TAM BB-2139 ELSU extra long staple upland germplasm

The minimum or nondiscount upper half mean length (UHML) of upland cotton, Gossypium hirsutum L., for consumption in the United States is 27 mm, while the minimum for international markets is 28 mm. This discrepancy is based on the remaining US spinning mills predominately using rotor spinning technology, while ring spinning predominates internationally. Along with increased international base for staple length, processors desire greater fiber strength, decreased short fiber content, and more uniform fiber length distributions to withstand ever-increasing processing speeds and rigor and to produce premium yarns with improved end use quality. A narrower micronaire range (or finer yet mature fibers) or finer fibers is also desirable. With increasing export of US cotton and advances in spinning technology, improvements of fiber quality parameters are essential for the competitiveness of US upland cotton. Producers receive premiums for improved fiber quality, and their product is more competitive with manmade fibers in the textile market. TAM BB-2139 ELSU (extra long staple upland) (Reg. no. GP-1071, PI 691840) exhibited UHML exceeding the control cultivars and averaged 35.5 mm UHML across six locations in central and south Texas in 2016–2017. It also averaged 36.6 mm in the 2016 USDA Regional High Quality Test when grown across nine locations in eight states. The minimum UHML for G. barbadense L., pima cotton, is 34.9 mm. TAM BB-2139 ELSU will provide upland cotton breeders with a source for improving UHML.