Abstract:Under the climatic and ecological conditions of Hexi Corridor of Gansu Province, using nectarine variety ‘Zhongnong Jinhui’ as experimental material, we designed the differences of root restriction volume 135 L, 225 L, 360 L, 576 L and control 1 440 L(RV135, RV225, RV360, RV576 and RV1440) and investigated the growth, chlorophyll content, photosynthetic gas exchange parameters and fluorescence parameters of nectarine tree grown in Gobi greenhouse. The effects of root restriction on vegetative growth, photosynthetic and fluorescence characteristics of nectarine were studied. The results shown that: (1) compared with the control RV1440, the stem diameter and shoots length of RV135 and RV225 treatments were significantly reduced; the stem diameter of RV360 treatment was decreased significantly, while the shoot length had no significant effects; both parameters of RV576 treatment did not shown significant difference. (2) Compared with RV1440, the chlorophyll content and net photosynthetic rate, transpiration rate and stomatal conductance of RV135 and RV225 were significantly reduced, and the intercellular CO2 concentration was significantly increased at 14:00, however, RV360 and RV576 did not show differences. (3) Compared with RV1440, the JI phase fluorescence value of OJIP curve of nectarine leaves in root restriction treatments decreased significantly; at 14:00, the relative variable fluorescence difference (ΔVt) was less than 0 in K phase, and the relative variable fluorescence difference (ΔVt) of RV135 and RV225 was decreased significantly. The fluorescence chlorophyll specific activity parameters of RV135 and RV225 were higher in the absorption flux per reaction center (ABS/RC) and the dissipated flux per reaction center (DI0/RC), and were lower in the maximum photochemical efficiency (Fv/Fm) and the quantum yield (φE0) for electron transport (φE0) of PSⅡ. Compared with RV1440, comprehensive performance index PItotal of RV135 and RV225 were decreased by 34.9% and 27.1%, respectively, while the difference between RV135 and RV225 were not significant. It was found that proper root restriction could not only control the vegetative growth of nectarine trees, but also keep their photosynthetic characteristics and economic yield, and the optimal root restriction volume is 360 L, which provided a theoretical basis for root restriction cultivation of nectarine trees in greenhouse in gobi area.