Professor Benham E. L. Lockhart was born in Kingstown, St. Vincent, the West Indies, in 1945. He earned his B.Sc. degree in tropical agriculture at the University of the West Indies in Trinidad in 1965 and his Ph.D. degree in plant pathology from the University of California at Riverside in 1969. Between 1969 and 1971, he was a postdoctoral fellow with M. K. Brakke at the University of Nebraska and with D. E. Schlegel at the University of California, Berkeley. He has been a faculty member of the Department of Plant Pathology at the University of Minnesota since 1971, becoming professor in 1986.
In 1971, Lockhart accepted an assignment to the fledging Institut Agronomique et Veterinaire at Hassan II University in Rabat, Morocco. Lockhart served in Morocco for a total of 12 years, from 1971 through 1976 and from 1981 through 1986. During his 12 years, he developed two modern laboratories for plant virus research. One was at the main campus in Rabat and one in Agadir at the center of the vegetable growing area in southern Morocco. From these laboratories, Lockhart and his students and collaborators identified and characterized many of the most serious plant viruses affecting Moroccan agriculture. He designed his teaching and research in an integrated fashion to meet the demands of education in a developing nation. He adapted his life style to be compatible with the customs of Morocco. A native English speaker, he became proficient in several languages. He taught his students in French and increased his effectiveness by becoming proficient in written and classical Arabic and Spanish.
In Morocco, Professor Lockhart designed research and teaching efforts for maximum effectiveness in a developing nation. To enhance hands on, practical and scientific education for Moroccan students, he initiated a cooperative effort with H. U. Fisher of Germany designed to identify the most serious virus diseases of Moroccan vegetable crops. Each undergraduate student who studied with Professor Lockhart researched a virus disease of an important Moroccan vegetable or fruit crop. Professor Lockhart became these students’ advisor and mentor. He arranged for many of them to attend universities in Europe and the United States for advanced graduate education. Advanced students returned to Morocco, did more detailed research on local virus problems, and received their Ph.D. degree under Lockhart’s supervision. In 1975, King Hassan II visited Professor Lockhart and his students at his plant virology laboratory at Hassan II University. Today, plant virology research and teaching at Hassan II University is conducted by Moroccan nationals who obtained their Ph.D. degrees under Professor Lockhart’s direction. In 1993, the Moroccan ambassador to the United States traveled to Minnesota to present Professor Lockhart with a gold medallion to honor his dedicated service to Moroccan science and agriculture. In 1996, Lockhart was given the APS Professional Service Award for his international work.
At Minnesota, Lockhart began an extensive research program into a little known group of nonenveloped bacilliform plant viruses transmitted by mealybugs and through seed. He and his students were the first to determine that the genomes of these viruses consisted of circular, double-stranded (ds) DNA. He, along with his Minnesota collaborator Dr. Olszewski and their students, was the first to obtain full-length genomic sequences of several of these viruses, including Commelina yellow mottle virus (CoYMV). Professor Lockhart named his new group the “Badnavirus” group and proposed CoYMV as its type member. The genus Badnavirus is now accepted by the International Committee for Taxonomy of Viruses.
Intensive research by Lockhart and his collaborators and other laboratories into the molecular genetics of the badnaviruses demonstrated their plant pararetrovirus nature. They showed that CoYMV replicated its genome in a manner similar to the caulimoviruses. Their research revealed a viral-encoded reverse transcriptase was responsible for replication of the dsDNA viral genome via an RNA intermediary. Most recently, he and colleagues discovered that badnavirus sequences that are integrated into the plant chromosomal DNA can cause whole plant infections. This was a very important discovery from both the basic science and the plant pathology perspective. Infections that are caused by the integrated Banana streak virus (BSV) genome are problematic for several different banana breeding programs. Following the BSV work, he discovered that integrated Tobacco vein clearing virus sequences can also cause infection. This work has also led to the hypothesis that genetic, physiological, and environmental factors must be involved in the activation of integrated sequences. This hypothesis stems in part from epidemiological studies performed by Lockhart. Lockhart’s discovery of the badnaviruses and the de novo disease expression resulting from recombination of the pararetroviral sequences that were integrated into the host genome to form an episomal virus are original research discoveries of great significance to virology and to plant pathology.
Because of his expertise in plant virology and international education and agriculture, Professor Lockhart has been in great demand for international consulting and advising. In 1977, he was a member of the ICPP team for planning integrated pest management training in Tunisia. In 1978, he served as a consultant to the U.S. National Academy of Science’s Board for Science and Technology for International Development in Cameroon, and returned to that area of Africa as an AID consultant in 1979. Between 1979 and 1990, he served as a consultant or advisor to USAID, the United Nations, and various other organizations on international development programs in Bolivia (1979 and 1986), Cuba (1979), Zaire (1980 and 1989), Tunisia (1982), St. Vincent (1986), Rwanda, Kenya, Nigeria, Togo, Cote d’Ivoire, Thailand, and Mauritius (1990). In recent years, his finding that commercial sugarcane and banana are almost uniformly infected with badnaviruses has led his active advising and consulting in Barbados (1992), Cuba (1992), Brazil and Ghana (1993), Australia (1994), and Nigeria (1995). In 1997, he attended the World Bank Planning Conference in Guadeloupe to coordinate the research activities related to the control of diseases and pests of banana and plantain.
