Reproduction of tropical water lilies

The study of coastal and aquatic tropical flora as part of the conservation of world biodiversity is the main purpose of research in botanical gardens. Conservation of plant collections involves a continuous process of plant reproduction. This means searching for ways of reproduction that are most effective for a particular group of plants and optimal timing of obtaining adult specimens. Generally accepted methods for seed (T. A. Rabotnov) and vegetative reproduction were used; for Nymphaea x daubeniana (viviparous water lily) was used the Sean Stevenson method. During 2017-2020 in the Stavropol Botanical Garden was conducted an experiment to study the reproduction of tropical water lilies in protected ground conditions. An artificial pond with a water mirror area of 85 m 2 is located in a greenhouse, heated from October to April. Cross-pollination occurs during the mass flowering period (June-July, with illumination up to 93.5•10 3 kilolux), seed maturation occurs within 58±4 days, and seedlings bloom in 7-8 months. The moderate correlation was established between the soil composition and the intensity of flowering (p < 0.4) and the formation of nodules (p < 0.4). The absence or short flowering of water lily varieties and the mass of nodules (150-300 g) contributes to the formation of more planting material (up to 12 or more pieces). The vegetation period for 99% of the studied plants is 1478±26 days, for the species Nymphaea gigantea it is 887±15 days. Regardless of the species and variety of tropical water lilies, reproduction by daughter nodules formed at the base of the main tuber occurs throughout the growing season.