[关键词]
[摘要]
辣椒疫病是困扰世界辣椒产业的一个严重而持久的问题,难以通过化学和农业手段加以控制。为筛选出具有防控疫病应用潜力的本地可培养有益细菌,从民勤盐碱化土壤中分离到42株生防细菌,采用对峙培养法进行筛选。 结果表明,菌株HMQ20YJ11对9种植物病原菌具有较强的拮抗活性。通过16S rRNA基因、gyrA基因和gyrB基因序列分析鉴定,菌株HMQ20YJ11为萎缩芽孢杆菌。 菌株HMQ20YJ11能够产生α-淀粉酶、氨、纤维素酶、吲哚-3-乙酸、果胶酶、蛋白酶、铁载体和溶解磷酸盐。在温室条件下,与未处理对照相比,菌株HMQ20YJ11可显著降低疫病的严重程度。 田间进行测试的结果表明,菌株HMQ20YJ11可显著降低疫病的严重程度,具有防治疫病的潜力。由此可看出,菌株HMQ20YJ11对植物病害具有拮抗作用,可作为潜在的生物防治菌剂加以应用。
[Key word]
[Abstract]
Pepper phytophthora blight is a severe and persistent problem in pepper industry worldwide, which is difficult to control throught chemical and agricultural means. The current study was designed to screen native cultivable rhizobacteria with potential applications for biocontrol of phytophthora blight, atotal of 42 strainswere isolated from salinized soil and screened by dual culture assay. Results revealed that the strain HMQ20YJ11 showed strong antagonistic activity against 9 plant pathogens. Based on 16S rRNA gene, gyrA gene and gyrB gene sequence analysis identified strain HMQ20YJ11 as Bacillus atrophaeus. Strain HMQ20YJ11 demonstrated many characteristics that are beneficial for plants, such as production of α-amylase, ammonia, cellulase, indole-3-acetic acid, pectinase, protease, siderophores, and phosphate solubilization. In planta application of strain HMQ20YJ11 significantly decreased phytophthora blight severity compared to untreated controls under greenhouse conditions. The strain HMQ20YJ11 was tested in the field and demonstrated a dramatic decrease in disease severity, suggesting strain HMQ20YJ11 as potential biocontrol candidate for phytophthora blight. These results suggested thatstrain HMQ20YJ11 could provide protection against plant disease and could be used as a potential agent for biological control.
[中图分类号]
S436.418.1
[基金项目]
甘肃省农业科学院农业科技创新专项(2020GAAS24、2021GAAS54);甘肃省农业科学院科技成果转化项目(2021GAAS-CGZH01);兰州市科技计划项目(2021-1-174);甘南州科技计划项目(2021-2)。