Morphological Variability and Biochemical Parameters of Leaves in Cenopopulations of Aegopodium podagraria L. (Apiаceae, Apiales) under Various Levels of Soil Contamination by Heavy Metals

Resumo

Abstract—The morphological variability, lipid peroxidation (LPO) rate, and photosynthetic pigment content in leaves of Aegopodium podagraria L. were studied in four cenopopulations of urban ecosystems on soils differently contaminated by heavy metals (HMs): Pb, Zn, Cu, and Cr. The increased HM content in soil causes a drop in the terminal leaflet size, in the mean number of phens (various variants of leaf shape), and in the chlorophyll b content in leaves. On the contrary, the percentage of rare phens increases. Parallel to this, the LPO rate decreases, which is not typical for plants under stress conditions. The level of chlorophyll a and carotinoids drops under moderate contamination and becomes normal at the highest one. The data obtained testify that the morphological and biochemical parameters of goutweed leaves differently characterize the status of this plant species under an increase in the level of soil contamination by HMs. Such conditions result in the impoverishment of the phenofund of A. podagraria cenopopulations and in the domination of plants with smaller leaves. Nevertheless, their LPO rate and the content of some pigments may remain close to normal. The results of our study show that A. podagraria is a species that is able to maintain biochemical homeostasis under the conditions of soil contamination by heavy metals. Thus, contrary to the biochemical parameters studied, the morphological features more accurately characterize the adverse changes in cenopopulations of goutweed, which is important for the bioindication of ecosystems under anthropogenic contamination.