Kanchalee Jetiyanon

pp. 29 - 36

Abstract

Enterobacter asburiae strain RS83 having the capacity of promoting plant growth and yield of various vegetable
crops was isolated from the rhizosphere of cassava in Phitsanulok province. The objective of this study was to investigate
possible bacterial determinants of strain RS83 involved with plant growth enhancement. Different methods such as using
specific media, biochemical tests and high performance liquid chromatography technique were used to analyze bacterial
determinants of interest relevant to plant growth promotion. Results revealed several bacterial determinants of strain RS83
implicated in plant growth improvement. These determinants released from strain RS83 included indole-3 acetic acid (IAA;
plant-hormone like), catechol siderophore enterobactin (iron-chelating agent), and gluconic acid relating to phosphate
solubilization. Moreover, the presence of pellicles in a semi-solid nitrogen-free medium inoculated with strain RS83 indicated
possible nitrogen-fixing capacity of the bacterium. In conclusion, strain RS83 possesses several bacterial determinants
involved with plant growth promotion.