Efeito da exposição e acumulação de elementos potencialmente tóxicos e salinidade em alface (Lactuca sativa)
2012
Lamas, Mariana Beirão da Cunha | Martins, Maria Luísa Louro | Mourato, Miguel Barbosa
Mestrado em Engenharia Alimentar - Instituto Superior de Agronomia
显示更多 [+] 显示较少 [-]In this work the response of lettuce (Lactuca sativa) to oxidative stress induced by potentially toxic elements (PTE) and NaCl was evaluated. In the germination and growth assays Cd, As, Cu, Mn, Zn (0-500 μM) and NaCl (0-500 mM) was applied separately for assessing the germination rate and growth for 2 weeks. The germination rate was affected only by Cu, Zn and NaCl. Biomass and tolerance index were affected at the higher concentrations of all PTE and NaCl. In irrigation assays, solutions containing Cd, As, Cu and NaCl were applied separately. The number of leaves, biomass, dry matter content, chlorophyll content mineral composition were determined. The application of Cd and NaCl led to a decrease in the number of leaves and in all experiments there was a significant reduction in biomass and chlorophyll in contaminated plants. The application of NaCl led to an increase in dry matter content and the plants were visibly affected. There was accumulation of PTE and of Na in all the plants growing in the contaminated medium, exceeding legal limits for Cd and As, so their intake can be a hazard to human health.
显示更多 [+] 显示较少 [-]