Bean production in fragile, unfavorable of marginal environments : overview and issues | [Produccion de frijol en ambientes fragiles, desfavorables o marginales : antecedentes y resultados]

conduite de la culture crop management ecosistema ecosystems environment environmental degradation environnement exploitation agricole marginale explotaciones marginales fertilidad del suelo fitomejoramiento gestion des ressources highlands manejo del cultivo marginal farms medio ambiente phaseolus vulgaris plant breeding production recherche research resource management sloping land socioeconomic environment soil fertility sostenibilidad sustainability terre en pente terreno en declive