Submitted to: Journal of Heredity
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/20/2001
Publication Date: 2/20/2002
Interpretive Summary: Mutants of cotton are plants that differ from normal in an observable manner, and they are used in studies of plant development, genetic mapping, and occasionally have proven to have agronomic value. The utility of mutants is enhanced when we know their genetic location. Genetic material is arranged on pairs of chromosomes, and cotton has 26 pairs of chromosomes. We have developed a series of cotton lines in which one of a pair or part of a pair of a specific chromosome is missing. Through the use of these lines, we can make test matings with the mutants to reveal which chromosome pair harbors the mutant. In these experiments, we tested six mutants with 34 of these special cotton lines, and we were able to assign a genetic location for three of them. The remaining three reside somewhere for which we did not have a represented chromosome pair in the test. Further tests with additional lines will be required to find their location.
Technical Abstract: Genetic mutants are useful tools for basic and applied research to elucidate the developmental and regulatory processes of the cotton plant (Gossypium hirsutum L.). Their value is enhanced with knowledge of their location in the genome. The results of aneuploid tests used to locate mutant loci on specific chromosomes in 18 of the 26 chromosomes, were used in combination with six mutants that were associated with nine loci. The mutant loci were glandless stem and boll (gl1gl6,), immature fiber (im), Ligon lintless-2(Li2), methylation (me), nonpinking (np1np2), and Raimondal (Ra1Ra2). We found that im was associated with chromosome 3 that contains linkage group VI (accessory involucre and frego bract); Li2 was associated with chromosome 18 that contains linkage group XVI (open bud and yellow pollen-2); and me was associated with chromosome 9. The remaining three mutants were not assoicated with the aneuploids in the tests. Knowledge of these chromosome assignments provides a valuable reference for specific studies of mutants and for further genome mapping efforts.