Search

Revegetation emerges as a promising approach to alleviate the adverse impacts of mining residues. However, it is essential to evaluate the characteristics of these materials and select suitable plant species to ensure successful ecosystem restoration. This study aimed to investigate the effects of phosphate-mine residues (MR) on the growth, biochemical properties, and essential oil concentration of Rosmarinus officinalis L., Salvia Officinalis L., Lavandula dentata L., and Origanum majorana L. The results showed that R. officinalis L. appeared to be particularly well-suited to thriving in MR soil. Our finding also revealed that L. dentata L., O. majorana L., and S. officinalis L. grown in MR exhibited significantly lower growth performance (lower shoot length, smaller leaves, and altered root structure) and higher antioxidant activities, with an alterations of photosynthetic pigment composition. They showed a decrease in total chlorophylls when grown on MR (0.295, 0.453, and 0.562 mg g -1 FW, respectively) compared to the control (0.465, 0.807, and 0.808 mg g -1 FW, respectively); however, they produced higher essential oil content (1.8%, 3.06%, and 2.88%, respectively). The outcomes of this study could offer valuable insights for the advancement of revegetation technologies and the utilization of plant products derived from phosphate-mine residues.

Salinity is a severe abiotic problem that has harmful impacts on agriculture. Recently, biostimulants were defined as bioprotectant materials that promote plant growth and improve productivity under various stress conditions. In this study, we investigated the effect of Crataegus oxyacantha extract as a biostimulant on tomato plants (Solanum lycopersicum) grown under salt stress. Concentrations of 20 mg/L, 30 mg/L, and 70 mg/L of C. oxyacantha extract were applied to tomato plants that were grown under salt stress. The results indicated that plants that were treated with C. oxyacantha extract had a higher ability to tolerate salt stress, as demonstrated by a significant (p < 0.05) increase in plant growth and photosynthetic pigment contents, in addition to a significant increase in tomato soluble sugars and amino acids compared to the control plants. In the stressed tomato plants, malondialdehyde increased and then decreased significantly with the different concentrations of C. oxyacantha extract. Furthermore, there was a significant improvement in the antioxidant enzyme activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione S-transferase (GST), and glutathione reductase (GR) in the stressed plants, especially after treatment with 70 mg/L of the extract. Overall, our results suggest that C. oxyacantha extract could be a promising biostimulant for treating tomato plants under salinity stress.