Role of the fungicide seed dressing in controlling seed-borne Fusarium spp. Infection and in enhancing the early development and grain yield of maize

Fusarium spp. are key pathogens in maize seeds and seedlings. The aim of this study has been to evaluate the effects of applying fungicides to maize seeds to increase the survival of seedlings and to enhance the early vigor and grain yield of the plants. The protective effects of 2-way (fludioxonil, metalaxil-M) and four-way (fludioxonil, metalaxil-M, azoxystrobin, thiabendazole) fungicide seed treatments were compared with an F. verticillioides seed infected control in 11 field trials carried out in North Italy. A second study focused on the impact F. verticillioides and F. graminearum seed-borne infection on plant growth and on the possible advantages of applying the previously reported seed dressing. The seed dressing increased the plant density, vigor during the whole vegetative growth cycle for all the production situations, and grain yield. F. verticillioides led to a higher seedling mortality than F. graminearum, while both species reduced plant growth and delayed the flowering date. Seed-borne infection has an important impact on both the population and vigor of maize plants. The four-way fungicide enhanced both the defense of the seedlings and the vigor of F. verticillioides infected plants, which in turn resulted in a significant improvement in grain yield, compared to a conventional two-way fungicide.