Narrative
A set of five upland (Gossypillm hirsllfllm) cotton germplasm lines which includes three semiglanded lines (GVSI, GVS2, GVS3) with varying gland densities and seed gossypol content, a totally glanded line (GVS4) and a totally glandless line (GVS5) all in the same genetic background, Stoneville 7 A. GVS4 and GVS5 are near isogenic lines (NILs); GVS4 has normal glanding and gossypol in the seed, while GVS5 has no glands or gossypol in the seed. In the Fl1? the seed gossypol content of GVSI, GVS2 and GVS3 was 0.90, 0.49, and 0.51% of the total seed weight, respectively. The parental line Stoneville 7 A glanded had 1.54% and the Stoneville 7 A glandless had 0.00% seed gossypol. The NILs GVS4 and GVS5 had 1.49% and 0.00% seed gossypol. GVS I, GVS2 and GVS3 have normal stem glanding similar to the glanded parent. Calyx glanding is normal in GVS 1 while GVS2 and GVS3 have a 17% reduction. Boll glanding scores were 100% (GVSI), 66% (GVS2) and 50% (GVS3) of the glanded parent. In the semi-glanded lines, leaf glanding was reduced at the end of the growing season, but the leaves were always glanded on veins and margins. GVS4 plants have normal glanding throughout and GVS5 plants are completely devoid of glands. Lint yields averaged 1,584 kg/ha for GVSI, 1,302 kg/ha for GVS2, 1,363 kg/ha for GVS3 and 1,632 kg/ha for the yield check SG 747. Lint yields for GVS4 and GVS5 were 1,535 and 1,347 kg/ha, respectively. Fiber length (HVI-UHM) was 30.48 mm for GVSI, 29.08 mm for GVS2, 28.83 mm for GVS3, 30.16 mm for GVS4 and 29.21 mm for GVS5 compared to the quality check FM 832 (32.13 mm) and yield check SG 747 (30.48 mm). Fiber strength was 298 kN m/kg for GVS I, 326 kN m/kg for GVS2, 278 kN m/kg for GVS3, GVS4 285 kN m/kg and 278 kN m/kg for GVS5, while FM 832 had 330 kN m/kg. Micronaire for FM 832, was 4.8 and 5.5 (GVSI), 5.3 (GVS2), 5.8 (GVS3), and 4.2 (GVS4, GVS5). These lines will be valuable tools for mapping projects, host plant resistance studies and a genetic resource to develop low seed gossypol lines.