|Santos, C - EMBRAPA, BRAZIL|
Submitted to: Information Technologies Conference Proceedings
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: December 20, 2001
Publication Date: N/A
Interpretive Summary: Molecular markers have been widely used for genetic fingerprinting, genome mapping and estimating genetic variability. One such marker, AFLP is rapid and reliable but for large-scale, locus-specific application it requires fairly sophisticated equipment and training, relatively high costs, and a general requirement of radioactivity. This study found that most of the AFLP markets from two unrelated carrot populations were useful in teaching the same genes. This information is useful to researchers evaluating carrot genes in that it demonstrates that AFLP markers can be used equally well in unrelated carrot populations.
Technical Abstract: Amplified fragment length polymorphism (AFLP) is a fast and reliable tool to generate a large number of DNA markers. In two unrelated F2 populations of carrot (Daucus carota L.), Brasilia x HCM and B493 x QAL (wild carrot), it was hypothesized that DNA 1) digested with the same restriction endonuclease enzymes and amplified with the same primer combination and 2) sharing the same position in polyacrylamide gels should be conserved sequences. To test this hypothesis AFLP fragments from polyacrylamide gels were eluted, reamplified, separated in agarose gels, purified, cloned and sequenced. Among thirty-one paired fragments from each F2 population, twenty-six had identity greater than 91% and five presented identity of 24% to 44%. Among the twenty-six conserved AFLPs only one mapped to different linkage groups in the two populations while four of the five less-conserved bands mapped to different linkage groups. Of nine SCAR (sequence characterized amplified regions) primers tested, one conserved AFLP resulted in co- dominant markers in both populations. Screening among 14 carrot inbreds or cultivars with three AFLP-SCAR primers revealed clear and polymorphic PCR products, with similar molecular sizes on agarose gels. The development of co-dominant markers based on conserved AFLP fragments will be useful to detect seed mixtures among hybrids, to improve and to merge linkage maps and to study diversity and phylogenetic relationships.