Aim: Tea (Camellia sinensis (L.) O. Kuntze) is an economically important caffeine-containing beverage crop with massive plantation in the Northeast corner of the agroclimatic belt of India. The main aim of the work was to isolate, identify and characterize the native plant growth promoting endophytes associated with tea for future microbe based bioformulation. Methods and Results: A total of 129 endophytic bacteria were isolated and characterized for plant growth promoting traits such as indole-3-acetic acid (IAA), phosphate solubilization, ammonia production, biocontrol traits like siderophore and extracellular enzyme production. BOX-PCR fingerprinting was used to differentiate the various bacterial isolates obtained from six different tea species. 16S rRNA sequencing and BLAST analysis showed that these isolates belonged to different genera, that is, Bacillus, Brevibacterium, Paenibacillus and Lysinibacillus. Lysinibacillus sp. S24 showed the highest phosphate solubilization and IAA acid production efficiency of 268Á4 AE 14Á3 and 13Á5 AE 0Á5 µg ml À1 , respectively. Brevibacterium sp. S91 showed the highest ammonia production of 6Á2 AE 0Á5 µmol ml À1 . Chitinase, cellulase, protease and pectinase activities were shown by 4Á6, 34Á1, 27Á13 and 13Á14% of the total isolates, respectively. Similarly, 41% of the total isolates were positive for 1-aminocyclopropane-1carboxylic acid (ACC) deaminase activity. Further, the potent PGP isolates, S24 and S91 were able to enhance the vegetative parameters such as dry/fresh weight of root and shoot of tea plants in nursery conditions. Conclusion: Our findings corroborate that tea endophytic bacteria possess the potential to demonstrate multiple PGP traits both, in vivo and in vitro and have the potential for further large-scale trials. Significance and Impact of the Study: The exploration of tea endophytic bacterial community is suitable for the development of bioformulations for an integrated nutrient management and thus sustainable crop production and decreasing the hazardous effects of chemical fertilizers on the environment and human health.

Novel antibiotic breakthroughs are urgently required to combat antimicrobial resistance. Actinomycetia are the principal producers of antibiotics.

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