STINGING NETTLE (URTICA DIOICA L.) GROWTH AND MINERAL UPTAKE FROM LEAD-ARSENATE CONTAMINATED ORCHARD SOILS

Growth and mineral uptake was studied in stinging nettle (Urtica dioica L.) grown on lead-arsenate contaminated orchard soils. Six soil samples including a non-orchard control were used. Uniform U. dioica seedlings were transplanted into pots arranged in a completely randomized design and raised under uniform greenhouse conditions. Shoots were harvested at day 26, and shoot (harvest 2) and root portions 50days after transplanting. All samples were oven dried, weighed, and processed for mineral analysis. Elevated arsenic levels in soil did not significantly affect nettle growth except at the highest concentration of 163mg kg(-1). There was arsenic bio-concentration in U. dioica roots and high levels of arsenic and lead in both below- and aboveground tissues. Stinging nettle is a plant of economic importance harvested for food and medicine. Our results show that humans can be exposed to toxic levels of arsenic and lead through contaminated nettle products.