模拟酸雨胁迫对茶树幼苗生长和光合生理的影响

Effects of Simulated Acid Rain Stress on the Growth and Photosynthetic Physiology of Tea Seedlings

茶是世界三大饮料之一,并且茶树在中国被广泛种植。酸雨是中国乃至全球面临的主要环境问题,本研究选用一年生茶树幼苗作为实验材料,品种为湘妃翠,采用盆栽的方法培养,通过模拟pH值2.5、pH值3.5、pH值4.5酸雨以及自来水(pH值6.5)作为对照对茶树进行全喷淋,探究模拟酸雨对茶树幼苗生长状况和光合生理的影响。结果表明pH值4.5模拟酸雨对茶树幼苗生长有一定促进作用,pH值2.5模拟酸雨对茶树幼苗生长具有抑制作用。茶树幼苗SPAD值(叶绿素相对含量)、以及叶绿素荧光参数Fv/Fm(PSⅡ最大光能转换率)、Fv/Fo(PSⅡ潜在活性)在pH值2.5酸雨胁迫下与对照组相比都显著降低,Fo(初始荧光产量)则显著增大。由此说明pH值2.5模拟酸雨对茶树幼苗具有较强的胁迫作用,pH值4.5模拟酸雨对茶树幼苗生长有促进作用。

Tea is one of the three largest beverages in the world,and tea trees are widely cultivated in China.The annual seedlings of tea were selected as experimental materials and cultivated in pots,the variety is Xiangfeicui.The effects of simulated acid rain on tea plant growth status and photosynthetic physiology were investigated by simulating pH 2.5,pH 3.5,pH 4.5 acid rain and tap water(pH 6.5).The results showed that pH 4.5 simulated acid rain had a certain promotion effect on the growth of tea plant,pH 2.5 simulated acid rain had inhibitory effects on the growth of tea seedlings.Compared with the control group,the SPAD value,the Fv/Fm(maximal photochemical efficiency of PhotosystemⅡ(PSⅡ))and the Fv/Fo(potential activity of PSⅡ)of tea seedling decreased significantly under the acid rain stress of pH 2.5 and Fo(initial fluorescence yield)increased.The results showed that pH 2.5 simulated acid rain had strong stress on tea plant,but pH 4.5 simulated acid rain could promote the growth of tea plant.