Endophytes are the hidden companions of inner plant tissues with the ability to undergo various plant growth mechanisms to benefit their host. Looking at the endophytic microbes benefits, a total of 67 putative endophytic bacteria were isolated using different nutrient growth media from three diverse maize genotypes grown at Baru Sahib the Valley of Divine Peace Himachal Pradesh. Out of the 67, 10 endophytic bacterial isolates were selected for further characterization on the basis of plant growth-promoting (PGP) attributes. Phosphorus (P) and potassium (K) solubilization was observed in about 25% of the bacterial isolates. Additionally, bacterial endophytes ability to undergo mechanisms like nitrogenase activity, production of indole acetic acids, and siderophores was also studied. Among the 10 selected bacterial strains, three efficient endophytic PGP strains EU-A2SK1, EU-M4ARAct, and EU-E1RT3-1 were identified as Pseudomonas brenneri, Ewingella americana, and Pantoea agglomerans, respectively. The phylogenetic tree was constructed to know the taxonomical affiliations of selected bacterial strains. These three efficient endophytic bacterial strains were tested on the maize seeds. The isolates efficiently increased the shoot length and enhanced anthocyanin, chlorophyll content, physiological available iron, and total protein content when compared to untreated control maize plants at 60 days of maize plant growth. These bacterial strains, as single or in a consortium, could be useful as bioinoculants for sustainable agriculture.
Key words: Biochemical levels, Endophytes, Maize, Pantoea, Plant growth promotion, Sustainable Agriculture