EFFECT OF 3 SYSTEMIC FUNGICIDES ON DEOXYNIVALENOL (VOMITOXIN) PRODUCTION BY FUSARIUM-GRAMINEARUM IN WHEAT

The effect of triadimefon, propiconazole and thiabendazole fungicides on the growth of Fusarium graminearum and the production of deoxynivalenol in wheat was investigated in a field trial. The heads of wheat plants were infected with F. graminearum spores (1 x 10(5) conidia mL-1, approximately 62.5 mL m-2) 2 d following anthesis. Triadimefon (Bayleton 1.8 E.C), propiconazole (Tilt 3.6 E.C) and thiabendazole (Mertect 340-F) were sprayed at the dosages of 60, 120, and 360 g a.i. ha-1, respectively. Treatments of wheat plants with the fungicides were conducted at three time schedules: (1) one application at 2 d before inoculation, (2) one application at 2 d after incoulation, and (3) two applications at 2 d before and 2 d after the inoculation of wheat plants with F. graminearum. Treatments with triadimefon and propiconazole fungicides resulted in 39-61% and 34-79% decreases in F. graminearum infection and deoxynivalenol levels, respectively. Although treatment with thiabendazole resulted in the maximum reduction (83%) in deoxynivalenol level, it had no significant effect on F. graminearum infection.