The role of husk traits in maize susceptibility to Fusarium verticillioides: A multi-location study in northern Italy

Fusarium disease and the consequent mycotoxin accumulation pose significant problem in maize cultivation, with fumonisins produced by Fusarium verticillioides posing a global health concern. To address this issue, a range of preventive measures (e.g. crop management techniques) can be implemented to minimize fungal infections. A promising strategy to counteract this issue involves the selection of genotypes with greater resistance to fungal pathogens. This approach has the potential to reduce the reliance on chemical inputs for controlling fungus growth or indirect infection vectors. Leveraging genetic approaches can help improve the economic sustainability of agriculture in the face of climate change challenges. In the present work, we assessed the importance of two husk leaf traits (coverage and number), their association with F. verticillioides infection, fumonisin content, and their potential influence on crop yield. The study was conducted in three locations in the North of Italy and 38 hybrids with varying resistance to F. Verticillioides were compared. The results obtained showed that husk coverage has a pivotal role not only in protecting maize ears from Fusarium infection but have also a significant impact on crop yield: a significant positive correlation was found between husk coverage and yield in all three locations (r = 0.33185; r = 0.51327 and r = 0.51207, respectively). Furthermore, in the field of Vicenza, a significant negative correlation was found between husk coverage and Fusarium severity (r = -0.41492). Husk coverage emerges as an important trait that merits inclusion in maize breeding programs, given its protective role against fungal infections and its favourable influence on both yield and grain quality.