Critical Levels of Boron in Soils for Cauliflower (Brassica oleracea Var. Botrytis)

Abstract

Influence of boron (B) application to cauliflower (Brassica oleracea var. botrytis) was investigated in a pot experiment taking 15 Inceptisols with four levels of B. The critical levels of B for deficiency, adequacy and toxicity in soil and in cauliflower plant were also determined. Hot-calcium chloride (CaCl₂) extractable B in these soils varied from 0.33 to 0.78 mg kg^-1 and its content for deficiency to cauliflower was 0.48 mg kg^-1. Boron application significantly increased cauliflower yield, plant B concentration and uptake of B. The critical plant B concentrations for deficiency, sufficiency and toxicity varied with the growth stages and the values being 26, 31 and 48 mg kg^-1 at 50 days of growth and 17, 24 and 35.5 mg kg^-1 at harvest, respectively. The study also recommends application of fertilizer B at the rate 0.9–4.5 kg ha^-1 for optimum B nutrition to cauliflower in Inceptisols of the Gangetic plains of India.

Keywords:

• critical B concentration
• hot-CaCl₂
• cauliflower
• Inceptisols