Light capture and water use in intercrops

Intercropping of wheat and maize is widespread in northern China. This system is more productive than single crops of either species. It is hypothesized that enhanced radiation capture is the key mechanism for this intercrop overyielding. In part, this enhancement is related to the relay aspect of the system: wheat is sown before maize, and maize keeps growing after wheat harvest. Thus, the intercrop system can capture more light. Understanding light capture in intercrops is complex, however. Plants in the intercrops respond to shading by their neighbours, resulting in differences in morphogenesis and growth among plants of the same species growing at different densities or different positions in an intercrop. Here, we adopt a functional-structural plant modelling approach to quantitatively characterize these plant responses and build modelling tools for designing crop systems that maximize light interception and yield. These model tools can also be used to calculate the transpiration demand and optimize water use in the semi-arid conditions of North China.

This project started in October 2010 and is currently running.