Background Global climate is changing more rapidly than ever, threatening plant growth and productivity while exerting considerable direct and indirect effects on the quality and quantity of plant nutrients. Scope This review focuses on the global impact of climate change on the nutritional value of plant foods. It showcases the existing evidence linking the effects of climate change factors on crop nutrition and the concentration of nutrients in edible plant parts. It focuses on the effect of elevated CO2 (eCO2), elevated temperature (eT), salinity, waterlogging and drought stresses, and what is known regarding their direct and indirect influence on nutrient availability. Furthermore, it provides possible strategies to preserve the nutritional composition of plant foods under changing climates. Conclusions Climate change has an impact on the accumulation of minerals and protein in crop plants, with eCO2 being the underlying factor of most of the reported changes. The effects are clearly dependent on the type, intensity and duration of the imposed stress, plant genotype and developmental stage. Strong interactions (both positive and negative) can be found between individual climatic factors and soil availability of nitrogen (N), potassium (K), iron (Fe) and phosphorous (P). The development of future interventions to ensure that the world's population has access to plentiful, safe and nutritious food may need to rely on breeding for nutrients under the context of climate change, including legumes in cropping systems, better farm management practices and utilization of microbial inoculants that enhance nutrient availability.
Iron deficiency chlorosis (IDC) is an abiotic stress often experienced by soybean, owing to the low solubility of iron in alkaline soils. Here, soybean lines with contrasting Fe efficiencies were analyzed to test the hypothesis that the Fe efficiency trait is linked to antioxidative stress signaling via proper management of tissue Fe accumulation and transport, which in turn influences the regulation of heme and non heme containing enzymes involved in Fe uptake and ROS scavenging. Inefficient plants displayed higher oxidative stress and lower ferric reductase activity, whereas root and leaf catalase activity were nine-fold and three-fold higher, respectively. Efficient plants do not activate their antioxidant system because there is no formation of ROS under iron deficiency; while inefficient plants are not able to deal with ROS produced under iron deficiency because ascorbate peroxidase and superoxide dismutase are not activated because of the lack of iron as a cofactor, and of heme as a constituent of those enzymes. Superoxide dismutase and peroxidase isoenzymatic regulation may play a determinant role: 10 superoxide dismutase isoenzymes were observed in both cultivars, but iron superoxide dismutase activity was only detected in efficient plants; 15 peroxidase isoenzymes were observed in the roots and trifoliate leaves of efficient and inefficient cultivars and peroxidase activity levels were only increased in roots of efficient plants.