**2. Material and Methods**

### *2.1. Identification of wbm-*Like *Gene*

To identify the *wbm* location on a wheat chromosome, a 75-amino acid (aa) sequence of *wbm* protein [11] was employed as a query for tBLASTn search against the expressed sequence tags (EST) collection of NCBI, and an EST clone (BQ606004.1, https://www.ncbi.nlm.nih.gov/nuccore/BQ606004.1/) was found. This EST has a 225-base pair (bp) open reading frame predicted by ORFfinder (https: //www.ncbi.nlm.nih.gov/or ffinder/), and the corresponding protein sequence was identical to original *wbm* protein. Using this EST sequence, we next conducted a nucleotide BLAST search against the IWGSC RefSeq v1.0 ([21]) reference genome assembly of wheat Chinese Spring (https://urgi.versailles. inra.fr/blast/, [22]) and the NCBI WGS database.

### *2.2. Multiple Alignment of wbm and Related Protein and Nucleotide Sequences*

To compare *wbm* and *wbm-like* with the related sequences from other species and cultivars nucleotide BLAST [23] was performed against the latest assembly of their genomes (wheat cultivars: https://wheatis.tgac.ac.uk/grassroots-portal/ [24], http://www.10wheatgenomes.com/; *S. cereale*: https://webblast.ipk-gatersleben.de/ryeselect/, other species: https://plants.ensembl.org/ Triticum\_aestivum/ [25], https://urgi.versailles.inra.fr/blast/blastresult.php) using default parameters. The *wbm*-similar sequences were retrieved, and open reading frames (ORFs) were predicted using ORFfinder software (https://www.ncbi.nlm.nih.gov/or ffinder/). Corresponding ORF sequences overlapping with *wbm* hits and deduced protein sequences were aligned by ma fft [26] with standard parameters and visualized using UGene (Version 33, UNIPRO, LLC, Novosibirsk, Russia,) [27].
