Crop Enhancement of Cucumber Plants under Heat Stress by Shungite Carbon

Heat stress negatively impacts plant growth and yield. The effects of carbon materials on plants in response to abiotic stress and antioxidant activity are poorly understood. In this study, we propose a new method for improving cucumber (Cucumis sativus L.) heat tolerance using a natural carbon material, shungite, which can be easily mixed into any soil. We analyzed the phenotype and physiological changes in cucumber plants maintained at 35 °C or 40 °C for 1 week. Our results show that shungite-treated cucumber plants had a healthier phenotype, exhibiting dark green leaves, compared to the plants in the control soil group.

Furthermore, in the shungite-treated plants, the leaf’s monodehydroascorbate content (a marker of oxidative damage) was 34% lower than that in the control group. In addition, scavengers against reactive oxygen species, such as superoxide dismutase, catalase, and peroxidase, were significantly upregulated. These results indicate that the successive pre-treatment of soil with a low-cost natural carbon material can improve cucumber plants’ tolerance to heat stress and the corresponding antioxidant activity.