1. Norwegian Univ. of Life Sciences; Dep. of Plant and Environmental Sciences; P.O. Box 5003 N-1432 Ås Norway
2. Mekelle Univ.; College of Dry land Agriculture and Natural Resources Dep. of Dry land Crop and Horticultural Sciences; P.O. Box 231 Mekelle Ethiopia
3. Nofima- The Norwegian Institute of Food, Fisheries and Aquaculture Research; Ås Norway