Evaluating growth and physiological responses of Moringa peregrina and Moringa oleifera to elevated CO₂ and UV-B radiation in open-top chambers for climate resilience

Abstract

Climate change poses complex and unpredictable challenges to the ecosystems and agricultural systems. Anthropogenic activities have increased CO₂ concentrations in the atmosphere and changes in ultraviolet-B (UV-B) radiation. These environmental changes severely impair crop growth and production of crops, particularly in sensitive species. Therefore, evaluating the combined effects of eCO₂ and UV-B radiation is essential for predicting climate change on crop systems and ecosystem stability. The aim of this experiment was to evaluate the tolerance of two Moringa species (Moringa oleifera and Moringa peregrina) to elevated (eCO₂), UV-B radiation and their combined effects. The results revealed that Moringa oleifera under eCO₂ treatment had higher plant height than Moringa peregrina. On the other hand, the lowest plant height was recorded in both tested species under UV-B radiation treatment. Further, chlorophyll a, chlorophyll b, and carotenoid content in Moringa oleifera were much higher in eCO₂-treated plants than in Moringa peregrina, although UV-B radiation had a significant impact on reducing photosynthetic pigments in both species. The nutrient analysis also revealed that the levels of nitrogen (N), magnesium (Mg), calcium (Ca) and boron (B) in Moringa oleifera were significantly higher than those in Moringa peregrina under eCO₂ treatment. Conversely, the concentrations of potassium (K), iron (Fe), manganese (Mn), copper (Cu), zinc (Zn) and sulfur (S) were found to be greatest in the Moringa peregrina under eCO₂ treatment.