四川松树内生拟盘多毛孢的多样性及其防病效果

Diversity traits of endophytic Pestalotiopsis from pine trees in Sichuan and its control effect

【目的】对四川松树内生拟盘多毛孢Pestalotiopsis的生态分布及其对松树病害的防治效果进行分析,为松树病害无公害治理提供理论与实践基础。【方法】对分布于四川的松树内生拟盘多毛孢的多样性进行调查统计,分析树种、松树组织、海拔和季节对内生拟盘多毛孢定殖率、Shannon-Weiner指数和相似性指数的影响。在此基础上,筛选对松落针病菌、烂皮病菌、赤枯病菌有拮抗作用的内生拟盘多毛孢,浸渍法检测其对松针的致病性,采用喷雾法和针刺法分别对室内盆栽湿地松苗接种拮抗菌和3种病原菌,计算发病率、病情指数和防治效果。【结果】湿地松、马尾松、火炬松中内生拟盘多毛孢的多样性明显高于华山松和云南松,内生拟盘多毛孢在针叶中的分布多于枝和干,其多样性在海拔较低地区（400-600 m）相对较高,不同季节则以春季多样性最高。此外,散沫拟盘多毛孢（P.lawsoniae）、小孢拟盘多毛孢（P.microspor）和石楠拟盘多毛孢（P.photiniae）对松落针病菌、松烂皮病菌、松赤枯病菌3种病原均有拮抗作用,抑制率达38.49%-77.42%,其中P.lawsoniae的作用最为明显,且在致病性测定中对松针无伤害作用。室内对湿地松苗病害的防治试验中,P.lawsoniae孢子原液及稀释液（50倍液和500倍液）对3种病害均表现出了较好的防治效果,防治效果达40.90%-89.77%。【结论】松树内生拟盘多毛孢资源丰富,对松树病害具有生物防治潜力,其中P.lawsoniae对松树落针病、烂皮病和赤枯病具有良好的生防前景。

【Objective】Ecological distribution of endophytic Pestalotiopsis from pine species in Sichuan and its control effect on pine diseases were analyzed to provide theoretical and practical basis for pollutionfree control of pine diseases.【Method】The diversity of endophytic Pestalotiopsis from pine species in Sichuan was investigated,and the effects of species,tissues,altitudes,and seasons on colonization rate,Shannon-Weiner index,and coefficient similarity of endophytic Pestalotiopsis were analyzed.Then,endophytic Pestalotiopsis with resistance against Lophodermium pinastri,Cenangium ferruginosum and Pestalotiopsis funereal were screened.The pathogenicity of endophytic Pestalotiopsis was determined by impregnation method.The antagonistic fungus and pathogen were inoculated in Pinus elliotii by spraying and needlepunching methods.Incidence,disease index,and control effect were also calculated.【Result】Endophytic Pestalotiopsis in Pinus elliotii,Pinus massoniana,Pinus taeda had significantly higher diversity than thatin Pinus armandii and Pinus yunnanensis.Distribution of endophytic Pestalotiopsis was more in needles than in branches and stems.Highest endophytic diversity was found in low altitude（400-600 m）in spring.Endophytic P.lawsoniae,P.microspore and P.photiniae showed antagonistic effect against three tested pine pathogens（L.pinastri,C.ferruginosum and P.funereal）with inhibition rates of 38.49%-77.42%.P.lawsoniae was the most effective one without injure effect on needles in the pathogenicity determination.In the controlled experiment in laboratory,the spore stock solution and diluent solution（50and 500times）of P.lawsoniae had positive control effects against all three diseases with inhibition rates of40.90%-89.77%.【Conclusion】The endophytic species of Pestalotiopsis from the pine species were rich and potentially functional against pine diseases.P.lawsoniae was a good candidate for the bio-control of the three pine diseases（L.pinastri,C.ferruginosumand P.funereal）.