Baseline sensitivity of Fusarium species associated with Fusarium diseases to metconazole, triticonazole, and thiabendazole fungicides.

摘要

Baseline sensitivity was determined using in vitro radial growth assay for Fusarium oxysporum, Fusarium graminearum, and a novel uncharacterized Fusarium sp. nov. from sugarbeet, and F. sambucinum from potato, to metconazole, triticonazole, and thiabendazole. All the isolates from sugarbeet and a thiabendazole-sensitive F. sambucinum isolate were sensitive to the tested fungicides. A thiabendazole-resistant isolate of F. sambucinum was resistant to thiabendazole but sensitive to the other two fungicides. The EC₅₀ values of F. oxysporum, F. graminearum, and F. sp. nov. for triticonazole were 0.51 micro g ml-1, 2.15 micro g ml-1, and 0.04 micro g ml-1, respectively. The EC₅₀ values of F. oxysporum, F. graminearum, and F. sp. nov. for metconazole were 0.04 micro g ml-1, 0.03 micro g ml-1, and 0.02 micro g ml-1, respectively. The EC₅₀ values of F. oxysporum, F. graminearum, and F. sp. nov. for thiabendazole were 0.57 micro g ml-1, 0.54 micro g ml-1, and 0.64 micro g ml-1, respectively. Generally, a higher concentration of triticonazole and thiabendazole compared to metconazole were required to reduce colony growth by 50%. The low EC₅₀ values of metconazole, triticonazole, and thiabendazole for the Fusarium species tested suggest that they are potential candidates for control of Fusarium diseases of sugarbeet Research is needed to determine the effectiveness of these fungicides for control of Fusarium diseases under field conditions.