Abstract: The photosynthetic and physiological characteristics, and diurnal variation of photosynthesis in leaves of grafted and seeded Ginkgo biloba were studied. The results showed that: 1) Maximum net photosynthetic rate(Pn), the light compensation point and the diurnal photosynthetic production yield of the grafted and double-grafted Ginkgo biloba were significantly higher than those of Ginkgo biloba seedling, which contributed to their prematurity and great yield. 2) The higher photosynthetic capacity of the grafted and double-grafted Ginkgo biloba was associated with their lower specific leaf area and higher leaf nitrogen per unit leaf area; However, their photosynthetic nitrogen-use efficiency was lower than that of Ginkgo biloba seedling. 3) The diurnal variation of Pn and stomatal conductance were ‘two-peaked’ curves. The rapid reduction of Pn at midday was due to high light, high temperature and low relative humidity, the main cause of which in Ginkgo biloba seedling was due to stomatal restriction factors, whereas, which was due to nonstomatal restriction factors in grafted and double-grafted Ginkgo biloba.

Key words: Ginkgo biloba L., Plant style, Photosynthesis