Can R/FR signaling in intercropping systems regulate root system development?

The canopies of intercropping systems typically consist of crop species of different heights. This heterogeneous distribution of the canopy results in patterns of light capture (photosynthetically active radiation, PAR) and light signaling (red to far-red ratio, R:FR) different to sole crops, which are much more uniform. R/FR ratio is used by plants as an indicator of plant proximity. Low R/FR ratio induces plastic responses in shoot and root system development.


Even though we know a lot about aboveground responses to shading signals, how plant use this light signal received by photoreceptors to regulate their development belowground, and what this means for plant performance, is rarely studied. There are indications that root system development is stimulated at a low R/FR ratio, but it is unclear to which extent this could play a role in the plant-plant interactions in intercropping systems. This shoot to root communication might help plants coordinate resource partitioning under interspecific competition in intercropping systems, and therefore play an important part in determining intercrop performance benefits.

Research aim

This study aims to understand if the difference of light conditions in the mixed stand (intercropping) and mono stand (sole crop) will trigger altered root system development. The research on interactions between above- and belowground plant–plant signaling is will improve our understanding of the mechanisms of interactions in intercropping.

Types of work

We offer the interested MSc student the opportunity to participate in an experiment in the context of a PhD project on intercropping. The wheat/faba bean mixtures will be grown in the greenhouse at Unifarm under altered light conditions. Shoot and root traits will be observed during the vegetative period. Roots will be scanned and analyzed to quantify root architecture and morphology.