Characterisation of genetic variability in an breeding population of Juglans regia L.

Abstract

Genetic structure of a breeding population and three naturalised populations of Juglans regia L., was investigated by means of starch gel electrophoresis for 4 enzyme systems. This study reveals variability preservation in the breeding population of first generation respect to the naturalised populations, since heterocigosity levels in the breeding population (0.197) are higher than in naturalised populations of the same geographic area (0.177). Isozyme electrophoretic technique is emphasised as well as an useful tool in the genotype differentiation of J. regia, and it should be advisable to include in the identification of the breeding population some polymorphic isozyme system, like diaforasa, which improve the resolution of this identification technique. As far as molecular marker election to better study of variability, it has been proved that the diversity values are higher with isozymes (0.202) than RAPDs (0.060), although with RAPDs greater number of individuals has been discriminated. Moreover, the joint use of both markers allow individualised identification of studied genotypes. So, the use of both techniques together is considered important for individual identification in the breeding population process, including selection and certification of clones to protect the obtaining rights of it.