Investigating the Antagonistic Effects of Novel Combination Fungicides against Fusarium oxysporum f. sp. ricini under In-vitro Conditions

Aim: The study aimed to assess the efficacy of nine novel fungicide combinations against Fusarium oxysporum f. sp. ricini, the causal agent of wilt disease in castor. Methodology: The efficacy of fungicides was evaluated using the poisoned food technique under in-vitro conditions. Radial mycelial growth of the pathogen was measured across various concentrations (100 to 1000 ppm) of the fungicide combinations to determine their impact on mycelial inhibition. Results: Results indicated a substantial reduction in radial mycelial growth with increased fungicide concentration. Among the tested fungicides, Tebuconazole + Trifloxystrobin and Prochloraz + Tebuconazole recorded complete mycelial inhibition (100 %) at all the tested concentrations, demonstrating significant fungicidal activity followed by Hexaconazole + Captan with a mean mycelial inhibition of 85.2 %, indicating strong potential for disease management. In contrast, the least mean mycelial inhibition (24.7 %) was observed with Thiophanate methyl + Pyraclostrobin. Conclusion: These findings underscored the importance of selecting effective fungicide combinations to manage F. oxysporum f. sp. ricini, thereby enhancing crop protection and agricultural sustainability.