Abstract

The grass is a common wild plant in the river delta region of the Southwest region of Vietnam. They grow abundantly and flourish in saline-acidic areas. Native grasses  interact with their endogenous microorganisms. However, there have not been many studies on this subject, especially the grass in Vietnam.

From the grass, the study isolated 3 endophytic fungi from the root. The results showed that the fungal strain with the highest P-decomposing ability was NR3 with a PO₄^3- content of 696.74 mg/L. All 3 strains were able to grow and develop, but the decomposing ability was not observed. In addition, all 3 fungal strains were able to synthesize N but the results were quite low. The ability to synthesize the plant hormone IAA in PDB medium with/without L-Tryptophan was investigated and quantified by spectrophotometry with Salkowski reagent. The results showed that in the environment without L-Tryptophan supplementation, strain NR3 had the highest IAA synthesis capacity with a total IAA content of 12.06 mg/L. In the environment with L-Tryptophan supplementation, the amount of IAA produced was higher, in which strain NR1 had an extracellular IAA content of 24.62 mg/L. The research results provided initial data on the biological capacity of endophytic fungi in the roots of reed grass, creating the premise for further studies.