The effect of the degree of different photosynthetic characteristics leaf traits and chlorophyll content to shade the Paeonia rockii by two needles,four needles,six needles shading net,and compared with full illumination (CK)was studied.The result showed that solar radiation was decreased by 46.82％,60.94％,88.81％,and 1.25,1.03,0.88 times of the net photosynthetic rate,and the maximum net photosynthetic rate of 18.13 umol·m-2s-1 to compared with CK.The solar radiation was 761.54 umol·m-2s-1 at shade condition by two needles shading net.It was significantly affect on stomatal limitation,energy efficiency,leaf thickness,leaf weight ratio and relative water content,chlorophyll a and chlorophyll (a+b) content the net photosynthetic rate,leaf area and chlorophyll b content to shade the Paeonia rockii,and on the contrary of the stomatal conductance,intercellular CO2 concentration,transpiration rate and water efficiency.It was increased on the net photosynthetic rate,stomatal limitation,light efficiency,stomatal conductance,intercellular CO2 concentration and transpiration rate decreased,and chlorophyll a and b content,and alleviate the photoinhibition,and improve the photosynthetic function,and increased the accumulation of photosynthetic products to shade the Paeonia rockii with two needle shading net to compare with CK.%为研究不同遮阳程度对紫斑牡丹光合特性、叶片性状特征和叶绿素含量的影响,在大田条件下,分别设置2、4、6针遮阳网对紫斑牡丹遮阳,以全光照作为对照(CK)进行研究.结果表明:用2、4、6针遮阳网遮阳,和CK相比,太阳有效辐射分别降低46.82％、60.94％、88.81％,净光合速率分别是CK的1.25、1.03、0.88倍,最大净光合速率为18.13 umol·m-2s-1,出现在2针遮阳下,有效辐射为761.54 umol·m-2s-1.遮阳对紫斑牡丹气孔限制值、光能利用效率、叶厚度、比叶重和相对含水率、叶绿素a和叶绿素(a+b)含量影响差异极显著,对净光合速率、叶面积和叶绿素b含量影响差异显著,而对气孔导度、胞间CO2浓度、蒸腾速率、水分利用效率影响差异不显著.用2针遮阳网对紫斑牡丹遮阳,和CK相比,净光合速率、气孔限制值、光能利用效率提高,气孔导度、胞间CO2浓度、蒸腾速率降低,叶片叶绿素a、b含量增加,这样可以减轻光抑制,改善光合功能,增加光合产物积累.
展开▼
