根肿病菌侵染时期与浓度对寄主生长特性及抗性的影响

Effects of Plasmodiophora brassicae Infection Time and Concentration on Growth Characteristics and Resistance of the Host

【目的】为探讨根肿病菌接种浓度与时期对寄主发病的交互作用及根肿病菌侵染后寄主的抗性响应。【方法】通过苗期盆栽试验,系统地研究了接种根肿病菌浓度(105、106、107、108 cfu/mL)及时期(0、10、20 d)对白菜发病率及防御酶活性的影响。【结果】发病率及病情指数与接种根肿病菌浓度呈正相关,108 cfu/mL为最佳侵染浓度,白菜幼苗出现第一片真叶后10 d接种侵染效果最佳。根肿病侵染后,根肿病发病程度与呼吸速率和气孔导度呈正相关,根系活力随病情指数先升高后降低,植株受根肿病侵染后光合作用降低,呼吸作用增强,植物生长受抑制;防御酶POD、PAL、PPO与发病率呈负相关,丙二醛含量与发病率呈正相关,植株抵抗病害能力降低。【结论】研究为根肿病的侵染和防控提供参考。

[Objective]To inquire into the Plasmodiophora brassicae spores inoculation concentration and period for the host,interaction and the root of the disease resistance of Plasmodiophora brassicae infection after the host response.[Methods]This study based on the seedling pot experiment,systematically studied the concentration of bacteria inoculated spores(105,106,107,108 cfu/mL)and period(0 d,10 d,20 d)impact on incidence of cabbage and defense enzyme activity.[Results]The results showed that there was a positive correlation between the incidence and the disease index and the concentration of inoculated disease spores 108 cfu/mL was the best infection concentration,and the infection effect of inoculated Chinese cabbage seedlings was the best 10 days after the first true leaf appeared.After disease spores infection,the incidence of clubrotic disease was positively correlated with respiratory rate and stomatal conductance.Root activity increased and decreased with the disease index first.After disease spores infection,photosynthesis decreased,respiration increased and plant growth was inhibited.Defense enzymes POD,PAL and PPO were negatively correlated with the disease incidence,while malondialdehyde content was positively correlated with the disease incidence,and plant resistance to disease was reduced.[Conclusions]This study provided references for Infection and prevention of clubroot disease.