Oxygen isotopic composition (Δ¹⁸O_LW) of leaf water can help improve our understanding of how anatomy interacts with physiology to influence leaf water transport. Leaf water isotope models of Δ¹⁸O_LW such as the Péclet effect model have been developed to predict Δ¹⁸O_LWO, and it incorporates transpiration rate (E) and the mixing length between unenriched xylem water and enriched mesophyll water, which can occur in the mesophyll (L) or veins (L). Here we used two cell wall composition mutants grown under two light intensities and RH to evaluate the effect of cell wall composition on Δ¹⁸O_LW. In maize (Zea mays), the compromised ultrastructure of the suberin lamellae in the bundle sheath of the ALIPHATIC SUBERIN FERULOYL TRANSFERASE mutant (Zmasft) reduced barriers to apoplastic water movement, resulting in higher E and L and, consequently, lower Δ¹⁸O_LW. In cellulose synthase-like F6 (Cslf6) mutants and wildtype of rice (Oryza sativa), the difference in Δ¹⁸O_LW in plants grown under high and low growth light intensity co-varied with their differences in stomatal density. These results show that cell wall composition and stomatal density influence Δ¹⁸O_LW by altering the Péclet effect and that stable isotopes can facilitate the development of a physiologically and anatomically explicit water transport model.

中文翻译：

---

叶细胞壁特性和气孔密度影响叶水的氧同位素富集

氧同位素组成（Δ ¹⁸ Ø _LW）叶水可以帮助提高我们的生理与解剖相互作用如何影响叶水运理解。的叶水同位素模型Δ ¹⁸ ö _LW如皮克里特准效应模型已经发展到预测Δ ¹⁸ ö _LW O，和它结合蒸腾速率（ë）和未富集的木质部水和富集叶肉水之间的混合长度，这可以发生在叶肉（L）或静脉（L）中。在这里，我们使用下的两个光强度和RH生长2点细胞壁组成的突变体，以评估对Δ细胞壁组合物的效果¹⁸Ø _LW。在玉米（玉蜀黍），则木栓质薄片的在脂肪木栓质阿魏酰转移酶突变体（的维管束鞘遭到入侵的超微结构Zmasft）减少到质外体水的运动的障碍，导致更高的ë和大号，因此，降低Δ ¹⁸ ö _LW。在纤维素合酶样F6（Cslf6）突变体和水稻的野生型（稻），在Δ的差¹⁸ Ò _LW在高和低生长光强度下生长的植物中，气孔密度的差异会共同变化。这些结果表明，细胞壁成分及气孔密度影响Δ ¹⁸ ö _LW通过改变皮克里特准效果和稳定同位素可促进生理学的发展和解剖学上明确的水运输模型。