Induction of Plant Growth Promotion in Camellia sinensis by Bacillus megaterium and its Bioformulations

Plant growth promoting ability of Bacillus megaterium (TRS-4), isolated from rhizosphere of tea bushes, was tested on 5 varieties of teaTV-18, TV-23, TV-25, TV-26 and T-17/1/154 in the experimental field and in potted condition. An increase in height, emergence of new leaves, branches and increase in leaf numbers as well as increase in leaf dry mass was observed following application of the bacterium. The experimental field was designed in randomized block design where three replicate plots with 10 plants /treatment for each variety was taken. In the field, the experimental plot of Tea Estate was arranged into 2-replicated randomized block design, with each treatment of variety T-17/1/154 having 100 bushes. Increase in number of leaves and number of branches were significant after 12 months of application in field but in potted plants, significant increase were obtained even after 2 months of application. Significant increase in accumulation of phenolics was also observed in tea plants. B. megaterium solubilized phosphate in vitro and in vivo. Following application of the bacterium, soil P content decreased, root and leaf phosphate increased and soil phosphatase activities were enhanced. Chlorophyll contents of leaves were enhanced by the application of B. megaterium. Bioformulations of the bacterium in saw dust, rice husk and tea waste were found to survive for more than 9 months in vitro with populations in the range of 1×10 c.f.u/ml. The bioformulations were as effective as aqueous suspensions in 6-7 plant growth promotion. There was no significant difference among the aqueous suspension or different bioformulations in increase in height and number of leaves after 2 months of application, indicating that the application of bioformulations could also effectively promote tea plant growth.