猕猴桃细菌性溃疡病生防菌的筛选、鉴定及其防效初探

从健康猕猴桃植株中筛选具有生防潜力的内生放线菌,为猕猴桃细菌性溃疡病防治提供材料。采用平板渗透法筛选对猕猴桃细菌性溃疡病具有拮抗作用的内生放线菌,通过测定不同拮抗内生放线菌发酵液对猕猴桃溃疡病病原菌(Pseudomonas syringae pv.Actinidiae,Psa)的最低抑制浓度(Minimal Inhibitory Concentrations,MIC)筛选高抗性菌株;采用喷雾法及注干法进行高抗性菌株的田间防治试验;结合形态、生理生化特征及16S r DNA序列分析,明确高抗性菌株分类地位。从431株内生放线菌中筛选出7株具有明显抗性的菌株,其中菌株M109的抑菌效果最强(MIC值为0.91 mg/m L)。田间试验表明,菌株M109的喷雾法防效为72.1%,注干法防效为84.6%。分类鉴定结果显示菌株M109为肉桂地链霉菌(Streptomyces cinnamonensis)。试验表明,肉桂地链霉菌S.cinnamonensis M109对猕猴桃细菌性溃疡病防效显著,具有应用潜力。

Screening, Identification and Controlling Effects of Biocontrol Strain against Chinese Gooseberry or Kiwi Fruit Bacterial Canker

Endophytic actinomycetes (EA) having biocontrol potential inhibition against Chinese gooseberry (Actinidia chinensis)(CGB) or kiwi fruit bacterial canker were screened from healthy native plants of CGB to provide material to control the disease adopting plate osmotic method. Different minimal inhibitory concentration (MIC) of fermented broth of EA against CGB canker pathogen Pseudomonas syringae pv. Actinidiae (Psa) was tested to screen high resisting strain (HRS), and adopt spraying method and trunk injection method to carry out field experiment for the HRS; combined with morphology, physiological and biochemical and 16S rDNA sequencing analysis to confirm the taxonomical location of the HRS. From a total of 431 EA strains were isolated from the native plants of CGB seven strains were screened that had obvious resistance against the pathogen. Among them strain M109 exhibited the strongest inhibition activities against Psa with MIC value at 0.91 mg/mL. Field experiments showed that the controlling efficiency with spraying method was at 72.1% and 84.6% with trunk injection method. The strain M109 was identified as Streptomyces cinnamonensis. The experiments showed that S. cinnamonensis strain M109 against CGB canker had a significant controlling efficiency and possessed application potential.