GENETIC VARIABILITY AND RELATIONSHIPS AMONG 10 POPULATIONS OF RUBBER RABBITBRUSH (CHRYSOTHAMNUS-NAUSEOSUS SSP HOLOLEUCUS) DETERMINED BY RAPD ANALYSIS OF BULKED GENOMIC DNA SAMPLES

摘要

Chrysothamnus nauseosus (rubber rabbitbrush) has the potential to be an economically feasible crop. This plant produces significant quantities of secondary chemicals and is a large shrub able to grow in a wide range of environmental conditions. Ten geographically distinct populations of C. nauseosus ssp. hololeucus were analysed by random amplified polymorphic DNA (RAPD) analysis using bulked genomic DNA. A DNA extraction procedure was modified for use with C. nauseosus, and produced ample quantities of good quality DNA for RAPD analysis. Forty 10-mer random primers were used in the analysis of the bulked genomic DNAs. Of these primers, 24 produced RAPD bands in all populations. A total of 330 bands were scored. The banding patterns clearly mirrored the geographical grouping of the rabbitbrush populations, indicating that RAPD can be used in phylogenetic studies of Chrysothamnus. A high level of genetic variation was observed in these ten populations: 63.3% of the bands were polymorphic and 18.2% of the total bands were population specific. The high level of genetic variation could be used in breeding programs to increase the value of this shrub as a crop species. RAPD markers are easily identifiable and could be linked to important traits.