Abstract:To further explore the water regulation mechanism of clonal plant and its effects on carbon assimilation and excitation energy distribution under water stress, the pair of strawberry (Fragaria×ananassa) ramets was utilized (the elder ramet was referred as mother and the other as daughter), in which the stolons between ramets was either cut (unconnected group) or left intact (connected group). At first, the daughter ramet in each pair was well watered and the mother ramet was exposed to soil water deficit. Four days later, the connected group was further subdivided into two groups, and part irrigated daughters were continually watered, and the other daughters began to suffer from soil water shortage gradually. Our results reveal that soil drying caused leaf dehydration in mother ramets and significantly decreased its photosynthetic rates and stomatal conductance. The well-watered daughter ramets in connected groups alleviated the water stress in mother ramets effectively. When the well-watered daughter ramets in the connected group began to dry gradually, the water stress of their connected mother ramets was significantly aggravated. Water uptake of stressed mother ramet was dependent on the decrease in water potential and enhancement of osmotic adjustment of its own. Though soil drying resulted in a substantial accumulation of ABA in water stressed ramets, but there was no ABA increasing in connected ones. And the stomatal conductance had the similar changing tendency with leaf ABA content. Accordingly, we concluded that: (1) Water translocation between the connected ramets may be determined by the gradients in water potential; (2) ABA produced in water-stressed ramet could not be delivered to the adjacent and connected ramet and affect its stomatal behavior; (3) Under heterogeneous wet conditions, water physiological integration between clonal ramets would significantly improve the carbon assimilation of entire clonal system and excited energy utilizing efficiency of PSⅡ.