Phylogenetic relationship of four new species related to southwestern Sichuan Fagopyrum based on morphological and molecular characterization

Recently, four wild Fagopyrum species, Fagopyrum crispatifolium J. L. Liu, Fagopyrum pugense T. Yu, Fagopyrum qiangcai D. Q. Bai and Fagopyrum wenchuanense J. R. Shao, have been identified and described based on their morphological characters. This study investigates the phylogenetic relationship, nucleotide sequence polymorphisms of internal transcribed spacers (ITSs) and the maturase K (matK) gene within four wild species related to western Sichuan buckwheat. F. wenchuanense is closely related to Fagopyrum gracilipes while F. qiangcai is closely related to Fagopyrum esculentum based on their morphological differences. However, F. wenchuanense is more closely related to Fagopyrum cymosum and F. qiangcai is closer to Fagopyrum lineare and Fagopyrum leptopodum from the viewpoint of the ITS, and matK analysis. In addition, F. gracilipes is closer to F. pugense and Fagopyrum crispatofolium than to F. qiangcai. F. wenchuanense belongs to the cymosum group, while F. qiangcai, F. pugense and F. crispatifolium are classified into the urophyllum group based on their morphological and molecular analysis. Conducting morphological and molecular studies provide a better understanding of evolutionary mechanisms and genetic relationships of cultivated and wild buckwheat in western Sichuan, China.