Soil Science & Engineering Department, Faculty of Agriculture, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
Production Engineering & Plant Genetics Department, Faculty of Agriculture, Shahid Chamran University of Ahvaz, Ahvaz, Iran.
Arch Microbiol. 2021 Mar;203(2):513-521. doi: 10.1007/s00203-020-02038-z. Epub 2020 Sep 23.
This study was performed to isolate non-rhizobial endophytic bacteria from the root nodules of Glycine max (soybean), Vigna radiata (mung bean) and Vigna unguiculata (cowpea). The bacteria were characterized for plant growth promoting properties such as indole acetic acid production, phosphate and zinc solubilisation, nitrogen fixation and hydrogen cyanide production. Phylogenetic identification was performed using the Neighbour-Joining method on16S rRNA gene sequences. The impact of salt tolerant isolates on some properties of wheat cv. Chamran was evaluated by a completely randomised factorial design. Nine isolates having some characteristics related to plant growth promotion were identified as Staphylococcus hominis 7E, Streptomyces sp. 11E, Bacillus sp. 13E, Acinetobacter sp. 19E, from mung bean, Bacillus endophyticus 1E from cowpea, Staphylococcus hominis 9E, Bacillus endophyticus 14E, Brevundimonas sp. 16E and Kocuria sp. 26E from soybean nodules. Isolates 7E and 19E caused maximum growth inhibition of Fusarium on PDA plate. All isolates were able to grow at salinity levels of mixtures containing up to 400 mM of NaCl, CaCl and MgCl, but their growth was inhibited by increasing salinity level. Only the growth of isolate 14E increased at three levels of salinity compared with control. Some isolates, i.e. 7E, 14E, 19E and 26E had higher colony diameter at 45 °C after 48 h of incubation compared to the growth at 30 and 40 °C. Inoculation of soil with isolate 1E and isolate 26E caused to ameliorate salinity stress in wheat and increased the weight of 1000-grains as compared with non-inoculated treatments.
本研究从大豆（黄豆）、绿豆（绿豆）和豇豆（豇豆）的根瘤中分离出非根瘤内生细菌。对细菌进行了植物促生长特性的特征描述，如吲哚乙酸的产生、磷酸盐和锌的溶解、固氮和氢氰酸的产生。基于 16S rRNA 基因序列，使用邻接法进行了系统发育鉴定。采用完全随机因子设计，评估了耐盐分离物对小麦品种 Chamran 某些特性的影响。从绿豆中鉴定出 9 个具有与植物生长促进相关特性的分离物，分别为 Staphylococcus hominis 7E、Streptomyces sp. 11E、Bacillus sp. 13E、Acinetobacter sp. 19E，从豇豆中分离出 Bacillus endophyticus 1E，从黄豆中分离出 Staphylococcus hominis 9E、Bacillus endophyticus 14E、Brevundimonas sp. 16E 和 Kocuria sp. 26E。分离物 7E 和 19E 在 PDA 平板上对镰刀菌的生长抑制作用最大。所有分离物都能在含有高达 400 mM NaCl、CaCl 和 MgCl 的混合物盐度下生长，但随着盐度的增加，它们的生长受到抑制。只有分离物 14E 的生长在三个盐度水平下与对照相比有所增加。与 30 和 40°C 的生长相比，一些分离物，如 7E、14E、19E 和 26E，在 45°C 下孵育 48 小时后，菌落直径更高。与未接种处理相比，接种分离物 1E 和分离物 26E 可改善小麦的盐胁迫并增加千粒重。
