|Guill, Katherine - Kate|
Submitted to: Journal of Theoretical and Applied Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/15/2000
Publication Date: 3/1/2001
Citation: MA, X., WANOUS, M.K., HOUCHINS, K.E., GOICOECHEA, P.G., WANG, Z., GUSTAFSON, J.P. MOLECULAR LINKAGE MAPPING IN RYE (SECALE CEREALE L.). JOURNAL OF THEORETICAL AND APPLIED GENETICS. 2001. V. 102(4). P. 517-523. Interpretive Summary: The ability of scientists to be able to produce genetic maps to estimate linkage distance between molecular markers in rye has limited our understanding of the relationships between rye and other cereals. The present study was initiated to ascertain the genetic location of molecular markers from rye, wheat, barley, oats, and rice to a common rye mapping population to study the relationships between the cereals and to understan if hot and cold spots of recombination exist throughout the rye family. The molecular markers were mapped to a linkage map using standard mapping procedures. We found out that the markers tended to form distinct hot and cold spots of recombination that were consistent in several ryes. Also, our mapping of markers from several cereal species was in agreement with the marker order observed in other species genetic maps. This information will be important to small grain researchers in their attempts to understand the genetic relationships among rye and other small-grain cereals by comparative genetic mapping, and to other plant scientists who will try to design more efficient crop plants through either classical breeding or biotechnology.
Technical Abstract: A rye linkage map was created containing clones from rye genomic libraries created at Columbia, Missouri, USA; Hannover, Germany; and Madrid, Spain; and wheat, barley, and oat genomic and cDNA clones. The F2 population consisted of 110 F2-derived F3 families. As rye-rye translocations are common, each F2 plant was analyzed by C-banding in order to establish its chromosome structure. All data were analyzed using the JoinMap program at a LOD score of 3.0 and the Kosombi mapping function. Both co-dominant and dominant markers were added to the map. Of all probes screened, 24.7% were polymorphic and mappable. Several conclusions can be made from the existing data. First, a relatively high level of segregation distortion was present, which is due to the outcrossing nature of rye. Second, markers inherited as dominant markers were not very compatible for mapping in combination with co-dominant markers. Third, only one interstitial cytological C-band (C1-1RS) was mapped. Fourth, it was established that the cM distance observed on the map was related to only that map and the parents used in creating the mapping population. When using the same markers on a different mapping population, different cM distances were observed. The present map contains 184 markers in seven linkage groups covering 727.5 cM. This places a marker about every 3.97 cM throughout the rye genome.