ARS | Publication request: PLANT NUTRITION AND ROOT GROWTH RELATED TO CA AND MG SATURATION IN SOIL

Submitted to: Soil Science Society of America Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: November 5, 2000
Publication Date: N/A

Technical Abstract: Soil erosion process affects not only soil but also water quality. The type of cations on the exchange complex is an important factor in the dispersion/flocculation process, and consequently on soil erosion. Studies have shown that Ca over Mg can decrease erosion, however, more needs to be done in order to understand the relation between Ca and Mg on the exchange complex with soil structure, erosion, water quality and plant nutrition. The specific objectives of this study was to analyze the effect of Ca and Mg ratio on the concentration of macronutrients in plant tissue and in soil as well as root growth in corn. In order to reach this objective, we carried out a greenhouse experiment involving treatments with different Ca/Mg ratios (90:10; 80:20; 50:50; 20:80 and 10:90), gypsum (5000 kg/ha) and control. For obtaining the different Ca/Mg ratios the Miami soil was saturated with Ca/MgC12 and leached with Ca/MgSO4 solutions. Before seeding corn, all pots (1 kg) received N fertilizer at rate of 176 kg/ha according to the recommendation for the Corn Belt Region. P and K were not applied based on the soil analysis. Plants were harvested 20 days after germination and shoots, roots and soil samples were collected for analysis. Biomass and concentration of nutrients, especially Ca, Mg and K, in plant and soil were different among treatments.