Vol. 12, Special Issue 7 (2023)

Author(s):
Soniya VP and Bhindhu PS

Abstract:
An incubation study was conducted by supplying three levels of magnesium carbonate with and without the addition of recommended dose of calcium carbonate (250 kg ha^-1) and organic manure (20 t ha^-1) to one kilogram of soil to study the effect of magnesium carbonate as ameliorant. Soil pH, EC and available Magnesium were determined at weekly intervals for four months. The fractions of magnesium in soil were determined before and after the experiment. Higher soil pH and available magnesium were recorded in treatment supplied with the highest dose of magnesium carbonate with the addition of organic manure and calcium carbonate throughout the incubation period. Maximum release of magnesium from magnesium carbonate was in the eighth (133.89 mg kg^-1) week and was on par with seventh (129.55 mg kg^-1) and ninth (129.97 mg kg^-1) after incubation and decreased thereafter. Fractions of magnesium in the initial soil and after incubation were in the order mineral Mg> exchangeable Mg> acid soluble Mg> organic complexed Mg> water soluble Mg. The variations in acid soluble and mineral fraction between treatments substantiates the presence of magnesium carbonate as a solid phase throughout the incubation period, which could be a potential slow-release magnesium fertilizer to plants.