Lint development and properties of fifteen fuzzless seed lines of Upland cotton (Gossypium hirsutum L.)

Fifteen fuzzless seed lines in “obsolete” backgrounds of Upland cotton (Gossypium hirsutum L.) were obtained from the National Cotton Germplasm Collection and evaluated for fuzzless seed genotype, lint percent, and lint quality. Fourteen of these fifteen lines were found to be homozygous for the dominant fuzzless seed allele N1. Only one line was homozygous for the recessive fuzzless seed allele n2. The measured lint percent of each line was very stable through time, however, large variability existed between many of the N1 lines ranging from 0.7 to 23.6% lint. The lint percent for the n2 line was 24.4%. Scanning electron microscopy was used to differentiate patterns of lint initiation on 1 day post anthesis ovules. General patterns included: first, lint initiation restricted to the chalazal end of the seed crest; second, lint initiation along the seed crest and laterally around the chalazal end of the ovule; and third, lint initiation covered all but the micropylar end of the ovule. Lint quality was evaluated for each line using the Advanced Fiber Information System (AFIS) which included measurements of length, maturity, and fineness. The means of each measurement varied among the fuzzless seed lines with significant differences between fiber length, short fiber content, immature fiber content, fineness, and maturity ratio. No correlation was found between lint percent and any of the lint quality measurements. These lines will provide a valuable resource for the study of fiber initiation and lint quality.