1. Federal Univ. of Santa Maria Agricultural Engineering Dep. Santa Maria Brazil
2. Kansas State Univ. Dep. of Agronomy Manhattan KS USA
3. Federal Univ. of Santa Maria Soil Science Dep. Santa Maria Brazil
4. Monsanto Argentina Dep. of Technology and Development of Corn and Sorghum Buenos Aires Argentina
5. Potsdam Institute for Climate Impact Research (PIK) Member of the Leibniz Association P.O. Box 60 12 03 14412 Potsdam Germany