Effect of applied boron on the accumulation of cations and their ratios to boron in radish (Raphanus sativus L.)

The present study was based on the hypothesis that B has close relationships with cations in soil-plant systems. A study was carried out to assess the influence of B on the concentration of cations and their ratios to boron in radish (cv. French breakfast) crop, using sand culture technique, under green house conditions. The experiment was laid out in a randomized complete block design and replicated three times. Boron was applied at the rate of 0, 0.25, 0.50, 1.0, 2.0, 3.0 and 5.0 mg B L-1 as H3BO3 along with a basal dose of modified complete nutrient solution based on the Long Ashton Formula. Results revealed that the concentrations of B and K in plants were increased and Ca, Mg and Na were significantly decreased. Generally, low and high levels of added B had interactive effects on the concentration of cations in radish plants. The K/Ca, K/Na and K/Mg ratios were increased and Ca/Mg decreased in plants with increasing B levels in the nutrient solution. Moreover, the cation ratios to boron such as K/B, Ca/B, Mg/B and Na/B significantly decreased in both plant tops and roots with increasing B levels in the nutrient solution. These ratios provided some indication for the interrelationships of boron with cations in plants. The present study suggests that the deficiency or excess of B not only affects the relative values of individual element, but it also affects the balance among cations or cations ratio to boron in radish plants.