The U.S. National Cotton Germplasm Collection – Its Contents, Preservation, Characterization, and Evaluation

The early history of the cotton industry in the U.S. was, for the most part, a story of importation and adaptation of cottons from Mexico, Guatemala, and the tropics of the Western Hemi‐ sphere. By the 19th century there were two distinctive types of upland cotton, with distinctive origins, being grown in the U.S. One type, known as green-seeded cotton, was from southern Mexico. The other dominant type of upland, white-seeded cotton, had its origins in the central plateau of Mexico [1,2]. Although these cottons were grown extensively, no coordinated efforts were made to maintain the original stocks or their progeny. Modern, systematic collection and preservation of cotton in the U.S. only began in response to the outbreak of the boll weevil in the 1880’s [3]. Three collection trips between 1902 and 1906 were responsible for the introduc‐ tion of two cottons, Acala and Kekchi, which would contribute significantly to the develop‐ ment of modern U.S. cultivars [4]. From these initial collecting trips and ensuing trips, federal, university and state experiment stations began to assemble the germplasm collections. Also from these efforts there sprang collaborative efforts that were formalized into U.S. regional projects involving scientists and members from all aspects of the U.S. cotton industry. The first Regional Research Project was S-1 in 1950 (succeeded by many) and it established a priority of acquiring and studying diverse germplasm for cotton improvement [5-7]. Increased organization and centralization of germplasm activities was necessary to manage and increase