Phyto Beneficial Properties Of Some Endophytic Bacteria Isolate From Of Thorn Apple (Datura Stramonium) From Adama, Oromia Regional State Of Ethiopia

Abstract

The global demand for sustainable agriculture has spurred interest in endophytic bacteria as biofertilizers and biocontrol agents. Datura stramonium, a medicinal plant abundant in Ethiopia, harbors diverse endophytes with potential Phyto-beneficial properties, yet their characterization remains limited. This study aims to screen and characterize endophytic bacterial isolates from the internal parts of Datura stramonium for their growth-promoting and biocontrol traits. Endophytic bacteria were isolated from surface-sterilized Datura stramonium tissues collected in Adama, Ethiopia. Isolates underwent morphological, microscopic, and biochemical characterization. Beneficial traits were screened via phosphate and zinc solubilization and antagonistic activity against test pathogens. Protein profiles were analyzed using MALDI-TOF, and selected isolates were identified by 16S rRNA sequencing. Growth responses to temperature, pH, salt concentration, carbon, and nitrogen sources were evaluated. Secondary metabolites were extracted using ethyl acetate, analyzed by GC-MS and TLC, and tested for antimicrobial activity. Isolates included Pseudomonas otitidis, Enterococcus faecium, Enterococcus faecalis, Klebsiella oxytoca, Bacillus cereus, Pseudomonas aeruginosa, Enterobacter hormaechei, and Paenibacillus thiaminolyticus, identified via protein profiles and sequencing. Enterococcus sp. EBIRDS 8, isolated from roots with 98.0% similarity to Enterococcus faecalis, was the most frequent and exhibited optimal growth under specific carbon, nitrogen, temperature, pH, and salt conditions. This isolate solubilized phosphate and zinc and produced secondary metabolites with inhibitory effects against pathogens, suggesting its dual role in growth promotion and biocontrol. Ethyl acetate extracts from other isolates also showed antimicrobial activity, though efficacy varied. Endophytic bacteria from Datura stramonium, particularly Enterococcus sp. EBIRDS-8, demonstrate significant plant growth-promoting and pathogen-suppressing capabilities, driven by their ability to solubilize nutrients and produce bioactive metabolites. These findings highlight their potential as sustainable agricultural tools. Field trials should validate the efficacy of Enterococcus sp. EBIRDS-8 and other isolates under natural conditions. Molecular studies and optimization of metabolite production could enhance their application, while agricultural policies in Ethiopia should support the integration of such biofertilizers to reduce chemical inputs.