*5.1. Identification of XTH Gene Family in O. fragrans*

The whole genome of *O. fragrans* was obtained from the website http://117.78.20.25 5/ [35] (accessed on 17 March 2022). The protein sequences of *AtXTH* (*A. thaliana*) and *OsXTH* (*O. sativa*) were downloaded from the Ensembl Plants database (http://plants. ensembl.org (accessed on 17 March 2022)). Two programs of TBtools1.6 [36], Simple HMM Search and BLASTp, were used to identify *OfXTH* family genes. To be specific, the Simple HMM Search program was used to search the two XTH protein domains, PF00722 (ID: Glyco\_hydro\_16) and PF06955 (ID: XET\_C), from the database [37]. Thirtythree AtXTH proteins were used as queries to blast the *O. fragrans* genome database and identify XTH homologs in *O. fragrans*, with the parameters E-value < 10−<sup>15</sup> and identity > 50%. Only protein sequences present in both outcomes were regarded as OfXTH proteins and used for further analysis. SMART (http://smart.embl-heidelberg.de/ (accessed on 17 March 2022)) was used to check the conserved XTH domains Glyco\_hydro\_16 and XET\_C with default parameters. The ProtParam tool of online software Expasy (http: //web.expasy.org/protparam/ (accessed on 17 March 2022)) was used to determine the physicochemical parameters of OfXTHs protein sequence. SignalP 4.1 Service (http://www. cbs.dtu.dk/services/SignalP-4.1/ (accessed on 17 March 2022)) was used to predict the signal peptide. Plant-mPLoc (http://www.csbio.sjtu.edu.cn/bioinf/plant-multi/ (accessed on 17 March 2022)) was used to predict the sub-cellular localizations.
