Genetic divergence among garlic accessions grown in different environments in the state of São Paulo, Brazil

Divergência genética entre acessos de alho avaliados em ambientes distintos no estado de São Paulo, Brasil

ABSTRACT

The objective of this study was to assess the genetic variability of 63 garlic accessions grown in two environments in the state of São Paulo, Brazil. A randomized block design with replications was used. Agromorphological evaluations were conducted based on descriptors defined by the International Plant Genetic Resources Institute (IPGRI), currently Bioversity International, encompassing 18 characteristics. The obtained data consisted of the mode of each variable and genetic distances from the complement arithmetic of the Jaccard coefficient. Cluster analysis was carried out using Tocher optimization and UPGMA methods; Mantel test was used to assess the correlation of genetic distances between locations. Garlic accessions exhibited genetic diversity for the studied qualitative variables. Correlations between distances of the evaluated accessions were found in both locations, although of low magnitude. Garlic characteristics vary according to growth environment, indicating divergence among accessions. This may be attributed to the plasticity of the species and genotype-environment interaction factors. Phenotypic variability of garlic germplasm observed in a particular environment cannot be extrapolated to other locations.

Keywords
Allium sativum L; Cluster analysis; Genetic variation; Multivariate analysis