VARIATION IN MINERAL CONTENT OF SASKATCHEWAN FEED GRAINS

Abstract

The concentration of Ca, P, Mg, K, Zn, Cu, Mn, Fe and Se were determined in wheat, barley and oat cultivars grown in four soil zones incorporating two soil types during a 5-yr period. Ca and K in Saskatchewan grains were much lower than published values, while Zn and Fe values were much higher. Se contents in each grain averaged 0.25 ppm and were substantially below values reported in the literature. Se and Cu levels were extremely variable (CV = 31–81%), but coefficients of variation (CV) for other minerals ranged from 9 to 35%. The effects of season, soil zone, soil type and cultivar on composition of Ca, P, Mg and K were significant in most grains. Seasonal effects on Zn, Cu, Mn and Fe were quite marked, but soil type had little effect and there were few significant differences between cultivars. Grain samples from Gray soil locations were characteristically high in Zn and low in Mn. Average Se content in grain from the Brown soil zone (0.39–0.55 ppm) was highest. There was a progressive decrease through the Dark Brown and Black soils to very low levels in samples from the Gray soil zone (0.06–0.07 ppm). In each type of grain, clay soils were associated with higher Se levels than loam soils.