Phosphorus (P), iron (Fe) and zinc (Zn) are essential elements for plant growth and development but their availability in soil is often limited.
Xue et al. review the processes regulating the acquisition of these nutrients from soil and translocation to grains in cereal/legume intercropping systems. While cereals facilitate Fe/Zn uptake by legumes, there is no direct mechanistic evidence to support interspecific P facilitation. The concentrations of P, Fe and Zn in grains are not only determined by interspecific mobilization and uptake facilitation of these nutrients from soil but also influenced by grain yield and translocation of the nutrients from roots to shoots.
Yanfang Xue, Haiyong Xia, Peter Christie, Zheng Zhang, Long Li, Caixian Tang, 2016, 'Crop acquisition of phosphorus, iron and zinc from soil in cereal/legume intercropping systems: a critical review', Annals of Botany, vol. 117, no. 3, pp. 363-377 http://dx.doi.org/10.1093/aob/mcv182