Uptake and Physiological Effects of Cadmium in Sugar Beet (Beta vulgaris) Related to Mineral Provision

Publisher Website
Google Scholar
Abstract
Sugar beet seedlings (Beta vulgaris L. cv. Monohill) were grown for 14 d on a nutrient solution based on the nutrient proportions in healthy plants. Nutrients were supplied either once at relatively high concentrations, or in small amounts with a daily incremental increase of 0·15 or 0·20 in accordance with an exponential growth rate. Cadmium (0, 0·6, 2·3, 50 or 20·0 μmol) was introduced either by a single addition or in daily increments of 0·15 or 0·20. Cadmium uptake, expressed as a percentage of total Cd2+ supplied, decreased with increasing total Cd2+ content and with decreasing availability of nutrients. With a daily supply of cadmium, net uptake, transport and content per unit of dry weight in roots and shoots were related to the total Cd2+ supplied. Cadmium caused growth retardation, increased root/whole-plant ratio, and decreased root-tip respiration and photosynthesis. At high initial nutrient concentrations, Cd2+ decreased the contents of sucrose, glucose, fructose, and starch per unit of dry weight. The opposite was found if nutrients were added daily. In the latter case, the dry weight/fresh weight ratio also increased. The effects of cadmium were related to [Cd2+] in proportion both to the root absorption area and to the nutrient concentration.

This publication has 0 references indexed in Scilit: