Ethnobotany of Local Vegetables and Spices in Sakon Nakhon Province, Thailand

Local vegetables and spices are essential components of traditional food and health systems in northeastern Thailand, yet quantitative ethnobotanical evidence remains limited. This study documents the diversity, utilization, and cultural significance of vegetables and spices used in Sang Kho Sub-district, Phu Phan District, Sakon Nakhon Province. Ethnobotanical data were collected in 2025 through field surveys, voucher-based plant identification, semi-structured interviews, and participant observation involving 92 informants across 23 villages. Cultural significance and medicinal knowledge were evaluated using the Cultural Importance Index (CI), Informant Consensus Factor (FIC), and Fidelity Level (FL). A total of 113 taxa belonging to 94 genera and 49 plant families were recorded. Poaceae and Zingiberaceae were the most species-rich families. Native species slightly predominated (51.33%), and herbaceous taxa were most common. Leaves were the most frequently used plant part. Most taxa were used as vegetables (92 species), followed by traditional medicines (20 species), spices or seasonings (18 species), and food ingredients or culinary additives (18 species). The highest CI values were recorded for Allium ascalonicum L. (1.152), Capsicum annuum L. (1.098), and Coriandrum sativum L. (1.043). FIC values ranged from 0.60 to 1.00, with complete consensus for circulatory and neurological disorders. Cymbopogon citratus showed the highest FL (75%) for gastrointestinal uses. These findings demonstrate the close integration of food and medicine in local plant-use systems and provide baseline data for food system resilience and cultural knowledge conservation.