1. Department of Plant Breeding and Seed Science, College of Agronomy, University of Agriculture, Makurdi, Nigeria
2. International Institute of Tropical Agriculture (IITA), Ibadan, Nigeria, c/o IITA LTD, Croydon, UK
3. Genetic Resource Program, International Maize and Wheat Improvement Center (CIMMYT), Texcoco, Mexico
4. Department of Crop Protection, Ahmadu Bello University, Zaria, Nigeria