Inter- and Intraspecific Competition between Invasive Taraxacum officinale and Native Taraxacum platycarpum

Abstract

Invasive species, Taraxacum officinale, is spreading around the world and threaten the native dandelion species. While invasive plants could have a negative effect on the native plants directly via resource competition, only few studies examined competition between invasive and native dandelions. In addition, given the production of apomixis seeds, invasive T. officinale might have the ability to distinguish genetically close individuals, so called kin recognition, and consequently reduce the intraspecific competition. For examining inter- and intraspecific competition, we collected seeds of invasive (T. officinale) and native (T. platycarpum) dandelion species from two distant sites (Incheon and Jeonju). Plants were grown in a greenhouse environment and seeds of the second generation were used for the experiment. Three different combinations of two dandelions were grown together in a single pot: kin (conspecific siblings), stranger (conspecifics from different sites), and interspecies. As a control, a single plant was grown in a pot. Half of plants were collected after one month of growth, and we measured the total biomass, leaf mass, root mass, root length, total leaf area and the length and width of the longest leaf. The other half of plants will be used to measure reproductive traits. We expect that invasive T. officinale are more competitive than native T. platycarpum. In addition, T. officinale is expected to recognize their genetically close individuals and reduce competitive traits, but T. platycarpum would not.