– Assistant, Associate and Professor of Plant Pathology (Virology), Faculty of Agriculture, U. of k., 1976-1997 to date.
– Associate Professor of Plant Pathology (Virology), Faculty of Agric. Sc., U.A.E., 1992-96.
– Visiting Professor, Faculty of Science, University of Qatar, 1967.
– Professor of Plant Pathology (Virology), Faculty of Agric. University of Khartoum, Since 1999.