Marquis Robert J
Department of Entomology, University of Illinois, Urbana, IL, 61801.
Evolution. 1990 Feb;44(1):104-120. doi: 10.1111/j.1558-5646.1990.tb04282.x.
The shrub Piper arieianum (Piperaceae) has a diverse herbivore fauna (95 species total) in Costa Rican rain forest. The effect of plant genotype on leaf damage by individual herbivore species and total leaf area removed was studied in P. arieianum through a cloning experiment. Damage patterns were measured over 3.5 years for two plots, four genotypes per plot, in the understory of lowland rain forest. In both plots, there were significant differences among genotypes in total leaf area missing throughout the study period. Rankings of genotypes based on overall damage remained constant over time in plot 1 but changed in plot 2. Certain individual herbivore species caused significantly higher damage in some genotypes than in others; the change in genotype rankings in plot 2 was associated with increased damage to particular genotypes by specific herbivore groups. The genotype most heavily damaged by a given insect species varied depending on the herbivore species; thus, resistance to one herbivore species did not necessarily confer resistance against all species. Those herbivore species causing the greatest proportion of damage for a given plant changed over time. Because total damage resulted from the summation of losses to individual herbivore species, whether an individual plant lost more leaf area than its neighbors depended on the relative abundance of the herbivore species at any one time. Finally, for a portion of the study period in each plot, more heavily damaged clones grew less than lesser damaged clones. Together with previous reports that naturally growing plants differ significantly in damage and that these differences are sufficient to cause fitness differences, the results presented here suggest that the herbivores of P. arieianum represent a selective force for changes in resistance but that this selective force changes both in intensity and quality over time.
灌木阿里埃胡椒（胡椒科）在哥斯达黎加雨林中有着丰富多样的食草动物群落（总计95种）。通过克隆实验，研究了阿里埃胡椒中植物基因型对单个食草动物物种造成的叶片损伤以及去除的总叶面积的影响。在低地雨林林下，对两个样地进行了3.5年的损伤模式测量，每个样地有四种基因型。在两个样地中，整个研究期间缺失的总叶面积在基因型之间均存在显著差异。在样地1中，基于总体损伤的基因型排名随时间保持不变，但在样地2中发生了变化。某些单个食草动物物种对某些基因型造成的损伤明显高于其他基因型；样地2中基因型排名的变化与特定食草动物群体对特定基因型损伤的增加有关。给定昆虫物种造成损伤最严重的基因型因食草动物物种而异；因此，对一种食草动物物种的抗性不一定能赋予对所有物种的抗性。对于给定植物造成最大损伤比例的那些食草动物物种会随时间变化。由于总损伤是各个食草动物物种造成损失的总和，一株植物是否比其邻居损失更多的叶面积取决于任何时候食草动物物种的相对丰度。最后，在每个样地研究期间的一部分时间里，损伤更严重的克隆体生长速度比损伤较轻的克隆体慢。结合之前关于自然生长植物在损伤方面存在显著差异且这些差异足以导致适合度差异的报道，此处呈现的结果表明，阿里埃胡椒的食草动物代表了抗性变化的一种选择力，但这种选择力在强度和性质上都会随时间变化。
