Avaliação da resistência à antracnose em etnovariedades de Phaseolus lunatus L.

Abstract

Sources of disease resistance can be getting from in situ or ex situ genetic resources. Between the in situ genetic resources exploited for quest of resistance are native varieties. Native broad bean varieties from the Northeast were addressed in an anthracnose resistance study. The genetic and cultural characterization of allergies was characterized and evaluated for anthracnose resistance. The work carried out a survey and collect of varieties in crops, free fair and public market, being determined genetic diversity and the resistance to Colletotrichum truncatum. Previously developed questionnaires were applied to interview producers and middlemen. The collective discourse was constructed and consolidated information helped to distinguish ethnovarieties. Genetic diversity was determined based on 52 morphoagronomic characters, 32 being qualitative and 20 quantitative for categorization and cluster analysis. The molecular analysis addressed the genome (Internal Transcribed Space, ITS) and was made phylogenetic grouping. In vitro and in vivo inoculation assays are characterized by a resistance and susceptibility reaction to two isolates. Complementarily, the spontaneous symbiotic efficiency was evaluated. The consolidated discourse portrays a cultivation of family broad bean, rudimentary and traditional. Maintained for five decades by mostly female producers and over 50 years old. The quantitative traits that contributed most to genetic diversity were length and width of seeds and pods, corroborating the grouping of ethnovarieties in the phylogenetic tree in the Mesoamerican genetic pool I and II (MI and MII). In the in vivo assay it was verified that it is a resistance response to isolation ICT12 is more frequent in the ethnovarieties grouped in the MI genetic pool. The resistance to ICT16 isolation predominates in the ethnovarieties gathered in the genetic pool MII. Alagoanas varieties represent the typical diversity of the Mesoamerican gene pool, distinguishing also in the composition of probable alleles that regulate the response to C. truncatum. Thus, obtaining varieties with greater resistance requires crossing between resistant varieties that represent the two genetic groups. Symbiotic efficiency presented inconclusive results.