中文摘要：

研究植物碳（C）氮（N）磷（P）化学计量特征,有助于了解C、N、P元素的分配规律和确定限制植物生长的元素类型,理解生长速率调控的内在机制。该研究基于盆栽施肥试验,测定不同N、P供应水平下拟南芥（Arabidopsis thaliana）叶片的生物量和C、N、P含量,分析拟南芥的限制元素类型、验证生长速率假说、探讨N、P的内稳性差异和C、N、P元素间的异速生长关系。主要结果如下：盆栽试验基质中限制元素是P,施N过多可能引起毒害作用;拟南芥的生长符合生长速率假说,即随着叶片N：P和C：P的增加,比生长速率显著减小;叶片P含量存在显著的调整系数（3.5）,但叶片N含量与基质N含量之间无显著相关;叶片N和P含量具有显著的异速生长关系,但不符合N-P3/4关系,施P肥导致表征N、P异速生长关系的幂指数（0.209）显著低于施N肥处理（0.466）。该研究首次基于温室培养实验分析了拟南芥C、N、P的化学计量特征及其对N、P添加的响应,研究结果将为野外研究不同物种、群落或生态系统的化学计量特征提供参考。

英文摘要：

Aims Arabidopsis thaliana, a widely used model organism in plant biology, is an ideal plant to test the growth rate hypothesis （GRH） and homeostasis theory about plant nutrition. Our objectives are to test i） whether GRH applies to this plant species, ii） how leaf nitrogen （N） and phosphorus （P） of A. thaliana follow the homeostasis theory and iii） whether the allometric relationship between leaf N and P content is consistent with the 3/4 power function （N-P3/4） for individual plant species. Methods Based on a pot experiment in a phytotron with N and P fertilizer additions, we measured the leaf car- bon （C）, N and P content and leaf biomass ofA. thaliana. Specific growth rate （mg·mg-1·d-1） was the leafbiomass increment divided by the initial biomass at planting, and by the days after planting. The homeostasis of plant ele- ments is indicated by the exponent （reciprocal of the regulation coefficient） of the power function of leaf nutrient against soil nutrient concentrations. Important findings P is the limiting nutrient of the culture substrate for A. thaliana, while N fertilization could cause toxic effects in cases of excessive N uptake. The growth ofA. thaliana is consistent with GRH--the specific growth rate decreases with increasing leaf N：P or C：P. Leaf P content shows a significant regulation coefficient （3.51） （leaf-P-substrate-P1/3.51）, but leaf N content has no significant relationship with substrate N. There is a sig- nificant allometric relationship between leaf N and P content, which is inconsistent with the 3/4 power function （N-p3/4）. The power exponent （0.209） between leaf N content and leaf P content in the P fertilization treatments is significantly lower than the exponent （0.466） in the N fertilization treatments, suggesting that fertilization may affect the allometry between nutrients. Our findings can offer reference for future field studies on plant ecological stoichiometry at scales from species to community to ecosystem.