Abstract
In Brazil, Gibberella ear rot (GER) of maize is caused mainly by Fusarium meridionale, whereas F. graminearum is a minor contributor. To test the hypothesis that F. meridionale is more aggressive than F. graminearum on maize, six experiments were conducted in the south (summer) and one in the central-south (winter), totaling seven conditions (year × location × hybrid). Treatments consisted of F. graminearum or F. meridionale (two isolates of each) inoculated once 4 days after silk, inoculated sequentially and alternately (F. graminearum ! F. meridionale or F. meridionale ! F. graminearum) 6 days apart, or (in the central-south) inoculated sequentially without alternating species (F. meridionale ! F. meridionale or F. graminearum ! F. graminearum). Overall, severity was two times greater in the south (37.0%), where summer temperatures were warmer (20 to 25∘C) than in central-south. In the south, severity was greatest in F. meridionale treatments (67.8%); followed by F. meridionale ! F. graminearum (41.1%), then F. graminearum ! F. meridionale (19.4%), and lowest in F. graminearum (2.1%), suggesting an antagonistic relationship. In the central-south (15 to 20∘C), severity was generally higher in the sequential nonalternating inoculation treatments (F. meridionale ! F. meridionale or F. graminearum ! F. graminearum) than when either species was inoculated only once. Only nivalenol (NIV) or deoxynivalenol was detected when F. meridionale or F. graminearum, respectively, was inoculated singly, or sequentially with no alternation. Both toxins were found in grains harvested from the F. meridionale ! F. graminearum treatment, whereas only NIV was found in kernels from the F. graminearum ! F. meridionale treatment, suggesting that F. meridionale was more competitive than F. graminearum in coinoculations. The dominance of F. meridionale as a cause of GER in Brazil may be due in part to its higher aggressiveness and competitiveness compared with F. graminearum.
| Original language | English |
|---|---|
| Pages (from-to) | 1774-1781 |
| Number of pages | 8 |
| Journal | Phytopathology |
| Volume | 111 |
| Issue number | 10 |
| DOIs | |
| State | Published - Oct 2021 |
Bibliographical note
Publisher Copyright:© 2021 The American Phytopathological Society
Funding
Funding: F. J. Machado thanks the Programa de Pós-graduac¸ão em Fitopatologia, CNPq-Conselho Nacional de Desenvolvimento Científico e Tecnológico for providing a graduate scholarship, and CAPES-Coordenac¸ão de Aperfeic¸oamento de Pes-soal de Nível Superior for providing a sandwich fellowship (PDSE). P. R. Kuhnem thanks the Programa de Pós-graduac¸ão em Fitotecnia and CNPq for providing a graduate scholarship. Thanks are given to CNPq for providing a research fellowship to E. M. Del Ponte and R. T. Casa. This work was partially supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture, Multistate Project (1008664). F. J. Machado thanks the Programa de P?s-gradua??o em Fitopatologia, CNPq-Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico for providing a graduate scholarship, and CAPES-Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior for providing a sandwich fellowship (PDSE). P. R. Kuhnem thanks the Programa de P?s-gradua??o em Fitotecnia and CNPq for providing a graduate scholarship. Thanks are given to CNPq for providing a research fellowship to E. M. Del Ponte and R. T. Casa. This work was partially supported by the National Institute of Food and Agriculture, U.S. Department of Agriculture, Multistate Project (1008664).
| Funders | Funder number |
|---|---|
| CAPES-Coordenac¸ão de Aperfeic¸oamento de Pes-soal de Nível Superior | |
| CNPq-Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico | |
| U.S. Department of Agriculture | 1008664 |
| National Institute of Food and Agriculture | |
| Conselho Nacional de Desenvolvimento Científico e Tecnológico |
Keywords
- Fusarium graminearum species complex
- Nivalenol
- Zea mays
ASJC Scopus subject areas
- Agronomy and Crop Science
- Plant Science