Tuesday, November 14, 2006
162-6
Evaluation of Four Cotton Germplasm Pools for Fiber and Yield Characteristics.
Lori L. Hinze, USDA/ARS, 2881 F&B Road, College Station, TX 77845 and Arlene Tugel, 3JER NMSU, USDA-NRCS, NRCS Jornada Exp Range, Box 30003, Las Cruces, TX 88003-0003.
A diversity of cotton (Gossypium hirsutum L.) germplasm exists with characteristics useful for cotton improvement. This study was conducted to determine whether four germplasm pools could be developed to provide adapted germplasm resources for cotton breeders. The properties of dwarfing genes, race stocks, fiber quality, and glandless genes were evaluated by creating a germplasm pool for each characteristic. A narrow based (four parent) pool was assembled to study the dwarfing genes, and broad based (22 to 42 parent) pools were assembled for the remaining three groups under study. These four germplasm pools were evaluated on yield and fiber traits and compared to a cotton genetic standard, TM-1. The dwarf germplasm pool had an earlier maturity, and it was significantly lower yielding (1,396 g) when compared with an average of the three remaining germplasm pools (1,762 g) and with the TM-1 control (1,661 g). There were no significant differences in yield among the race, fiber, and glandless germplasm pools. Fiber properties were significantly lower in the dwarf pool (micronaire = 3.41; 50% fiber length = 0.536) than the averages for the race, fiber, and glandless pools (micronaire = 4.15; 50% fiber length = 0.563). Again, there were no significant differences in micronaire or 50% fiber length among the race, fiber, and glandless germplasm pools. The TM-1 control had an average micronaire value (3.90) and a significantly higher 50% fiber length (0.610) when compared to the germplasm pools. The race, fiber, and glandless germplasm pools show potential for improving cotton germplasm by increasing yield and/or improving fiber properties.