Wild edible plants and their cultural significance among the Zhuang ethnic group in Fangchenggang, Guangxi, China

Abstract Introduction Fangchenggang is situated in the Guangxi Zhuang Autonomous Region, China, renowned for its rich biodiversity and ethnically diverse population. The Zhuang people, constituting the largest minority group in the area, possess a wealth of traditional knowledge concerning wild edible plants (WEPs) owing to the region's favorable environment and dietary customs. With the rapid development of urbanization, tourism, and trade, the Zhuang people's food culture, including the consumption of wild edible plants, has become an attractive aspect of urban development. However, there is almost no comprehensive report available on WEPs consumed by the Zhuang people. The objectives of this study were to: (1) conduct a comprehensive ethnobotanical investigation of the WEPs among the Zhuang people in the region; (2) evaluate the cultural food significance index (CFSI) for the local communities; (3) summarize the cultural characteristics of the wild edible plants consumed, providing scientific support for the development of Fangchenggang as a sustainable and attractive tourism destination. Methods Ethnobotanical investigation including market surveys, semi-structured interviews, key informant interviews and participatory observations was conducted in Fangchenggang from January 2021 to March 2023. A total of 137 informants were selected using the snowball method. Information about WEPs, including vernacular names, food categories, parts used, mode of consumption, collecting season, and recipes, was collected and recorded. The CFSI (cultural food significance index) was calculated to identify the most culturally significant WEPs. Results A total of 163 species of wild edible plants consumed by the Zhuang people were identified, belonging to 67 families. The main categories of WEPs include wild vegetables (69) and tea substitutes (42). The most commonly consumed parts are fruits (37), followed by whole plants (33) and leaves (21), with herbaceous plants (74) being the most numerous. The availability of wild edible plants remains high throughout the year, with the peak seasons occurring in August and October, and significant abundance also noted in July and November. In the highly significant category (CFSI > 500), a total of 15 plant species were identified, which play a crucial role in the local diet. Additionally, 17 alien species have become part of the local consumption of wild plants, with 7 species listed as invasive alien species. Discussion and Conclusions This study documented 163 wild edible plant species and their associated traditional knowledge of the Zhuang people. The research identified culturally significant WEPs and analyzed their multiple uses. The historical development of wild plant consumption in Fangchenggang showed the strong influence of natural and social environments on the Zhuang ethnic group's dietary traditions. The WEPs are characterized by “sour food”, “fresh ingredients” and “cold dishes”, aligning with their health-oriented philosophy of “homology of medicine and food”. Future prospects encompass the cultivation of economically sustainable wild edible plants (WEPs), the preservation of their traits through cross-breeding, ensuring safe consumption through research and safety evaluations, and advocating for the preservation of WEPs' culinary culture to support tourism and sustainable urban development.