Department of Botany, Faculty of Science, Charles University, Praha, Czech Republic.
PLoS One. 2013 May 22;8(5):e64639. doi: 10.1371/journal.pone.0064639. Print 2013.
Plant traits are the key factors that determine herbivore foraging selection. The traits serving as defense traits against herbivores represent a wide range of traits, such as chemical, physiological, morphological and life-history traits. While many studies considered plant defense traits at the within-species scale, much less is known from comparisons of a wide range of closely related species. The aim of this study was to identify factors responsible for the intensity of leaf damage in the Carduoideae subfamily of Asteraceae, which hosts many invasive species and thus is potential candidate plant species that could be controlled by biological control. Specifically, we wanted to see the relative importance of habitat characteristics, plant size and plants traits in determining the degree of folivory. The study identified several defense traits able to explain differences in herbivory between species after accounting for differences in the habitats in which the species occur and the plant size. Specifically, the most important traits were traits related to the quality of the leaf tissue expressed as the content of phosphorus, water and specific leaf area, which suggests that the leaf quality had a more important effect on the degree of herbivory than the presence of specific defense mechanisms such as spines and hair. Leaf quality is thus a candidate factor that drives herbivore choice when selecting which plant to feed on and should be considered when assessing the danger that a herbivore will switch hosts when introduced to a new range.
植物特性是决定食草动物觅食选择的关键因素。作为抵御食草动物的防御特性的特性代表了广泛的特性，如化学、生理、形态和生活史特性。虽然许多研究都考虑了物种内的植物防御特性，但从广泛相关的密切相关的物种的比较中，我们了解的就少得多了。本研究的目的是确定负责菊科紫菀族叶片损伤强度的因素，该族拥有许多入侵物种，因此是可以通过生物防治控制的潜在候选植物物种。具体来说，我们想看看生境特征、植物大小和植物特性在决定食草程度方面的相对重要性。研究确定了几种防御特性，这些特性在考虑到物种所处的栖息地差异和植物大小后，能够解释物种间食草程度的差异。具体来说，最重要的特性是与叶片组织质量有关的特性，表现为磷、水和比叶面积的含量，这表明叶片质量对食草程度的影响比特定防御机制（如刺和毛发）的存在更为重要。因此，叶片质量是当食草动物选择食用哪种植物时驱动食草动物选择的候选因素，在评估食草动物在引入新范围时是否会转而取食其他植物时，应该考虑这一因素。
