The variability of leaf anatomical characteristics of Solanum nigrum L. (Solana-les, Solanaceae) from different habitats

In Europe on the whole as well as in Yugoslavia, the most widespread weed species from the genus Solanum is Solanum nigrum L. Since this species inhabits different habitats, it developed several ways of adaptation to environmental conditions. The influence of ecological factors on plant organism and resulting plant adaptations are most evident in leaf morphology and anatomy. Therefore, the anatomical structure of leaves and leaf epidermal tissue of S. nigrum was analyzed and compared among plants that originated from different habitats, in order to determine leaf structural adaptations. S. nigrum lamina has the mesomorphic structure with some xero-heliomorphic adaptations. The differences in stomata number, number of hairs, thickness of lamina, palisade and spongy tissue, as well as the size of mesophyll cells have been noticed. The highest values for most of the parameters have been recorded for the plants from cultivated soil. Largest variations of the examined characters were found for the leaves from ruderal habitats, where environmental conditions are most variable.