*3.1. Data Source, DNA Extraction, and Sequencing*

For 10 buckwheat cultivars (Dasha, Dizajn, Demetra, Devyatka, Dialog, Bashkirskaya krasnostebelnaya, Karadag, Kujbyshevskaya, Kazanka Russian cultivars and Shinanonatsusoba Japanese cultivar) and *F. esculentum* ssp. *ancestrale*, the data were generated in this study. DNA was extracted using the cetyl

trimethylammonium bromide (CTAB)-based method [44] from a single plant (Dasha, *F. esculentum* ssp. *ancestrale*) or a pool of five plants (other cultivars). For Dasha cultivar, sequencing was performed using a Sequel II instrument (Pacific Bioscience, Menlo Park, California, USA) at DNALink company. For other cultivars (except for Koto) and *F. esculentum* ssp. *ancestrale*, libraries were prepared using a TruSeq DNA library prep kit (Illumina, San Diego, California, USA) and sequenced on a HiSeq2000 instrument. The reads are deposited in the NCBI database under bioproject number PRJNA627307. Koto sequence data were taken from the study [4], DRA accession number DRR046985.
