Study Of Seed Protein On Resources Of Genus Fagopyrum

The seed protein content (%) of 179 accessions involved 10 species of genus Fagopyrum were determined and the seed protein composition and its inheritance were studied. The results were as follows:1. There are significant differences of seed protein content among different accessions within the same species and among different species or different types (between cultivated common buckwheat and tartary buckwheat, between diploid and tetraploid buckwheat, between cultivated and wild types in the big-achene group buckwheat, and between the big-achene group and the small-achene group). Some excellent accessions with high seed protein content such as Sobano and F.esculentum var. homotropicum were discovered, helpful to buckwheat quality breeding.2. There are significant linear regression and correlation between the dye combination amount (x) and the protein content (y). The optimum conditions for determination of the seed protein content of buckwheat by the dye combination method in this study were: temperature 15℃, time 50min, and the dye concentration 0.06mg/mL. Under these conditions, cultivated common buckwheat and tartary buckwheat have different regression equations, that is, y=15.364x+3.865 and y=10.769x+6.287, respectively.3. Seed protein components of cultivated buckwheat were extracted by means of ultrasonic technique. The results showed that albumins content is the highest, globulins the second, and prolamines and glutelins the lowest.4. SDS-PAGE showed that among seed protein components of 10 accessions of common buckwheat and 10 accessions of tartary buckwheat the protein subunits bands of albumin and globulin are the richest, very similar to each other, and different from other seed protein components. For common buckwheat, the albumin and globulin subunits mostly locate the range of 55-75kDa, while for tartary buckwheat 58.4-63.7kDa. There are some differences on protein subunits of seed protein components within the same buckwheat species, but much less than those among different buckwheat species, which are useful on identification of the species or special varieties.5. The broad heritability and the narrow heritability of the seed protein content in cultivated buckwheat are 54.17% and 41.15%.