Role of magnesium in combination with liming in alleviating acid-soil stress with the aluminium-sensitive sorghum genotype CV323

• Published in: Plant and soil 1991-09, Vol.136 (1), p.65-71
• Main Authors: Tan, K. (Landbouwuniversiteit Wageningen (Netherlands). Vakgroep Bodemkunde en Plantevoeding), Keltjens, W.G, Findenegg, G.R
• Format: Article
• Language: English
• Subjects: ABSORCION DE SUBSTANCIAS NUTRITIVAS; ABSORPTION DE SUBSTANCES NUTRITIVES; ACID SOILS; Agronomy. Soil science and plant productions; ALUMINIO; ALUMINIUM; Biological and medical sciences; Fertilization; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Genotypes; Liming; MAGNESIO; MAGNESIUM; NUTRIENT UPTAKE; Orchard soils; Other nutrients. Amendments. Solid and liquid wastes. Sludges and slurries; Plant roots; Plants; RACINE; RAICES; ROOTS; Sandy loam soils; Sectie Bodemkwaliteit; Soil solution; SOIL TOXICITY; Soil-plant relationships. Soil fertility. Fertilization. Amendments; SOL ACIDE; Sorghum; SORGHUM BICOLOR; Sub-department of Soil Quality; SUELO ACIDO; TOXICIDAD DEL SUELO; TOXICITE DU SOL
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/BF02465221

An experiment to study the effects of Mg nutrition on root and shoot development of the Al-sensitive sorghum (Sorghum bicolor (L.) Moench) genotype CV323 grown in pots of sandy loam under different acid soil stress is reported. This experiment had a factorial design: four rates of liming were combined with four rates of Mg fertilization. When no Mg was added, the pH of the soil solutions (collected in ceramic cups) increased from 4.0 (unlimed) to 4.2, 4.7 and 5.9 at the increasing rates of liming. After 30 days of growth dry matter yields of the limed treatments were 40%, 115% and 199% higher than that of the unlimed treatment. Without liming and at the highest liming rate, adding Mg did not affect plant biomass significantly. At the two intermediate levels of liming, however, 11.3 mg extra Mg per kg soil increased dry matter yield to the same level as found at the highest liming rate. Concentrations of Mg in the soil solutions rose after Mg was added and fell when lime was added, but adding both Mg and lime increased Mg concentrations in the plant shoots. In plants of the limed treatments, dry matter yield was correlated closely with the Mg concentration in the shoot. This was not so in the unlimed treatments. Furthermore, in the unlimed treatments root development was inhibited, but reduced Mg uptake by the plants resulted mainly from the direct effect of Al- (or H-) ions in the soil solution rather than from impaired root development. It is concluded that Mg fertilization counteracted the interfering effects of Al-and H ions on Mg uptake.