Salt and heavy metal stress responses and metal uptake potentials of some leafy vegetables

Abstract

Abiotic stress conditions caused by increasing anthropogenic activities over the years necessitate using marginal waters in agricultural irrigation and pose a risk to public health by causing salt stress and heavy metal pollution in the soil. The study exposed rocket (Eruca sativa L.), cress (Lepidium sativum L.), and parsley (Petroselinum crispum Mill.) plants to heavy metals (Zn, Cu, Ni, Pb, Cd, and Cr at rates of 300, 140, 75, 300, 3, and 100 mg kg⁻¹, respectively) and salt stress (3, 6, and 9 dS m⁻¹). Both stress conditions affected plant growth negatively. Biomass losses reaching 88% occurred in the rocket, which was determined to be more sensitive to salt stress than heavy metal stress. In parsley, on the other hand, it was determined that the above-ground organs were more affected by salt stress, but the negative effect of heavy metal stress on the roots was higher than salt stress. In cress, the cultivars produced different responses to stress factors. The Zeybek cultivar was more affected by salt stress, and Bahargülü was more affected by heavy metal stress. In general, an increase in macro- and micronutrients was found under stress conditions. In addition, it was determined that the plants were hyper-accumulative in terms of lead absorption and were sorted as cress > parsley > rocket in terms of metal uptake. According to these findings, these plants should be grown taking into account the lead values in the soil, and consumers should be aware that they are a group of vegetables that accumulate lead.