Effects of soil rewatering on mesophyll and stomatal conductance and the associated mechanisms involving leaf anatomy and some physiological activities in Manchurian ash and Mongolian oak in the Changbai Mountains

Publication date: Available online 19 September 2019Source: Plant Physiology and BiochemistryAuthor(s): Kai Zhu, Fenghui Yuan, Anzhi Wang, Hong Yang, Dexin Guan, Changjie Jin, Hongxia Zhang, Yushu Zhang, Jiabing WuAbstractThe recoveries of mesophyll (gm) and stomatal conductance to CO2 (gsc) after soil rewatering have received considerable attention in recent years, but the recovery mechanisms involving leaf anatomy and physiological activities are poorly understood. Moreover, it is also unclear whether leaf gas-phase conductance (gias) or liquid-phase conductance (gliq) is the main factor promoting gm recovery. By simultaneously using gas exchange and chlorophyll fluorescence, we measured the recoveries of gm and gsc in saplings of Manchurian ash (Fraxinus mandshurica Rupr.) and Mongolian oak (Quercus mongolica Fish. ex Ledeb) exposed to two initial water stress (medium water stress, MW, and severe water stress, SW) and following rewatering. Furthermore, leaf anatomical characteristics and the activities of aquaporin (AQP) and carbonic anhydrase (CA) were measured to explain the mechanisms of gm and gsc recoveries. The results showed that (i) both gm and gsc were partly recovered after rewatering, and the recoveries decreased with initial water stress in both species. (ii) The gm recovery was much greater in Mongolian oak than in Manchurian ash, while the gsc recovery was much greater in Manchurian ash. Consequently, the photosynthesis recovery in Manchurian ash was mostly a...
Source: Plant Physiology and Biochemistry - Category: Biochemistry Source Type: research