水稻内生放线菌类群及其对宿主病原菌的抗性研究  

Studies on Communities of Endophytic Actinomycetes from Rice and Their Antipathogenic Activities In vitro

作　　者：田新莉[1] 曹理想[1] 杨国武[1] 黄炳超[2] 周世宁[1] 陈明[1] 肖汉翔[2] 

机构地区：[1]广州中山大学生命科学学院生物防治国家重点实验室,广州510275 [2]广东省农业科学院植物保护研究所,广州510275

出　　处：《微生物学报》2004年第5期641-646,共6页Acta Microbiologica Sinica

基　　金：国家自然科学基金 ( 3 0 3 70 0 3 0 );广东省自然科学基金 ( 0 1112 4)~~

摘　　要：采用常规方法对广东省番禺和五山两地种植的水稻内生放线菌进行分离、鉴定和分析 ,结果表明水稻内生放线菌多属于链霉菌属 (Streptomyces) ,其中灰褐类群链霉菌 (S .griseofuscus)的分离频率最高为 36 1%～ 6 9% ,是水稻植株中的优势内生放线菌类群。研究了内生放线菌在水稻植株各器官中的分布 ,结果表明根中内生放线菌的多样性高于茎叶。番禺地区种植的水稻中分离出的内生放线菌种类较多。从感病品种及生长不良水稻植株中分离出的内生放线菌种类比较丰富。通过回接分离试验及利用扫描电镜观察内生菌在植物体内分布发现 ,水稻优势内生放线菌回接无菌组培苗后 ,不仅能够定殖在水稻植株的根表和根内部 ,而且存在于茎杆和叶片中。通过平板颉抗及代谢物的活性测定试验 ,发现所分离的内生放线菌 5 0 %对水稻某些病原菌有颉抗活性 ,其中灰褐类群链霉菌的比例达到 5 5 4 % ,成为所分离的水稻内生放线菌类群中具有颉抗活性的最大群体。This is the first report of filamentous actinobacteria isolated from surface-sterilized root and leave tissues of healthy rice plants. The isolation, characterization and analysis of the populations of endophytic actinomycetes were carried out on four rice cultivars in Panyu district and Wushan district in Guangdong province, South China. For all the different rice cultivars from the two sites, most endophytic actinomycetes is Streptomyces, among which Streptomycetes griseofuscus constitute the preponderant actinomycetes accounting for 36.1% to 69%. The distributions of endophytic actinomycetes in roots and leaves were different, some were organ-specific. More diverse endophytic actinomycetes were isolated from roots than from leaves. The diversity of the endophytic actinomycetes in Wushan was less than that in Panyu. The alkaline soil in Panyu is better for the growth and colonization of actionmycetes. The results suggested that differences in chemical composition of soil could influence the endophytic microbial communities of rice plants. More diverse endophytic actinomycetes were isolated from poor-growing seedlings and susceptible rice cultivars than from the disease-resistant counterparts. Endophytic actinomycetes have been successfully re-isolated after rice seedings inoculation. Streptomyces griseofuscus could not only colonize on interior and exterior of the rice roots but on the stem and leaves as observed with scanning electron microscopy. In the dual culture and activities detection of the metabolites, 50% of all the isolated endophytic actinomycetes showed antagonistic to rice pathogens. Streptomyces griseofuscus, the greatest part of all the antagonistic communities, reached 55.4% of all the active actinomycetes. These active endophytes inside the plants have intimate correlation with their host, they may play an important role in the development,physiology and defense-response of rice.

关 键 词：水稻 内生放线菌 体内定殖 颉抗活性 

分 类 号：S435.11[农业科学—农业昆虫与害虫防治]