Résumé:
The needs of plants in trace elements fall within intervals between a threshold of deficiency and a threshold of toxicity. Plants also capture trace elements in their environment without a known metabolic function (for example Cd, Hg, Pb, As, etc.) and therefore considered non-essential.
Foods of plant origin contribute to the impregnation of animals and humans with these trace elements. The absorption of lead, its accumulation in the edible parts of crops, and its transport through the food chain are currently the subject of much research. Our study was undertaken with the aim of determining the effects of four doses of lead nitrate ((Pb (No3) 2) at different doses (0.03 g / l and 0.3g / l and 3.3g / l) on some physiological parameters of germination (percentage of germination and mean time of germination. The results obtained show that lead has a depressive effect on the germination of the tomato Lycopersicum esculentum Mill. And the germination rate.
