Registration of three cotton germplasm lines with extremely high fiber strength derived from crosses between Upland cotton and diploid Gossypium species

Abstract

USDA-ARS-GMD 2427 (Reg. no. GP-1158, PI 706599), USDA-ARS-GMD 2442 (Reg. no. GP-1159, PI 706600), and USDA-ARS-GMD 24141 (Reg. no. GP-1157, PI 706598) are noncommercial breeding lines of cotton (Gossypium hirsutum L.) released by the USDA-ARS at Stoneville, MS, in 2024. Tetraploid hybrids of tri-species, G. arboreum L/G. hirsutum/G. aridum Skovst (AADD) was derived from crosses between G. arboreum (AA) and a hexaploid bridge line, G. hirsutum/G. aridum (AADDDD) followed by three backcrosses to Upland cotton. Lines were selected in F₅ progenies and were evaluated at Stoneville in 2017, 2018, and 2019 and at seven locations across the US Cotton Belt in 2020 in the Regional High Quality test. In all tests, the three lines had significantly higher fiber strength than checks, 5% to 25% higher than the high fiber quality check, MD 15, and 10% to 18% higher than commercial checks. Other fiber properties including fiber length, uniformity, elongation, and micronaire were in acceptable ranges. Yield of the three lines was low to moderate compared with the high-yielding checks. The three lines had significantly different fiber strength and lint yield among themselves. USDA-ARS-GMD 24141 had high fiber strength with yield equivalent to SureGrow 747 and higher than MD 15. This line had intermediate resistance to Fusarium wilt race 4 compared to the susceptible checks and resistant checks. USDA-ARS-GMD 24141 is registered with another two sister lines, USDA-ARS-GMD 2427 and USDA-ARS-GMD 2442. The released germplasm lines can be used by breeders for genetic improvement of fiber strength and by molecular scientists for identification of high fiber strength genes and their genomic locations.