3种地被竹对大气臭氧胁迫的光合生理响应

Effects of Atmospheric Ozone Stress on Photosynthetic Physio- response of Three Dwarf Bamboos

摘要:

以美丽箬竹(Indocalamus decorus)、黄条金刚竹(Pleioblastus kongosanensis f.aureostriatus)、白缟椎谷笹竹(Sasa glabra f. albostriata) 3种优良地被观赏竹为试材,用开顶式同化箱(OTCs)模拟大气O₃浓度,研究了不同O₃浓度胁迫(环境背景大气、100 nL L^-1和150 nL L^-1)对竹子光合生理指标的影响。结果表明,随着大气O₃浓度的升高,美丽箬竹叶片叶绿素含量先升高后降低,黄条金刚竹呈相反变化规律,白缟椎谷笹竹呈下降趋势;它们的叶片类胡萝卜素含量变化不明显。美丽箬竹的Pn日均值先缓慢升高后降低,黄条金刚竹先略有升高后急剧降低,白缟椎谷笹竹逐渐降低;大气O₃浓度升高明显影响3种竹的光合参数日变化进程;大气O₃浓度为100 nL L^-1时,美丽箬竹的光合作用未受到抑制,黄条金刚竹和白缟椎谷笹竹则出现明显的抑制效应;大气O₃浓度达150 nL L^-1时,3竹种的光合生理都受到严重的伤害。耐受O₃胁迫能力存在种间差异,美丽箬竹明显高于黄条金刚竹、白缟椎谷笹竹。

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.