Biological Control of Fusarium Wilt of Tomato – A Review
Fusarium wilt of tomato (Lycopersicum esculentum) caused by Fusarium oxysporum f.sp. lycopersici leads to high losses of tomatoes in many countries. Increasing restraints on the use of pesticides encourages adoption of use of alternative strategies of controlling the disease. Alternative strategies include use of biocontrol agents. Bacterial biocontrol agents with promising biocontrol activities against F. 0xysporum f. sp. lycopersici include Pseudomonas flourescens, P. putida, P. chlororaphis, P. alcaligenes, Bacillus subtilis, Streptomyces pulcher, S. canascens, S. citreoflourescens, S. corchorusii and S. mutabilis. Fungal biocontrol agents that are efficacious against F. oxysporum f.sp. lycopersici include Penicillium oxalicum, P. purpurogenum, Trichoderma harzianum, T. piluliferum, Pythium oligandrum, non-pathogenic Fusarium oxysporum Fo47 and Trametes versicolor. Biological control agents including bacteria and fungi have shown some promise for the control of Fusarium wilt of tomato. This paper discusses the mode of action of non-pathogenic strains of F. oxysporum, other fungi and bacteria including fluorescent pseudomonads in the management of Fusarium wilt of tomato. The relative importance of systemic induced resistance in the suppression of Fusarium wilt is discussed.