Caracterização morfológica de acessos de inhame oriundos dos municípios produtores de Alagoas e Sergipe

Abstract

The yam belongs to the Dioscoreaceae family and to the Dioscorea genus, which has more than 600 species, of which 14 have their commercially used rhizophores. The Northeast region of Brazil concentrates the majority of the yam crops, mainly in areas of family agriculture, in which it plays an important socio-cultural and economic role. There is a predominance of the species Dioscorea cayenensis Lam. in the cultivated areas of this region, however, little is known about its genetic diversity. Thus, the rescue and knowledge of the genetic variability of the species plays an important role, contributing to the development of new disease resistant genotypes and agronomic characteristics that meet the needs of both producers and the consumer market. In this way, this work aimed to characterize yam accesses from different producing regions of the States of Alagoas and Sergipe, in order to verify the level of genetic diversity present in these regions and a survey about the distribution and local nomenclature of accesses. The access storage, multiplication and morphological characterization was performed at the Research Execution Unit (UEP), Embrapa Tabuleiros Costeiros, in the municipality of Rio Largo, AL. We used 23 accessions represented by the seed rhizophores, in which they were multiplied and characterized, to compose the Germplasm Bank. The characterization of the yam accesses was performed individually in the plants according to the key proposed by the IPGRI / IITA for species of Dioscorea, evaluating 14 characters, being five observations realized in the stem and nine related to the leaves of the yam plants. The data were submitted to analysis, using descriptive statistics and genetic divergence using the Tocher grouping method using the Genes Program. Based on the cluster analysis, we can observe the formation of seven distinct groups, with group I composed of 13 accessions. Although accesses showed a similar morphological phenotype, different popular names were observed by the producers of the study regions. The morphological descriptor stem diameter presented a greater contribution to the differentiation of the accessions. In spite of the variability detected, the current situation of the materials used by farmers in Alagoas and Sergipe is worrying, since several types of yams that were previously used are no longer found.