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FICHA TÉCNICA Cochliobolus Miyabeanus (Bipolaris Oryzae)

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FICHA TÉCNICA Cochliobolus Miyabeanus (Bipolaris Oryzae) DIRECCIÓN GENERAL DE SANIDAD VEGETAL DIRECCIÓN DEL CENTRO NACIONAL DE REFERENCIA FITOSANITARIA FICHA TÉCNICA Mancha marrón del arroz Cochliobolus miyabeanus (Bipolaris oryzae) DIRECCIÓN GENERAL DE SANIDAD VEGETAL DIRECCIÓN DEL CENTRO NACIONAL DE REFERENCIA FITOSANITARIA CONTENIDO IDENTIDAD .................................................................................................................................................................................. 1 Nombre científico ...................................................................................................................................... 1 Sinónimos ..................................................................................................................................................... 1 Clasificación taxonómica ......................................................................................................................... 1 Nombres comunes .................................................................................................................................... 1 IMPORTANCIA ECONÓMICA DE LA PLAGA .................................................................................................................. 1 SITUACIÓN EN MÉXICO ........................................................................................................................................................ 2 HOSPEDANTES ........................................................................................................................................................................ 2 DISTRIBUCIÓN MUNDIAL..................................................................................................................................................... 2 DESCRIPCIÓN MORFOLÓGICA .......................................................................................................................................... 3 ASPECTOS BIOLÓGICOS ...................................................................................................................................................... 4 SÍNTOMAS .................................................................................................................................................................................. 5 ASPECTOS EPIDEMIOLÓGICOS ........................................................................................................................................ 9 METODOS DE DETECCIÓN/DIAGNÓSTICO .................................................................................................................. 9 MUESTRO ................................................................................................................................................................................. 10 MANEJO FITOSANITARIO ................................................................................................................................................. 12 Cultural ........................................................................................................................................................ 12 Genético. ..................................................................................................................................................... 12 Químico ....................................................................................................................................................... 12 Biológico ...................................................................................................................................................... 13 LITERATURA CITADA .......................................................................................................................................................... 14 DIRECCIÓN GENERAL DE SANIDAD VEGETAL DIRECCIÓN DEL CENTRO NACIONAL DE REFERENCIA FITOSANITARIA IDENTIDAD IMPORTANCIA ECONÓMICA DE LA PLAGA Nombre científico Barnwal et al. (2013) y Schwanck et al. (2015) Cochliobolus miyabeanus (S. Ito & Kurib) mencionaron que la mancha café del arroz 1942 causa pérdidas en un rango de 4 a 52%. Sin embargo, Lee (1992) reportó que C. Sinónimos miyabeanus (= Bipolaris oryzae) fue Bipolaris oryzae 1959 (anamorfo) responsable de una epidemia en 1942 en Ophiobolus miyabeanus 1931 Bengal, donde se reportaron pérdidas del 40 Drechslera oryzae 1966 al 90% de la producción. Los granos Helminthosporium oryzae 1900 infectados no son aptos para el consumo Luttrellia oryzae 1978 humano, debido a que el hongo produce una Spondylocladium macrocapum 1954 toxina llamada ofiobolina. Por su parte, De la (Mycobank, 2020; EPPO, 2020). Paz et al. (2006), mencionaron que el patógeno puede reducir el rendimiento del Clasificación taxonómica cultivo en un rango de 6 a 90% y del 10 al Dominio o Reino: Fungi 58% de muerte de plántulas. Menezes et al. Phyllum: Ascomycota (2014) reportaron que la dinámica (incidencia Subphyllum: Pezizomycotina y severidad) de la enfermedad está Clase: Dothideomycetes influenciada por el clima y las prácticas de Subclase: Pleosporomycetidae manejo del cultivo y de la enfermedad, la cual Orden: Pleosporales varía significativamente entre cada año y Familia: Pleosporaceae décadas. Género: Cochliobolus Especie: C. miyabeanus En el estado de Morelos, México, Barrios- (EPPO, 2020) Gómez et al. (2016a) reportaron a C. miyabeanus (=Bipolaris oryzae) y otros Nombres comunes patógenos como agentes causales del Español: mancha marrón del arroz, Mancha manchado del grano, complejo que llega a café del follaje y de la semilla del afectar el grano al reducir el peso hasta un arroz, 40%, la germinación, así como el llenado de Ingles: brown spot of rice, ear blight of rice, granos. Salazar-Santiago et al. (2019) y García leaf blight of rice, panicle blight of rice, Angulo et al. (2011), señalaron que en México seedling blight of rice (EPPO, 2020). es uno de los principales hongos fitopatógenos que afectan el cultivo del arroz. 1 DIRECCIÓN GENERAL DE SANIDAD VEGETAL DIRECCIÓN DEL CENTRO NACIONAL DE REFERENCIA FITOSANITARIA SITUACIÓN EN MÉXICO de arroz de Asia, América y África (De la Paz De acuerdo con la Norma Internacional para et al., 2006) [Figura 1, Cuadro 1]. Medidas Fitosanitarias (NIMF) No. 8 “Determinación de la situación de una plaga Cuadro 1. Países con presencia de en un área” (CIPF, 2017), Cochliobolus Cochliobolus miyabeanus, agrupados por miyabeanus se encuentra Presente en continente. Créditos: CABI, 1991. México: en áreas sembradas con cultivos Continente País hospedantes. África Angola, Chad, Egipto, Gabón, Gambia, Ghana, Guinea, Costa de Marfil, Madagascar, Malawi, Mauricio, HOSPEDANTES Marruecos, Mozambique, Níger, Archana et al. (2014), mencionaron que C. Nigeria, Senegal, Sierra Leona, miyabeanus afecta 23 especies de pastos y Sudáfrica, Sudán , Tanzania, Togo, 20 especies del género Oryza, entre los cuales Uganda, Zaire, Zambia, Zimbabue. afecta a Zizania palustris (Castell-Miller et al., Asia Afganistán, Islas Andamán, 2011), además de Panicum virgatum Bangladesh, Bután, Brunei, Birmania, (Manamgoda et al., 2014). Camboya, China, India, Indonesia, Irán, Iraq, Japón, Corea, Laos, Malasia, Por otro lado Manamgoda et al. (2011), Nepal, Pakistán, Filipinas, Sri Lanka, reportan como hospedantes de C. Taiwán, Tailandia, Turquía, Rusia, Uzbekistán, Vietnam. miyabeanus a: Cosmos bipinnatus Europa Francia, Grecia, Italia, Portugal, (Asteraceae), Cordia trichotoma España, Suiza. (Boraginaceae), Alopecurus aequalis, A. América Bolivia, Brasil, Costa Rica, Colombia, geniculatus, Eleusine indica, Ischaemum Cuba, Guyana francesa, Guyana, rugosum, Leersia hexandra, Oryza Guatemala, Estados Unidos, Jamaica, australiensis, O. glaberrima, O. latifolia, O. México, República Dominicana, sativa, O. rufipogon, Panicum colonum, P. Honduras, Nicaragua, Panamá, maximum, P. virgatum, Setaria italica, Puerto Rico, Salvador, Trinidad y Triticum aestivum, Zea mays, Zizania Tobago, Espirito Santo, Minas Gerais, Pernambuco, Perú, Surinam, palustris y Z. aquatic (Poaceae). Uruguay, Venezuela. Oceanía Australia, Territorio del Norte, DISTRIBUCIÓN MUNDIAL Australia Occidental, Fiyi, Polinesia La mancha café del arroz presenta una Francesa, Nueva Caledonia, Papúa y distribución mundial, en países productores Nueva Guinea, Islas Salomón, Tahití. 2 DIRECCIÓN GENERAL DE SANIDAD VEGETAL DIRECCIÓN DEL CENTRO NACIONAL DE REFERENCIA FITOSANITARIA Figura 1. Distribución mundial de Cochliobolus miyabeanus (CABI, 2020). DESCRIPCIÓN MORFOLÓGICA café pálido a café oliváceo, brillantes en el Los peritecios son de color café oscuro de ápice, septados, más de 600 µm de longitud forma globosa a elíptica de 360 a 780 µm de y de 4 a 8 micras de ancho. Los conidios son diámetro con un cuello cónico a cilíndrico de fusoides o clavados, algunas veces casi 98-200 x 55-110 µm; las ascas son clavadas a cilíndricos, generalmente curvados, de color cilíndricas o ampliamente fusiforme, rectas o café brillante a café dorado, de 6 a 14 septos y ligeramente curveadas y bitunicadas de 140- de 63-153 X 14-22 µm, frecuentemente con un 235 x 21-26 µm; las ascosporas son hialinas a hilum ligeramente sobresaliente que puede café oliváceo brillante, filiformes a ser brillante u oscuro. Los conidios flageliformes, ensanchadas en la parte media frecuentemente germinan por uno o por y atenuadas hacia los extremos de 7 a 12 ambos polos celulares (Lee, 1992) [Figura 2], en septos rodeado por una vaina muscilaginosa medio de cultivo son de color gris a oliva o (Lee, 1992). blanco (Sunder et al., 2014). Los conidióforos
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