Mineral element concentrations in acid soil tolerant and susceptible sorghum genotypes

Abstract

Studies were conducted to determine mineral element concentrations in leaves of sorghum [Sorghum bicolor (L.) Moench] genotypes that were tolerant and susceptible to acid soil conditions, and to assess imbalances and changes in mineral elements in these genotypes grown at 60 (relatively severe Al stress, pH 4.1) and 40% (less severe Al stress, pH 4.6) Al saturation on an acid ultisol in Colombia, South America. Leaf concentrations of S, K, Al, Mn, and Fe were lower and concentrations of Ca and Si were higher in tolerant genotypes when plants were grown at 40 compared to 60% Al saturation. Susceptible genotypes had higher dry matter yield and leaf concentrations of Ca and Si, and lower concentrations of Mg, Al, Mn, Fe, and Zn when plants were grown at 40 compared to 60% Al saturation. At 60% Al saturation tolerant genotypes had higher dry matter yields and concentrations of Ca and Si and lower concentrations of P, S, Al, and Fe than susceptible genotypes. At 40% Al saturation, tolerant genotypes had higher dry matter yield and lower concentration of N, P, and S than susceptible genotypes. The largest changes in growth and mineral element concentrations were for susceptible genotypes grown at 60 compared to 40% Al saturation. The elements to show the greatest amount of change were increases in Ca and Si and decreases in Al, Mn, and Fe when plants were grown at 40 compared to 60% Al saturation.

Key words:

• Al and Mn toxicity
• Dry matter yield
• Mineral deficiencies
• Mineral imbalances
• Plant adaptation
• Si interactions
• Sorghum bicolor

Notes

Published as Paper No. 8375, Journal Series, Nebraska Agricultural Research Division, from Projects UN‐114 (Nebraska) and MS‐111 (Mississippi). Supported in part by the International Sorghum/ Millet Collaborative Research Support Program (INTSORMIL CRSP) on U.S. Aid for International Development Grant No. AID/DAN‐1254‐G‐SS‐5065–00.