【摘要】 猕猴桃溃疡病由丁香假单胞菌猕猴桃致病变种(Pseudomonas syringae pv.actinidiae,Psa)引发，是一种极具破坏力的细菌性病害，已在全球范围内造成重大经济损失。针对猕猴桃细菌性溃疡病的防治难题，本研究对分离自陕西省西安市周至县患病猕猴桃根际土壤的168株细菌进行拮抗强致病力菌株Psa M228筛选，从中得到9株具有拮抗作用的生防菌，根据16S rDNA序列构建系统发育树对生防菌进行鉴定，并采用离体叶盘真空渗透法和离体枝条有伤接种法测定生防菌防效。结果表明，生防菌RB-L-15和RB15抗菌活性显著，平均抑菌圈直径分别为29.88 mm和33.84 mm。进一步的防效测定表明，RB-L-15和RB15不仅显著降低叶盘溃疡病的病斑面积(P<0.05),下降百分率分别为90.07%和87.46%,而且显著降低枝条溃疡病的病斑长度(P<0.05),下降百分率分别为83.62%和87.79%。根据16S rDNA序列，RB-L-15鉴定为绿棕褐链霉菌(Streptomyces viridobrunneus),RB15鉴定为池生戴尔福特菌(Delftia lacustris)。更多还原

【Abstract】 Kiwifruit canker caused by Pseudomonas syringae pv.actinidiae(Psa) is a destructive bacterial disease thathas led to significant global economic losses.To address the control of kiwifruit bacterial canker,168 bacterial strains were isolated from the rhizosphere soil of infected kiwifruit plants in Zhouzhi County,Xi’an,Shaanxi Province.These strains were screened for antagonistic activity against Psa strain M228,and nine antagonistic biocontrol strains were identified.Phylogenetic trees were constructed based on 16S rDNA sequences to identify the biocontrol strains.The antibacterial activity of the biocontrol strains was evaluated using an in vitro leaf disk vacuum infiltration method and a wound inoculation method on excised branches.These methods were used to identify strains with strong inhibitory effects.The results showed that the biocontrol bacteria RB-L-15 and RB15 had significant antibacterial activity,and the average antibacterial zone diameter was 29.88 mm and 33.84 mm,respectively.Further tests showed that both RB-L-15 and RB15 significantly reduced the lesion area of leaf disc canker by 90.07% and 87.46%,respectively(P<0.05).They also decreased the lesion length of branch canker by 83.62% and 87.79 %,respectively(P<0.05).Based on the 16S rDNA sequence,RB-L-15 was identified as Streptomyces viridobrunneus,and RB15 as Del ftia lacustris.更多还原