Abstract: | In pot trials using a range of soils from South-East Scotland, plant cobalt concentrations were significantly correlated with the amounts of cobalt extracted from soil with 0.05 M calcium chloride. Plant cobalt concentrations were also correlated with soil pH, showing a decrease with increasing soil pH. There were no significant correlations between plant cobalt concentrations and 0.5 M acetic acid-extractable cobalt, 0.04 M EDTA-exttactable cobalt, isotopically exchangeable cobalt or total soil cobalt. Uptake of cobalt by ryegrass from cobalt added to the soil was inversely related to both the ability of the soil to sorb cobalt and to soil pH. |