Development of integrated approach to manage the fusarial wilt of banana

A detailed study (involving in vitro bioassays, greenhouse and field trials) was carried out to develop an integrated approach to control fusarium wilt of banana. Eight biocontrol agents were screened against Fusarium oxysporum f. sp. cubense in vitro. Among these, the Pfm strain of Pseudomonas fluorescens showed maximum growth inhibition of the pathogen and a compatible reaction with extracts of neem cake. Similar effects were shown by T. viride and T. harzianum, P.fluorescens; these agents were used further to verify efficacy under greenhouse conditions using various methods of application. Among the methods tested, soil application of biocontrol agents proved to be most effective against the wilt disease and associated vascular discolouration. Soil application of talc formulation of P. fluorescens at 10 g/plant had the least effect when measured by wilt index and vascular discolouration index. Other methods, viz., sucker dipping corm injection and capsule application showed a significant reduction in wilt index and vascular discolouration. In field trials, there were 15 treatments including soil application, sucker dipping in spore suspension, basal application of neem cake, in all possible combinations, together with chemical and uninoculated control. Two field trials in two locations each were conducted during 2000-2001 and 2001-2002 to test its efficacy. The treatment: basal application of neem cake at 0.5 kg/plant+sucker dipping in spore suspension of P. fluorescens for 15 min+soil application of P. fluorescens at 10 g/plant at 3.5 and 7 months after planting showed the greatest suppression of wilt disease and this was on par with basal application of neem cake at 0.5 kg/plant+soil application of P. fluorescens at 10 g/plant at 3.5 and 7 months after planting. Other treatments also showed significant effects in reducing wilt incidence.