An experimental study on the effects copper and lead on the seedlings of some economically important vegetable species

Abstract

Bioaccumulation of toxic heavy metals in vegetables is closely related to the problems of safety concerns as they negatively affect plants in particular those consumed by the humans. Among the food systems the vegetables are the most noticeable foods affected by environmental pollution. Vegetables can take up the metals like copper and lead and store them in excessive levels. Keeping this in view this investigation was undertaken to study the effect of copper and lead concentrations (20, 40, 80, 160, 240, 320, 640, and 1280 µM) and assess their toxic affects on germination and seedling growth at early stages of eight vegetable cultivars; kidney bean, peas, black-eyed bean, artichoke, kale, lettuce, rocket and radish. The results were evaluated by multivariate analysis of variance and Pearson correlation statistical analysis. Our results indicate that the seeds of the vegetables studied by us are generally tolerant to both copper as well lead, except higher concentration exposures which showed no improvement when applied to artichoke (for Cu 1280 µM) and lettuce seeds (Cu 1280 µM; Pb 1280 µM). An application of copper and lead ended up with a decrease in barium, calcium, iron, magnesium, manganese, sodium and zinc content in all seedlings studied. In all vegetables exposed to copper and lead a promotion in copper and lead accumulation was recorded. There was a decrease in nutrient element intake which interrupted the mineral element uptake in the seedlings.