The contemporary plant-soil feedback in legume-cereal intercropping systems

Multispecies cropping systems are increasingly recognized for their potential to sustainably intensify crop production. However, there is a paucity of theories that effectively describe the intra- and interspecific interactions among plants growing contemporarily adjacent to each other. This literature review employs legume-cereal intercropping systems as a case study to propose an extension of the “traditional” plant-soil feedback theory that could effectively encompass contemporary effects. We therefore defined this concept as the “Contemporary Plant-Soil Feedback” (CPSF). The shifts in soil nutrient, carbon, and microbial dynamics were investigated. The analysis indicated that intercropping legumes with cereals can consistently enhance nitrogen availability for the cereal, thereby reducing losses. Phosphorous availability was also often increased. Nevertheless, the shifts in carbon cycling were context-dependent. These changes were reflected in microbial community functionality. Microbial biodiversity, however, was not identified as a primary driver of the CPSF effect in this cropping system. Although intercropping had a consistent influence over the phylogenetic assemblage of microbial communities, effects were deemed to be related to the edaphic factors. Overall, this framework provides a new perspective for interpreting plant-soil-microbial dynamics in agricultural systems.