Genetic diversity and promising crosses indication in lima bean (Phaseolus lunatus) accessions

Resumo

Lima bean is a source of income for the rural population of Northeast Brazil because people purchase and consume the imature and mature beans. In this region, all of the germplasms used by farmers come from their own crops or they trade between rural communities. Understanding the genetic diversity of the lima bean germplasm provides important information for both managing germplasm banks and genetic conservation. In this study, we aimed to estimate the genetic diversity between 24 lima bean accessions from the Active GermplasmBank (AGB) at the Universidade Federal do Piauí (UFPI) based on morphoagronomic descriptors. The experiment was conducted under field conditions in lattice design with four replications and ten plants per plot, from February to August 2009. Seven qualitative and six quantitative descriptors were used. Four groups were created for quantitative traits using the Tocher and Unweighted Pair Group Method with Arithmetic Mean (UPGMA) methods, while qualitative traits were divided into three groups using the Tocher method and into six groups using UPGMA. The trait that contributed the most to genetic diversity (35.23%) was pod width. UFPI-220 produced a large number of pods per plant, an important trait for identifying potentially productive accessions. We expect that beneficial combinations can be made between UFPI-220 x UFPI-468 due to both the high level of dissimilarity and the average performance of these accessions.