Działanie nawożenia magnezem na rośliny i gleby. Część I. Plonowanie roślin w zależnośći od zasobności gleb w różne formy magnezu

During 3 years (1990-1992) the pot experiment on 15 soils with the red clover and Italian ryegrass were conducted. Each of soil was without Mg treatment or with treatment of 0.04 g Mg/1 kg of the soil. The soils were very differentiated in the content of various forms of magnesium (2.9-22.7 mg Mg/100 g of the soil), humus (0.9-2.7%) and soil particles <0.02 mm (6-25%). The content of different form of Mg in the soil (active, exchangeable, available after Schachtschabel and EUF and nonexchangeable) depended first of all upon thDuring 3 years (1990-1992) the pot experiment on 15 soils with the red clover and Italian ryegrass were conducted. Each of soil was without Mg treatment or with treatment of 0.04 g Mg/1 kg of the soil. The soils were very differentiated in the content of various forms of magnesium (2.9-22.7 mg Mg/100 g of the soil), humus (0.9-2.7%) and soil particles <0.02 mm (6-25%). The content of different form of Mg in the soil (active, exchangeable, available after Schachtschabel and EUF and nonexchangeable) depended first of all upon the sorption capacity, the content, later on the humus and at least on the content of soil particles <0.02 mm. Application of magnesium increased the yields of red clover and Italian ryegrass when soil contained 1 3.5-4.5 mg of exchangeable magnesium per 100 g of the soil. The increase of yield of plants after Mg application could be predicted most accurately on the basis of the content of Mg (extractable in 0.01 M CaCl₂) and in smaller degree on the basis of the content of available detected by EUF, and Schachtschabel methods.e sorption capacity, the content, later on the humus and at least on the content of soil particles <0.02 mm. Application of magnesium increased the yields of red clover and Italian ryegrass when soil contained 1 3.5-4.5 mg of exchangeable magnesium per 100 g of the soil. The increase of yield of plants after Mg application could be predicted most accurately on the basis of the content of Mg (extractable in 0.01 M CaCl₂) and in smaller degree on the basis of the content of available detected by EUF, and Schachtschabel methods.