Botany Department, Lucknow University, Lucknow 226 007
Cauliflower (Brassica oleraeca L. var. botrytis) Maghi was grown in refined sand at 3 levels of K - low (0.05 meg l−1), adequate (4 meg l−1) and excess (16 meg 1−1), 2 levels of Mg - deficient (0.04 meg l−1) and normal (4 meg l−1). A synergism between K and Mg was obtained in cauliflower when Mg deficiency accentuated the effects of low K by further lowering the biomass, concentration of chlorophyll a and b, starch, inorganic P, protein and activities of ATPase and pyruvate kinase, and stimulating the activities of acid phosphatase, peroxidase concentration of proline and non-reducing sugars. In cauliflower, low Mg enhanced further the effects of excess K, viz. increase in the activity of peroxidase and concentration of proline, sugars and starch and reduction in pyruvate kinase and chlorophyll contents thus reflecting a synergistic role of K and Mg. Low Mg resulted in a rudimentary, immature and loosely arranged curd at excess K and almost no curd formation at combined deficiency of both nutrients in cauliflower.
