Phytosanitary evaluation of commercial maize hybrids in Italy

Seed health is one of the quality characteristics that must be assessed during the seed certification process. In this study, the freezing blotter method was used to detect fungi present in a total of 102 and 75 maize seed lots produced in 2019 and 2020 respectively, by eight companies in different geographic areas. The analysis of the seed samples produced in 2019 showed significant differences among companies and countries in the percentage of infection with Aspergillus spp. and Fusarium spp. The results obtained with the samples produced in 2020 were not statistically different. PCR-based tests were carried out on 90 isolates to identify the fungal species and differentiate the mycotoxigenic isolates. The results showed that Fusarium verticillioides and Aspergillus flavus were the most common species infecting seed and that 46.5% of F. verticillioides and 57.1% of A. flavus isolates were toxigenic. The most effective seed treatments against Fusarium spp. and Aspergillus spp. contained azoxystrobin and prothioconazole.