摘要
前期研究中已证实紫云英根瘤菌 ( Rhizobium astragalus) JS5 A1 6菌株对水稻生长有一定的促生作用 ,利用 gus A基因标记的 JS5 A1 6菌株 (编号为 JS5 A1 6G)接种水稻种子并检测其在水稻 (汕优 63)生长初期的根圈定殖动态及分布。结果表明菌株 JS5 A1 6G在水稻出苗后 2 d根圈定殖密度大量增加 ,第 4天达到最大值 1 6d后趋于稳定。将水稻根表面灭菌后 ,检测菌株 JS5 A1 6G在根内的定殖情况 ,发现在“汕优 63”出苗后 2 d检测不出菌株 JS5 A1 6G,第 4天可检测出。根部直接染色显示 ,菌株 JS5 A1 6G在根部的分布并不均匀 ,主要是在根系的某些部位形成微菌落。同时利用 lux AB发光酶基因标记紫云英根瘤菌 JS5 A1 6菌株(编号为 JS5 A1 6L)研究其在不同品种水稻根部的定殖动态。结果表明 ,菌株 JS5 A6L在不同水稻品种“汕优63”、“汕优 64”和“马协 1 1 8- 2”根部的定殖密度不同且可以进入不同水稻品种的根内。在整个水稻生长期内菌株 JS5 A1 6L在“汕优 64”根部的定殖密度明显高于其在“汕优 63”根部的定殖密度 ,在“马协 1 1 8- 2”的定殖密度与其在“汕优 63”、“汕优 64”根部相比没有显著差异。但菌株 JS5 A1 6L在不同水稻根部的定殖动态相似 ,数量均在水稻生长到 60～ 75 d时 (即水稻的孕穗期 )
Root colonization of rice by Rhizobium astragalus JS5A16 marked with gusA and luxAB genes respectively was monitored. The strain has been proved to be a rice-growth promoting bacterium. In the experiment with Jensen sterile ni trogen-free medium, the gusA gene marked strain JS5A16G could successfully colonize the rhizosphere of rice. It multiplied rapidly after sprouted for 2～4 days, the highest colonization density was reached on 4th day, then its populati on began to decrease and trended to be stable. Strain JS5A16G was also found in endorhizosphere after 4th day of spoution. The localization of strain JS5A16G wa s visualized with steromicroscopy and x-GlucA staining of rice root. It formed microclonnies and which distributed on the root unevenly. The colonization density of luxAB genes marked strain JS5A16L in rhizosphere of three different rice cultivars “Shan You 63”, “Shan You 64”, “Ma Xie 11 8-2” was different in sterile pot soil experiments, however, it entried into t he inner of rice root. All of the colonization density reached the maximum after strain JS5A16L coated seeds sown for 60～75 days. The colonization density of J S5A16L in the root of “Shan You 64” was significantly higher than that in “S h an You 63”. Strain JS5A16L could get into the endorhizosphere of different rice cultivars.the inne
出处
《生态学报》
CAS
CSCD
北大核心
2003年第4期771-776,共6页
Acta Ecologica Sinica
基金
国家自然科学基金资助项目 ( 39970 0 2 7)~~
