Bacterial wilt of tomato in Karnataka and its management by Pseudomonas fluorescens

Abstract

Field surveys undertaken in major tomato growing districts of the Karnataka state, located in southern part of India, revealed a high incidence of bacterial wilt caused by Ralstonia solanacearum and it is one of the most destructive bacterial diseases of economically important crops. Across all the tomato cultivars under evaluation, the disease incidence in plants ranged from 9% to 39% whereas the incidence in seeds ranged from 4% to 18%. The effects of tomato seed treatments with Pseudomonas fluorescens in the control of bacterial wilt under greenhouse conditions revealed that the treatments protected plants against soil-borne infections of the bacterial wilt organism. Seed treatment with antagonistic P. fluorescens strain significantly improved the quality of seed germination and seedling vigour. The disease incidence was significantly reduced in plants raised from P. fluorescens treated seeds followed by challenge inoculation with R. solanacearum. Periodic field surveys for the incidence of bacterial wilt of tomato could be recommended to monitor the populations of the bacterial wilt pathogen. Workable measures are presented that could lead to the reduction of the prevalence of this serious disease in affected fields of the small farm-holders.

RETRACTED: <i>Induction of Systemic Resistance in Tomato against Ralstonia solanacearum by Pseudomonas fluorescens</i>

“…Many of the fluorescent pseudomonads, mainly P. fluorescens, have been isolated from suppressive soil for the management of soil borne diseases. Systemic resistance was enhanced in response to R. solanacearum challenge in tomato due to high accumulation of defense enzymes [23].…”

“…high induction of PAL and POX was observed in P. fluorescens pretreated tomato seedlings, which were inoculated with R. solanacearum [23].…”

“…The isolates were subjected to identification and confirmation based on the morphological, physiological, cultural, biochemical and pathogenicity studies [23] [24].…”

Comparative Efficiency of Biocontrol Agents in the Management of Root Borne Diseases of Coleus (Coleus forskohlii (Willd.) Briq.)

“…The fungal pathogen was identified and confirmed (Booth, 1977). The virulent bacterial pathogen R. solanacearum produce pink pigmented colonies with white fluid was identified by following the methods of Kelman (1954); Vanitha et al, (2009) and (Singh et al, 2012).…”

Expression of Defense Responses in Tomato against Vascular Wilt and Fruit Borer through Consortia of Fluorescent Pseudomonads and Entomopathogenic Fungi

“…Many of the fluorescent pseudomonads, mainly P. fluorescens, have been isolated from suppressive soil mainly for the management of soil borne diseases (Narayanan et al, 2015). Systemic resistance was enhanced in response to fungal and bacterial pathogens challenge in tomato due to high accumulation of defense enzymes (Vanitha et al, 2009). The present work was an effort to analyze the defense related enzyme activity in bacterial wilt pathogenesis of tomato.…”