Effects of nitrogen fertilization on stored cabbage. III. Changes with time and distribution in outer-head leaves of the mineral contents

Abstract

The mineral content of N, P, K, Ca, Mg, S, Mn, Zn, Fe, Cu, Al, B and Mo in cabbage plants was measured on (1) leaf midribs at three sampling times from early heading in the field until the 126th day of storage at 1°C and 92% r.h., and (2) on the midrib, top and bottom parts of the outer-head leaves of cabbage cvs Safekeeper and Hidena after storage. Cabbages were from N treatments at 0, 90, 180 and 270 kg N ha-1 of calcium nitrate, ammonium nitrate and ammonium sulphate. Generally, the midrib mineral content decreased markedly from heading until the end of storage. The bottom leaf part of the tolerant cv. Hidena had a higher S, B, Mn and Mo contents while that of the disorder- susceptible cv. Safekeeper had a lower Mn/Zn ratio. The susceptibility of the basal leaf mesophyll to grey speck disease is tentatively explained by a Zn-induced Mn deficiency aggravated by nitrate treatments and lower S, B and Mo accumulation in tissues of the susceptible cultivar.