| Abstract |
In the context of climate change, crop growth and yields in arid and semi-arid regions are particularly vulnerable to environmental conditions, such as the availability of irrigation water. Organic amendments, including compost and biochar, could enhance plant growth and resilience to drought stress. In this regard, this study aimed to evaluate the effects of compost and biochar, either individually or in combination, on the morphophysiological, biochemical, and molecular responses of barley plants under drought stress conditions. Eight treatments were included: control (CK), biochar (B), compost (C), biochar and compost (CB), drought stress (D), drought and biochar (DB), drought and compost (DC), and drought and biochar and compost (DCB). Overall, the application of amendments, whether separately or combined, alleviated the negative effects of drought on agronomic parameters and reduced the antioxidant activity of superoxide dismutase (SOD), ascorbate peroxidase (APX), and guaiacol peroxidase (GPOX), except for catalase (CAT). The combined application of compost and biochar increased proline and malondialdehyde (MDA) concentrations while decreasing soluble sugars levels. Furthermore, the application of amendments, whether individually or in combination, downregulated oxidative stress-related genes (HvSOD, HvAPX, and HvCAT), while upregulating key transcription factors (HvAP2/ERF and HvDREB) and functional genes involved in proline biosynthesis (HvP5CS) and water transport (HvPIP) compared to drought stress alone. Interestingly, the combined application of biochar and compost often resulted in a more moderated molecular response than when applied separately, suggesting a synergistic effect that alleviates the impact of drought stress even further. These findings suggest that organic amendments such as biochar and compost, particularly when applied together, can enhance plant tolerance to drought stress. This improvement is accompanied by moderated activation of stress-related responses, which may conduce to a reduced metabolic burden. |
| Authors |
Ghouili, E., Muhovski, Y., Hogue, R., Nefissi, R., Abdelkrim, S., Li, Z., Souissi, F., Jebara, S., Jebara, M., Abid, G. |
