Behavior of Megathyrsus maximus cv. BRS Tamani to brown leaf spot, caused by Bipolaris yamadae, as a function of nitrogen fertilization doses.
ABSTRACT - One of the diseases threatening pasture health is brown leaf spot, caused by Bipolaris yamadae, recently reported in Brazil. The objective was to assess the effect of increasing nitrogen (N) doses on the behavior and severity of brown spot in Megathyrsus maximus cv. BRS Tamani. The experi...
| Autores: | , , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2025 |
| País: | Brasil |
| Institución: | Empresa Brasileira de Pesquisa Agropecuária (Embrapa) |
| Repositorio: | Repositório Institucional da EMBRAPA (Repository Open Access to Scientific Information from EMBRAPA - Alice) |
| Idioma: | inglés |
| OAI Identifier: | oai:www.alice.cnptia.embrapa.br:doc/1179205 |
| Acceso en línea: | http://www.alice.cnptia.embrapa.br/alice/handle/doc/1179205 https://doi.org/10.1007/s42161-025-01913-2 |
| Access Level: | acceso abierto |
| Palabra clave: | Gado de Corte Panicum Maximum Pastagem Forage Fungi Leaf area Megathyrsus maximus |
| Sumario: | ABSTRACT - One of the diseases threatening pasture health is brown leaf spot, caused by Bipolaris yamadae, recently reported in Brazil. The objective was to assess the effect of increasing nitrogen (N) doses on the behavior and severity of brown spot in Megathyrsus maximus cv. BRS Tamani. The experiment followed a randomized block design with four replicates. Treatments included five N doses (0, 50, 100, 150, and 200 mg N dm-3) in the form of urea (45% N) diluted in water. Disease severity was estimated on 15 randomly selected leaves per pot at 7, 14, and 21 days after inoculation (DAI). At 14 DAI, the plants were cut 20 cm above the ground to simulate grazing effects, and the final disease severity assessment was done at 21 DAI. Chlorophyll content in 15 fully expanded leaves per pot was estimated at 7 and 14 DAI. Yield traits were determined through cutting at 14 DAI. Fertilization increased growth, yield, chlorophyll index and brown leaf spot severity. The highest nitrogen dose at 7 and 14 DAI resulted in the highest brown spot severity while the dose of 168 mg N dm-3 caused the highest severity at 21 DAI. Simulated grazing removed infected tissue and prevented an increase in severity at 21 DAI. |
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