Association of Grain Shedding Habit with Polyploidy in Tartary Buckwheat (Fagopyrum tataricum) Strains

Abstract

Sixty tartary buckwheat (Fagopyrum tataricum) strains were investigated for grain shedding habit, plant height, grain yield, dry weight of plant, weight of grain, days to flowering after sowing and DNA content of nuclei. The grain shedding habit was evaluated from the breaking strength of pedicel and the percentage of the grains dropped by threshing. DNA content of nuclei was detected by flow cytometry to classify the polyploidy level. The fluorescence intensity of the flow cytometry demonstrated no difference between common buckwheat (F. esculentum) and tartary buckwheat, but a clear difference was detected between the diploid and the autotetraploid strains. The survey of DNA content of the 60 tartary buckwheat strains revealed that most of the strains were diploids, but one strain was autotetraploid. The autotetraploid strain exhibited less grain shedding, and produced the largest grains among the strains tested. However, the other characters of the autotetraploid strain, such as plant height, grain yield, dry weight of a plant, and days to flowering, were similar to the mode of the traits of the diploid strains.