaten by herbivores, are less tolerant of feeding damage, and suffer an increased fitness cost when exposed to herbivores. This work will address how the availability of light and nutrients affects a mutant plant's allocation to carbon-based defenses and its susceptibility to herbivores. The potential for herbivores to impose frequency-dependent selection will be tested. Additionally, the researchers will test if a mutant plant's increased allocation to carbon acquisition (i.e. leaves) at the expense of nutrient and water acquisition (i.e. roots) causes its reduced tolerance. This research will provide an independent test of how photosynthetic rate shapes patterns of defense and tolerance, and it will contribute to future strategies for managing resistance to herbicide.The researchers will test the mechanisms by which herbivorous insects affect the cost of resistance to the herbicide triazine in pigweed Amaranthus hybridus (Amaranthaceae). The triazine-resistance mutation imposes a cost by slowing photosynthesis. Mutant plants are preferentially eaten by herbivores, are less tolerant of feeding damage, and suffer an increased fitness cost when exposed to herbivores. This work will address how the availability of light and nutrients affects a mutant plant's allocation to carbon-based defenses and its susceptibility to herbivores. The potential for herbivores to impose frequency-dependent selection will be tested. Additionally, the researchers will test if a mutant plant's increased allocation to carbon acquisition (i.e. leaves) at the expense of nutrient and water acquisition (i.e. roots) causes its reduced tolerance. This research will provide an independent test of how photosynthetic rate shapes patterns of defense and tolerance, and it will contribute to future strategies for managing resistance to herbicide.