William E. Whitehouse, 89, a retired official of the Department of Agriculture who is considered by many to be the father of the American pistachio nut industry, died Oct. 17 in Leland Memorial Hospital in Riverdale after a heart attack. He had lived in College Park for the past 54 years.

Dr. Whitehouse joined the Agriculture Department's old plant exploration division in 1929. Later that year, he planned and conducted an exploratory mission in Turkestan and Iran to survey the pistachio industry there. He returned to this country after several months' travel, bringing with him samples of the best and healthiest pistachios he had found.

Further genetic refinement of these samples at Agriculture research facilities resulted in a plant, the Kerman, that could be grown in this country with great success.

Dr. Whitehouse received the Pistachio Association's first Annual Achievement to Industry Award in 1977. The award cited his pioneering work in developing the pistachio nut as a new crop in the United States and hailed him as "the father of the pistachio industry."

He was the 1968 recipient of the American Genetic Association's highest award, the Frank N. Meyer Memorial Medal, for his work in plant exploration. In 1978, the Agriculture Department introduced the "Whitehouse Pear," an ornamental pear tree named in his honor.

Dr. Whitehouse spent 34 years with Agriculture before retiring in 1963. During his last nine years he was head of the crop development investigations section in the crops research division of the Agricultural Research Service. During this time he helped formulate plans for the National Seed Storage Center in Fort Collins, Colo.

He was born in New Hampshire where he grew up on a farm. He was a pilot training instructor in the Army during World War I. After graduating from Oregon State University in 1915, he had worked for a time picking and packing fruit and working in orchards along the West Coast. He then went to Iowa State University where he earned a master's degree in horticulture, and taught and conducted research. He earned a doctorate in horticulture at the University of Maryland.

Dr. Whitehouse was a member of the American Society of Horticultural Science and the Cosmos Club. He was an honorary member of the Georgetown Club.

His wife, the former Helen Amelia Rosenbusch, died in 1948.

Survivors include two daughters, Donna Marie Whitehouse of Hyattsville, and Barbara W. Jones of Kailua, Hawaii, and one grandchild.