Water scarcity, exacerbated by global warming and climate change, significantly limits plant growth, productivity, and quality. Given the medicinal and economic value of mint (Mentha spp.) and the importance of water use management for plant production, this study assessed the potential of zeolite to alleviate drought stress in mint cultivation.
The study was conducted as a factorial experiment arranged in a randomized complete block design with three replications. The experimental factors consisted of two mint species (peppermint and spearmint), three treatments of zeolite (0, 20, and 40 g kg-1 soil), and three levels of irrigation at 40%, 70%, and 100% of field capacity (FC).
Results showed that under severe water deficit, in 40% FC, plant height, leaf number, aerial dry weight, chlorophyll, carotenoid, and potassium concentrations were significantly reduced in both species. In contrast, drought stress increased levels of osmoprotectants and stress-related metabolites, including soluble sugars, proline, anthocyanins, phenolic compounds, flavonoids, and antioxidative defense, including guaiacol peroxidase (GPX) and ascorbate peroxidase (APX) enzymes.
Zeolite application at both 20 and 40 g kg-1 soil improved plant growth parameters, chlorophyll content, proline accumulation, sugar and phenolic compound levels, antioxidant enzyme activities, and mineral content (particularly potassium and calcium) under water-limited conditions. Under severe drought (40% FC), zeolite efficiency varied by species: 40 g kg-1 was most effective in spearmint, whereas 20 g kg-1 was optimal for proline accumulation in peppermint.
These findings demonstrate that the application of zeolite is an effective strategy for enhancing physiological performance and drought tolerance in mint species.
