Lobelia siphilitica plants that escape herbivory in time also have reduced latex production

Flowering phenology is an important determinant of a plant’s reproductive success. Both assortative mating and niche construction can result in the evolution of correlations between phenology and other reproductive, functional, and life history traits. Correlations between phenology and herbivore defence traits are particularly likely because the timing of flowering can allow a plant to escape herbivory. To test whether herbivore escape and defence are correlated, we estimated phenotypic and genetic correlations between flowering phenology and latex production in greenhouse-grown Lobelia siphilitica L. (Lobeliaceae). Lobelia siphilitica plants that flower later escape herbivory by a specialist pre-dispersal seed predator, and thus should invest fewer resources in defence. Consistent with this prediction, we found that later flowering was phenotypically and genetically correlated with reduced latex production. To test whether herbivore escape and latex production were costly, we also mea...开花物候（flowering phenology）是决定植物生殖成功的关键因素之一。选型交配（assortative mating）与生态位构建（niche construction）均可推动物候与其他生殖、功能及生活史性状间相关性的演化。物候与植食性防御性状（herbivore defence traits）间的相关性尤为常见，原因在于开花时序可使植物逃避植食性动物的取食。为探究植食逃避与防御是否存在相关性，我们以温室栽培的大花半边莲（Lobelia siphilitica L.，半边莲科Lobeliaceae）为材料，估算了其开花物候与乳汁产量间的表型相关性及遗传相关性。开花较晚的大花半边莲可逃避专性扩散前种子天敌的取食，故而其防御相关的资源投入理应更低。与该预测一致，我们观测到，开花较晚的个体乳汁产量更低，且该关联在表型与遗传层面均显著存在。为验证植食逃避与乳汁产量是否存在适应性代价，我们还开展了……