Analysis of wild Taraxacum bicorne Dahlst. (Compositae-Crepidinae) as a potential alternative natural rubber crop

摘要

Taraxacum koksaghyz Rodin, a dandelion from the steppes of south-eastern Kazakhstan, has been known for long time as potential rubber producer, as a temperate region alternative to the tropical rubber tree Hevea brasiliensisMull. Arg.. In this work, we evaluate Taraxacum bicorne Dahlst. (wild populations), a closely related congener of T. koksaghyz. The taxonomy of T. bicorne is reviewed, population genetic characteristics are analysed by Simple Sequence Repeat markers, and rubber biosynthesis genes are identified by Kompetitive Allele Specific PCR. Rubber content of T. bicorne plants collected in wild is measured using a modified extraction method to minimize amount of material. Taraxacum bicorne is shown to be an outcrossing sexual diploid. Its rubber content is about half of that of T. koksaghyz (similar to 3.2% vs.similar to 7.2% of root dry weight), but T. bicorne could be used as a potential rubber source or as a source of germplasm for production of hybrids to improve rubber yield in various environments, because T. bicorne has considerable genetic variation, wider geographical range than T. koksaghyz and grows in different environments.