Biological diversity of black medic (Medicago lupulina L.)

Abstract

Black medic is widely spread across all continents in temperate and subtropical zones. The species is moderately demanding to the growing conditions. It has been subdivided into three groups of monocarpic, biennial polycarpic, and perennial polycarpic plants. Those in the first group of monocarpics can be annual, biennial and perennial. They are able of completing the life cycle in one season if conditions are favorable. After the removal of generative shoots, the life cycle of plants is extended until the next season or more, until fruiting is completed. Monocarpics do not form a basal rosette of leaves when immature. They are characterized by the indeterminate growth of generative shoots. The second group includes biennial polycarpics, and the third group consists of perennial polycarpics. All of them (biennial and perennial ones) form a basal rosette of leaves in the immature period. They form generative shoots with a determinant type of growth with a complex inflorescence that consists of two or more inflorescences at the top. Wide distribution of black medick is due to the morphological diversity and plasticity of the life cycle.