|Solorzano Torres, Cesar|
Submitted to: Field Crops Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/23/2011
Publication Date: 6/15/2011
Citation: Solorzano Torres, C.D., Malvick, D.K. 2011. Effects of fungicide seed treatments on germination, population, and yield of maize grown from seed infected with fungal pathogens. Field Crops Research. 122(2011): 173-178. Interpretive Summary: Seedling diseases of corn can result in plant stand reduction and yield loss. Three common fungal diseases are known to infect corn seed. Most corn seed in the U.S. is treated with a combination of contact and systemic anti-fungal agents. We determined the effect of three antifungal seed treatments. on germination, plant population, and yield of corn infected with seedborne fungi. A triple treatment combination resulted in the highest plant population and yield. Two of the anti-fungal materials often had the greatest effect on increasing plant populations and yield when applied to seed with high levels of seedborne fungi. These benefits were more clearly documented with one of the seedborne diseases. The results of this research provide new knowledge on the use of corn fungicide treatment combinations not previously investigated, which corn extension agents and researchers at the federal and university level can use as a baseline to provide crop recommendations to corn farmers.
Technical Abstract: Seedborne fungi can reduce survival, growth, and yield of maize (Zea mays L.). Laboratory, field, and growth chamber experiments were conducted to determine the effects of the seed treatment fungicides fludioxonil, mefenoxam, and azoxystrobin on germination, plant population, and grain yield of maize grown from low-quality hybrid seed infected with seedborne fungal pathogens. Study I used seed of four hybrids infected at 0–54% incidence with Fusarium spp., Stenocarpella maydis, Penicillium spp., Rhizopus spp., and/or Aspergillus spp. Study II used three seed lots for each of two hybrids infected at 7–37% incidence with S. maydis. Warm and cold germination for untreated seed varied among hybrids in both studies. Warm germination of the seed lot with the highest incidence of S. maydis in study II treated with azoxystrobin and fludioxonil was significantly greater (+7%) than the nontreated control. Plant population in study I was significantly affected by seed treatment, hybrid, and their interactions. Populations were greater (=9%) for fludioxonil, fludioxonil + mefenoxam, and fludioxonil + mefenoxam + azoxystrobin treatments compared to controls. In growth chamber experiments with pasteurized soil, emergence (=5%) and plant dry weight (=14%) were both greater than controls only with the triple seed treatment. Plant populations in study II for all seed treatments except mefenoxam and azoxystrobin alone were greater (=4%) than controls. Yield in study I was significantly affected by hybrid and seed treatment. Yield for one hybrid was higher (=20%) than the control with all seed treatments except fludioxonil, whereas yield with another hybrid was consistently greater (=26%) only with the triple seed treatment. Yield in study II was significantly affected by hybrid, seed treatment, and their interactions. Yield was greater (=8%) than the controls for all seed treatments with one hybrid and with all (=5%) except azoxystrobin for the other hybrid. Highest yields occurred with the triple seed treatment. Results indicate that fludioxonil and azoxystrobin can increase germination, population, and yield of maize grown from seed infected by S. maydis and other fungi.