Question

Is maize a C3 or C4 plant?

Answer 1

C₃ plants:

1. Plants that follow the C₃ pathway are C₃ plants.
2. In these, CO2 is fixed into a compound containing three carbon atoms.
3. The key enzyme is RuBisCo.
4. Examples - wheat, rye, and orchardgrass.

C₄ plants:

1. Plants that follow the C₄ pathway are C₄ plants.
2. Oxaloacetic acid (OAA), a 4-carbon compound is the first stable product of carbon fixation in such plants.
3. The key enzyme is phosphoenolpyruvate (PEP) carboxylase.
4. Examples are maize, sorghum, and sugarcane.

Maize as a C4 plant:

1. Maize is a C₄ plant as it uses the C₄ pathway, also called the hatch slack pathway for carbon fixation during photosynthesis.
2. Being a C₄ plant, it has a higher photosynthesis efficiency than C₃ plants, which is increased by reducing photorespiration.
3. It has special leaf anatomy called Kranz anatomy to tolerate high temperatures - a characteristic of C₄ plants.