Comparing Manganese Sources for Spring Wheat Grown on Alkaline Soils

Abstract

The effectiveness of manganese (Mn) sulfate (28% Mn) and manganese oxide 77.5% Mn) as Mn fertilizers for spring wheat (Triticum aestivumL. cv. Brookton) was compared in a glasshouse experiment using two alkaline soils from south-western Australia. Yield of 56-day-old shoots and Mn content (Mn concentration multiplied by yield) of the shoots was used to compare effectiveness of the sources. Both sources were applied as fine powders at equivalent amounts of Mn and were mixed throughout both soils. For both soils, relative to the Mn sulfate (MnSO₄), the Mn oxide (MnO) was about 40% as effective for producing shoot dry matter and about half as effective at increasing the Mn content of shoot dry matter. Critical concentration (mg/kg) for producing 90% of maximum yield was about 11 for youngest emerged blades and 17 for whole shoots.

Keywords:

• Manganese sulfate
• Manganese oxide
• Wheat
• Effectiveness

Acknowledgments

The Chemistry Centre (WA) measured soil properties and manganese concentrations in tissue. Frank O’Donnell provided technical assistance. The Western Australian Department of Agriculture supplied finance and glasshouse facilities to do this study.