Hanley M E, Fegan E L
School of Biological Sciences, University of Southampton, Bassett Crescent East, Southampton, SO16 7PX, UK.
Plant Cell Environ. 2007 Jul;30(7):812-9. doi: 10.1111/j.1365-3040.2007.01671.x.
Although the effects of herbivory on plant fitness are strongly linked to age, we understand little about how the timing of herbivory at the seedling stage affects growth and reproduction for plants that survive attack. In this study, we subjected six north-western European, dicotyledonous grassland species (Leontodon autumnalis, Leontodon hispidus, Plantago lanceolata, Plantago major, Trifolium pratense and Trifolium repens) to cotyledon removal at 7, 14 and 21 d old. We monitored subsequent growth and flowering (number of inflorescences recorded, and time taken for first flowers to open) over a 107 d period. Cotyledon removal reduced growth during establishment (35 d) for all species, and a further three exhibited reduced growth at maturity. Four species developed fewer inflorescences, or had delayed flowering after cotyledon removal. Although early damage (7 d old) had the greatest long-term effect on plant performance, responses varied according to the age at which the damage occurred and the species involved. Our results illustrate how growth and flowering into the mature phase is affected by cotyledon damage during different stages of seedling ontogeny, and we highlight the ways in which ontogenetic variation in seedling tolerance of tissue loss might impact upon plant fitness in mature plant communities.
尽管食草作用对植物适合度的影响与植物年龄密切相关，但对于在幼苗期遭受食草作用的时间如何影响存活下来的植物的生长和繁殖，我们了解甚少。在本研究中，我们对6种西北欧双子叶草原物种（秋季狮牙草、糙叶狮牙草、披针叶车前、大车前、红车轴草和白车轴草）在7日龄、14日龄和21日龄时去除子叶。我们在107天的时间里监测了后续的生长和开花情况（记录花序数量以及第一朵花开放所需时间）。去除子叶降低了所有物种在定植期（35天）的生长，另外还有3个物种在成熟时生长减缓。4个物种在去除子叶后形成的花序减少或开花延迟。尽管早期损伤（7日龄）对植物表现的长期影响最大，但反应因损伤发生时的年龄和所涉及的物种而异。我们的结果说明了在幼苗个体发育的不同阶段，子叶损伤如何影响植物进入成熟阶段的生长和开花，并且我们强调了幼苗对组织损失耐受性的个体发育差异可能影响成熟植物群落中植物适合度的方式。
