Growth and photosynthesis responses of Rosmarinus officinalis L. to heavy metals at Bougrine mine

Abstract

Heavy metals pollution is considered as one of the most dangerous environmental problems in agricultural soil, particularly neighboring mining sites. Phytoremediation based on green plants use seems to be an interesting biological solution to detoxify these soils. This study focuses especially on heavy metals effects on Rosmarinus officinalis L. morphological and growth parameters. The site of our research is “Bougrine” mine which represents different zinc, lead and cadmium amounts by geological layers. In opposite to amounts obtained by previous studies made for mining exploration, we thought that zinc content was more important at transition zone than Cenomanian Turonian level. Nevertheless, this element is not the most determinant in plant growth and its morphological parameters. Moreover, R. officinalisL. volume and vigor decreased when soil’s heavy metals content increases. However, this reduction is more related to soil lead content. Despite this decrease, we do not observe any visual phytotoxicity symptom. This aromatic and medicinal species, belonging to Lamiaceae family, could be used as alternative crops in polluted soils.   Key words: Rosmarinus officinalis L., zinc, lead, growth, photosynthesis, “Bougrine” mine.