Analysis On Genetic Diversity Of Chinese Buckwheat Cultivars

Buckwheat, originated from China, is widely planted in many countries over the world. It belongs to Fagopyrum Gaerth of Polygonaceae, which includes two cultivated species, Common buckwheat and Tartary buckwheat. Due to its great nutrient value and unique medical value, experts predict that buckwheat will become an important crop in the new . century.The genetic diversities of Chinese common buckwheat cultivars and tartary buckwheat cultivars from different regions were evaluated in morphology, cytology, biochemistry, and molecular marker. The main results obtained as follow:1) The six agronomic characteristics of buckwheat cultivars varied greatly on the extreme value and variant coefficient, which include days to mature, plant height, plant branch,node number of branch, seeds weight per plant, and 1000-kernel weight. Compared to tatary buckwheat cultivars, common buckwheat cultivars have richer agronomic characteristicses. According to difference of agronomic characteristicses, fifteen common buckwheat cultivars studied could be divided into five groups and sixteen tartary buckwheat cultivars studied could be divided into four groups.2) Buckwheat cultivars have the karyotype 2n=2x=16. The differences on the relative length of chromosome, the length ratio of chromosome, and satellite chromosomes among different species were much greatly than among in the cultivars.3) The zymogram of α -esterase, β -esterase and peroxidase of buckwheat cultivars have the rich polymorphism bands.The genetic similarity coefficient of buckwheat cultivars isoenzymes varied greatly,but the mean genetic similarity coefficient is little. Compared to common buckwheat cultivars, tartary buckwheat cultivar have the abundant zymogram diversity. Based on the genetic difference of buckwheat cultivars isoenzymes, fifteen common buckwheat cultivars were divided into four groups and sixteen tartary buckwheat cultivars were divided into five groups.4) The protein zymogram of common buckwheat have the abundent polymorphism bands,but tartary buckwheat cultivars display conformably in protein zymogram. The protein genetic similarity coefficient of common buckwheat cultivars varied greatly,while the average value of that is little. According to protein analysis,fifteen common buckwheat cultivars weredivided into five groups.5) Buckwheat cultivars have the high proportion of polymorphism bands and the little mean value of genetic similarity coefficient in the RAPD,compared to common buckwheat cultivars, tartary buckwheat cultivars have the rich diversity in this aspect. According to RAPD analysis, thirteen common buckwheat cultivars were divided into six groups and nine tartary buckwheat cultivars were divided into four groups.