Abstract:
Crop production is seriously threatened by global climate change and recent demands for the growth of crops to
produce bio-fuels. On the other hand, population growth will exert an immense pressure on food demand in the
coming years. By 2050, food production will need to increase by 50% to feed the growing population. The most
feasible option is to increase the crop yield potential through increasing the photosynthetic capacity per leaf area.
Raising the atmospheric C02 concentration from the current concentration of 390 to 550 L C02 L 1 (year 2050 C02
concentration in the atmosphere), caused an increase in photosynthesis by (31%), while photorespiration and
stomatal conductance decreased by ~50% and ~22% respectively. This increase in photosynthesis at elevated C02
will promote a grain yield of up to 45% for some cereal cultivars suggesting that yield enhancement is possible
through increasing photosynthesis.
