作　　者： (孙文庆）; (康亚龙）; (刘建国）; (蒋桂英）;

机构地区： 石河子大学新疆兵团绿洲生态农业重点实验室,新疆石河子832003

出　　处： 《西北农业学报》 2017年第7期1099-1110,共12页

摘　　要： 通过在石河子大学农学院试验站开展加工番茄连作(种植1 a、连作3 a、5 a和7 a)定点微区试验,于花果期和成熟期采集根际土壤,利用聚合酶链-变性梯度凝胶电泳(PCR-DGGE)技术,分析不同连作年限加工番茄根际微生物结构和多样性的变化。结果表明,随着加工番茄连作年限的延长,根际土壤细菌的丰富度和Shannon-Wiener多样性均有所降低,而真菌的丰富度和多样性有所升高,且成熟期>花果期。连作对土壤细菌和真菌的Pielou均匀度指数影响不明显,说明各处理土壤微生物类群分布比较均匀。连作明显改变了土壤中土著细菌的群落结构,一些土著细菌优势种群数量减少或消失;土壤真菌的优势种群随连作年限的变化较大,某些真菌类群大量富集,而另一些真菌数量明显减少,甚至消失,其中,加工番茄连作5年时土壤中新出现的真菌优势种群最多,且与其他真菌种群的数量差异较大。加工番茄连作后土壤细菌和真菌群落结构失衡可能是产生连作障碍问题的重要因素。从条带测序结果看,各连作处理土样中细菌优势种群属于假单胞菌属(Pseudomonas sp.)、节杆菌属(Arthrobacter ramosu)、α-变形杆菌(Alpha proteobacterium)、不可培养的α-变形杆菌(Uncultured Alpha proteobacterium)和不可培养细菌(Uncultured bacterium),真菌优势种群属于不可培养真菌(Uncultured fungus)、Geosmithia putterillii、淀粉丝菌(Amylomyces rouxii)、热带念珠菌(Candida tropicalis)和漆斑菌属(Myrothecium sp)。总之,加工番茄连作导致根际有益菌数量减少而病原菌大量滋生,从而降低了加工番茄抵御病害的能力。 The objective of this experiment was to determine the effect of continuous cropping on microbial diversity in the rhizosphere of processing tomato.The field experiment,which began in 2007,was conducted at the agriculture college experiment station of Shihezi university.Processing tomato（cv.Ligeer 87-5） had been continuously cropped at the site for 1 a,3 a,5 a,and 7 a.Soil samples were collected during the first flowering and fruit stage and the mature stage.The microbial structure and community diversity in the rhizosphere soil was analyzed using PCR-DGGE methods.The results showed that the Shannon-Wiener index and the richness index of fungi in rhizosphere soil decreased as the duration of continuous cropping increased.In contrast,the Shannon-Wiener index and the richness index of bacteria both increased.Both indexes were greater during the mature stage than during the first flowering and fruit stage.Pielou＇s index was not sensitive to the duration of continuous cropping.This indicated that the evenness of the soil microbial communities was not affected by cropping duration.Soil bacterial community structure was significantly influenced by the duration of continuous cropping.Continuous cropping caused the populations of some dominant bacterial species to decrease and even disappear.The number of dominant fungal species varied significantly depending on the duration of continuous cropping.Continuous cropping significantly increased the total fungal population;however some fungal species decreased in population or disappeared.The populations of the dominant fungal species were generally greatest in plots that had been continuously cropped to tomato for 5 a.The populations of the dominant fungal species were significantly different than those of the non-dominant fungal species.The change in the population balance between bacteria and fungi may be one important reason for reduced yields in continuously cropped fields.Sequencing analysis of prominent electrophoretic bands showed that the dominant bacteria in th

关 键 词： 加工番茄 变性梯度凝胶电泳技术 根际土壤 微生物多样性 连作