In vitro sensitivity of Fusarium sacchari isolated from sugar cane to five fungicides

Abstract

<p>The present study had the objective of evaluating the<em> in vitro</em> sensitivity of <em>Fusarium sacchari</em> to five fungicides of different chemical groups. An isolate of <em>F. sacchari</em> obtained from sugarcane plants (<em>Saccharum officinarum</em>) with wilt symptoms and identified morphologically and molecularly by the characteristics of the genus <em>Fusarium</em> 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 ?g mL-1, using the poison plate technique. The effect of the fungicides and EC50 was determined by the percentage inhibition of <em>F. sacchari</em> growth with respect to the growth on the plates without fungicide. The fungicides difenoconazole at 1000 ?g mL-1 and thiabendazole at 100, 1000 and 10 ?g 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 ?g mL-1), thiabendazole (9.9 ?g mL-1) and cyprodinil (10.6 ?g mL-1). In conclusion, <em>F. sacchari</em> presented higher <em>in vitro</em> sensitivity to the fungicides difenoconazole (1000 ?g mL-1) and thiabendazole (100, 1000 and 10 ?g mL-1).</p>