Steven Dale Tanksley (born April 7, 1954) is the Chief Technology Officer of Nature Source Improved Plants.

[2] In 1993, Tanksley was the head of a Cornell research group that isolated and subsequently cloned a disease-resistance gene in tomato plants.

[3] Much of Tanksley's work focused on identifying alleles from wild relatives of crops that could be useful in improving cultivated varieties, for example fruit size and shape in tomato,[4] using the technology Marker-assisted selection (MAS).

He led work developing the advanced backcross Quantitative Trait Loci (QTL) method, facilitating the introgression of new alleles into cultivated breeding lines.

[11] He has received the Alexander von Humboldt Foundation Award,[12] the Martin Gibbs Medal of the American Society of Plant Biologists,[13] and the Wolf Prize in Agriculture.