Soil physico-chemical properties on the distribution of Rhododendron species in China
Shusheng Wang graduated from Huazhong Agriculture University, Faculty of Life Science and Technology, in 2007. Since then, he has been working at the Lushan Botanical Garden, Chinese Academy of Sciences, on the conservation of wild Rhododendron species and breeding for new cultivars. He has been studying for his PhD since 2016 at the Flanders Research Institute for Agriculture, Fisheries and Food (ILVO) cooperating with Ghent University. Rhododendron is one of the most important ornamental plant genera encompassing nearly 1000 species. The majority of Rhododendron species occur in China. Rhododendrons are typically calcifuges that cannot grow well in lime soils. Shusheng Wang’s PhD research focused on screening and physiological characterization of lime tolerance in Rhododendron. As an important part of the PhD research, he investigated the effects of soil physico-chemical properties on the distribution of Rhododendron species in China, based on herbarium specimen and geochemical data. The herbarium specimen data were retrieved from the Chinese Virtual Herbarium. For more than 30,000 specimens, detailed information on location was present, which allowed geocoding into GPS data. Data on soil properties were present in the Harmonized World Soil Database (HWSD). Finally, the GPS data were linked to the distribution of 31,146 specimens and 525 taxa of Rhododendron to 60 soil units defined in the HSWD. Soil physical properties, such as gravel content, sand/silt/clay fraction, bulk density, and chemical properties like organic carbon content, pH, cation exchange capacity, base saturation, total exchangeable bases, calcium carbonate, sodicity and salinity in each soil unit and their correlation with the number of specimens and species were analysed. The results indicated that Haplic Luvisol (LVh) is the dominant soil unit for the distribution of Rhododendron species. Six soil units with more than 2000 specimens were Haplic Luvisols, Chromic Cambisols, Haplic Acrisols, Haplic Alisols, Cumulic Anthrosols, and Humic Acrisols with 9878, 2931, 2917, 2791, 2719 and 2019 specimens, respectively. The results showed that pH is one of the main properties that affect the distribution of Rhododendron species. The distribution maps of six soil units with the most specimens in China were generated. These data provide information that is useful for Rhododendron breeding programs and enable the identification of interesting species adapted to specific soil physico-chemical properties.
Shusheng Wang won an ISHS Young Minds Award for the best oral presentation at the XXVI International Eucarpia Symposium Section Ornamentals: Editing Novelty in Germany in September 2019.
Shusheng Wang, Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Plant Sciences Unit, Melle, Belgium, e-mail: firstname.lastname@example.org
The article is available in Chronica Horticulturae