Germination and seed sprouting pattern of rare plants of Yakutia

Abstract

The article presents results of research work devoted to study germination and sprouting process of 46 rare, endangered and endemic species and subspecies of spontaneous flora of Yakutia. Germination and sprouting patterns were determined in freshly collected seeds (on the day of collection) and after 6 months of storage at room temperature of 23 ± 1 °C. The studies were based on the collection of the spontaneous flora of the Yakutsk Botanical Garden. According to a seed sprouting classification proposed by I.V. Borisova (1996), 10 rare species (IB) are characterized by high germination capacity and fast seed sprouting. The seeds with slow sprouting (II) are represented by 20 taxa, 16 species of which are with the maximum number of the germinated seeds at the beginning of sprouting – IIA. The seeds with fast germination of types IA and IB as well as IIA and high germination are common for taxa, which are decreasing in number and the rarity of which is not caused by their biological features but by external factors. The seeds with the low laboratory germination, primary dormancy of different duration and germinating after ripening and with the zero germination are represented by 16 species (III). Pre-sowing procedures have been suggested in order to derive the latter from the resting condition. After 6 months storage, the pattern of seed germination remains for most species, but it changes for some species, both in the direction of accelerating and decelerating, their laboratory germination capacity can also vary, more often it increases. The problematic seed germination of some rare species with small ranges in the territory of Yakutia suggests that the quality of seeds is one of the factors limiting their wider distribution.