Postgraduate Program in Plant Biology, Institute of Biology, University of Campinas - UNICAMP, Campinas, SP, Brazil.
Laboratory of Chemical Ecology, Department of Animal Biology, Institute of Biology, University of Campinas - UNICAMP, 13083-862, Campinas, SP, Brazil.
Sci Rep. 2019 Oct 23;9(1):15206. doi: 10.1038/s41598-019-51528-8.
In order to evaluate the geographic mosaic theory of coevolution, it is crucial to investigate geographical variation on the outcome of ecological interactions and the functional traits which dictate these outcomes. Plant populations are attacked by specialist and non-specialist herbivores and may have different types of chemical and biotic defences. We investigated geographical and seasonal variation in the interaction between the plant Crotalaria pallida and its two major herbivores (the specialist Utetheisa ornatrix and the non-specialist Etiella zinckenella). We first showed that attack by the two herbivores and a chemical and a biotic defence vary greatly in time and space. Second, we performed a common garden experiment that revealed genetic variation among populations in herbivore resistance and a chemical defence, but no genetic variation in a biotic defence. Third, we sampled 20 populations on a much larger geographical scale and showed great variation in attack rates by the two herbivores and a chemical defence. Finally, we showed that herbivory is not correlated with a chemical defence in the 20 field populations. Our study shows that to understand the evolution of ecological interactions it is crucial to investigate how the outcome of the interaction and the important species traits vary geographically and seasonally.
为了评估协同进化的地理镶嵌理论，研究生态相互作用的结果以及决定这些结果的功能特征的地理变异至关重要。植物种群受到专性和非专性食草动物的攻击，并且可能具有不同类型的化学和生物防御。我们研究了植物 Crotalaria pallida 与其两种主要食草动物（专性 Utetheisa ornatrix 和非专性 Etiella zinckenella）之间相互作用的地理和季节变化。我们首先表明，两种食草动物的攻击以及一种化学和一种生物防御在时间和空间上都有很大的变化。其次，我们进行了一个共同的园林实验，结果表明，在食草动物抗性和一种化学防御方面，种群之间存在遗传变异，但在一种生物防御方面没有遗传变异。第三，我们在更大的地理尺度上对 20 个种群进行了采样，结果表明，两种食草动物和一种化学防御的攻击率存在很大差异。最后，我们表明，在 20 个野外种群中，食草动物的取食与化学防御没有相关性。我们的研究表明，为了理解生态相互作用的进化，研究相互作用的结果以及重要的物种特征如何在地理和季节上变化至关重要。
