Anthracene-Induced Alterations in Liverwort Architecture In Vitro: Potential for Bioindication of Environmental Pollution

Abstract

Polycyclic aromatic hydrocarbons (PAHs) are widespread globally, primarily due to longterm anthropogenic pollution sources. Since PAHs tend to accumulate in soil sediments, liverwort plants, such as Lunularia cruciata, are susceptible to their adverse effects, making them good models for bioindicators. The aim of this study was to probe the impact of anthracene, a three-ring linear PAH, on the growth parameters of L. cruciata and the relationship established with the internalization of the pollutant throughout the phenology of the plant. Intrinsic plant responses, isolated from external factors, were assessed in vitro. L. cruciata absorbed anthracene from the culture medium, and its bioaccumulation was monitored throughout the entire process, from the gemma germination stage to the development of the adult plant, over a total period of 60 days. Consequently, plants exposed to concentrations higher than 50 µM anthracene, decreased the growth area of the thallus, the biomass and number of tips. Moreover, anthracene also impinged on plant symmetry. This concentration represented the maximum limit of bioaccumulation in the tissues. This study provides the first evidence that architectural variables in liverwort plants are suitable parameters for their use as bioindicators of PAHs.