新疆加工番茄溃疡病的发生及其病原菌研究

[目的]番茄溃疡病是番茄上最严重、最具毁灭性的病害之一,2010年6～8月在新疆石河子、奎屯等地的加工番茄田问相继发现典型症状的病株和病果.旨在明确引起该病害的主要病原菌种类,为进一步的防治研究打好基础.[方法]对采集的病株、病果进行病原菌的分离纯化,应用注射法、剪叶法及喷雾接种测定菌株的致病性;通过供试菌株的形态学特征、培养特性、生理生化反应的测定、16S rDNA序列分析及番茄溃疡病菌特异性引物的PCR检测确定病原的归属.[结果]所有供试菌株对供试番茄都具有致病性,表现为茎秆爆裂,植株萎蔫死亡.菌株形态特征、培养特性及生理生化反应都与密执安棒形杆菌密执安亚种(Clavibactermichiganense subsp.michiganense)的特征相一致;供试菌株16S rDNA核苷酸序列与德国已报道的密执安棒形杆菌密执安亚种菌株的核苷酸序列同源性为99.86;;特异性引物检测也得到预期目标片段.[结论]因此,将此病害确定为番茄溃疡病,其病原为密执安棒形杆菌密执安亚种(C.michiganensis subsp.Michiganensis).

Occurrence and Identification of Bacterial Canker of Processing Tomatoes in Xinjiang

【Objective】 Tomato bacterial canker is one of the most severe and crushing diseases to tomatoes.Infested tomato plants were observed in succession,in Shihezi and Kuitunn of Xinjiang during June-August 2010.The objective of this study was to determine the pathogens,and this would contribute to controlling disease.【Method】Pathogenicity of isolates were measured by using inject-,clip-,spray-inoculating.The strains were identified based on morphological,cultural,physiological and biochemical characteristics and the analysis of the 16S rDNA genes sequences and PCR amplified fragments by using Clavibacter michiganense subsp.michiganense species-specific primers.【Result】All inoculated tomatoes appeared stems split,wilting or dying.The strain's morphological,cultural and physiological,biochemical characteristics were consistent with Clavibacter michiga-nense subsp.michiganense's;and the homology of 16S rDNA nucleotide sequences with German's reported strain was 99.86%;PCR species-specific primers detection also obtained expected targets.【Conclusion】Therefore,this disease was named tomato bacterial canker and its pathogen was C.michiganensis subsp.Michiganensis.