Stabilizing naked seed mutants in upland cotton (Gossypium hirsutum L.)

Two of the best described cotton fiber mutants are the naked seed loci N1N1 and n2n2. The objective of this research was to stabilize and evaluate fiber trait data of new naked seed mutants developed from the cultivars Atlas and SC 9023 using chemical mutagenesis. In 1997, Texas High Plains upland cotton (Gossypium hirsutum L.) cultivars were treated with 2.45% v/v ethyl methane sulfonate (EMS) and planted in the field. M3 seed from Atlas, Tejas, and SC 9023 mutant lines was identified with a partially fuzzless seed coat. The trait was stabilized between 2000 and 2003. Lines were evaluated for fiber quality, lint yield, and ginning efficiency in 2004, 2006, and 2007 at Lubbock, TX. In 2008, crosses were made between mutant lines and eight lines chosen for high fiber initiation, fiber quality, and lint yield. Selections in these segregating populations to stabilize the naked seed trait were made from 2010-2012. Lines exhibiting the uniform naked seed phenotype were evaluated for AFIS fiber quality, lint yield, percent lint, and fiber initiation. With continued improvement we hope to develop the elite lines necessary to commercialize this valuable trait.