Morphological features of Delphinium sergii Wissjul. leaves in ontogeny

There are represented results of the study on leaf shape and its morphological diversity of the Delphinium sergii Wissjul. which is an endemic species of Eastern Black Sea Coast and was introduced in the culture at the M.M. Gryshko National Botanical Garden NAS of Ukraine. It is found that D. sergii is characterized by heterophylly and morphological variability of leaf blades which is manifested during ontogeny, in process of formation of its vegetative and generative shoots. The correlation of the dissection degree of the leaf blades with their formation and age has been established. More deeply dissected leaves are «older» while with complete laminas are more «younger». During the ontogenesis firstly occurs the complication of a simple lamina in seedlings by its division into segments. And, as a result, along the shoot the complication from lower to middle formations and further simplification of leaf structure in upper formation in generative individuals is observed. Formation of different by shape leaves in individuals of the same age stage as well as of the same age depends from conditions of lighting, soil moisture, crop density, and genetic heterogeneity, and therefore – from morphological plasticity of individuals in different conditions of growth.