Genetic Variation for Resistance to Ear Rots and Mycotoxins Contamination in Early European Maize Inbred Lines

Ear rots caused by Fusarium spp. are a major concern in many maize (Zea mays L.)-growing regions of the world. Our objectives were (i) to evaluate a set of European maize inbreds for resistance to ear rots and mycotoxin concentrations, (ii) to estimate variance components and heritabilities, and (iii) to compute correlations among resistance traits. Forty-two inbreds were evaluated for resistance to F. graminearum in four environments, and 21 inbreds were evaluated for resistance to F. verticillioides in three environments, under artificial inoculation. Data were recorded on severity of Gibberella (AGER) and Fusarium ear rots and accumulation of deoxynivalenol (DON), zearalenone, and fumonisins. Artificial inoculation was effective particularly for Gibberella ear rot. Genotypic and genotype x environment interaction variances were generally significant. Heritability estimates were moderate to high. Disease severity had strong correlations with respective mycotoxin concentrations. Selection for resistance is expected to have favorable correlated response for mycotoxins particularly with respect to AGER and DON (r(p) = 0.94). We recommend conducting initial selection on the basis of visual ratings and evaluate the selected elite material for mycotoxin concentrations.