Abstract:After measuring the photosynthetic rate and transpiration rate of the leaves of seven-year field and two-year potted Malus pumila CV. Goldspur under different soil water and illumination conditions, together with the calculation of water use efficiency (WUE), the result showed that because photosynthetically active radiation (PAR) and soil water content (SWC) affected the photosynthetic rate and transpiration rate of Goldspur, they thus influenced WUE. The response of WUE to different illumination condition...