Genetic improvement for phosphorus efficiency in soybean: a radical approach.

BACKGROUND Low phosphorus (P) availability is a major constraint to soybean growth and production. Developing P-efficient soybean varieties that can efficiently utilize native P and added P in the soils would be a sustainable and economical approach to soybean production. SCOPE This review summarizes the possible mechanisms for P efficiency and genetic strategies to improve P efficiency in soybean with examples from several case studies. It also highlights potential obstacles and depicts future perspectives in 'root breeding'. CONCLUSIONS This review provides new insights into the mechanisms of P efficiency and breeding strategies for this trait in soybean. Root biology is a new frontier of plant biology. Substantial efforts are now focusing on increasing soybean P efficiency through 'root breeding'. To advance this area, additional collaborations between plant breeders and physiologists, as well as applied and theoretical research are needed to develop more soybean varieties with enhanced P efficiency through root modification, which might contribute to reduced use of P fertilizers, expanding agriculture on low-P soils, and achieving more sustainable agriculture.