【作者】 陈华保；

【导师】 吴文君；

【作者基本信息】 西北农林科技大学 ， 农药学， 2005， 硕士

【摘要】 本研究以高氏一号培养基为分离培养基,从67 份土样中分离到408 株放线菌。通过杀虫、杀菌、除草生物测定,筛选出2 株（编号为54^#和A₂C）菌株,其发酵液具有显著杀菌活性。主要研究结果如下: 1. 54^#和A₂C 菌株的生物活性研究结果表明54^#和A₂C 菌株发酵液无论在离体还是在活体条件下均对多种农业常见病原菌有很强的抑制作用。①54^#菌株发酵产物对苹果轮纹病菌、番茄灰霉病菌、油菜菌核病菌、葡萄灰霉病菌菌丝生长抑制中浓分别为45.02μg/ml、59.71μg/ml、51.54μg/ml、59.37μg/ml;对玉米大斑病菌、烟草赤星病菌和马铃薯干腐病菌的孢子萌发抑制中浓分别为169.95μg/ml、206.52μg/ml、286.29μg/ml;对枯草芽孢杆菌和金黄色葡萄球菌抑菌圈直径达到25mm 左右;盆栽试验表明,54^#菌株发酵原液对小麦白粉病的保护和治疗效果分别为78.8%和71.7%;田间防治番茄灰霉病和番茄叶霉病的效果分别为55.6%和74.8%。小杯法除草活性生测结果表明:54^#菌株发酵产物对反枝苋、稗草的主茎抑制中浓分别为106.07μg/ml和91.05μg/ml;但对种子萌发抑制作用不明显,抑制中浓分别为489.34μg/ml 和559.06μg/ml。②A₂C 菌株发酵产物对番茄早疫病菌、番茄灰霉病菌、小麦赤霉病菌菌丝生长抑制中浓分别为67.25μg/ml、40.87μg/ml、45.19μg/ml,对玉米大斑病菌、烟草赤星病菌和马铃薯干腐病菌的孢子萌发抑制中浓为104.12μg/ml、264.47μg/ml、305.05μg/ml。对金黄色葡萄球菌、大肠杆菌、假丝酵母菌、枯草芽孢杆菌的抑菌圈直径分别为30.1 mm、32.6 mm、28.5 mm、32.9 mm。A2C 菌株发酵原液盆栽防治小麦白粉病的保护和治疗效果分别达到90.3%和87.0%。田间防治番茄叶霉病和黄瓜霜霉病的效果分别为87.8%和59.8%。2. 54^#及A₂C 菌株具有很好的遗传稳定性,连续传代10代其发酵液活性没有明显变化。对于54^#及A₂C 菌株发酵液,除A₂C 菌株发酵液在pH=11 的碱性环境下活性有所下降外,在其它酸碱、紫外、温度以及光照条件下活性都无明显变化。这些结果表明54^#及A₂C菌株本身及其发酵产物具有很好的稳定性。3. 通过对54^#及A₂C 菌株的形态特征、培养特征和生理生化特征的观察,初步鉴定54^#菌株为链霉菌属金色类群中的禾粟链霉菌的1 个变种。A₂C 菌株为链霉菌属吸水类群中的烬灰吸水链霉菌的1 个变种。4. 通过紫外诱变对54^#菌株进行了初步选育,得到选育菌株159^#。其发酵液对枯草芽孢杆菌的抑菌圈直径比54^#菌株高出近一倍。159^#菌株具有很好的遗传稳定性,传代10代,发酵液对枯草芽孢杆菌的活性基本未发生改变。159^#菌株发酵液对温度、酸碱、紫外和光照也具有很好的稳定性。更多还原

【Abstract】 The primary studies isolated of actinomycetes from 67 sample in soil.408 strains of actinomycetes were obtained. From the screening of the insecticidal, fungicidal and herbicidal activities ,We found 2 strains of actinomycetes numbered 54^# and A₂C ,the metabolites of which had the strong fungicidal activities. The main results are as follows: 1.The results of mycelium growth rate showed that the value of EC₅₀ of the fermentation products of 54^# against Macrophoma kuwatsukai, Botrytis cintrea, Sclerotinia sclerotiorum Becry and Botryis cinerea Pers were 45.02μg/ml、59.71μg/ml、51.54μg/ml、59.37μg/ml, respectively.the value of EC₅₀ of the fermentation products of A2C against Alternaria solani, Botrytis cintrea and Gibberella zeae were 67.25μg/ml、40.87μg/ml、45.19μg/ml , respectively.The results of spore germination proved that the value of EC₅₀ of the fermentation products of 54^# and A₂C against Exserohilum turcicum, Alternaria longipes and Fusarium oxysporium were 169.95μg/ml、206.52μg/ml、206.52μg/ml and 104.12μg/ml、264.47μg/ml、305.05μg/ml. The results of pot tests against Blumeria guaminis indicated that the fermentation products of 54# and A₂C exhibited 78.8% and 90.3% protective efficacy, 71.7% and 87.0% therapeutic efficacy . The field trails results showed that the control efficacy of the fermentation products of 54^# against Pseudoperonospora cubensis and Fulvia fulva were 55.6% and 74.8%, the fermentation products of A₂C against Pseudoperonospora cubensis and Fulvia fulva were 87.8% and 59.8%. The results of tests of the herbicidal activity showed that the value of EC₅₀ of the fermentation products of 54^# against the caulis of Amaranthus and Echinochloa were 106.07μg/ml and 91.05μg/ml. 2. The test of stabilities indicated that the secondary metabolites of 54^# and A₂C strains were stable to acid, alkali ,temperature,illumination,ultraviolet radiation. when subculture ten generations,The fungicidal activity of secondary metabolites of 54^# and A₂C strains did not alter. 3. By means of observation on substrate mycelium, aerial mycelium, spore and sporothrix, Cultural characteristics, Biochemical and physiological characteristics, 54^# and A₂C strains were primarily identified as a variety for which the name S.graminearus emm.var. , S. cinereohygroscopicus.var., respectively. 4. Using 54# strain as an original strain, mutagenized with ultraviolet, 159# strain was obtained. This strain had a double activity as high as 54# strain against Bacillus subtilis. And it had good stabilities. The activity had not greatly altered either by several subcultures or any other temperature, acid and alkali, illumination and ultraviolet radiation.更多还原