Biological control of wilt disease of hill banana incited by Fusarium oxysporum f.sp. cubense

Abstract

An intensive survey on incidence of wilt disease of hill banana was conducted at fourteen locations of major hill banana growing areas of Dindigul district and fourteen isolates of pathogen, Fusarium oxysporum f.sp. cubense was obtained. The mycelial growth of the isolates was observed and the virulent isolate which was collected from Adaloor village was used for further studies. Fourteen isolates of Trichoderma viride, Pseudomonas flourescens and Bacillus subtilis were isolated. The invitro efficacy of fourteen isolates Trichoderma viride, Pseudomonas flourescens and Bacillus subtilis were tested against the pathogen by dual plate technique. Among the Trichoderma viride isolates tested, Pandrimalai isolate significantly exerted highest per cent mycelial growth inhibition (72.55%) over control. The isolate from KC Patty village showed the least mycelial growth inhibition of 57.52 per cent. Among the Pseudomonas flourescens isolates tested, Perumparai isolate significantly exerted highest per cent mycelia growth inhibition of 82.64 per cent over control. The isolate from Manjalparappu village showed the least mycelial growth inhibition of 67.17 per cent. Among the Bacillus subtilis isolates tested, Poolathur isolate significantly showed highest per cent mycelial growth inhibition (59.69%) over control. The effective biocontrol agent was evaluated under in vivo condition. Among the treatments tested, the treatment viz., rhizome dipping of Pseudomonas flourescens (Perumparai isolate) @ 0.2% plus soil application of Pseudomonas flourescens (Perumparai isolate) @2.5kg talc based formulation / ha at 30, 60, 90 and 120 DAP recorded the lowest disease incidence of 10.67 per cent and showed the maximum disease reduction of 79.39 per cent over control.