On the effect of ferrous sulphate on the available manganese in the soil and the uptake of manganese by the plant

Summary

Application of iron as ferrous sulphate or chloride to a loam not deficient in manganese had no effect on the yield but increased the uptake of manganese even in barley which grew vigorously.

In an experiment with sugar beet on two soils contrasted with regard to their available manganese supply, applications of manganese, iron and nitrogen were tested in all combinations. On the Købelev soil, not deficient in manganese, no increases in yields were obtained on addition of ferrous sulphate while increases in manganese uptake were found for all combinations of treatments except where iron was added in the presence of manganese.

On the manganese deficient Faarevejle soil, significantly higher increases in yields of roots were obtained from ferrous sulphate in the presence of nitrogen than in the presence of manganese. The effect of iron in the presence of nitrogen on the yield of tops was also significant. These treatments also gave the highest increases in manganese uptake.

The amounts of manganese extractable from the soils by magnesium nitrate over a range of pH 2–8 could be increased considerably by addition of ferrous sulphate.

The results support the suggestion that application of ferrous sulphate to some soils has the same effect as an addition of manganese.