1. Department of Plant and Soil Science, Texas Tech University, Lubbock, TX, USA
2. Albrecht Daniel Thaer-Institut für Agrar- und Gartenbauwissenschaften, Humboldt-University to Berlin, Berlin, Germany
3. Department of Earth & Environmental Science, Botswana International University of Science & Technology, Palapye, Botswana
4. Department of Natural Resources and Environmental Sciences, Kisii University, Kisii, Kenya