Magnesium Absorption by Plants

Magnesium (Mg), a part of the group of essential plant nutrients, is the main constituent of the chlorophyll molecule, which is essential for photosynthesis. Important in the filling of grains and fruits, magnesium enhances the absorption of phosphorus and is closely associated with calcium and potassium. It participates as enzyme activator.

 

By nature, magnesium is ore and its main sources in soil are minerals such as biotite, hornblende, dolomite and (ferro-magnesian) chlorite. Other sources of secondary minerals are chlorite, illite, montmorillonite and vermiculite. It is adsorbed on the surfaces of clays and organic matter, so magnesium is in the soil solution and, through the exchangeable cation Mg2+, to a lesser extent than calcium.

 

Its cycle is similar to potassium, but it is not fixed by clays. Therefore, it can leach easily, especially in medium and coarse textures.

Magnesium is very mobile in soil, and reaches the root mainly not only by diffusion but also by mass flow. Plants absorb as magnesium as Mg2+. The amount of magnesium that moves by diffusion is related to the intensity of the element in the soil solution, with the physical properties (e.g., texture, porosity), temperature, soil moisture, pH and cation exchange capacity.

 

The uptake of magnesium by plants is also influenced by the concentration of other nutrients such as calcium and potassium cations. It is essential in a fertilization program to encourage and maintain appropriate ratios of calcium/magnesium, magnesium/potassium and calcium+magnesium/potassium. These relationships contribute to an adequate balance in the soil to provide optimum nutritional balance of plants and therefore excellent yields and crop quality.

 

Magnesium deficiency symptoms appear first on lower (i.e., older) leaves due to the high mobility of the element within the plant. Initially there is a slight yellowing, but the veins remain green. In crops such as corn, yellow or light green stripes appear on the leaves, while the veins remain green. In some crops, as the deficiency progresses, a reddish-purple color develops, but the veins remain green. In oil palms, a slight discoloration from the tip of the leaflets to the center of the leaf leaves the veins green. In citrus, an inter-vein yellowing on the leaves is found with a portion of green tissue in the form of an inverted V at the base of the leaf. Mg2 deficiencies may occur in acidic soils, sandy soils or where high levels of ammonium (NH4) or potassium (K) are present.

 

The sources of magnesium commonly used, depending on the type of soils, include magnesium carbonate (i.e., dolomite), and magnesium oxides and sulfates. As well as being a supply of nutrients, magnesium helps reduce the acidity caused mainly by exchangeable Al3+ and H+ ions (i.e., acidic soils). There are other sources, such as NPK-Complex fertilizers or from chemical reactions that, in addition to containing nitrogen, phosphorus and potassium, include magnesium, calcium, sulfur and trace elements, all in a single grain. These fertilizers are ideal balanced formulas for every stage of different crops such as planting, growth, development and production.

Abonos Colombianos (ABOCOL) is a company serving the agricultural sector and industrial markets in Central America, the Caribbean and the Andean region with raw materials of the highest quality.

 

Its leading products include fertilizers, industrial products (phosphoric acid, nitric acid, magnesium oxide ash, granulated urea, magnesium, etc.) and the Comprehensive Plans of Nutrition.

 

Learn more about the Profile, Products, Address and Phone Number for Abonos Colombianos.

 

Or, contact Abonos Colombianos directly for further information on its industrial grade magnesium.