Heritability of resistance to web blight in five common bean populations

• Published in: Crop science Vol. 37; no. 3; pp. 780 - 783
• Main Authors: Montoya, C.A, Beaver, J.S, Rodriguez, R, Miklas, P.N, Godoy-Lutz, G
• Format: Journal Article
• Language: English
• Published: Madison, WI Crop Science Society of America 01-05-1997; American Society of Agronomy
• Subjects: Agronomy. Soil science and plant productions; Beans; Biological and medical sciences; Biology; CROISEMENT; Crops; CROSSBREEDING; CRUZAMIENTO; Disease; DISEASE RESISTANCE; Diseases and pests; DOMINICAN REPUBLIC; ENSAYO; Fundamental and applied biological sciences. Psychology; Fungal diseases of plants; Genes; Genetic aspects; Genetics and breeding of economic plants; HEREDABILIDAD; HERITABILITE; HERITABILITY; HIBRIDOS; HYBRIDE; HYBRIDS; INFECCION; INFECTION; Kidney bean; LINES; Pest resistance; PHASEOLUS VULGARIS; Plant pathogens; PORTO RICO; PUERTO RICO; REPUBLICA DOMINICANA; REPUBLIQUE DOMINICAINE; RESISTANCE AUX MALADIES; RESISTENCIA A LA ENFERMEDAD; RHIZOCTONIA SOLANI; SCREENING; SELECCION; SELECTION; SINTOMAS; SYMPTOME; SYMPTOMS; TESTAGE; TESTING; VARIEDADES; VARIETAL RESISTANCE; Varietal selection. Specialized plant breeding, plant breeding aims; VARIETE; VARIETIES; Central America; Puerto Rico; America; West Indies; Greater Antilles; Plant pathology; Genetic inheritance; Plant pathogen; Mycosis; Tropical zone; Fungi; Disease resistance; Dicotyledones; Angiospermae; Genetics; Rhizoctonia solani; Fungi Imperfecti; Greenhouse study; Thallophyta; Tropical crop; Varietal selection; Fungus resistance; Infection; Grain legume; Screening; Sensitivity resistance; Leguminosae; Vegetable crop; Phaseolus vulgaris; Genetic improvement; Spermatophyta; Heritability
• ISSN: 0011-183X; 1435-0653
• DOI: 10.2135/cropsci1997.0011183X003700030014x

Common bean (Phaseolus vulgaris L.) production in the humid tropics would benefit from the selection of cultivars with greater levels of resistance to web blight, a devastating disease caused by Rhizoctonia solani Kuhn. This will require screening techniques that are sensitive enough to detect moderate levels of resistance. Greenhouse experiments evaluated the effectiveness of a droplet inoculation technique for screening five F5:6 segregating populations for resistance to web blight. Another objective was to estimate the heritability of resistance to web blight in five common bean populations. Significant differences in lesion size were detected among F6 lines within each population. Lines with less web blight infection than the resistant parent MUS83 were observed in each population. This suggests that both parents contributed to the resistance of the progeny. Narrow sense heritability estimates for web blight reaction ranged from 0.61 to 0.79. These relatively high heritabilities suggest that selection for smaller lesion size may be effective in earlier generations when MUS83 is used as a source of resistance to web blight. Physiological resistance to web blight, as measured by lesion size by means of the droplet inoculation technique, will need to be combined with disease avoidance traits such as erect architecture to obtain effective resistance in the field. Five lines from the MUS83 x DOR483 population with smaller lesion sizes in the greenhouse had moderate to low levels of web blight infection in field experiments conducted in Puerto Rico and the Dominican Republic