Life‐history monographs of Japanese plants 14: Cardamine leucantha (Tausch) O. E. Schulz (Brassicaceae)

Abstract

AbstractThe life‐history characteristics of Cardamine leucantha (Tausch) O. E. Schulz (Brassicaceae) are described. The species is an herbaceous perennial that favors open but relatively moist habitats. It is distributed from Kyushu to Hokkaido in Japan but also occurs in Korea, Mongolia, China and the Russian Far East. In southwestern Japan, shoots start sprouting from mid‐ to late April, reaching approximately 30–70 cm in height, with 5–10 compound leaves. Ramets simultaneously produce one or more stoloniferous rhizomes that elongate until new ramets are formed at the tips. Cardamine leucantha has a pseudo‐annual life cycle, in which mother ramets wither at the end of each season and only daughter ramets appear aboveground in the next year. As a result, ramet positions change annually. In a study population, the number of flowers averaged 23.9 ± 21.0 per ramet and fruit set was 44.2 ± 24.8% (10.4 ± 10.1 fruits per ramet). Ramets produced 3.8 ± 2.3 rhizomes that were 22.0 ± 15.6 cm long. The species sometimes forms large populations. A single genet develops into a group of disconnected ramets spreading via clonal growth. Reproductive characteristics (e.g., fruit set and numbers of flowers and rhizomes) vary among populations, resulting in interpopulation differences in genet structure. Because the reference genome became available recently, established molecular tools will be applied effectively for the investigations of C. leucantha as a model clonal plant.