Aims: The present study was carried out to screen the phylloplane bacteria from tea for antagonism against grey blight caused by Pestalotiopsis theae and blister bight caused by Exobasidium vexans and to further evaluate the efficient isolates for disease control potential under field condition. Methods and Results: A total of 316 morphologically different phylloplane bacteria were isolated. Among the antagonists, the isolates designated as BMO-075, BMO-111 and BMO-147 exhibited maximum inhibitory activity against both the pathogens under in vitro conditions and hence were selected for further evaluation under microplot field trial. Foliar application of 36-h-old culture of BMO-111 (1 9 10 8 colony-forming units ml À1 ) significantly reduced the blister blight disease incidence than the other isolates. The culture of BMO-111 as well as its culture filtrate effectively inhibited the mycelial growth of various fungal plant pathogens. The isolate BMO-111 was identified as Ochrobactrum anthropi based on the morphological and 16S rDNA sequence analyses.Conclusions: It could be concluded that the biocontrol agent O. anthropi BMO-111 was effective against blister blight disease of tea. Significance and Impact of the Study: Further study is required to demonstrate the mechanism of its action and formulation for the biocontrol potential against blister blight disease of tea.

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Aims: The present study was aimed to evaluate the integration of Ochrobactrum anthropi BMO-111 and chemical fungicides (copper oxychloride and hexaconazole) against blister blight disease of tea. Methods and Results: Application of the liquid culture of O. anthropi BMO-111 (36-h-old culture broth) was found to be effective in combined sprays with individual chemical fungicides (copper oxychloride and hexaconazole). Spray application of O. anthropi BMO-111 to tea bushes improved the biochemical parameters such as the levels of chlorophyll, polyphenols, and catechins in the harvestable tea shoots. Moreover, in the microplot and large scale trials, the integrated treatment of every two O. anthropi BMO-111 sprays followed by a single fungicides spray was found to be more efficient than the stand alone O. anthropi BMO-111 or chemicals sprays. Further, pathogenicity study employing Swiss albino mice showed no mortality in the test animals when challenged with O. anthropi BMO-111 through oral, intravenous and intranasal routes. Conclusions: The field trials clearly established that O. anthropi BMO-111 has capability to reduce incidence in integrated management of blister blight disease of tea and safe to use in the field. Significance and Impact of the Study: The results indicate that O. anthropi BMO-111 can be used as an agricultural input in the integrated crop protection systems.

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