关键词: 团花, 热耗散, 滇南风吹楠, 光合作用, 绒毛番龙眼, 幼苗, 热带雨林树种

Abstract: The study showed that water stress decreased the net photosynthetic rate (P_n),stomatal conductance (G_s),T_r transpiration rate (T_r),maximum fluorescence (F_m),ratio of variable to maximum fluorescence (F_v/F_m),and actual activities of PSⅡ (ФPSⅡ),but increased the minimal fluorescence (F_o).The alterations of test parameters differed with grape stocks.Under adequate water supply and mild water stress,the P_n of 3309C was higher than that of 1103P and 420A,while the chlorophyll fluorescence parameters of these three stocks changed a little.Under moderate water stress,the P_n of 1103P was higher than that of 420A and 3309C,the F_o of 3309C increased by 17.1% while F_v/F_mdecreased by 8.5%,and the F_o of 1103P increased by 6.8% while F_v/F_m decreased by 5.8%.Under severe water stress,the P_n of 1103P was the highest (5.6 μmol·m^-2·s^-1),which was 24% higher than that of 3309C,and the water use efficiency of 1103P was about 1.95 times as high as that of 3309C.The F_o of 3309C increased by 36.2% while F_v/F_m decreased by 20.1%,and the F_o of 1103P increased by 9.9% while F_v/F_mdecreased by 10.2%.It was implied that there was a close correlation between drought-resistance and the alteration of photosynthetic characters and chlorophyll fluorescence parameters,of which,the correlation index of F_v/F_m and P_n was the highest (r=0.9883).

Key words: Anthocephalus chinensis, Heat dissipation, Horsfieldia tetratepala, Photosynthesis, Pometia tomentosa, Seedlings, Tropical rain forest tree species