壳寡糖联合丛枝菌根真菌对烟草根结线虫病的防治评价OA

Tobacco root knot nematode disease caused by tobacco root-knot nematode(RKN)has a widespread and difficult to control,which restricts the cultivation and production of tobacco.To explore the mechanism of co-application of AMF and chitooligosaccharide in improving tobacco resistance to RKN,this study researched the changes in tobacco agronomic traits,root vigor,and key enzyme activity,microbial community composition of rhizospheric soil after inoculation of RKN 40 days which under the effects of chitooligosaccharide and AMF.Meanwhile,the resistance index of tobacco to RKN and prevention rate were analyzed statistically.Results showed that the co-appli-cation of AMF and chitooligosaccharide effectively reduced the number of RKN,egg number,reproduction index,and root knot index,the reproductive index and the root knot index,which decreased by 44.5％,87.8％,89.3％and 79.5％respectively compared with the control group,which significantly increased the root vigor of tobacco.In addition,the co-application of AMF and chitooligosaccharide also incre-ased soil enzyme activity and the abundance of beneficial microorganisms in rhizosphere soil,compared with control group,the activities of soil dehydrogenase,sucrase,cellulase and polyphenol oxidase were increased to 118.41％,41.62％,44.06％and 31.86％,also can increase the contents of nicotine,total sugar and potassiumby 11.4％,17.5％and 24.0％,respectively,further improved the effective resistance of to-bacco to RKN.The results indicated that chitooligosaccharide and AMF could significantly reduce the incidence of RKN and improve the qual-ity of tobacco leaves,and provided a theoretical basis and solution for alleviating the damage of root-knot nematode to tobacco growth.