Registration of MD25‐26ne, MD25‐27, and MD25‐87 Germplasm Lines of Cotton with Superior Yield, Fiber Quality, and Pest Resistance

Abstract

Three noncommercial cotton (Gossypium hirsutum L.) lines were released by the USDA‐ARS: MD25‐26ne (Reg. No. GP‐962, PI 666042), MD25‐27 (Reg. No. GP‐963, PI 666043), and MD25‐87 (Reg. No. GP‐964, PI 666044). These three lines are reselections out of MD 25. The objective of this research was to select lines with combinations of yield and fiber quality that were superior to those of MD 25. Starting with 153 F3 random MD 25 selections, reselections were made in 2009, 2010, and 2011 that resulted in three MD lines being retained. The 2010 and 2011 strains tests from multiple Stoneville environments showed that the three selected MD 25 lines had an average yield of 1517 kg ha−1, whereas the average yield of MD 25 itself was 1363 kg ha−1. In 2011, across the eight Regional High Quality (RHQ) Tests, the average yields of the three MD 25 selections and of the 12 transgenic cultivars were 1276 and 1295 kg ha−1, respectively, and their average yarn tenacities were 135 and 117 mN tex−1, respectively. In 2011, average yields across 13 locations in the Regional Breeders Testing Network (RBTN) for the three MD25 lines and for the three test checks were 1487 and 1413 kg ha−1. The average RBTN fiber‐quality scores for the three selections and the three RBTN check cultivars were 78.7 and 52.2. None of the other 24 test entries exceeded the average of the three MD 25 lines. For the second fiber‐quality score (QS2), the ranks of the three entries were 1, 2, and 4. The average QS2s for the three MD 25 lines and three check cultivars were 81.2 and 67.5. In other RBTN and RHQ tests, the three selected MD 25 lines showed resistance to tarnished plant bugs (Lygus spp.) and good resistance to the root‐knot nematode [Meloidogyne incognita (Kofoid and White) Chitwood]. The combination of high yield, good fiber quality, and pest resistance make these three lines useful for further cotton improvement.