Submitted to: Alfalfa Improvement Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 7/27/2002
Publication Date: N/A
Technical Abstract: The overall objectives of this research are to 1) develop simple sequence repeat(SSR or microsatellite) DNA markers for use in mapping autotetraploid alfalfa (Medicago sativa L.), 2) to construct SSR based genetic maps of alfalfa where markers will be integrated with previously mapped AFLP and RFLP markers, 3) to identify markers associated with agronomically important quantitative and qualitative genes, and 4) to evaluate diversity and phylogenic relationships in Medicago sp. germplasm using selected SSR markers. Tri- and tetra-nucleotide SSR markers from alfalfa genomic clones and from ESTs of the closely related diploid Medicago truncatula, will be mapped initially to an 'ABI 408' purple flowered winter hardy X 'WisFal' yellow flowered population. In the initial phase of this project, 51 and 112 M. truncatula SSR markers identified by T. Huguet and N.D.Young, respectively were screened for mapping potential in the Brummer population as were 44 tri- and/or tetra-nucleotide SSRs from The Institute for Genomic Research's (TIGR) M. truncatula Gene Index that had not been identified in earlier evaluations by other institutes. Eleven of the Huguet primer pairs, 24 of the Young primer pairs, and 23 of the TIGR primer pairs yielded single dose responses in at least one allele and several primer pairs yielded four or more alleles with a single dose response. Primer pairs eliciting single dose responses will be retested with the parents and 100 F1s and analyzed for conformation to a 1:1 ratio. Those conforming to the Mendelian ratio will be mapped to the Brummer population as RFLP and AFLP markers are resolved.