Leaf functional traits in maize in intercropping

Yield gains in intercropping are greatest in systems with maize. We studied functional trait plasticity in maize leaves in intercrops to assess the possible contribution to crop carbon accumulation. We compared leaves at different growth stages and positions on the maize plant in sole crops and intercrops. Responses of maize leaves to shading from faba bean or wheat as companion species resulted in thinner leaves with a lower nitrogen content per unit leaf area and a lower leaf nitrogen concentration. Photosynthesis was reduced in these thinner leaves with lower nitrogen content. The changes in leaf functional traits were especially apparent in border row maize plants. During late maize development, the photosynthetic capacity of maize leaves in intercrops did not recover from earlier competition. The results show that plasticity in leaf functional traits in intercropped maize in response to wheat and faba bean reduces the potential for crop carbon accumulation.