Department of Ecology and Evolution, State University of New York, Stony Brook, New York 11794 USA.
Am J Bot. 2000 Mar;87(3):412-7.
Theoretical considerations have suggested that there may be differences in photosynthetic nitrogen use efficiency (PNUE) among plants that use different biochemical variants of C(4) photosynthesis. To test this hypothesis we examined the leaf nitrogen content and photosynthetic rates of six grass species (three of C(4) subtype NAD-ME and three of C(4) subtype NADP-ME) grown over a wide range of nitrogen supply. While there were significant differences among the species in various traits, there were no consistent differences between the C(4) subtypes in either leaf nitrogen content at a given level of nitrogen supply or in the leaf nitrogen-photosynthesis relationship. We suggest that species-level variation in photosynthetic nitrogen use efficiency among C(4) species is large enough to mask any differences that may be due to C(4) subtype.
理论上认为，利用不同生化类型 C4 光合作用的植物之间可能存在光合氮利用效率（PNUE）的差异。为了验证这一假设，我们在广泛的氮供应范围内研究了六种草种（三种 NAD-ME 型 C4 和三种 NADP-ME 型 C4）的叶片氮含量和光合速率。尽管在不同的性状上，物种间存在显著差异，但在给定氮供应水平下叶片氮含量或叶片氮-光合作用关系方面，C4 亚型之间没有一致的差异。我们认为，C4 物种之间光合氮利用效率的种间变异幅度足以掩盖可能由于 C4 亚型引起的任何差异。
