Author
KARAKAYA, HUSSEIN - CLEMSON UNIVERSITY | |
TANG, YUHONG - CLEMSON UNIVERSITY | |
Cregan, Perry | |
KNAP, HALINA - CLEMSON UNIVERSITY |
Submitted to: Journal of Theoretical and Applied Genetics
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 3/20/2002 Publication Date: N/A Citation: N/A Interpretive Summary: One use of genetic maps is to identify DNA markers in close proximity to functioning genes. These markers can subsequently be used in marker assisted selection to develop new crop cultivars or for the isolation of specific genes. In order to make genetic maps maximally useful it is important to position as many functioning genes as possible on such maps. The positioning of functioning genes provides important information about the structure and organization of plant genomes and facilitates the study of gene function. The spontaneous fasciation mutation (f) has a large effect upon stem development and reproduction of soybean and is encoded by a recessive allele at a single locus. Using a set of simple sequence repeat (SSR) markers specific to soybean linkage group D1b, we were able to position the gene controlling fasciation in a very specific region of the D1b linkage group. Knowledge of the genome position of the f locus will permit further investigation as to how this gene acts to control the growth of the soybean plant and how it interacts with other genes that control soybean development and reproduction. This basic genetic knowledge will be of use to other scientists studying the organization of the soybean genome as well as scientists investigating molecular mechanisms affecting soybean ontogeny. Technical Abstract: The spontaneous fasciation mutation (f) generates new developmental diversity in cultivated soybean, Glycine max (L.) Merrill. Strong apical dominance in the mutant inhibits axillary buds, causes branchless phenotype, and restricts reproduction to shoot apices. The fasciation mutation is encoded by a recessive allele at a single locus. The mutation, despite its importance in soybean development, has no locus assignment on the previously reported molecular maps in soybean. A population of 70 F2 progeny was derived from a cross between 'Clark63' and the fasciation mutant. More than 700 markers (RFLP markers derived from genomic clones and cDNAs, RAPD AFLP and SSR markers) were used in molecular mapping of the fasciation phenotype. Twenty linkage groups corresponding to the linkage groups of the public soybean molecular map are represented on the Clark63 x fasciation mutant molecular map that spans 3050 cM. The f locus was positioned on the linkage group D1b+W and linked with two AFLP and four SSR markers (Satt005, Satt141, Satt600, Satt703). The known map position of the f locus and demonstration of the mutant phenotype from early post-embryonic throughout reproductive stage provide an excellent resource for investigations of molecular mechanisms affecting soybean ontogeny. |