Uso de un vivero móvil para obtener patrones de virulencia de la roya del frijol común.

Abstract

As new sources of resistance genes areidentified to rust caused by Uromyces appendiculatus, weneed to know if these genes or others incorporated in the beangermplasm will become susceptible to the pathogen when theresistant varieties are widely grown. We have used a mobilenursery of bean lines/varieties with different rust resistancegenes to answer this question. This nursery, composed of sixday-old bean plants, is placed in a rusted bean field for two tothree hours, misted for 15 hours in a controlled environmentand incubated in a screened house for eight to ten days.Readings for rust uredinia (pustule) size on the plant leavesare then recorded. Data on disease reaction can be used toevaluate the pathogen virulence and predict gene deploymentpathotypes by inoculation in the greenhouse and allowsresults to be known during the growing season as opposed toa few months later. The mobile nursery concept may beespecially useful in countries where greenhouses are rare andmay be used in other crop-pathogen systems.