Plant & Animal Genome VI Conference

P60

ANALYSIS IN BRASSICA

1. Institute of Plant Genetics and Crop Plant Research (IPK), Corrensstr. 3, 06466 Gatersleben, Germany
2. Resistenzlabor der Saaten-Union OHG, Hovedisser Str. 92, D-33818, Leopoldshöhe, Germany

Microsatellite markers were developed as a rapid, efficient system for genome analysis and use in breeding programs of Brassica. Microsatellites are highly variable in repeat numbers and have a co-dominant inheritance. Approximately 100 microsatellite markers were isolated. The number of dinucleotide repeats ranged from 8 to 47. About 80% of developed microsatellites were polymorphic for Brassica napus. 70% of the microsatellite markers detected two loci in oilseed rape. 61 Brassica microsatellite markers detecting 198 alleles were used to estimate the extend genetic diversity among 34 B. napus varieties. On average 4 polymorphisms per microsatellite marker were observed. The data of microsatellites were compared with those of RFLPs in the same material. It is of particular interest to observe that the data of 61 MS markers consisted the data derived from using 226 RFLP probes detecting more than 800 polymorphisms. Both RFLPs and microsatellites showed nearly the same level of polymorphisms. By using the SSR markers in a cluster analysis, could be clearly distinguished between spring and winter type of oilseed rape. The estimated genetic distances for the B. napus lines with the lowest and for those with the highest distances confirmed the RFLPs data. Correlation between genetic distances estimated by MS and seed yield and those of RFLPs and heterosis for seed yield was nearly the same and highly significant.