Identification of endophytic bacteria isolated in talahib (Saccharium spontaneum L.) (sic) roots

Endophytic bacteria are endosymbiotic microorganisms prevalent among plants that colonize its intracellular spaces and do not cause plant disease or significant morphological changes. Wild grasses such as talahib (Saccharium spontaneum L.) are under explored as source of growth promoting endophytic bacteria for commercial application to crops. The beneficial endophytic bacteria isolated in talahib roots were in-vitro screened for its plant growth promoting activities and the promising isolates were identified using Biolog OmniLog Identification System. The Burk's medium, a nitrogen-free medium was used in isolating the potential endophytes. A total of 19 isolates from talahib roots obtained from Science City of Muñoz and San Jose City, Nueva Ecija [Philippines]were tested for the production of growth-promoting compounds. These compounds include indoleacetic acid (IAA) production, phosphate solubilization and starch hydrolysis. Out of 19 isolates, four produced IAA in culture. One of the most important mechanisms involved in plant-growth promotion is the bacterial excretion of phytohormones, such as IAA. Nine isolates showed positive in phosphorus stabilization by the formation of clearing zone around the isolates grown in Pikovskaya's medium. Among the 19 isolates evaluated, two possessed the capability to utilize stach. Three out of 19 isolates were selected based on their performance on the in-vitro screening. In this paper, two endophytic bacteria namely, Burkholderia plantarii and Acinetobacter baumanni were biochemically identified. These endophytes associated with talahib roots produced growth-promoting compounds that may stimulate plant growth. Present findings conclude that talahib roots can be a good source for isolating beneficial microbes. However, several in-vitro assay tests and evaluation of the selected isolates under screen house conditions is highly recommended to further determine its efficacy as plant-growth enhancer.