Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA.
Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA.
Trends Ecol Evol. 2016 Aug;31(8):646-656. doi: 10.1016/j.tree.2016.05.007. Epub 2016 Jun 7.
One of the most well-supported theories regarding the evolution of plant defenses is the resource availability hypothesis (RAH). RAH posits that species from high-resource environments grow fast and allocate little to herbivore-resistance traits, whereas those species in low-resource environments grow slow and are highly resistant to herbivores. However, within species, how resources influence defense is unclear and existing theories make opposing predictions. Here, we review studies documenting intraspecific variation in plant defense across resource gradients and find little support for RAH. We outline why RAH does not apply intraspecifically and present a predictive framework for understanding how resources influence intraspecific variation in plant defense. Our framework provides an important step towards reconciling inter- versus intraspecific strategies of defense.
关于植物防御进化最有依据的理论之一是资源可用性假说（RAH）。RAH 假定，来自高资源环境的物种生长迅速，对食草动物抗性特征的分配很少，而那些来自低资源环境的物种生长缓慢，对食草动物具有高度抗性。然而，在物种内部，资源如何影响防御尚不清楚，并且现有的理论做出了相反的预测。在这里，我们回顾了记录植物防御在资源梯度上的种内变异的研究，发现对 RAH 的支持很少。我们概述了为什么 RAH 在种内不适用，并提出了一个预测框架，以了解资源如何影响植物防御的种内变异。我们的框架为理解资源如何影响植物防御的种内变异提供了一个重要步骤，从而有助于协调防御的种间和种内策略。
