Trichoderma SPECIES EFFECT ON THE INCIDENCE BY F. verticillioides IN FOUR MAIZ GENOTYPES

Background. Fusarium verticillioides is a fungus most frequently isolated from corn cobs and the most widely distributed in the world; affecting a wide range of hosts and contaminated products with mycotoxins. Objective. The present study aimed to determine the incidence of F. verticillioides in four maize genotypes treated with Trichoderma strains as biocontrol under field conditions. Methodology. Three Trichoderma strains were inoculated by three inoculation methods to test their effectiveness in controlling the fungus F. verticillioides. Four maize genotypes were used to determine this effect. The antagonist strains were inoculated at sowing time as seed inoculation and foliar spray applied in stage R2 and R3. Results. Fusarium verticillioides was identified morphologically and molecularly. The three strains significantly reduced the incidence of the fungus, however T. harzianum T1-4 was the one that presented the best control. The evaluated methods, seed inoculation and foliar spraying evaluated simultaneously significantly reduced the incidence of the phytopathogen. The Mestizo Diamante genotype presented a better response to the invasion by F. verticillioides in interaction with the antagonist strains. Implications. Due to the limited field work for the biological control of F. verticillioides, the present results contribute to this scarce information. Conclusion. Trichoderma species reduced the incidence of F. verticillioides in maize genotypes from the state of Veracruz.