Environmental factors including climate factors and soil parameters affect growth, physiological processes and production of primary and secondary metabolites in plants. In addition, the responses of plants are widely varied to environmental factors. In the current study the impacts of rainfall, temperature and several soil factors such as soil texture, pH, electrical conductivity, organic matter, organic carbon, calcium carbonate and soil elements on nutrient elements, antioxidative compounds, activity, and isoenzymes patterns of peroxidase and superoxide dismutase in Stachys byzantina were investigated. S. byzantina as a valuable medicinal species was collected from three regions in the north of Iran with different altitudes and ecological conditions. The results showed that the content of nutrient elements (phosphorus, sodium, potassium, calcium), anti-oxidative compounds (phenols, flavonol, flavonoids, and anthocyanin) as well as the activity of peroxidase and superoxide dismutase enzymes along with intensity of their isoenzymes bands were positively correlated with temperature and rainfall, however, almost not correlated with soil parameters. Furthermore, the higher density of S. byzantina in the region with lower temperature and rainfall indicated greater adaptability of the plant in higher altitude areas, which is consistent with a decrease in the antioxidant compounds and activity of oxidative enzymes.
