1. Department of Agricultural Resource Management, School of Agriculture, University of Embu, Embu, Kenya
2. Department of Land and Water Management, School of Agriculture, University of Embu, Embu, Kenya
3. Department of Plant Sciences, School of Pure and Applied Sciences, Kenyatta University, Nairobi, Kenya
4. Department of Biochemistry, Microbiology and Biotechnology, School of Pure and Applied Sciences, Kenyatta University, Nairobi, Kenya