不同茬口土壤和大豆品种对根瘤菌遗传多样性的影响  

Effects of crop rotation and soybean cultivar on rhizobial genomic diversity in root nodules

作　　者：王浩[1] 赵双进[2] 王绍东[1] 陈文新[3] 

机构地区：[1]东北农业大学国家大豆工程技术研究中心,哈尔滨150028 [2]河北省农林科学院粮油作物研究所,石家庄050031 [3]中国农业大学生物学院,北京100094

出　　处：《中国生态农业学报》2014年第6期648-654,共7页Chinese Journal of Eco-Agriculture

基　　金：哈尔滨市科技局青年科技创新人才项目(2013RFQQJ173);黑龙江省青年科学基金项目(QC2013C013);“十二五”农村领域国家科技计划课题(2011BAD35B06-1-3);东北农业大学大豆生物学教育部重点实验室开放基金项目(SB12B03)资助

摘　　要：土壤和大豆品种是影响根瘤菌遗传多样性的主要因素。本研究通过土壤捕捉试验,分别从冬小麦茬口和玉米茬口土壤中种植的4个大豆品种根瘤中分离得到149株快生根瘤菌和49株慢生根瘤菌。对这些菌株进行16S rDNA限制性酶切分析(ARDRA)、16S-23S基因间隔(IGS)以及共生基因(nod C)的限制性片段长度多态性分析(RFLP),考察土壤茬口和大豆品种对大豆根瘤菌遗传多样性的影响。ARDRA分析结果表明,快生根瘤菌全部属于中华根瘤菌属(Sinorhizobium),慢生根瘤菌全部属于慢生根瘤菌属(Bradyrhizobium)。IGS酶切分型将所有菌株分为3种图谱类型,其中型Ⅰ与辽宁慢生根瘤菌(B.liaoningense)的模式菌株酶切图谱类型完全一致,型Ⅱ和型Ⅲ与费氏中华根瘤菌(S.fredii)的模式菌株酶切图谱类型完全一致。综合以上结果,本研究分离到的菌株分属于以上2个种。在两种茬口土壤中快生根瘤菌费氏中华根瘤菌均为优势种群,在冬小麦茬口土壤中的比例(平均95.18%)远高于玉米茬口土壤(平均53.78%)。‘冀豆12’大豆品种的费氏中华根瘤菌在两种茬口土壤中所占比重均高于其他品种。对菌株的IGS基因型与宿主大豆品种的相关性分析表明,大豆品种与根瘤菌IGS基因型之间具有一定相关性。nod C-RFLP酶切分型结果表明,土壤茬口和大豆品种对菌株的共生基因无明显影响。本研究表明根瘤菌、土壤茬口和大豆品种间存在一定的相关性。土壤茬口对根瘤菌的种群结构影响较大,大豆品种对根瘤菌的基因型具有一定的选择性。Soil and soybean cultivar are the main factors that influence genetic diversity of rhizobia.In this study,we isolated a total of 149 fast-growing and 49 slow-growing nodule bacteria strains from four soybean cultivars grown in soils with two different crop rotations by plant trapping method.We used amplified 16S rDNA restriction analysis（ARDRA）,restriction fragment length polymorphism（RFLP） analysis of 16S-23S intergenic spacer（IGS） gene and nod C gene to investigate the effects of crop rotation and soybean cultivar on genomic diversity of rhizobia.ARDRA showed two rDNA types.Type Ⅰ covered all fast-growing strains belonged to Sinorhizobium,while type Ⅱ contained all slow-growing strains belonged to Bradyrhizobium.Three patterns constituted IGS-RFLP—IGS pattern Ⅰ identical to B.liaoningense of slow-growing strains,IGS pattern Ⅱ and IGS pattern Ⅲ similar to two reference strains of S.fredii of fast-growing strains.Based on the results for 16S-23S IGS ARDRA and RFLP,slow-growing strains were identified as B.liaoningense and fast-growing strains identified as S.fredii.Percent average of S.fredii in soils with winter wheat as fore-rotating crop（95.18%） was much higher than that in soils with maize as fore-rotating crop（53.78%）,and this varied in relation to different soybean cultivars.In both soil types,‘Jidou 12’ showed the highest affinity for S.fredii.Correlation analysis between IGS genotypes of 198 strains and host soybean cultivars showed that ‘Wuxing 1’ cultivar was most correlated to IGS type Ⅰ（Bradyrhizobium）,‘Williams’ and ‘Jidou 17’ cultivars most correlated to IGS type Ⅱ（Sinorhizobium） and ‘Jidou 12’ cultivar most correlated to IGS type Ⅲ（Sinorhizobium）.Results for C-RFLP node showed that crop rotation and soybean cultivar did not affect the nodulation genotype of strains.The results from this study revealed some interactions among rhizobia,crop rotation and soybean cultivar.The effect of crop rotation on rhizobium species was greater t

关 键 词：前茬作物 土壤 大豆品种 根瘤菌 遗传多样性 

分 类 号：Q938[生物学—微生物学]