Divergência genética entre acessos de açafrão (Curcuma longa L.) utilizando caracteres morfoagronômicos

Abstract

Two experiments were conducted in the experimental area of the Universidade Federal de Goiás for assessing the genetic divergence among 21 genotypes of turmeric cultivation in two years (EI) and 33 genotypes in cultivation of one year (EII) based on multivariate analyses, order to select divergent genotypes and find out the Mara Rosa producers use the same genotype. The accessions came from Goiás, Minas Gerais and São Paulo. The experiments were conducted in the 2001/2003 period (EI) and 2003/2004 (EII) using a randomized block design with four replications. The assessment of EI was based on production descriptors as total wet weight of rhizomes, dry weight and content of curcumin. The assessment of EII was based on shoot descriptors as tiller number, leaf number, leaf area, height and also production descriptors. Data were subjected to analysis of variance and means were compared by the Scott-Knott test at 1% and 5% probability. We used the Mahalanobis distance as the dissimilarity measure, and for groups delineation the method of Tocher. All analyzes were performed using the program GENES. In the analyzes it can be concluded that Mara Rosa farmers did not use the same genotype and there is variability in the selection of genotypes. The evaluated characteristics are strongly correlated, which justifies the use of measures of dissimilarities using the Mahalanobis distance. Multivariate techniques were effective for the study of genetic diversity and separated the accessions into groups. Methods of estimation of genetic diversity in turmeric accessions were equivalent. Curcumin content and dry weight were descriptors that contributed to divergence in EI. In EII were plants number and tillers number. It was found the increase in curcumin levels of after two years of cultivation. By Mahalanobis distances could be indicated the five most productive genotypes for breeding program and divergence genetic analysis showed the genotypes more indicated for hybridizations.