The tartary buckwheat (Fagopyrum tataricum) of Polygonaceae is amultipurpose plant, which originated in China. Because of the complexgeography of our country, there is abundance of resources of tartarybuckwheat. The evaluation of genetic background of germplasm is anessential step in plant breeding program. Most of reported researches aboutgenetic diversity of buckwheat were carried out from traditionalmorphologic facet, inter-species hybridize, or isoenzyme analysis. Howeverthe low natural hybridization rate of tartary buckwheat results in lowefficiency of conventional breeding methods which use mostly phenotypicaltraits in selection. With the development of molecular markers, more choicescould be selected.Microsatellite, also called simple sequence repeats (SSR), were widelyused as genetic markers because of being co-dominant, multiallelic, easilyscored and highly polymorphic.There were only 26 primers reported by former researchers whichdeveloped from common buckwheat by Konishi T. et al. These primers wereevaluated in this study using 23 tartary buckwheat varieties. The resultsshowed that there were just 4 primers could be used for polymorphism tests.3 primers were designed according to the sequences got from Genbank,but only 2 of these primers could be amplified using aforementionedsamples.The 5'-anchored PCR could be used to amplify the (GT/CA)n repeatsfrom total DNA of tartary buckwheat. The products ligated to pGEM-Tvector, and the reconbitants were transforred into DH5αcompetent cells toconstruct the library enriched with (gT)n repeats. The sequence analysis of 5insterts showd that they all contained microsatellites at both ends of theinsert, and each was unique. Four specific primers were designed accordingto the flanking sequence of loci, and 2 of which could be amplified.For long repeats screening, the Dynabeads? purification were added after the anchored PCR. The 5'-(GT)16-biotin were used here as a probe forhybridization. Sequencing analysis of 6 clones from library showed that, 4inserts could be accepted as a success, they all contained at least one (GT)nrepeats which n≥16, and the repeats number of another one was 15. Theycould possibly be used for detecting the polymorphism. |