phosphorus are limiting crop growth. Additional Free-Air Carbon dioxide Enrichment  experiments are needed in the tropics, particularly on the African continent, to better understand the impacts of increased CO2 concentrations on the productivity of crops and cultivars grown in Africa under additional temperature impacts and water and nutrient limitations . Warming and elevated CO2 may also change the nutritional content of some crops. By 2050 under RCP8.5 , overall wheat yields and grain protein content may decrease by 10% and 15%, respectively, in north and east Africa, and by over 15% in southern Africa . See Chapter 5 for more details on CO2 impacts and uncertainties.
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report