Submitted to: Euphytica
Publication Type: Peer reviewed journal
Publication Acceptance Date: 2/7/2001
Publication Date: 9/10/2001
Citation: KOHEL, R.J., YU, J., PARK, Y.H., LAZO, G.R. MOLECULAR MAPPING AND CHARACTERIZATION OF GENES CONTROLLING FIBER QUALITY IN COTTON. EUPHYTICA. 2001. V. 121. P. 163-172. Interpretive Summary: Cultivated cotton is a high-value-per-acre crop that is produced as raw material for the textile industry. The factors associated with increasing textile automation require greater precision and speed to make genetic changes in developing cotton cultivars of superior fiber quality. Classical cotton breeding has been successful in improving fiber quality through tedious process of selection based on strength and other propertie in advanced generations of selected lines. The use of DNA markers and new methods to measure the fiber quality allow cotton breeders to use greater precision to attack the problem. By use of several hundred DNA markers and an interspecific F2 population derived from a cross between an Upland genetic standard TM-1 and 3-79, an extra long staple (ESL) cotton, thirteen quantitative trait loci (QTLs) controlling fiber quality properties were identified, four QTLs bundle fiber strength, three for fiber length, and six for fiber fineness. These QTLs collectively explained 30% to 60% of the total phenotypic variance for each fiber quality property in the F2 population. For the fiber quality QTLs that were additive and recessive, marker-assisted selection would be very effective in cotton breeding programs. The linked DNA markers would also provide useful tools to compare the fiber quality genes' different genetic backgrounds.
Technical Abstract: Cotton (Gossypium spp) is the world's leading natural fiber crop. Genetic manipulation continues to play a key role in the improvement of fiber quality properties. By use of DNA-based molecular markers and polymorphic mapping population derived from an interspecific cross between TM-1 and 3-79, thirteen quantitative trait loci (QTLs) controlling fiber quality properties were identified in 3-79, an extra long staple (ESL) cotton. Four QTLs were responsible for bundle fiber strength, three for fiber length, and six for fiber fineness. These QTLs were located on different chromosomes or linkage groups, collectively explaining 30% to 60% of the total phenotypic variance for each fiber quality property in the F2 population. The effects and gene modes of the individual QTLs were characterized with 3-79 alleles in TM-1 genetic background. The results indicated that the genes are more recessive than dominant, with much less additive effect in the gene mode. Transgressive segregation was observed for fiber fineness that could be beneficial to improvement of this trait. Molecular markers linked to fiber quality QTLs would be most effective in marker-assisted selection (MAS) of these recessive alleles in cotton breeding programs.