土壤pH对芸薹根肿菌侵染及病害发生的影响  

Effects of pH on Plasmodiophora brassicae infection and disease development

作　　者：班洁静 侯明生[1] 蔡丽[1] 

机构地区：[1]华中农业大学植物科技学院,武汉430070

出　　处：《植物保护》2015年第6期55-59,共5页Plant Protection

基　　金：公益性行业(农业)科研专项(201003029)

摘　　要：通过设置不同 pH 梯度,研究土壤 pH 对根肿菌侵染及病害发生的影响。结果表明：土壤酸性时病菌侵染速度快,碱性时慢,而强酸性和碱性土壤条件则抑制孢子萌发；pH 为6.0时最有利于根肿菌休眠孢子萌发,萌发率最高,为53.96%；碱性条件可使初级原生质团变形凝结成球状,不能正常分裂或延迟形成游动孢子囊,从而不利于根肿菌侵染。白菜发病率与病情指数随 pH 升高,呈先上升后下降趋势。其中,pH 为5.0时,发病率和病情指数最高,pH 7.0～8.0时发病轻。因此,适宜的偏酸性环境条件下,通过作用于病菌休眠孢子萌发和侵染,提高病害危害程度,而中性或碱性条件干扰该过程并降低病害发生。A series of pH gradients were set up in order to investigate the effects of pH on Plasmodiophora brassicae in-fection and disease development.The results indicated that P .brassicae infection speed was higher under the acid condi-tions than under alkaline conditions.The highest germination rate of spore was 53.96% at pH 6.0.However,strong acidic and alkaline conditions inhibited germination of resting spores.Alkaline condition could make primary pro-toplasts deformed and condensed into globular shape.The primary protoplasts could not divide properly or delayed forming a zoosporangium.So the infection of P .brassicae was suppressed.Incidence and disease index increased with pH,with the highest level at pH 5.0,followed by the decrease.The incidence and disease index were lower at pH 7.0-8.0.So,the suitably low pH could promote the disease by acting on the resting spore germination and infection. However neutral or alkaline conditions might interfere with this process and reduced disease development.

关 键 词：十字花科蔬菜根肿病 芸薹根肿菌 土壤 PH 

分 类 号：S436.341.19[农业科学—农业昆虫与害虫防治]