Keeler Margaret S, Chew Frances S
Department of Biology, Tufts University, Medford, MA 02155, USA.
Oecologia. 2008 Jun;156(3):559-68. doi: 10.1007/s00442-008-1005-2. Epub 2008 Mar 8.
Exotic plants may act as population sinks or evolutionary traps for native herbivores. The native butterfly Pieris oleracea lays eggs on garlic mustard, Alliaria petiolata, but larvae develop very poorly on this exotic invasive plant. We examined oviposition preference of individual females and larval performance of their offspring for individuals from one area where garlic mustard is well established and one where it is absent. These data were used to assess whether garlic mustard is being incorporated into or excluded from the diet. Females from the area without garlic mustard showed a wide range of preference, families had low larval survival on garlic mustard, and larval survivorship showed no correlation with mothers' preferences. Females from the area with garlic mustard preferred it to the native host, and larval survivorship on garlic mustard was positively correlated with the mother's preference. Individuals surviving on garlic mustard took longer to pupate and weighed >30% less compared to pupae reared on normal hosts. Our results suggest that where garlic mustard is well established P. oleracea may be adapting to this plant by both improved larval performance and increased adult female oviposition preference for it.
外来植物可能成为本地食草动物的种群汇或进化陷阱。本地蝴蝶菜粉蝶（Pieris oleracea）在蒜芥（Alliaria petiolata）上产卵，但其幼虫在这种外来入侵植物上发育很差。我们研究了来自蒜芥生长良好地区和无蒜芥地区的单个雌性蝴蝶的产卵偏好及其后代的幼虫表现。这些数据用于评估蒜芥是否被纳入或排除在食谱之外。来自无蒜芥地区的雌性蝴蝶表现出广泛的偏好，其幼虫在蒜芥上的存活率很低，且幼虫存活率与母亲的偏好没有相关性。来自有蒜芥地区的雌性蝴蝶更喜欢蒜芥而非本地寄主，且幼虫在蒜芥上的存活率与母亲的偏好呈正相关。与在正常寄主上饲养的蛹相比，在蒜芥上存活的个体化蛹所需时间更长，体重轻30%以上。我们的结果表明，在蒜芥生长良好的地方，菜粉蝶可能通过提高幼虫表现和增加成年雌性对其产卵偏好来适应这种植物。
