In vitro efficacy of newer chemical fungicides against Fusarium oxysporum f.s.p. cubense Race 1 and Tropical Race 4

Abstract

Banana (Musa spp.) is one of the most important fruit crops worldwide, with India being the largest producer. However, banana cultivation is severely threatened by Fusarium wilt (Panama wilt), caused by Fusarium oxysporum f. sp. cubense (Foc), particularly its tropical race 4 (TR4), which is highly virulent and affects nearly all banana cultivars. The soil-borne nature and long-term survival ability of the pathogen make its management extremely difficult. The present investigation was undertaken to evaluate the efficacy of two new generation fungicides, Tebuconazole 50% + Trifloxystrobin 25% WG (Nativo) and Propiconazole 25% EC (Tilt), against Fusarium oxysporum f. sp. cubense race 1 and tropical race 4 under in vitro conditions. The experiment was conducted using the poison food technique at five concentrations (50, 100, 150, 250 and 500 ppm). Results revealed that Propiconazole 25% EC exhibited complete inhibition (100%) of both Foc race 1 and TR4 at all tested concentrations. Tebuconazole 50% + Trifloxystrobin 25% WG showed partial inhibition against Foc race 1, ranging from 68.03% at 50 ppm to 81.70% at 500 ppm, while it completely inhibited (100%) the mycelial growth of Foc TR4 at all concentrations. The study indicates that new generation systemic fungicides, particularly Propiconazole and the combination fungicide Tebuconazole + Trifloxystrobin, possess strong antifungal activity against Foc races and may be useful components in integrated management strategies for Fusarium wilt of banana.