Breeding for resistance and integrated management of web blight in common beans (Phaseolus vulgaris L.)

Authors: BEAVER, JAMES - University Of Puerto Rico; MARTINEZ FIGUEROA, HECTOR - Institute Of Agricultural Science And Technology (ICTA); GODOY DE LUTZ, GRACIELA - Dominican Institute For Agricultural And Forestry Research (IDIAF); ESTEVEZ DE JENSEN, CONSUELO - University Of Puerto Rico; Porch, Timothy - Tim; ROSAS, JUAN - Zamorano, Panamerican School Of Agriculture

Submitted to: Crop Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/13/2021
Publication Date: 10/20/2021
Citation: Beaver, J.S., Martinez Figueroa, H., Godoy De Lutz, G., Estevez De Jensen, C., Porch, T.G., Rosas, J.C. 2021. Breeding for resistance and integrated management of web blight in common beans (Phaseolus vulgaris L.). Crop Science. 62:20-35. https://doi.org/10.1002/csc2.20658.
DOI: https://doi.org/10.1002/csc2.20658

Interpretive Summary: Web blight is a serious disease of common bean in the humid tropics causing significant losses in both seed yield and seed quality. At present, only moderate levels of resistance have been identified. Greenhouse screening has identified genotypes that possess physiological resistance to specific isolates of the pathogen. Agronomic traits such as an erect plant habit and an open canopy and resistance to common bacterial blight, complement physiological resistance. Leaf and seed damage and lesion size are criteria that have been successfully used to screen bean for web blight resistance in the greenhouse and in the field. Pedigree selection has been successfully used to develop and release bean cultivars having moderate levels of resistance. Recurrent selection has been used to broaden the genetic base and to produce progeny having higher levels web blight resistance. Utilization of sources of resistance from the primary and secondary gene pools are recommended to combine resistance genes from diverse sources. Earlier maturity, deep tap roots and terminal drought tolerance may be desirable traits for farmers who plant later in the wet season to avoid web blight. Relay intercropping of climbing common or tepary beans would provide more disease avoidance than monoculture. Seed production during the dry season using irrigation would help to reduce infection of the web blight pathogen and other seed-borne diseases. Resistance to seed transmission of the disease would be a valuable trait. Production techniques used by organic bean producers, such as the use of a roller-crimper to create a dead vegetative cover, might be useful for minimum tillage that helps to reduce the spread of the disease. Biological control has the potential to contribute to the management of web blight and complement genetic resistance.

Technical Abstract: Web blight, caused by Thanatephorus cucumeris (Frank) Donk, is a serious disease of common bean (Phaseolus vulgaris L.) in the humid tropics causing significant losses in both seed yield and seed quality. At present, only moderate levels of resistance have been identified. Greenhouse screening has identified genotypes that possess physiological resistance to specific isolates of the pathogen. Agronomic traits such as an erect plant habit and an open canopy and resistance to common bacterial blight, caused by Xanthomonas axonopodis pv. phaseoli, complement physiological resistance. Leaf and seed damage and lesion size are criteria that have been successfully used to screen bean for web blight resistance in the greenhouse and in the field. Pedigree selection has been successfully used to develop and release bean cultivars having moderate levels of resistance. Recurrent selection has been used to broaden the genetic base and to produce progeny having higher levels web blight resistance. Utilization of sources of resistance from the primary and secondary gene pools are recommended to combine resistance genes from diverse sources. Earlier maturity, deep tap roots and terminal drought tolerance may be desirable traits for farmers who plant later in the wet season to avoid web blight. Relay intercropping of climbing common or tepary (Phaseolus acutifolius L.) beans would provide more disease avoidance than monoculture. Seed production during the dry season using irrigation would help to reduce infection of the web blight pathogen and other seed-borne diseases. Resistance to seed transmission of the disease would be a valuable trait. Production techniques used by organic bean producers, such as the use of a roller-crimper to create a dead vegetative cover, might be useful for minimum tillage that helps to reduce the spread of the disease. Biological control has the potential to contribute to the management of web blight and complement genetic resistance.