RESUMEN
Widely spread in the tropics, yams were introduced into Brazil during the colonial period and are currently grown throughout the country. Despite its importance as a pharmacological and food source, there is a lack of studies describing how and where this tuber is grown in Brazil. The aim of this study was to provide an overview of the cultivation and distribution of Dioscorea alata in different Brazilian regions. A total of 63 farmers were visited in different municipalities and communities in four regions in the country: South, Southeast, Northeast and Midwest. Semi-structured interviews were conducted to collect socio-economic, use, management and diversity data for this crop. The majority of interviewers were men, married, with children, using retirement benefits and agriculture as income and family labour as the main support in the yam cultivation. A wide distribution of this species was found, with the occurrence of D. alata in the four sampled regions. A variety of vernacular names for this species was collected, differing according to the region where it is cultivated. Most farmers cultivate yams in fields, however an increased usage of home gardens for the cultivation of this tuber was found. Also, most farmers cultivate yams in association with other crops in areas of different sizes and slash and burn practices, although mostly disappearing, are still being used by many farmers. The results of this study provide more concrete data on the distribution and diversity of this important crop.
Asunto(s)
Agricultura/métodos , Biodiversidad , Productos Agrícolas/clasificación , Dioscorea/clasificación , Adulto , Anciano , Anciano de 80 o más Años , Agricultura/estadística & datos numéricos , Brasil , Femenino , Geografía , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Factores Socioeconómicos , Adulto JovenRESUMEN
Dioscorea cayenensis and Dioscorea rotundata are among the most important yam species for the humid and sub-humid tropics. We isolated nine polymorphic microsatellite markers using a microsatellite-enriched genomic library technique. The nine primer pairs were validated in 22 D. cayenensis accessions, and were tested for transferability in 26 D. rotundata accessions. The number of bands ranged from 2 to 4, with a mean of 3.11. D. cayenensis gave primer polymorphism information content values ranging from 0.37 to 0.62, while for D. rotundata the values ranged from 0.15 to 0.66. The D parameter in D. cayenensis ranged from 0.14 to 0.40, while in D. rotundata it ranged from 0.05 to 0.34. These SSR markers will be useful to characterize genetic diversity in D. cayenensis and D. rotundata accessions.