Isozyme and organellar DNA analysis of genetic diversity in naturalaturalised European and Asiatic walnut (Juglans regia L.) populations.

摘要

European stands of Juglans regia were analysed in comparison with Asiatic ones (Caucasus, NW and NE China) by means of nuclear (isoenzyme) and organellar (PCR-RFLP) genetic markers in order to obtain information on the genetic structure, diversity and differentiation of populations at the level of different genomes. The isoenzyme genetic analysis showed that genetic differentiation within European populations was similar to that found in Asiatic populations and close to that found in other broad-leaved cross-pollinated tree species. At the intrapopulation level the artificial propagation of walnut, due to human activities, did not affect genetic differentiation. On the other hand, genetic differentiation between stands was lower in the European groups than in the Asiatic one. This figure can probably be interpreted as resulting from the strong human impact of this species in the European continent. The analysis of ct- and mt-DNA did not reveal any polymorphism.