【摘要】 通过16S rRNA基因和看家基因recA、atpD、rpoB的序列测定与分析,及(G+C)mol%测定等技术,对分离自河北省滦南县水稻根内的两株细菌进行分子系统发育学研究.根据系统进化树构建及其同源性分析,可确定所分离的两株水稻内生细菌属于剑菌属(Ensifer)系统发育分支;供试菌株的各保守序列与粘着剑菌(E.adhaerens)模式菌种同源性最高,除recA为97.2%外,其他均为99%～100%,可以确定供试菌属于E.adhaerens;对所分离的菌株与大豆、菜豆、三叶草、苜蓿等4种豆科植物进行结瘤试验,结果显示其中一株J3-N55可与苜蓿结瘤.野生型的E.adhaerens菌株与豆科植物结瘤的报道尚为鲜见;本文首次报道从水稻植株内分离到E.adhaerens菌株.更多还原

【Abstract】 Two Ensifer(Sinorhizobium)-like strains isolated from rice(Oryza sativa L.) roots in Luannan County,Hebei,China were investigated with a polyphasic strategy.The 16S rRNA,recA,atpD and rpoB genes were PCR amplified and sequenced,and followed by Neighbour-Joining phylogenetic analysis.The G+C content was determined by thermal denaturation method.According to the study of phylogenetics,the two strains were clustered in the genus Ensifer(Sinorhizobium),with the highest similarity to E.adhaerens ranging from 99% to 100%,except for recA gene(97.2%).To determine the nodulation ability,the nodulation tests were carried out using four different legumes: soybean(Glycine max),kidney bean(Phaseolus vulgaris),clover(Trifolium repens),and lucern(Medicago sativa).It was found that strain J3-N55 could form nodules successfully on M.sativa.To our knowledge,this is the first report about the endophytic E.adhaerens isolated from rice plant.更多还原