Isolation and characterization of endophytic bacteria from Pennisetum purpureum Schumach

Abstract

Pennisetum purpureum Schumach, commonly called elephant grass, found in tropical and subtropical climates is used as an energy crop as well as a forage grass. As part of an ongoing exploration of environmentally friendly agricultural approaches in Vietnam, which includes the utilization of endophytic species and endogenous bacteria in fertilizer synthesis, studies were conducted on elephant grass. Elephant grass specimens were gathered and examined to investigate the advantages of endogenous bacteria during elephant grass growth. Endogenous bacteria capable of generating IAA were identified from Pennisetum purpureum Schumach samples collected in the provinces of Hai Duong, Cao Bang, and Thai Nguyen. Five of these strains were chosen for their capacity to stimulate plant development and fight harmful bacteria. All selected strains were gram-negative and motile endophytic bacteria. After 72 hours in a medium with a pH of 7, 100 mg/l L-tryptophan, and 30°C on liquid NA media, the study identified five endogenous bacterial strains (HDR5, HDR9, TNT3, CBR1, and CBR2) that produced the maximum amounts of IAA. HDR5 and CBR2 strains demonstrated the ability to inhibit plant-pathogenic Xanthomonas strains. The investigation of HDR5’s 16S rRNA nucleotide sequence revealed that it is closely linked to the genus Enterobacter. The study suggests the use of endogenous bacteria in fertilizer synthesis as an effective and eco-friendly approach.