Genetic diversity of wild stone fruit species: specific aspects of ex situ conservation

Abstract

Background. One of the most important tasks faced by the scientists of Krymsk Experiment Breeding Station of VIR is the long-term preservation of the stone fruit gene pools (over 1,000 genotypes of 44 species) collected during plant explorations. It is much more difficult to preserve representatives of the wild flora than cultivars, due to their ecological specialization to specific environments and the need to create conditions for their successful development. This aspect concerns, first of all, such species as Louiseania pedunculata (Pall.) Pachom., L. ulmifolia (Franch.) Pachom., Prunus cocomilia Ten., P. brigantiaca Vill., Armeniaca sibirica (L.) Lam., Padus ssiori (F. Schmidt) C.K. Schneid., and some others.Methods. The studies were carried out in the collection plantations of the field genebank at Krymsk Experiment Breeding Station of VIR according to VIR’s guidelines. Accessions of wild stone fruit species were the objects of the studies.Results. Many years of field research into ex situ conservation of introduced wild species proved the efficiency of stone fruit cultivation in tub culture and a modified technique of dense planting with crown formation according to the “border-hedge” pattern. It takes into account biological characteristics of genotypes shaped in natural areas, the use of own-root or grafted plants on clonal rootstocks of various growth rates depending on their life form (tree or shrub), resistance to biotic and abiotic stressors, soil and terrain requirements, and the tasks posed before researchers. The recommended planting schemes (2.5–4.0 × 0.5–1.0 m) significantly reduce the area occupied by the same number of plants in conventional cultivation patterns and cut down power and labor inputs into technological practices.