Garcia Alejandro, Martinez Manuel, Diaz Isabel, Santamaria M Estrella
Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid - Instituto Nacional de Investigación y Tecnología Agraria y Alimentación, Madrid, Spain.
Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, Madrid, Spain.
Front Plant Sci. 2021 Jan 21;11:615122. doi: 10.3389/fpls.2020.615122. eCollection 2020.
Plants and phytophagous arthropods have co-evolved for millions of years. During this long coexistence, plants have developed defense mechanisms including constitutive and inducible defenses. In an effort to survive upon herbivore attack, plants suffer a resource reallocation to facilitate the prioritization of defense toward growth. These rearrangements usually end up with a penalty in plant growth, development or reproduction directly linked to crop losses. Achieving the balance to maximize crop yield requires a fine tune regulation specific for each host-arthropod combination, which remains to be fully elucidated. The purpose of this work is to evaluate the effects of induced plant defenses produced upon pest feeding on plant fitness and surrogate parameters. The majority of the studies are focused on specific plant-pest interactions based on artificial herbivory damage or simulated defoliation on specific plant hosts. In this meta-analysis, the relevance of the variables mediating plant-pest interactions has been studied. The importance of plant and pest species, the infestation conditions (plant age, length/magnitude of infestation) and the parameters measured to estimate fitness (carbohydrate content, growth, photosynthesis and reproduction) in the final cost have been analyzed through a meta-analysis of 209 effects sizes from 46 different studies. Herbivore infestation reduced growth, photosynthesis and reproduction but not carbohydrate content. When focusing on the analyses of the variables modulating plant-pest interactions, new conclusions arise. Differences on the effect on plant growth and photosynthesis were observed among different feeding guilds or plant hosts, suggesting that these variables are key players in the final effects. Regarding the ontogenetic stage of a plant, negative effects were reported only in infestations during the vegetative stage of the plant, while no effect was observed during the reproductive stage. In addition, a direct relation was found between the durability and magnitude of the infestation, and the final negative effect on plant fitness. Among the parameters used to estimate the cost, growth and photosynthesis revealed more differences among subgroups than reproduction parameters. Altogether, this information on defense-growth trade-offs should be of great help for the scientific community to design pest management strategies reducing costs.
植物和植食性节肢动物已经共同进化了数百万年。在这种长期共存的过程中，植物形成了包括组成型防御和诱导型防御在内的防御机制。为了在遭受食草动物攻击后生存下来，植物会进行资源重新分配，以便将防御置于比生长更优先的地位。这些重新安排通常最终会导致植物生长、发育或繁殖受到损害，而这直接与作物损失相关。要实现平衡以最大化作物产量，需要针对每种寄主 - 节肢动物组合进行精细的调控，而这仍有待充分阐明。这项工作的目的是评估害虫取食后诱导产生的植物防御对植物适合度及替代参数的影响。大多数研究集中在基于人工食草损伤或特定植物寄主上模拟落叶的特定植物 - 害虫相互作用。在这项荟萃分析中，研究了介导植物 - 害虫相互作用的变量的相关性。通过对来自46项不同研究的209个效应量进行荟萃分析，分析了植物和害虫种类、侵染条件（植物年龄、侵染的长度/程度）以及在最终代价中用于估计适合度的参数（碳水化合物含量、生长、光合作用和繁殖）的重要性。食草动物侵染会降低生长、光合作用和繁殖，但不会降低碳水化合物含量。当专注于对调节植物 - 害虫相互作用的变量进行分析时，会得出新的结论。在不同的取食类群或植物寄主之间，观察到对植物生长和光合作用的影响存在差异，这表明这些变量是最终影响的关键因素。关于植物的个体发育阶段，仅在植物营养阶段的侵染中报告了负面影响，而在生殖阶段未观察到影响。此外，发现侵染的持续时间和程度与对植物适合度的最终负面影响之间存在直接关系。在用于估计代价的参数中，生长和光合作用在亚组之间显示出比繁殖参数更多的差异。总之，这些关于防御 - 生长权衡的信息应该对科学界设计降低成本的害虫管理策略有很大帮助。
