Ontogenetic development and maturity of individuals of Polygonatum multiflorum

Development and reproduction, particularly the dynamics of growth and age for reaching generative maturity, are poorly known aspects of the biology of clonal perennial herbs. The aims of this study were to determine the ontogenetic development, age of first sexual reproduction and fertility of plants grown from seeds in experimental sowings of a perennial herb. I hypothesized that individuals of Polygonatum multiflorum (L.) All. (Asparagaceae) require a certain size for clonal growth, and for generative maturity. Hence, the study was conducted for 11 years in an experimental garden as well as natural conditions, and has shown that: (i) each individual formed its first aerial shoot in the second year of development from seed. (ii) Rhizome branching began in the fourth year of growth, and individuals with a branched rhizome had a significantly larger number of rhizome segments and leaves than individuals with unbranched rhizome. (iii) The number of leaves in individuals increased significantly one to two years before they reached generative maturity. (iv) The first flowering shoots appeared at the earliest in the seventh year but most often in the tenth year of development from seeds. Sexual maturity was reached by a small (1-5%) fraction of individuals (seedlings). After eleven years of growth most individuals had a simple architecture of rhizome with few segments, and one aerial vegetative shoot. Individuals which flowered for the first time had always several aerial shoots, and such plants had more segments, aerial shoots and leaves than the vegetative ones. Individuals reached generative maturity and produced fertile seeds at a similar age. Germinability of these seeds was high both in the garden and laboratory raised plants.