Robert E. Perdue Jr., 86, a retired botanist who helped conduct research into the use of plants in cancer-treating medicines, died July 20 at Suburban Hospital in Bethesda after a stroke.

Dr. Perdue moved to the Washington area in the early 1950s and worked for the U.S. Geological Survey, where he helped map vegetation in China, India and Thailand.

He joined the U.S. Department of Agriculture in 1957 and worked for the Agricultural Research Service in Beltsville. In 1960, Dr. Perdue worked in cooperation with the National Cancer Institute to help procure plant samples to be tested for use in anti-cancer drugs.

After Dr. Perdue retired from the Agriculture Department in 1989, he started his own company that helped develop plant crops in Latin America. Beginning in 2006, he served as a consultant to HeteroGeneity, a private firm that promotes the use of plants in foods and pharmaceuticals.

Robert Edward Perdue Jr. was a Norfolk native and a 1949 botany graduate of the University of Maryland. He received a master’s degree in 1951 and a doctorate in 1957, both in botany from Harvard University.

According to his family, Dr. Perdue served as an officer in the Army’s 101st airborne division during World War II. He was shot in the knee during combat and later suffered a shrapnel wound from a land mine in Germany. His military decorations included the Bronze Star Medal and two Purple Hearts.

In 2010, Dr. Perdue self-published a book on the Office of Strategic Services, the wartime forerunner of the CIA, and its World War II operations in Greece. He was a North Bethesda resident.

His first marriage, to Gloria Pugh, ended in divorce.

Survivors include his wife of 35 years, Georgia Persinos Bergstrom Perdue of North Bethesda; three children from his first marriage, Robert E. Perdue III of Falling Waters, W.Va., Susan Sherwin of Alpine, Utah, and Holly Boyle of Church Hill, Md.; 10 grandchildren; and nine great-grandchildren.