EVALUATION OF DIFFERENT MICROSATELLITE MOTIFS FOR ANALYZING GENETIC-RELATIONSHIPS IN CULTIVATED SUNFLOWER (HELIANTHUS-ANNUUS L.)

A total of 16 different simple sequence repeat motifs and an M13 repea t sequence were used as hybridization probes in order to examine the m olecular relationships between two German inbred and eight North Ameri can sunflower lines of known pedigree, and to determine the suitabilit y of the individual short tandem repeats for genetic analyses and thei r occurrence in the sunflower genome. Only the oligonucleotides (ACA)( 6), (CAT)(6), (CATA)(5), (GACA)(4) and (GATA)(4) proved to be well sui ted for the generation of scorable fingerprinting patterns, while the other (microsatellite) sequences were either too abundant or too rare. Although different levels of polymorphism were present in hybridizati ons with the different simple sequence repeats (SSRs), a clear separat ion of the German material from the USDA lines was feasible not only b y evaluating 20 probe-enzyme combinations, but also by combining every individual probe with four different restriction enzymes. In the Amer ican material, the expected relationships could be proved with the sin gle exception of a line that did not group in accordance with its pedi gree.