杨树与栅锈菌互作过程中光合、蒸腾作用变化研究

Changes of transpiration and photosynthesis in the interaction of poplar and Melampsora larici-populina Kleb

利用LI—6400便携式光合仪对受落叶松—杨栅锈菌Melampsora larici-populinaKleb.侵染后的杨树寄主的光合、蒸腾作用进行了动态监测。通过对不同抗性的杨树寄主在不同接种时间段的光合速率(Pn)、气孔导度(Gs)、胞间CO2浓度(Ci)以及蒸腾速率(Tp)活体监测后发现,在受到栅锈菌侵染后,抗病品种和感病品种的净光合速率、胞间CO2浓度均随接种时间的延长而逐渐下降。其中抗病品种内下降的幅度要比感病品种小。蒸腾速率在寄主受侵后开始逐渐下降直到开始产孢,但是在产孢后蒸腾速率就开始持续上升并超过健康寄主,并在产孢高峰达到最大值。气孔导度在接种后迅速增加,在产孢前后又开始大幅度的下降。这4个基本生理指标变化说明,栅锈菌侵染寄主后对寄主的光合、蒸腾作用均有影响,而且在亲合性组合中影响显著。

The photosynthesis and transpiration of poplar cultivars infected by Melampsora larici-populina Kleb. were monitored dynamically by LI-6400 Portable Photosynthesis System. The photosynthetic rate, CO2 concentration of intercellular, transpiration rate and stomatal conductance of poplar cultivars with different resistance were examined after the inoculation of Melampsora larici-populina Kleb. with different pathogenicity. The photosynthclic rate and CO2 concentration of intercellular declined after inoculation. The above two indexes in compatible combinations changed more significantly than in incompatible combinations. Although the transpiration rate reduced after the infection, it increased after the spore breakout. The stomatal conductance increased at the beginning of inoculation, and it had a conspicuous decline between the stages of spore breakout. The changes of four indexes indicated that the photosynthesis and transpiration of poplar cultivars were influenced by the infection of Melampsora larici-papulina Kleb. espcecially in compatible combinations.