1. Department of Soils and Natural Resources, Faculty of Agronomy, University of Concepcion, Chillán, Chile
2. Faculty of Agronomy, University of Concepcion, Chillán, Chile
3. Department of Silviculture, Faculty of Forest Sciences, University of Concepcion, Concepción, Chile
4. IR3 initiative, Food and Agriculture Organization (FAO) of the United Nations, Tegucigalpa, Honduras
5. United States Department of Agriculture, Agricultural Research Service., Utah State University, Logan, Utah, USA