Ethnobotanical research on the plant dyes used by Baiyi people in Heqing, Yunnan

Plant dyes have the advantages of green environmental protection and high safety, but due to the shortage of resources, high cost and low color fastness, the industrial application of plant dyes is limited. Baiyi people have the traditional custom of plant dyeing in Heqing, Yunnan Province, and there are rich local dye plant resources and traditional dyeing technology. In order to investigate, record and study Baiyi people plant dyeing and related traditional knowledge, expand plant dye resources and promote the development and utilization of plant dyes, this study conducted ethnobotanical investigation on plant dyeing and related traditional knowledge of Baiyi people in Liuhe Yi Township, Heqing County, Dali Prefecture. From September 2019 to March 2020, 288 informants were interviewed by semi-structured interviews from four villages in Liuhe Yi Township, Heqing County, Dali Prefecture; local dye plants were investigated by field research; traditional plant dyeing crafts were recorded by participatory observation; traditional knowledge of plant dyeing was analysed through quantitative analysis (f value, CIIs value, ICF value). The results are as follows: (1) The Baiyi people use 11 species of dye plants in Heqing, belonging to 10 families and 11 genera. (2) People of different regions, ages and genders have different cognitions of traditional knowledge of plant dyeing. (3) The use frequency and cultural importance index of Viburnum cylindricum and Buddleja officinalis are higher, and the cognition of Baiyi people is highly consistent on dye plants of blue. (4) Baiyi people often use dye plants to dye their own traditional cloth (folk cloth made from Gerbera delavayi). This research reveals that Baiyi people have a relatively complete knowledge system of traditional plant dyeing in Heqing, but it has gradually lost with the development of the times. This study provides scientific clues for the exploitation of dye plant resources and the research of traditional plant dyeing technology, promotes the industrial application of dye plants of minority, and has a great significance and application value for the economic development in minority areas.