Thomas Wallace Whitaker (August 13, 1904 – November 29, 1993) was an American botanist and horticulturist who spent most of his career working as a geneticist for the United States Department of Agriculture (USDA).

[1] He grew up on a farm and worked his way through college, graduating from University of California, Davis in 1927 with a bachelor of science degree.

[1][4] Whitaker specialized in amaryllis, cantaloupes and other Cucurbita, and lettuce in the search for disease resistance and better taste, and he investigated plant systematics.

Robinson, both academics in biological sciences, stated that Whitaker did more to advance knowledge of cucurbits than any other single person, and dedicated the germplasm section of the conference "Cucurbitaceae '98" to him.

He was also the recipient in 1976 of that society's highest award, making him a "Distinguished Fellow of the Botanical Society of America": "For distinguished contributions to the understanding of economic plants, notably their improvement, and for a unique contribution in interpreting this understanding in terms of their domestication and their influence on the development of civilizations.