Abstract:The effect of ozone stress on the photosynthetic physiological of three dwarf bamboos, such as Indocalamus decorus, Pleioblastus kongosanensis f.aureostriatus and Sasa glabra f. albostriata were studied. Three levels of ozone concentrations, including basic concentration of environment, 100 nL L-1and 150 nL L-1, were simulated by using an open-top chamber (OTCs) technique. The results showed that the chlorophyll content in Indocalamus decorus leaves increased at first and then decreased with the ozone concentration increased, while that in Pleioblastus kongosanensis f.aureostriatus showed opposite change, and that in Sasa glabra f. albostriata declined. The changes in carotenoid content of three dwarf bamboos leaves were not obvious. The daily net photosynthetic rate (Pn) of Indocalamus decorus increased at first and then decreased, while that of Pleioblastus kongosanensis f.aureostriatus increased slightly at first and then decreased rapidly, and that of Sasa glabra f. albostriata decreased. The daily changes of photosynthetic parameters in three dwarf bamboos were obvious with ozone concentration increment. Under 100 nL L-1 ozone, the photosynthesis of Indocalamus decorus did not inhibit, but those in Pleioblastus kongosanensis f. aureostriatus and Sasa glabra f. albostriata inhibited obviously, while 150 nL L-1 ozone caused serious damage to their photosynthetic physiological metabolism. In general, Indocalamus decorus showed higher tolerance to ozone than another bamboo.
