Susceptibility of maize varieties to opposite mating type strains of Fusarium verticillioides

Fusarium verticillioides the causal agent of maize ear rot is world wide distributed heterothalic species with dimictic mating system of reproduction. Presented paper summarizes results of fourth years (2007 – 2010) field studies analyzing disease severity of maize plant after inoculation with opposite mating type strains of the fungus. Genotypes of fourth maize cultivars (Zea mays var indentata, Zea mays var indurata, Zea mays var everta and Zea mays var saccharata) were inoculated with two F. verticillioides isolates KFI 2856 and KFI 3011 representing respectively MAT1-1 and MAT1-2 subpopulation of the species. Infection degree was evaluated using six degree (0 – 5) rating scale at seven days intervals after inoculation. Obtained results revealed that mating type of analyzed species had not significant impact on maize ear infection in any of growing seasons. Reaction of particular maize varieties against ear rot due to F. verticillioides in particular years were stable. The lowest infection degree exhibited plants of Zea mays var everta while the highest susceptibility Zea mays var saccharata. Regardless of cropping seasons significantly less was affected genotypes of sweet maize (Su1) than super sweet (Sh2).