Latent time characteristic of some species of Cactaceae family cultivated in Peter the Great botanical garden

Collections of living plants of botanical gardens are supported and developed to a greater extent through the acquisition and exchange of living or seed material with colleagues from other gardens, as well as through inter-botanical exchange of reproductive diasporas. It is important to know the period of storage of germination seeds, in order to determine the shelf life of seeds, not to store and not to distribute unimportant seeds. The quality of collected seeds should be evaluated for fulfill these conditions. The success of growing of different plants in the Botanical Gardens depends of the quality of the obtained seeds. The paper presents the characteristics of the fruits and seeds of species from the following genera’s (Cactaceae) – Aylostera, Blossfeldia, Chilita, Cleistocactus, Copiapoa, Coryphantha, Discocactus, Echinocactus, Echinopsis, Eriosyce, Ferocactus, Frailea, Matucana, Mediolobivia, Melocactus, Neochilenia, Neomammillaria, Parodia and Rebutia, which cultivated at the Peter the Great Botanical Gardens of the Komarov Botanical Institute of RAS. The number of seeds in the fruit, the mass of 1000 seeds, laboratory germination (determined by the standard method in Petri dishes) at different shelf life was determined. It has been shown that the freshly harvested seeds of some cacti species germinate stretched over time (up to 60 days). Germination varies from 0 to 100%. The highest germination rate for each species is registered after 2-3 years of storage. Freshly harvested seeds of the bulk of the studied species do not germinate immediately (after 10-15 days), and its performance is lower than that of seeds stored in the laboratory for several years. The results allow us to conclude that the seeds of different types of cacti can be stored for several years without of germination loss, and, therefore, use them for inter-botanical exchange.