青枯菌侵染广藿香的致病因素及寄主植物相关酶活性分析

Analysis of Pathogenic Factors of Ralstonia solanacearum to Pogostemon cablin and Related Enzyme Activity of Host Plant

[目的]探讨青枯菌不同接种体诱导后,广藿香表型的变化,并考察诱导后寄主植物体内POD酶活性的变化。[方法]以青枯菌不同接种体(菌体、粗毒素、菌液)进行侵染试验,观察侵染1~7 d后植株表型的变化。利用紫外分光光度法进行POD酶活性的测定。[结果]在含菌体的培养基上,大部分广藿香植株没有明显的发病症状;而菌液与粗毒素处理组,植株茎叶逐渐萎蔫。POD酶活性测定结果表明,未经诱导的对照植株酶活性较低,7 d内变化不大;经诱导处理的植株体内POD酶活性均升高,菌液组升幅最大,粗毒素组次之,菌体组升幅最小。[结论]青枯菌胞外分泌物是青枯菌致病的重要因素,诱导的广藿香体内POD酶活性呈动态变化,上升的幅度与接种体的致病性呈正相关。

[Objective] The research aimed to investigate the phenotype changes of Pogostemon cablin after induction of different inoculums of R.solanacearum,and investigate the changes of POD enzyme activity in host plants after induction.[Method]The changes of plant phenotype were observed after 1-7 days of infection with different inoculum（bacteria,crude toxin,bacteria liquid） of R.solanacearum.The enzyme activity of POD was determinated by UV-Spectrometer.[Result]In the culture medium containing the bacteria,most of the plant of P.cablin had no obvious symptoms;and bacteria liquid and crude toxin treatment group,plant stems and leaves gradually wilted.The results of POD enzyme activity showed that the enzyme activity of the control plants without induction was lower,and there was little change within 7 d.The activity of POD was increased in the inoculated plants,the increase of the bacteria liquid was the highest,the crude toxin group was the second,and the bacteria group had the smallest increase.[Conclusion]The extracellular secretion of R.solanacearum is an important pathogenic factor of R.solanacearum,and the activity of POD enzyme in the wide range of patchouli is dynamic,and the magnitude of the increase is positively correlated with the pathogenicity of the inoculum.