Morris Lieberman, 62, a plant physiologist at the Beltsville Agricultural Research Station who specialized in methods of preserving perishable foods, died of leukemia Monday at George Washington University Hospital.

Dr. Lieberman joined the Agricultural Research Service at Beltsville in 1948. He was known for his work on the role of plant hormones and plant growth regulators in the aging process of flowers, fruits, vegetables and seeds and the relationship these have to preserving food.

Last year, he directed a NATO-sponsored lecture series in Greece on post-harvest physiology and crop preservation.

Dr. Lieberman, who lived in Silver Spring, was the author of more than 100 articles in professional publications. He was a fellow of the American Association for the Advancement of Science and a member of the American and Japanese societies of plant physiologists, the American Society of Biological Chemists, the American Chemical Society, the Federation of American Societies for Experimental Biology and the International Plant Growth Hormone Association.

A native of Brooklyn, Dr. Lieberman graduated from the City College of New York. After World War II service in the Army Air Forces, he earned a master's degree at Rutgers University. He moved to this area when he joined Agriculture and later earned a doctorate at the University of Maryland.

Survivors include his wife, the former Ferol Slate, of Silver Spring; a son, Benjamin, of Gaithersburg, and two sisters, Alice Schnell and Esther Ganeles, both of Queens, N.Y.