Cd content of durum wheat and canola as affected by nitrogen fertilization and tillage practises

Abstract

Cadmium is an element of concern as certain food crops can accumulate levels of Cd which are not toxic to the plant but maybe harmful to humans. Due to high concentrations of Cd currently found in some Canadian grains and oilseeds there is a need to determine the factors responsible for Cd uptake and accumulation in these crops. Two growth chamber studies were conducted to determine the effects of rates and placements of nitrogen fertilizers, including Ca(NO$\sb3)\sb2,$ urea, and (NH$\sb4)\sb2$SO$\sb4,$ on Cd concentration in durum wheat (Triticum turgidum cv. Medora). Fertilizer effects were examined on two soils, a Newdale clay loam (Orthic Black Chernozem) and a Cobfield fine loam (Gleyed Carbonated Rego Black Chernozem). A field study was conducted from 1992 to 1994 to determine the effects of fertilizer management and tillage practises on Cd concentration in crops. Durum wheat (Triticum turgidum cv. Sceptre) and canola (Brassica napus cv. Legend) were grown on two Orthic Black Chernozems, a Newdale clay loam and a Marringhurst fine sandy loam. Various commercial fertilizers were applied at 60 kg N ha$\sp{-1}$ to both crops either under conventional or zero tillage systems. (Abstract shortened by UMI.)