Characterization of the Angular Leaf Spot Resistance Gene Present in Common Bean Cultivar Ouro Negro

Abstract

Angular leaf spot (ALS), incited by the fungus Pseudocercospora griseola, is a major disease affecting common bean. Important resistance sources have been identified and characterized: AND 277, BAT 332, Cornell 49-242, MAR-2, and Mexico 54. P. griseola presents high physiological variability. The control of this kind of pathogen requires continuous evaluation, including monitoring and characterization of pathogenic variability, and eventual germplasm introgression of genes in adapted cultivars. Cultivar Ouro Negro is currently being used as an ALS resistance source in Brazil. This work aimed to characterize the ALS resistance gene present in cultivar Ouro Negro in relation to the other five resistance sources. These cultivars were crossed with 'Ouro Negro' (allelism tests) and with susceptible cv. Rudá (inheritance studies) and their segregation patterns were evaluated. The inheritance studies and the allelism tests indicate that 'Ouro Negro' harbors at least one resistance locus which is distinct from those present in the other resistance sources.

Effects of fungicide application and different nitrogen fertilizer levels on yield components of three varieties of common bean Phaseolus vulgaris L.

“…190.S were Sanyang et al 971 intermediate. The resistance of PNG to ALS is in confirmation with other research findings carried out with this variety and others under different ecological conditions (Fontem et al, 2007;Ngueguim et al, 2011;Sanglard et al, 2013). This resistance to ALS has been largely attributed to the genetic makeup (genotypes) of this variety and other local ones.…”

Introgression of resistance to pathogens in common bean lines with the aid of molecular markers

“…Sanglard et al (2007) and Melo et al (2008) also obtained this same result with the Rudá-R line. Molecular characterization of the recurrent parents shows the possibility of monitoring of most of the resistance alleles in the populations under selection, with the exception of lines BRSMG Talismã and VC9.…”

“…The former was not polymorphic for the marker SCARH13, since it also showed amplification for this marker. This result contradicts the result found by Melo et al (2008) in which this cultivar did not show the band in question and corroborates the result of Sanglard et al (2007). The VC9 line showed amplification in reference to the primer SCARY20, which marks the allele Co-4 and, therefore, does not allow the monitoring of this allele in the population arising from this parent.…”

Evaluation of Common Bean (Phaseolus vulgaris L.) Germplasm for Resistance to Angular Leaf Spot Disease [Phaeoisariopsis griseola (Sacc.) Ferraris] under Cold Arid Conditions of Ladakh

“…Genotypes AND 277, MAR-2, Mexico 54, BAT 332 and Cornell 49249 were identified as potential sources of resistance having dominant genes that govern plant resistance to certain races of P. griseola Sartorato et al 2000;Aggarwal et al 2004;Caixeta et al 2005: Pereira et al 2015. Genotype Ouro Negro was reported to have dominant gene that controlled resistance to P. griseola races 63-39 and 31-32 (Sanglard et al 2013). The common bean genotypes G10474 and G1090 were reported to have a single dominant gene conditioning resistance to two P. griseola pathotypes (Mahuku et al 2004 and2011).…”