Plant Genome IV Conference Plant Genome IV Conference
The genetic diversity among different Arabidopsis thaliana ecotypes has been estimated by molecular fingerprinting. The term "ecotypes" refers to a population that has maintained its identity through isolation or selection in a specific environment. Due to the low outcrossing rate and/or isolation of a population, any genetic variation between populations is rapidly fixed. So far we have analyzed the intra- and interspecific variation of 22 ecotypes by means of AFLP analysis and to a lesser extent using SSLP-markers. Both methods are highly reproducible and very useful for comparative fingerprinting: the AFLP technique has a high multiplex ratio, meaning that a large number of bands can be detected in a single reaction, while SSLP-markers are most informative because of the high length heterogeneity of the microsatelites. For each ecotype, genomic DNA of at least ten individual plants was primarily analyzed by AFLP using 11 primer combinations. Of all the bands obtained, 50 % was polymorphic among the different ecotypes. Genetic distances (GD) were estimated based on Jaccard s coefficient of similarity, cluster analysis was performed and expressed in a dendrogram. In a subsequent step, the different ecotypes were also analyzed with SSLP primers and the obtained results were compared with the AFLP data.