Stevia rebaudiana under a CO2 Enrichment Atmosphere: Can CO2 Enrichment Overcome Stomatic, Mesophilic and Biochemical Barriers That Limit Photosynthesis?

Abstract

Due to the desire to live a healthier lifestyle, the search for nonglycosidic sweeteners has increased stevioside production in recent years. The main goal of this study was to demonstrate that S. rebaudiana grown in a CO2-enriched environment can overcome stomatic, mesophilic and biochemical barriers that limit photosynthesis (AN). We show that in an environment with a CO2-enriched atmosphere (800 and 1200 µmol CO2 mol−1), the genotype 16 (G16) shows an increase of 17.5% in AN and 36.2% in stomatal conductance in plants grown in 800 µmol CO2 mol−1 when compared to non-enriched plants. In conjunction with this issue, the plants show an efficient mechanism of dissipating excess energy captured by the photosystems. Photosystem II efficiency was increased at 1200 µmol CO2 mol−1 when compared to non-enriched plants, both in genotype 4 (25.4%) and G16 (211%). In addition, a high activity of Calvin–Benson enzymes, a high production of sugars and an enhanced production of steviosides were combined with high horticultural yield. Both genotypes (G4 and G16) showed excellent physiological indicators, with high superiority in G16. Thus, our study has demonstrated that S. rebaudiana could adapt to global climate change scenarios with higher temperatures caused by higher atmospheric CO2.

Net Photosynthesis and Biomass Production in Stevia, Eggplant, and Cowpea Can Be Improved by Fertilization with Cyanobacteria (Limnospira maxima)

“…A smaller LS is expected in plants with more open stomata, allowing for greater gas exchange, while a higher LS denotes stomatal limitations. In general, an intermediate value is given as 0.5, which would be the threshold between stomatal and nonstomatal limitation [29]. In this study, we showed that, with the exceptions of S. rebaudiana, V. unguiculata and S. melongena presented significantly lower LS values when compared to the control, indirectly meaning that L. maxima caused a significant stomatal opening.…”

Role of Arbuscular Mycorrhizal Fungi in Regulating Growth, Enhancing Productivity, and Potentially Influencing Ecosystems under Abiotic and Biotic Stresses

“…The advanced nutrition of phosphorous and mycorrhizal colonization by AMF can move plants' resilience to drought by changing cell membrane permeability to water [263]. Below situations of dry season pressure, AMF exerts its effect on developing the happening amount and decreasing stomata opposition or changing the equilibrium of plant chemicals [303]. The improvement in leaf turgor and water capacity caused by AMF inoculation also enhances root length and intensity.…”