DETERMINATION OF LOW BORON CONCENTRATIONS IN NUTRIENT SOLUTION

To study boron (B) deficiency and toxicity in plants in flowing soluti on culture, it is necessary to establish a wide range of solution B co ncentrations. The ability of inductively coupled plasma atomic emisson spectrophotometry (ICPAES) to determine solution B concentrations ran ging from 0.15 mu M to 925 mu M was investigated. The reliablity of B concentration determination in nutrient solutions containing <10 mu M B is poor. A technique, involving sorption by a B-specific resin (Ambe rlite-743), was established to concentrate the B present in low B nutr ient solutions and to enable reliable measurement using ICPAES followi ng elution from the resin. Acceptable, reproducible recoveries of B fr om low B solutions, containing known concentrations of B, were obtaine d using this technique. The technique enables the imposition, monitori ng and maintenance of solution B concentrations well below the direct detection limits of ICPAES and colorimetric procedures.