Institute of Evolutionary Biology and Environmental Studies, University of Zürich, Winterthurerstrasse 190, Zürich 8057, Switzerland.
Proc Biol Sci. 2011 Sep 7;278(1718):2598-603. doi: 10.1098/rspb.2010.2475. Epub 2011 Jan 26.
We used a selection of Arabidopsis thaliana mutants with knockouts in defence genes to demonstrate growth costs of trichome development and glucosinolate production. Four of the seven defence mutants had significantly higher size-standardized growth rates (SGRs) than the wild-type in early life, although this benefit declined as plants grew larger. SGR is known to be a good predictor of success under high-density conditions, and we confirmed that mutants with higher growth rates had a large advantage when grown in competition. Despite the lack of differences in flowering-time genes, the mutants differed in flowering time, a trait that strongly correlated with early growth rate. Aphid herbivory decreased plant growth rate and increased flowering time, and aphid population growth rate was closely coupled to the growth rate of the host plant. Small differences in early SGR thus had cascading effects on both flowering time and herbivore populations.
我们使用了一系列拟南芥突变体，这些突变体在防御基因中被敲除，以证明毛状体发育和硫代葡萄糖苷产生的生长成本。在生命早期，七个防御突变体中有四个的大小标准化生长率（SGR）明显高于野生型，尽管随着植物的生长，这种优势下降。SGR 是高密度条件下成功的良好预测指标，我们证实，在竞争中生长时，生长速度较快的突变体具有很大的优势。尽管开花时间基因没有差异，但突变体在开花时间上存在差异，这一特征与早期生长速度密切相关。蚜虫取食会降低植物的生长速度并延长开花时间，而蚜虫种群的生长速度与宿主植物的生长速度密切相关。因此，早期 SGR 的微小差异对开花时间和食草动物种群都有级联效应。
