The mechanism of phloem mobility of boron

Recent evidence suggests that the production and translocation of polyols will influence the phloem mobility of B in higher plants. Here we have determined B transport in a number of plant species producing polyols, using B concentration gradient along a shoot and foliar 10B labelling techniques. Results demonstrate that B is phloem mobile in the species producing polyols. These results are discussed with reference to the formation and transport of B-polyol complexes in higher plants.