Submitted to: Euphytica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/3/2006
Publication Date: 2/1/2007
Citation: Wu, J., Jenkins, J.N., McCarty Jr., J.C., Zhong, M., Swindle, M. 2007. AFLP marker associations with agronomic and fiber traits in cotton. Euphytica. 153:153-163. Interpretive Summary: Very little is known about the association of molecular markers with important quantitative traits for yield and fiber quality in cotton. Association of molecular markers with these important traits in wide crosses in cotton breeding should improve the process of using genes from exotic cottons in commercial cotton breeding. We determined the association of 119 AFLP molecular markers with seven agronomic and fiber quality traits among 20 day-neutral lines and parents derived from crosses of exotic cottons with cultivars. We found that more than 50 markers were significantly associated with the traits of lint yield, boll weight, lint percentage, and the fiber quality measurements of 2.5% span length, elongation, strength, and micronaire; however, one to four markers for each of the seven traits could explain from 22% to 93% of the phenotypic variability for each of the traits among the various lines. This implies that a few selected markers should be useful for marker assisted selection in breeding when the goal is to use genes from exotic day-neutral lines in crosses with cultivars in cotton breeding.
Technical Abstract: A marker linked with QTL can be a useful tool for cotton (Gossypium spp.) genetics and breeding. We crossed four photoperiodic accessions of cotton with a cultivar, selected day-neutral plants and backcrossed four times to the photoperiodic accession, selecting day-neutral plants in each generation. The day-neutral plants from the first cross and the four backcross generations were advanced to the F6. These 20 day-neutral lines and four cultivars were grown in two environments at Mississippi State, MS, and scored for agronomic and fiber quality traits. They were also scored for AFLP markers using a bulk sample of leaves from each line. More than 50 AFLP alleles were associated with the seven traits with fewer alleles associated with fiber than agronomic traits. However, one to four alleles were associated with 22% to 93% of the phenotypic variability of each of the seven traits. These results suggest that selected markers could be used in marker assisted selection in crosses designed to use alleles from exotic accessions to develop elite breeding lines for cotton improvement.