欧亚国际

摘要

    叶片内部气体空间与外在环境气体间的气体通量控制通过气孔控制实现。保卫细胞决定了气孔开口情况，保卫细胞必须工作来确保在光合作用（A）的CO2 摄入与水分缺失之间的适当平衡，较终影响植物水利用效率（WUE）。A和气孔导度（gs）强相关性记录很多，也经常被观测到，但此关系形成的潜在机制，可能是信号和代谢物，并不为所知。该综述中，我们评估了叶肉驱动的信号相关当前文献，该信号可能来通过叶肉碳通话来协调气孔行为。我们研究了不同代谢物的可能的作用，包括蔗糖和苹果酸盐（几个不同来源；包括保卫细胞合成）；新证据表明WUE提升是通过保卫细胞内的蔗糖操控机制来实现的。较后，我们讨论了目前可用的新型设备和工具来阐明叶协调CO2 需求和气孔行为的叶肉肉驱动信号，以便系统理解这些过程，这有助于鉴别可用于调控的潜在靶体，用以植物WUE和提升作物产量。

Mesophyll photosynthesis and guard cell metabolism impacts on stomatal behaviour

Summary

Stomata control gaseous fluxes between the internal leaf air spaces and the external atmosphere. Guard cells determine stomatal aperture and must operate to ensure an appropriate balance between CO2  uptake for photosynthesis (A) and water loss, and ultimately plant water use efficiency (WUE). A strong correlation between A and stomatal conductance (gs) is  well documented and often  observed, but  the underlying mechanisms,  possible signals and metabolites that promote this relationship are currently unknown. In this review we evalsuate the current literature on mesophyll-driven  signals that may coordinate stomatal behaviour with mesophyll carbon assimilation. We explore a possible role of various metabolites including sucrose and malate (from several potential sources; including guard cell photosynthesis) and new evidence that improvements in WUE have been made by manipulating sucrose metabolism within the guard cells. Finally we discuss the new tools and techniques available for potentially manipulating cell-specific metabolism, including guard and mesophyll cells, in order to elucidate mesophyll-derived signals that coordinate mesophyll CO2 demands with stomatal behaviour, in order to provide a mechanistic understanding of these processes as this may identify potential targets for manipulations in order to improve plant WUE and crop yield.

New Phytologist (2014) 203: 1064–1081

doi: 10.1111/nph.12945