Resistance to black rot in a Spanish Brassica collection

Xanthomonas campestris pv. campestris (Xcc), causal agent of black rot, is widely distributed around the world in Brassica crops causing severe yield losses. The seedborne bacteria can survive in crop debris or crucifer weeds, introducing in the plant through hydathodes and wounds. While in warm and...

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Detalles Bibliográficos
Autores: Lema Márquez, Margarita, Soengas, Pilar, Velasco Pazos, Pablo, Abilleira Ambroa, Rosaura, Cartea González, María Elena
Tipo de recurso: artículo
Fecha de publicación:2011
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/46299
Acceso en línea:http://hdl.handle.net/10261/46299
Access Level:acceso abierto
Palabra clave:Xanthomonas campestris
Black rot
Brassica crops
Resistance
Descripción
Sumario:Xanthomonas campestris pv. campestris (Xcc), causal agent of black rot, is widely distributed around the world in Brassica crops causing severe yield losses. The seedborne bacteria can survive in crop debris or crucifer weeds, introducing in the plant through hydathodes and wounds. While in warm and humid regions Xcc can cause plant dead, in coastal temperate areas it produces necrotic lesions on leaf margin, which decrease the value of the product on fresh market. In northwestern Spain, black rot has been recently identified in several Brassica crops (Lema et al. 2008). In this region, the production is mainly by small growers who do not use healthy plant material and disease-free seeds and, consequently, the pathogen can rapidly widespread. No studies involving either the pathogen or screens for resistance in this area have been conducted. For disease control the use of resistant cultivars is highly recommended but for most Brassica crops, especially in local crops, resistant cultivars are not offered and sources of resistance are very limited or even unknown. In the last years, the search for new sources of resistance has been race-specific since the existence of six races of the pathogen was described by Vicente et al. (2001). In addition to monogenic race-specific, a quantitative race-nonspecific resistance has been described (Soengas et al. 2007, Taylor et al. 2002). Recently, Fargier and Manceau (2007) added three new races (7 to 9), being races 1 and 4 are the most virulent and widespread, accounting for most black rot cases around the world. Sources of resistance to Xcc in Brassica genomes have been examined by different researchers but the use of resistant cultivars has only had limited success and available sources with useful levels of resistance are scarce. Moreover, most of these works focused in cabbage due to its economical value, while the search for resistance in other Brassica crops has been more restricted. Therefore, the objective of this work was to identify new sources of resistance to races 1 and 4 of Xcc in several Brassica crops.