1. a Ethiopian Institute of Agricultural Research, Forestry Research Center , P.O. Box 30708, Addis Ababa , Ethiopia
2. b Eco Mark Africa, African Eco-Labelling Mechanism Secretariat , 4th Floor, International House, P.O. Box 41607-00100, Nairobi , Kenya
3. c Wondo Genet College of Forestry and Natural Resources , P.O. Box 128, Shashemene , Ethiopia
4. d Addis Ababa University, Science Faculty, Biology Department , P.O. Box 31819, Addis Ababa , Ethiopia