【作者】 茹水江；

【导师】 郑重； 王汉荣；

【作者基本信息】 浙江大学 ， 植物病理学， 2008， 硕士

【摘要】 木霉是重要的生防菌,在植物病害生物防治中具有重要的应用价值。本文针对西瓜、茄子、白术等浙江省重要经济作物的土传病害,开展了木霉菌的筛选,获得对西瓜枯萎病、白术白绢病、茄子菌核病病菌高效拮抗的目标菌株T-6,并进行了该菌的生物学特性、种类鉴定、固体培养条件等研究,研制出木霉颗粒菌剂ST-6,并对其田间应用技术和效果进行初步评价。主要研究结果如下:（1）木霉菌的分离筛选:用诱捕法分离160个土样中,有68份土样分离出木霉,共获得木霉菌株98个。我们从中选取有代表性木霉菌株13个,并与西瓜枯萎病、白术白绢病、茄子和西兰花菌核病病菌进行离体拮抗作用测定,筛选出最有效的目标菌株T-6。对峙培养结果表明木霉菌T-6对白术白绢病菌、西兰花菌核病、西瓜枯萎病、茄子菌核病菌有很好的抑制作用。（2）对木霉菌T-6的生物学特性进行的研究,并进行种类鉴定。明确了木霉菌T-6的菌丝生长和孢子萌发最适温度为30℃;菌丝生长最适培养基为PDA;产孢最适培养基为OMA、偏酸条件下有利于该菌的生长和孢子的产生和萌发;明确其对不同碳源、氮源的利用情况。木霉菌T-6经鉴定为哈茨木霉（T.harzianumRifai）。（3）木霉生防颗粒菌剂ST-6的生产工艺的研究。经比较试验,选用直径0.2-0.4mm的碎米作为木霉ST-6固体培养载体,加水至含水量40-50%,灭菌后添加0.2%蔗糖、0.2%硝酸铵、0.1%KH₂ PO₄,4%接种量接种,在65-90%湿度、变温（28℃～24℃～26℃）条件下发酵培养7-8天,待菌丝及孢子布满固体培养载体后,以0.1%粘结剂D或0.4%粘结剂A作用粘结剂,米糠粉或麸皮粉作为包衣粉均匀吸附与固体培养载体外面,包衣后摊开,用常温气流风干后包装即成产品。（4）木霉生防颗粒菌剂ST-6的保质期及常用杀菌剂对其的影响。经测定木霉生防颗粒菌剂ST-6可在干燥、避光的室内自然常温下贮存16个月以上。测定了多菌灵等6种常用杀菌剂对木霉T-6和颗粒剂ST-6的影响。结果表明多菌灵、使百克对木霉T-6抑制作用较强,Ec50分别为0.2521 mg·kg-1和0.03948mg·kg-1,福美双对木霉T-6影响较小,甲霜灵-锰锌对木霉没有影响。不同杀菌剂对木霉生防颗粒剂ST-6抑制作用不同。其中多菌灵、甲基托布津、使百克3天后对ST-6萌发率和孢子产生量影响较大,但7天后对ST-6孢子产生量影响不是很大,而万霉灵、甲霜灵-锰锌、福美双对ST-6萌发率和孢子产生量基木无影响。（5）木霉生防颗粒菌剂ST-6的应用效果。测定了木霉生防颗粒菌剂ST-6对西瓜枯萎病、白术白绢病、茄子菌核病等病害的防治技术和防治效果,木霉颗粒剂ST-6 3g/株对西瓜枯萎病的、白术白绢病、茄子菌核病的小区防治效果分达73.62%、77.05%、69.39%,大田试验对西瓜枯萎病的、白术白绢病,茄子菌核病防治效果分别达72.96%、67.49%、70.12%,增产分别达到7.89%、5.07%、2.98%。（6）木霉生防颗粒菌剂ST-6对作物的安全性和生长、产量的影响。施用该颗粒菌剂对西瓜、黄瓜、甜瓜、番茄、茄子、白术六种作物安全,并能使植株粗壮,病害发生减轻,产量增加3～15%。更多还原

【Abstract】 Trichoderma species are an important fungi in the field of plant disease biocontrol.We isolated many Trichoderma strains to select some strains have good biocontrol roles against the soil-born diseases of watermelon,Atractgiodes macrocephaia and eggplant.Strain T-6 is a selected strain with strong antagonistic roles.We studied biology,identification and solid culturing condition of the strain T-6. Based on the study,the ST-6 granules agent was developed.The teclmiques and effect of ST-6 application in the field were also evaluated in this research.All the results are as the following:（1） The isolation and selection of Trichoderma strains.Ninety-eight Trichoderma strains were isolated through the pathogen induced method from 68 soil samples. Among them,13 strains were tested their antagonism against the plant pathogenic fungi,including Fusarium oxysporum of watermelon,Sclerotium rolfsii of Atractgiodes macrocephaia and Sclerotinia sclerotiorum of eggplant,on the dual culture in vitro.The results indicated the strain T-6 showed the strongest antagonistic against the tested fungi.（2） The research on biology and identification of strain T-6.The cultural temperate at 30℃is optimum for its hypha development and spores germination.The optimal media is PDA for hypha development,and OMA for spores formation.Hypha and spores develop better in the acidic environment.The growth of T-6 in different carbon and nitrogen sources was also studied.The strain T-6 was identified Trichoderma harzianum Rifai.（3） The production technology of ST-6 granules agent.The powdery of rice with 0.2-0.4 mm diameter and 40-50%humidity was the solid medium.After sterilization, 0.2%sucrose,0.2%NH₄NO₃ and 0.1%KH₂PO₄ were added into the sterilized powdery.The strain T-6 was inoculated by 4%of the solid medium,and cultured for 7-8 days with 65-90%humidity and 28℃～24℃～26℃fluctuant temperature.When the solid culture were enveloped by the T-6 culture,0.1%D or 0.4%A were added as a binders and bran was added as a coating agent.Then,the prepared agent was air-dryed at room temperature with airflow,and packed as the ST-6 granules agent.（4） The shelf-life of ST-6 and the effect of fungicide on ST-6 agent.ST-6 grains could be stored more than 16 monthes in room temperature under dry and dark environment. Six fungicides were tested for their virulence to T-6 and ST-6.Carbendazim and Prochloraz bad the strongest virulence with Ec50 as 0.2521 mg·kg^-1 and 0.03948 mg·kg^-1,respective.Thiram had little and metalaxyl-mancozeb had no effect on the strain T-6.Different fungicides had different roles to the ST-6 agent.After 3 days of the fungicides application,Carbendazim,Thiophanate-methyl and Prochloraz showed obvious effects on the and spore formation and germination of ST-6 agent.However, the effect on the spore formation was not significant after 7 days of the application. Diethofencarb,metalaxyl-mancozeb and thiram didn’t inhibit the germination and formation of ST-6 spores after the application.（5） The application effect of the ST-6 agent s.The application techniques and control effect of ST-6 agent on the diseases,including watermelon wilt,blight of Atractgiodes macrocephaia and white blight of eggplant,were tested in the field tests.When the ST-6 agent was applied at 3 g per plant in the field tests,the incidences of the three diseases decreased by 73.62%,77.05%and 69.39%,respectively.We also applied ST-6 agent to control the three diseases in farmer field.The effects of controlling diseases were 72.96%,67.49%and 70.12%,and the yield were increased by 7.89%, 5.07%and 2.98%for watermelon,Atractgiodes macrocephaia and eggplant.（6） The safty and effect of ST-6 agent application on the development and yield of crops.The application was safe for watermelon,cucumber,melon,tomato,eggplant and Atractgiodes macrocephaia.The plants grew better than control without ST-6 application,and the disease incidences reduced and the yields increased by 3-15%.更多还原