黄瓜枯萎病对黄瓜光合和水分生理特性的影响

Effect of Fusarium oxysporum f. sp. cucumerinum on photosynthesis and water physiological characteristics in cucumber

采用盆栽试验的方法,对黄瓜植株感染黄瓜枯萎病病原菌后不同发病级别的黄瓜叶片水分生理指标变化,以及连作土壤上施用有机肥与微生物有机肥后对不同处理黄瓜叶片水分生理指标的影响进行了研究。结果表明:植株在感染枯萎病病原菌后,叶片比叶重、叶绿素含量、净光合速率、气孔导度和蒸腾速率都显著降低,其中光合速率和气孔导度分别降低约80%和60%。随着植株感病程度的增加,叶柄胼胝质含量显著增加,导致了叶片含水量和叶片导水率的显著降低。叶片含水量、叶片导水率和叶柄胼胝质含量之间呈显著的负相关关系。施用微生物有机肥料能够抑制叶柄胼胝质形成,维持叶片导水率、叶片含水量和叶片的光合特性。在发生黄瓜连作障碍的土壤上施用含有特殊拮抗菌株的微生物有机肥后,可以缓解病原菌对植株水分生理代谢的影响。

Pot experiments were conducted by measuring leaf specific weight,photosynthesis,leaf hydraulic conductance and callose content in petioles of different pathological grade plants.The results obtained were as follows：leaf specific weight,chlorophyll content,net photosynthetic rate,stomatal conductance and transpiration rate decreased when plants were infected Fusarium oxysporum f.sp.cucumerinum,net photosynthetic rate and stomatal conductance decreased by about 80% and 60%,respectively.There were significantly negative relationships between leaf hydraulic conductance,leaf water content and callose content in petioles.In addition,callose content in petioles increased with increasing pathological grade,which resulted in a decrease in leaf water content and leaf hydraulic conductance.The application of microbial organic fertilizer could suppress callose formation,and maintain leaf hydraulic conductance,leaf water content and photosynthesis.Therefore,the formation of callose,when cucumber was infected fusarium wilt,restrained water transportation,decreased leaf water content and suppressed photosynthesis.And the application of microbial organic fertilizer could sufficiently alleviate the negative effects in photosynthesis and water relationship in plants.