保护地土传病害枯萎病和疫霉病生防菌剂的田间试验

为了克服保护地栽培作物的连作障碍,针对筛选的拮抗引起土传病害的枯萎病菌和疫霉病菌的微生物菌种进行了混合生防菌剂的制备,测定了制备菌剂中的菌体数量和抑菌活性;在人工接种的条件下研究了制备菌剂的生防效果;在保护地中试验了混合菌剂对枯萎病和疫霉病的防效。结果表明:制备的单菌剂中含有的活菌体数量能达到108 cfu/g以上,混合菌剂中每个菌种的活菌体数量能达到105 cfu/g,并且菌剂的粗提物中存在明显的抑制枯萎病菌和疫霉病菌的抑菌物质。在人工接种盆栽试验中单菌剂和混合菌剂对枯萎病和疫霉病均有一定的防效,其中混合菌剂对两种病害的防效均达到80%以上。混合菌剂田间实验对枯萎病和疫霉病防效能达到70%以上。

Field Effects of Biocontrol Agents on Soil-borne fusariu Wilt and phytophthora Blight

In order to overcome continuous cropping barriers in the protected field,biocontrol agents were prepared with mixed microbial strains antagonistic to Fusarium and Phytophthora which cause soil-borne diseases.Microbial numbers and inhibiting activity of biocontrol agents prepared were measured.The control effects of biocontrol agents prepared on fusarium wilt and phytophthora blight was studied in the artificial inoculation pot and in the protected field,respectively.The results showed that the viable microbial number can separately reach 108 cfu/g in biocontrol agents with single microbial strain and 105 cfu/g of each strain in biocontrol agents with mixed strains.The crude extract of biocontrol agents was clearly observed with activity inhibiting Fusarium and Phytophthora.In the pot experiment of artificial inoculation,biocontrol agents with single microbial strain and mixed strains had the certain control effects on fusarium wilt and phytophthora blight,the control effects of the biocontrol agent with mixed strains on the two diseases could be more than 80%.The control effects of the biocontrol agent with mixed strains on fusarium wilt and phytophthora blight could be more than 70% in the experiment of protected field.