【作者】 田小卫；

【导师】 吴文君；

【作者基本信息】 西北农林科技大学 ， 农药学， 2004， 硕士

【摘要】 本研究以西北农林科技大学农药研究所分离得到的一株放线菌代谢的活性物质为对象，对其农用抗菌谱、作用方式及安全性进行了初步的研究，主要研究结果如下： 采用抑制菌丝生长速率法，测定了 No.24 菌株发酵液对农业和食品中常见 20 种真菌进行抑菌活性测定。结果表明，No.24 菌株发酵液对多种真菌的菌丝生长均有强烈的抑制作用，在干物质含量为 2000mg?L-1 时，对菌丝生长的平均抑制率均在 70%以上。其中对玉米大斑病菌（Exserohilum turcicum）、苹果轮纹病菌(Macrophoma kawatsukai)和番茄灰霉病菌（Botrytis.cintrea）的 EC50 分别是 238.95 mg?L-1、146.87 mg?L-1 和365.34mg?L-1，对绿色木霉（Rhizopus oryzae）的 EC50 是 421.57 mg?L-1 。抑制孢子萌发法的毒力测定结果表明，对玉米大斑病菌、马铃薯干腐病菌的 EC50分别是 129.33 mg?L-1和 184.99 mg?L-1。 盆栽试验结果表明，No.24 菌株发酵液对黄瓜霜霉病、小麦白粉病、番茄灰霉病和烟草花叶病毒病均有一定的防效，保护作用均优于治疗作用。在 6000mg.L-1的浓度下，除了烟草花叶病毒病外，防效均在 60%以上。田间药效试验结果表明，No.24 菌株发酵液可以有效地控制黄瓜霜霉病、番茄灰霉病和小麦白粉病的进一步蔓延。 显微观察发现，No.24 菌株的次生代谢产物致使菌丝在带毒培养基上生长缓慢，菌丝均向上长，形成伞状结构，出现不规则膨大，菌丝粗壮，大量产孢；但对菌丝的正常产孢没有影响，产生的孢子仍可以正常萌发。对芽管的伸长具有强烈的抑制作用。 此外，试验也表明 No.24 菌株产生的活性物质具有较强的传导性，局部施药，对小麦白粉病的防治效果为 47.54%。其持效期可达 10d 左右。 对 14 种农作物的安全性测定表明，No.24 菌株发酵液可以初步认为在农作物上使用是安全的。更多还原

【Abstract】 This thesis studies on bio-activity of one actinomycetes isolated by institute of pesticide of NorthwestSci-tech University of Agriculture and Forestry. Agricultural antagonistic spectrum and action of modeand safety appraisement have been studied. The main results are as follows: By means of mycelium growth rate, the fermentation products of No.24 were tested against 20 kindsof fungi. The results showed that the fermentation products of No.24 have strong inhibition on variousfungi. At the concentration of 2000mg·L-1,the fermentation had an inhibition of rate more than70% .EC50 were 238.95 mg·L-1、146.87 mg·L-1、and 365.94 mg·L-1 respectively against Exserohilumturcicum、Macrophom kawatsukai and Botrytis.cintrea. The bioassay results of spore germination showedthat the fermentation had an inhibition against Exserohilum turcicum and Fusarium solani with an EC50 of129.33 mg·L-1 and 184.99 mg·L-1. At the concentration of 6000mg·L-1, the results of pot tests showd that the fermentation productshad a certain degree protective efficacy and therapeutic efficacy against Pseudoperonospora cubensis、Blumeria guaminis、Botrytis cintrea and TMV, The control efficiency were over 70%, and the protectiveefficacy was better than therapeutic efficacy.The field trails results indicated that thefermentation product of No.24 had a certain degree control effect against Pseudoperonospora cubensis、Blumeria guaminis and Botrytis.cintrea. The mode of action of No.24 secondary metabolize against disease fungi had been studied, the resultsshowd that the fermentation had a high degree inhibition on mycelium growth and spore germination. Themicroscope observation results showed that mycelium growed slowly and upward and formed umbrellastructure in the poisonous medium. Mycelium presented abnormal shap and crassitude. But It had noinfluence on producing spores and germinating. It had intensive inhibition on gemma elongation. Activity products of No.24 have strong conductibility, by means of local appling drugs, In pottest ,control effect against Blumeria guaminis is 47.54%; and it can persists 10d. Safety appraising had been studied on activity products of No.24, through appraising 14 agriculturalcrops, preliminarily judged that it was safe on agricultural crops.更多还原