魔芋软腐病致病机理及其生物防治

Pathogenic Mechanism and Biological Control of Konjac Soft Rot Disease

[目的]报道国内外学者关于魔芋软腐病生物防治的研究成果。[方法]通过近几年国内外文献调研,综述国内外学者在致病机理和生物防治方面的研究进展,并就今后魔芋软腐病防治提出几点设想。[结果]在对软腐欧文氏菌病原菌致病机理的深入研究中,明确了软腐欧文氏菌的群体调节系统,即细菌可根据特定信号分子浓度监测周围环境中自身或其他细菌的数量变化,能启动菌体中相关基因的表达来适应环境中的变化;明确欧文氏菌有一系列分泌系统,系统Ⅰ将蛋白酶从细胞质分泌到胞外空间一步完成,系统Ⅱ可分2步分泌果胶酶和纤维素酶,在致病中起重要作用;果胶酶是致病过程中最重要的酶。近年来生物防治魔芋软腐病初见成效,主要是利用生防细菌、生防真菌和植物活性物质以及利用植物基因工程防治魔芋软腐病。[结论]该研究为软腐病的有效防治提供了新的思路和手段。

[ Objective ] The research results on biological control of konjac soft rot disease written by domestic and foreign scholars were reported. [ Method ] According to investigating domestic and foreign literatures in recent years, the research progress on pathogenic mechanism and biological control written by domestic and foreign scholars were reviewed and several assumptions on the control of konjac soft rot disease were put forward. [ Result] The population regulation system of Erwinia carotovora was determined through farther study on pathogenic mechanism of Erwinia carotovora pathogcny, that was, the bacteria could monitor the quantity change of itself or other bacteria on the surrounding environment according to the conch, of specific signal molecular and startup the related genes of bacteria to express to adapt changing environment. Erwinia carotovora had a series of excretion system. The system Ⅰ excreted protease from cytoplasm to extracellular and one step was taken in this process. The system Ⅱ excreted pectinase and cellulase by two steps, which was put an important role on pathogenic process. The pectinase was the most important enzyme in the pathogenic process. Initial success on controlling konjac soft rot disease by biological control was obtained in recent years and it was mainly using biocontrol bacteria, biocontrol fungi, plant active substance and plant genetic engineering for controlling konjac soft rot disease. [ Conclusion] The research provided new thoughts and means for controlling konjac soft rot disease effectively.