Biochemical characterization of multifunctional endophytic fungi from Bambusa oldhamii Munro

Abstract

In a plant-endophyte relationship, substances secreted by microorganisms can help the plant to defend itself against pathogens and also to promote an increase in biomass. This study aimed to biochemically characterize endophytic fungi from Bambusa oldhamii Munro, aiming at future studies on plant growth promotion, as well as on resistance induction. The following fungal isolates from B. oldhamii were used: 29 (Acrocalymma sp.); 122 (Botryobambusa fusicoccum); 711 (Phoma sp.); and 712 (Phoma sp.). Biochemical characterization was performed, analyzing the production of indole-acetic acid, chitinases and glucanases, as well as the presence or absence of polyphenol oxidases and phosphate solubilization activity in vitro. The isolate 29 produced larger amounts of indole-acetic acid and chitinases, yielding 31.55 mg mL-1 after 96 h and 2.59 U mL-1 after 120 h, respectively. The isolate 122 produced an increased amount of glucanases, yielding 2.65 U mL-1 after 72 h. The isolates 29, 711 and 712 produced polyphenol oxidases. The isolate 711 showed phosphate solubilization activity in vitro. These results indicate that the isolates under study show a potential for inducing resistance in plants and for future studies on the increase of plant biomass.

KEYWORDS: Antimicrobial activity, auxins, bambusicolous fungi, polyphenol oxidases.