Genetic diversity amongst Australian canola cultivars determined by randomly amplified polymorphic DNA

Abstract

Summary. The rapid increase in canola production in Australia in recent years has been associated with the release of several new cultivars with progressive improvements in quality, yield and disease resistance. The origin of many Australian cultivars is Canadian material that was introduced into Australia in the late 1970s. A selection of new genetic material has recently been introduced from diverse sources including China, Japan and Europe. As a result, Australian cultivars now contain a much larger gene pool and wide ranging agronomic characteristics. Cultivar identification and discrimination has become an important issue in canola breeding programs.

This paper describes the diversity amongst 25 Australian cultivars, analysed using the polymerase chain reaction and arbitrary primers to detect randomly amplified polymorphic DNA (RAPD) sequences. From 19 primers, 89 bands were detected. Six of the best of these primers, producing 27 bands, were selected for cultivar discrimination. Cluster analysis was used to illustrate the diversity of genetic material in Australian canola cultivars and between individual breeding programs. Despite the common origin of Australian cultivars, differences between individual programs are evident.

The results obtained are generally in agreement with known pedigrees. However, RAPD provides canola breeders with a more accurate picture of similarities and diversity among cultivars. The similarity of cultivars within individual programs suggests RAPD discrimination may be associated with particular cultivar characteristics and able to be used in selections in breeding programs.