摘要
由交替链格孢(Alternaria alternata)引起的烟草赤星病是烟草生长中后期重要的叶部病害,直接影响烟叶的产量和品质。为开发烟草赤星病的生防制剂,对生防菌XNB-01进行了多相分类鉴定,并通过盆栽试验、粗提物的抑菌机理等研究,进一步阐明了XNB-01的生防机理。皿内对峙结果表明,XNB-01对交替链格孢的抑菌半径达到11.0 mm。菌株XNB-01短杆状,与Paenibacillus polymyxa ATTCC 842相似性为98.63%。次生代谢产物检测结果表明,XNB-01可以分泌多种真菌细胞壁降解酶,并具有溶解有机磷、解钾的能力。盆栽试验结果表明,XNB-01在1×10^(8)CFU/mL的施用浓度下显著增加了烟草幼苗的株高、鲜质量和干质量;在1×10^(9)CFU/mL的施用浓度下显著降低了烟草赤星病的病情指数,防效为60.94%,与菌核净(65.33%)相当。此外,XNB-01的胞内粗提物可抑制交替链格孢菌丝的生长和孢子萌发,使菌丝膨大,孢子皱缩。经200μg/mL XNB-01胞内粗提物处理后,峰值处的胞外电导率、核酸和蛋白质泄漏量分别是对照组的2.97、1.83、8.28倍,丙二醛含量比对照升高1.36倍。综上所述,P.polymyxa XNB-01具有防治烟草赤星病的生防潜力。
Tobacco brown spot,caused by Alternaria alternata(Fr.)Keissl,is a highly detrimental fungal disease that significantly affects the quantity of tobacco.In order to screen effective candidate biocontrol agents against A.alternata,the XNB-01 was classified and identified using polyphasic classification techniques,and the biological control mechanism of XNB-01was further elucidated by pot-experiment and crude extract inhibition test.The plate confrontation test showed that XNB-01 exhibited inhibitory activity against A.alternata,forming an inhibition zone with a radius of 11.0 mm.Strain XNB-01 was identified as a short rod-shaped bacterium,sharing 98.63%similarity with Paenibacillus polymyxa ATTCC 842.The secondary metabolite assay showed that XNB-01 produced various extracellular hydrolytic enzymes,and exhibited the organic phosphorus and potassium solubilization abilities.In the pot-experiment,treatment with XNB-01 at the application concentration of 1×10^(8)CFU/mL significantly increased the tobacco seedling growth in terms of plant height,fresh mass and dry mass,treatment with XNB-01 at 1×10^(9)CFU/mL significantly reduced the disease index of tobacco brown spot,and the biocontrol efficacy was 60.94%,comparable to that of myclobutanil(65.33%).The crude extract inhibited the mycelial growth and spores germination of A.alternata and changed the morphology of spores and mycelium.The crude extracts of XNB-01 resulted in a 2.97-fold increase in extracellular conductivity,a 1.83-fold and 8.28-fold increase in nucleic acid and protein leakage,and a 1.36-fold increase in malondialdehyde content in A.alternata compared to the control group.To sum up,P.polymyxa XNB-01 exhibits promising biocontrol potential for management of tobacco brown spot disease.
作者
陈娜
陈婧
闵琪茹
安德荣
文俊明
杨照
王阳
CHEN Na;CHEN Jing;MIN Qiru;AN Derong;WEN Junming;YANG Zhao;WANG Yang(College of Plant Protection,Northwest A&F University,Yangling Shaanxi 712100,China;Xianyang Branch,Shaanxi Tobacco Corporation,Xianyang Shaanxi 712000,China)
出处
《西北农业学报》
CAS
CSCD
北大核心
2023年第8期1268-1278,共11页
Acta Agriculturae Boreali-occidentalis Sinica
基金
陕西省烟草公司咸阳市公司科技项目([2021]46号)。
关键词
烟草赤星病
多粘类芽孢杆菌
抑菌机理
生物防治
Tobacco brown spot
Paenibacillus polymyxa
Antifungal mechanism
Biological control
