Abstract The goal of this study was to evaluate the role of seed inhabiting bacterial endophytes on finger millet seedling development and protection from fungal infection. This study has shown that removal of endophytic bacteria from millet seeds compromised seedling health, however, re-inoculation of the same bacterial isolates restored its growth. A total of six endophytic bacteria were isolated from surface-sterilized seeds of finger millet and molecularly identified by 16S rDNA sequencing as Paenibacillus dendritiformis (EC1), Enterobacter hormaechei (EC2), Enterobacter cloacae (EC3), Bacillus safensis (EC4), Enterobacter hormaechei (EC5), and Enterobacter hormaechei (EC6). These isolated endophytes were tested for their plant growth-promoting activities. Enterobacter strains (EC2, EC3, EC5 and EC6) were found positive for IAA (Indole acetic acid) test and showed phosphate as well as potassium solubilization activities while siderophore production was shown by EC1 and EC4. Antifungal activity was also evaluated with isolate EC1 showing inhibition against all the tested phytopathogens. In seedling protection assay, bacterial endophytes significantly reduced the infection from Fusarium oxysporum. Re-inoculation experiment was carried out and it was found that bacterial strains EC1, EC4, and EC5 were most active in seedling development of finger millet, showing considerable improvement in root-shoot lengths, fresh weights and content of chlorophyll pigments. Endophytic bacterial colonization in the seedling roots was observed using fluorescent microscopy. This study reports the presence of endophytic bacteria inside seeds of finger millet having stimulatory effects on its growth and development.

中文翻译：

---

寄居于指黍（Eleusine coracana L.）内生菌的种子促进幼苗生长发育，防止真菌病害

摘要 本研究的目的是评估种子内生细菌对指黍幼苗发育和防止真菌感染的作用。这项研究表明，从小米种子中去除内生细菌会损害幼苗的健康，但是，重新接种相同的细菌分离物会恢复其生长。从表面灭菌的小米种子中分离出6种内生细菌，并通过16S rDNA测序分子鉴定为树突状芽孢杆菌（EC1）、霍马氏肠杆菌（EC2）、阴沟肠杆菌（EC3）、安全芽孢杆菌（EC4）、霍马氏肠杆菌(EC5) 和霍马氏肠杆菌 (EC6)。测试这些分离的内生菌的植物生长促进活性。肠杆菌菌株（EC2、EC3、EC5 和 EC6) 对 IAA（吲哚乙酸）试验呈阳性，并显示出磷酸盐和钾的溶解活性，而 EC1 和 EC4 显示出铁载体的产生。还用分离物 EC1 评估了抗真菌活性，显示对所有测试的植物病原体有抑制作用。在幼苗保护试验中，细菌内生菌显着降低了尖孢镰刀菌的感染。再接种试验发现，菌株EC1、EC4和EC5在指黍幼苗发育中最为活跃，在根茎长度、鲜重和叶绿素色素含量等方面均有显着改善。使用荧光显微镜观察幼苗根中的内生细菌定植。