1. Dep. of Crop and Soil Sciences Univ. of Georgia 2329 Rainwater Road Tifton GA 31793 USA
2. Dep. of Plant Sciences Univ. of Idaho Aberdeen Research and Extension Center Aberdeen ID 83210 USA
3. Dep. of Agricultural and Biological Engineering Univ. of Florida Frazier Rogers Hall Gainesville FL 32611 USA
4. Institute for Sustainable Food Systems Univ. of Florida Frazier Rogers Hall Gainesville FL 32611 USA
5. Natural Resources Management and Agricultural Engineering Dep. Agricultural Univ. of Athens 75 Iera Odos Str. Greece 11853