BIOMORPHOLOGY OF ONTOGENETIC PERIODS OF CHRYSANTHEMUM × HORTORUM REPRESENTATIVES IN THE RIGHT-BANK FOREST-STEPPE OF UKRAINE

The studies of the ontogenesis of plants of the genus Chrysanthemum L., namely Chrysanthemum × hortorum sp., ′Gusi lebedi′ and 'Nova era' had been conducted in the conditions of the Right-Bank Forest-Steppe of Ukraine. The aim of the research was to clarify the morphological characteristics of Ch. × hortorum plants in ontogenesis and to establish the duration of the age periods of plants in the conditions of introduction. The description of age periods was carried out according to the methods of T. Rabotnov, I. Ignatieva and the ontogenetic atlas; the description of seeds was made according to the recommendations of S. Artyushenko to co-authors. Morphological features of plants of various ontogenetic periods were given in accordance with atlases on descriptive morphology of higher plants and an illustrated reference book on the morphology of flower plants edited by S. Zyman et al. Phenological observations were made according to the "Methods of phenological observations in Botanical Gardens of the USSR", and statistical processing of materials was carried out using the Microsoft Excel computer program (2007). It is stated that the studied plants undergo all periods of ontogenetic development under the conditions of introduction. The duration of these periods was given and the morphological characteristics of plants in each of them were revealed. The most critical period of growth and development of the studied plants was the virginal one.