Registration of eight upland cotton (Gossypium hirsutum L.) germplasm lines with qFL-Chr.25, a fiber-length QTL introgressed from Gossypium barbadense

Eight upland cotton (Gossypium hirsutum L.) germplasm lines, GA qFL25-A1 (Reg. no. GP-1063, PI 690458), GA qFL25-A2 (Reg. no. GP-1064, PI 690459), GA qFL25-P1 (Reg. no. GP-1066, PI 690461), GA qFL25-P2 (Reg. no. GP-1065, PI 690460), GA 01,25-D1 (Reg. no. GP-1070, PI 690465), GA qFL25-D2 (Reg. no. GP-1069, PI 690464), GA qFL25-G1 (Reg. no. GP-1068, PI 690463), and GA qFL25-G2 (Reg. no. GP-1067, PI 690462), were developed by the Molecular Cotton Breeding Laboratory, Department of Crop and Soil Sciences, at the University of Georgia in Tifton, GA. These eight germplasm lines resulted from crossing 'Sealand 883' (SL883), a G. hirsutum line with significant introgression from G. barbadense L., with four diverse G. hirsutum parents, Acala SJ-4', 'Paymaster HS 26', 'Deltapine 50', and GA 2004089, an unreleased breeding line. Previous work identified qFL-Chr.25, a quantitative trait locus (QTL) inherited from G. barbadense with significant effect on fiber upper-half mean length (FL) carried by SL883. Bulked sister lines were selected with the aid of marker-assisted selection from several F3 . 5 segregating families from each of these four cross combinations to quantify the effect of the allele in sister lines with and without the QTL. The presence of the SL883 allele for qFL-Chr.25 resulted in FL increases of 0.6 mm (1.9%) to 3.5 mm (11.7%) compared with the corresponding sister lines without the QTL. These eight lines should be useful for marker-assisted improvement of fiber length.