Isolation, characterization and in vitro efficacy of banana phyllospheric bacteria

Phyllospheric bacteria can help in plant-growth promotion by various direct and indirect mechanisms. A total of ten healthy leaf samples were collected randomly from the banana farms located at Navsari Agricultural University, Navsari, Gujarat. A total of 28 morphologically distinct bacterial isolates were obtained in pure culture from collected samples and screened for their ability to plant growth-promoting parameters under in vitro conditions. Out of these, 14.28%, 14.28%, 28.57%, and 82.14% showed positive biological nitrogen fixation ability, phosphate solubilization, potassium mobilization, and zinc solubilization, respectively. Indole-3-acetic acid (IAA) production was detected in 28.57% of isolates and 21.42% isolates were found positive for siderophore production. All (100%) isolates showed antagonism against Fusarium oxysporum. Further, 78.57%, 39.28%, and 32.14% of isolates showed positive protease, lipase, and amylase secretion, respectively. Based on in vitro screening, the two most potent isolates with multiple plant-growth promoting (PGP) traits were identified by16S rRNA sequencing method, as Priestia megaterium and Pantoea cypripedii. Further, these isolates can be used in banana plant growth promotion as an alternative to synthetic chemicals for sustainable agriculture practices.