银杏叶枯病对叶片光合及生理特性的影响

以江苏省东台国有林场健康银杏树和感染叶枯病银杏树为试验材料,通过测定叶片光合及生理指标的变化,以期从生理代谢角度认识和评价银杏叶枯病病害。结果显示,以健康银杏树健康叶(JSJY)为对照,叶枯病银杏树病害叶(BSBY)叶绿素含量、叶绿素荧光参数Fv、Fm显著降低(P0.05),但可溶性蛋白的含量显著升高(P0.05);BSBY与叶枯病银杏树健康叶(BSJY)叶片净光合速率(Pn)、最大净光合速率(Amax)及可溶性糖含量显著降低(P0.05)。同时,与JSJY和BSJY相比,BSBY黄酮类化合物含量分别降低了18.78%和13.93%(P0.05)。由此可见,银杏叶枯病会降低叶片可溶性糖含量,抑制叶片光合作用,一定程度上降低病害叶叶绿素荧光参数值和黄酮类化合物含量,从而降低叶片的品质,危害银杏树的生长。

Effect of Leaf Blight on Photosynthetic and Physiological Characteristics in Ginkgo biloba Leaves

In the present study,to understand and evaluate the Ginkgo leaf blight disease from the aspect of physical metabolism,healthy Ginkgo trees and leaf blight infected individuals from Dongtai state-owned for-est farm of Jiangsu Province were selected as the experimental material,and the effect of leaf blight on photo-synthetic and chlorophyll physiological characteristics in Ginkgo biloba leaves was estimated. The data showed that in the infected leaves of leaf blight Ginkgo trees ( BSBY) the chlorophyll content,Fv and Fm decreased sig-nificantly (P<0.05),whereas the soluble protein content increased significantly (P<0.05) compared with those of the healthy Ginkgo tree (JSJY).The net photosynthetic rate (Pn),maximum net photosynthetic rate ( Amax) and soluble sugar content of BSBY and healthy leaves of leaf blight Ginkgo trees ( BSJY) decreased significantly compared with those of the healthy Ginkgo tree (JSJY) (P<0.05).Simultaneously,compared with JSJY and BSJY,the flavonoid content of BSBY decreased by 18.78% and 13.03% (P>0.05).These data ob-tained here indicated that Ginkgo leaf blight resulted in the decline of soluble sugar content and photosynthesis. To some extent,it can reduce the chlorophyll fluorescence parameters and flavonoid content of infected leaves, thereby lowers the quality of the leaves and jeopardizes the growth of Ginkgo tree.