The interactive effects of boron and macronutrients (P, K, Ca and Mg) on pod yield and chemical composition of pea (Pisum sativum)

Abstract

SummaryFour separate glasshouse experiments were conducted in solution culture using four levels of B (0, 0.5, 2 and 8 mg l−1) factorially combined with four levels of macronutrients (P, K, Ca and Mg). In all experiments B toxicity was the main factor responsible for pod yield reduction. This effect varied from 68% in the B+Ca combination to 40% for B + Mg and B + P. The effect of the macronutrient was B level-dependent. The highest yields, when B was a non-limiting factor, were related to the macronutrient level. Leaf B concentration was proportional to the B concentration in the substrate, and 350 mg kg−1, associated with 2 mg l−1 in the nutrient solution, was within the toxicity range. The effect on the other nutrients was primarily related to the associated macronutrient. The toxic effect of B on pod yield may be reduced by the addition of Mg at rates higher than those applied under normal conditions. Leaf concentration ranges of P, K, Ca, and Mg for normal pea growth were also established.