1. College of Life Sciences, Northwest A&F University , Yangling 712100 , China
2. Herbarium of Northwest A&F University , Yangling 712100 , China
3. College of Life Sciences, Tarim University , Alaer 843300 , China
4. College of Horticulture, Northwest A&F University , Yangling 712100 , China
5. College of Life Sciences, Shaanxi Normal University , Xi’an 710062 , China
6. Royal Botanic Garden Edinburgh , Edinburgh EH3 5LR , United Kingdom