DORMANCY AND GERMINATION OF INTRASPECIFIC AND INTERSPEFIC MOUNTAIN ASH HYBRID SEEDS

Abstract

Features of dormancy and germination of interspecific hybrid seeds of Sorbus sibirica, S. aucuparia and S. sambucifolia in comparison with parent species have been studied. The research was performed at the Central Siberian Botanical Garden, Siberian Branch of the Russian Academy of Sciences, using the facilities of the Food Plants Introduction Laboratory. Seeds were produced by artificial hybridization. The intact (fresh, not dried up) seeds were germinated by the technique of continuous stratification at temperature of 1-3°C (34-37°F). Hybridity of seeds was detected by SDS-PAGE and ISSR-PCR. Influence of pollinator on dormancy feature in hybrid seeds of Sorbus sibirica Hedl., S. aucuparia and S. sambucifolia was detected. The hybrid seeds of S. sibirica × S. aucuparia and S. aucuparia × S. sambucifolia inherit depth of dormancy and germination time heterogeneity typical of S. sibirica. Seed germination dynamics of S. sambucifolia ´ S. aucuparia and S. sambucifolia × S. sibirica was similar to S. aucuparia, but dormancy depth and heterogeneity were much lesser than those in seeds of parent species. The hybrid seeds of S. sambucifolia × S. aucuparia, S. sambucifolia × S. sibirica, S. sibirica × S. sambucifolia and S. aucuparia × S. sambucifolia almost completely lose dormancy features, which have been inherited from maternal genotypes. The results obtained are significative of the need to monitor the effect of pollinator in experiments on studying features of seed germination and dormancy in mountain ash as well as in other (introduction, breeding, recreation, etc.) studies, where seed germination is an important stage.