Morphological and Molecular Status of Daphne wolongensis C.D.Brickell et B.Mathew as Genetic Resource for Horticulture

Daphne wolongensis described on the basis of a few known individuals was investigated in the wild, in Wolong Valley, Sechuan. Its status of valid species was verified morphologically and genetically. Three newly found populations were compared to the closely related species Daphne retusa, D. tangutica, D. longilobata, D. acutiloba, D. sureil, to clones available in cultivation and selected cultivars. The high bootstrap values indicate a sufficient level of genetic differentiation between each of the studied species. The hypothesis of whether D. wolongensis is a hybridogenous species was rejected, it is a well-defined independent species. Based on morphological and genetic data, it seems possible that another species, D. limprichtii, can be a mountain form of D. tangutica. Variability of populations in Wolong gives a good opportunity to select genotypes with a higher or better performance of combination of traits. From 67 samples collected from Wolong, it was possible to select the top ten different types as genetic resources for breeding. Daphne wolongensis, in the visited sites of Wolong area, occupies less than 1 km(2). Together with isolated finds, the number of individuals is less than 500 and the area surveyed is not larger than 10 km(2), thus it falls into the IUCN category of Critically Endangered plants.