关键词: 荞麦, 作物起源, 二型花柱, 药用价值, 长江流域, 野生种质资源, 系统发生学, 祖先种

Abstract

Buckwheat is a pseudo-cereal with high nutritional and officinal value, a food crop outside of Poaceae. Cultivated buckwheat includes two species: sweet or common buckwheat (Fagopyrum esculentum), a self-incompatible, distylous annual and bitter or tartary buckwheat (F. tartaricum), a self-compatible, homostylous annual herb; the former depends on insect pollination for seed production. Thirty species have been named in the genus Fagopyrum (Polygonaceae) in the world. Investigations of morphology and genetic diversity suggest that Southwest China is the diversity center of Fagopyrum, especially in the area of Three Parallel Rivers, the upper Yangtze River Valley, where ancestral species of the two buckwheat crops were originated. Previous studies of basic biology on the buckwheat crops are briefly summarized here. Future studies of the taxonomical revision on the genus Fagopyrum, collections of wild germplasm resources, exploration of the interspecific relationships and the breeding of cultivars with superior agronomic traits are strongly needed. Palynological and archaeological evidences imply that the buckwheat crop has been cultivated at least 4,500 years in the Yangtze River Valley, and might have ever been a main food for local populations in the mountain areas, providing food resource for emerging of Yangtze River civilization. Deep understanding of the basic biology of buckwheat with modern techniques of genomics could clarify the origin of cultivated buckwheat and factors limiting seed production. The buckwheat could be a superior crop in the mountain areas if the traits with high agronomic and medicinal value can be excavated and exploited.

Key words: Fagopyrum, crop origin, distyly, medicinal value, Yangtze River Valley, wild germplasm resources, phylogeny, ancestral species