Ethnobotany and nutritional components of Changmaogu, a rare and endangered rice landrace

Agrobiodiversity including landraces of crops is extreme significant for global food security and sustainable rural development but it is losing at alarming speed. Only in the remote areas, some of landraces are remained in local agroecosystem. Landraces refer to the traditional resources domesticated by people living in a certain area. They are bred or evolved in the local environments, which can adapt to the local natural and cultural environments. Changmaogu is a unique colored rice landrace planted by Lama people, a branch of Bai, in Lanping Bai and Pumi Autonomous County, Yunnan Province. Changmaogu is a typical representative landrace in China. Due to its lower yield, the cultivation of Changmaogu was controlled in a very limited area in the past few years, which was a very dangerous signal for a major crop. Despite its rare and endangered status, there has been a lack of research on Changmaogu. In order to promote the conservation and sustainable development of this landrace, we investigated and analyzed the quality traits, traditional knowledge and culture, development and utilization status and existing problems of Changmaogu in Lanping, and determined the nutritional components of Changmaogu comparing with those of common rice varieties to explore the nutritional value of Changmaogu, using the methods of ethnobotany and nutrition. The results are as follows: (1) The Lama people, have developed rich traditional knowledge about Changmaogu, including traditional farming knowledge, relevant historical allusions, traditional eating knowledge, seed exchange and conservation culture. They never use chemicals but collect green manures as fertilizer for this landrace. Under the backgrownd of understanding the good characteristics of Changmaogu, the local people continue to grow Changmaogu in the original habitat in a larger scale according to their traditional knowledge and culture. (2) Changmaogu has a high content of available carbohydrates, water, ash, total dietary fiber and anthocyanin, and contains a certain content of procyanidins, indicating that it has excellent nutritional and health care values. This study indicates that the mode of in-situ or on-farm conservation of Changmaogu provides a great reference for the conservation of other landraces, and reveals the fact that the outstanding properties like high nutritional value of Changmaogu will contribute to the sustainable uses of Changmaogu and other landraces.