Resumo

MEDINA-OSTI, Fabiola; GUTIERREZ-DIEZ, Adriana; OCHOA-ASCENCIO, Salvador  e  SINAGAWA-GARCIA., Sugey Ramona. In vitro sensitivity of Fusarium sacchari isolated from sugar cane to five fungicides. Rev. mex. fitopatol [online]. 2022, vol.40, n.3, pp.447-457.  Epub 14-Nov-2022. ISSN 2007-8080.  https://doi.org/10.18781/r.mex.fit.2206-1.

The present study had the objective of evaluating the in vitro sensitivity of Fusarium sacchari to five fungicides of different chemical groups. An isolate of F. sacchari obtained from sugarcane plants (Saccharum officinarum) with wilt symptoms and identified morphologically and molecularly by the characteristics of the genus Fusarium and amplification of the ITS and TEF regions, respectively, was used to evaluate the fungicides azoxystrobin, difenoconazole, hymexazole, cyprodinil and thiabendazole, at concentrations of 1, 10, 100 and 1000 µg mL-1, using the poison plate technique. The effect of the fungicides and EC50 was determined by the percentage inhibition of F. sacchari growth with respect to the growth on the plates without fungicide. The fungicides difenoconazole at 1000 µg mL-1 and thiabendazole at 100, 1000 and 10 µg mL-1 were statistically equal and presented the highest mycelial growth inhibition percentages (93.5 and 92.1, 91.4 and 89.8 %, respectively). The lowest EC50 values were presented by difenoconazole (9.2 µg mL-1), thiabendazole (9.9 µg mL-1) and cyprodinil (10.6 µg mL-1). In conclusion, F. sacchari presented higher in vitro sensitivity to the fungicides difenoconazole (1000 µg mL-1) and thiabendazole (100, 1000 and 10 µg mL-1).

Palavras-chave : Pokkah boeng; sugarcane; inhibition; EC₅₀.