Biocontrol potential of phylloplane bacterium Ochrobactrum anthropi BMO-111 against blister blight disease of tea

Abstract

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.

Evaluation and entomopathogenicity of gut bacteria associated with dauer juveniles of Oscheius chongmingensis (Nematoda: Rhabditidae)

“…Some endophytic bacteria belonging to Ochrobactrum sp. have been isolated from plants, and these strains exhibit maximum antagonistic activity and possess higher chitinase and glucanase activity (Zhao, Xu, Chang, & Li, ; Zang, Zhao, Liu, & Liang, ; Sowndhararajan, Marimuthu, & Manian, ). Metabolites produced by bacterial species of Ochrobactrum inhibit the growth of a wide range of bacteria and fungi (Han, Peng, & Yi, ; Lebuhn, Achouak, Schloter, & Berge, ).…”

Integrated control of blister blight disease in tea using the biocontrol agentOchrobactrum anthropistrain BMO-111 with chemical fungicides

“…Further, the isolate effectively decreases the blister blight disease incidence under microplot field experiment (Sowndhararajan et al 2013). Based on the results of physicochemical studies and 16S rDNA analysis, the isolate BMO-111 was identified as O. anthropi and designated as O. anthropi BMO-111.…”

“…In the experimental field, O. anthropi BMO-111 was reisolated during every plucking round by using leaf washing technique (Sowndhararajan et al 2013). After the isolation, the bacterium was confirmed based on the zone of inhibition against the Pestalotiopsis theae.…”

“…Disease assessments were made during plucking rounds at 15-day-interval by picking ten samples of 50 harvestable shoots (three leaves and a bud) were randomly collected from individual plots and examined individually for the presence of lesions and expressed as percent disease incidence (Sowndhararajan et al 2013).…”

Isolation and characterization of rhizospheric Streptomyces spp. for the biocontrol of Fusarium wilt (bayoud) disease of date palm (Phoenix dactylifera L.)

“…Chemical pesticide usage is generally accepted as effective strategy, but there is lack of effective chemical product for Fusarium wilt in date palm. Apart from this there are side effects associated with chemical usage (Karlidag et al, 2007;Sowndhararajan et al, 2012;Sathiyabama and Charles, 2015). And also there are acquired resistance in pathogenic bacteria and fungi to commonly used strategies (Kumar et al, 2011).…”