抗烟草PVY生防细菌D3-1的筛选鉴定及活性物质分析

Screening,Identification and Active Substance Analysis of Biocontrol Bacterium D3-1 against Tobacco PVY

由马铃薯Y病毒(Potato virus Y,PVY)引起的病毒病在烟草种植地区大面积发生,对烟草品质和产量产生重大影响。采用半叶枯斑法筛选出对烟草PVY防治效果优良的生防细菌D3-1,对PVY的枯斑抑制率达99.71%,经形态学、生理生化特性以及16Sr DNA序列鉴定其为解淀粉芽胞杆菌Bacillus amyloliquefaciens。菌株D3-1具有广谱的抑菌能力,可抑制病原真菌和细菌生长,菌株D3-1发酵液(1×10^(9)CFU/m L)对烟草PVY的田间防治效果为63.67%。全基因组测序分析发现菌株D3-1基因组含有表面活性素surfactin、丰原素fengycin、嗜铁素bacillibactin等12种具有抑菌作用的次生代谢产物合成基因簇,经HPLC-MS定性分析确定了表面活性素surfactin和丰原素fengycin等32个脂肽类提取物。菌株D3-1对PVY有良好防治效果,具有作为防治烟草PVY生防菌剂的潜力。

Viral diseases caused by potato virus Y(PVY)occur extensively in tobacco planting areas,significantly impacting tobacco quality and yield.Through half-leaf necrosis spot method,the biocontrol bacterium D3-1 with excellent efficacy against PVY in tobacco was screened,exhibiting an inhibition rate of 99.71%.Based on morphological,physiological,biochemical characteristics and 16S rDNA sequence analysis,D3-1 was identified to be Bacillus amyloliquefaciens.D3-1 strain displayed broad-spectrum anti antimicrobial activity,inhibiting the growth of pathogenic fungi and bacteria.Field trials with D3-1 fermentation broth(1×10^(9) CFU/mL)resulted in an efficacy of 63.67%against PVY in tobacco.Whole-genome sequencing revealed that strain D3-1 harbored 12 gene clusters responsible for the synthesis of secondary metabolites,including surfactin,fengycin,and bacillibactin,known for their antimicrobial properties.Qualitative analysis using HPLC-MS confirmed the presence of 32 peptide extracts,including surfactin and fengycin.Strain D3-1 exhibited promising efficacy against PVY,demonstrating its potential as a biocontrol agent for managing PVY in tobacco.