veryone knows that in addition to the three major elements of nitrogen, phosphorus and potassium, plant growth also depends on trace elements. Today, I will share with you the main functions of magnesium fertilizer and scientific application methods.

(1) The main functions of magnesium fertilizer

Magnesium is mainly present in chlorophyll, phytochrome and pectin, and plays an important role in photosynthesis. Magnesium ions are activators of many enzymes, promoting the conversion and metabolism of carbohydrates in the body, and promoting the synthesis of fats and proteins. Applying magnesium to oil crops can increase their oil content, and magnesium can also promote the absorption of silicon by crops. Applying magnesium fertilizer to magnesium-deficient soil can increase its oil content, and magnesium can also promote the absorption of silicon by crops. Applying magnesium fertilizer to magnesium-deficient soil can improve the effect of phosphorus fertilizer.

(2) Application technology of magnesium fertilizer

① Soil, crops and magnesium fertilizer application. The magnesium content in the soil is mainly affected by the parent material and weathering conditions. In rainy and high-temperature areas, the total magnesium content of the soil is low. When the exchangeable magnesium (Mg2+) content in the soil is lower than 50 mg/kg, the application of magnesium fertilizer has a significant yield-increasing effect. Potassium-rich soils, areas with long-term, high-volume potassium applications, and the application of lime to acidic soils are all prone to physiological magnesium deficiency. Cash crops like cotton and fruit trees are particularly sensitive to magnesium fertilizers and require higher amounts. Rice requires less magnesium than crops like sugarcane, potatoes, corn, and citrus. When the exchangeable magnesium content in paddy soil is 26-49 mg/kg, the yield increase from magnesium fertilizers is unstable.

② Magnesium fertilizer types and application. Common magnesium fertilizers contain 8%-20% magnesium in calcium magnesium phosphate fertilizers, approximately 10% magnesium sulfate, approximately 25% magnesium chloride, and 11%-13% dolomite powder. Calcium magnesium phosphate and dolomite powder are preferred for acidic soils, while magnesium chloride or magnesium sulfate is appropriate for alkaline soils. Magnesium fertilizer can be used as a base fertilizer or topdressing, applying 1-1.5 kg per mu (calculated as magnesium). For fruit trees like citrus, apply 0.5 kg of magnesium sulfate per plant. Magnesium sulfate is a water-soluble magnesium fertilizer that can be used as a foliar topdressing. Spray concentrations range from 1% to 2%, with approximately 50 kg of solution applied per mu.

This concludes my sharing of the main benefits of magnesium fertilizers and their scientific application methods. I hope you find this helpful.