Breeding for Improved Germination Under Water Stress in the Russian Dandelion

The Russian dandelion (Taraxacum kok-saghyz Rodin) is a promising candidate for introducing natural rubber production into North America; however, the plant must be domesticated before it can be cultivated. Germination in Southwestern Ontario is only 10-30% due to a lack of adaptation for establishment on bare soil where water stress can occur. Phenotypic and half-sib family selection were compared for improving germination under low water potential, where seeds were incubated in a polyethylene glycol solution. After one cycle of half-sib or phenotypic recurrent selection, percent germination increased 128.5% and 2.8%, and time to 10% germination decreased 14.3% and 18.3%, respectively. Thus, recurrent selection has potential to improve germination under water stress in the Russian Dandelion, and half-sib family selection provided better overall gain compared to phenotypic selection. Additional breeding cycles and assessment of germination under field conditions will be critical for developing a method to improve this crop.