*2.1. Retrieval of SOD Gene Family in Water Lily Species*

To investigate the *SOD* gene family in water lilies, the Blastp search method was employed, utilizing the *Arabidopsis SOD* sequence as a query to examine the entire genome of each water lily species individually [36]. In our study, we used two methodologies, protein blast and the hidden Markov model (HMM), to detect *SOD* genes in four water lily species in which the genome sequences of two species *Nymphaea colorata*, and *Nymphaea thermarum*, are available online; while the other two, i.e., *Nymphaea minuta*, and *Nymphaea mexicana*, have unpublished genome sequences. For BLASTP, we utilized eight *A. thaliana SOD* amino acid sequences (AT1G08830.1/*AtCSD1*, AT2G28190.1/*AtCSD2*, AT5G18100.1/*AtCSD3*, AT4G25100.1/*AtFSD1*, AT5G51100.1/*AtFSD2*, AT5G23310.1/*AtFSD3*, AT3G10920.1/*AtMSD1*, and AT3G56350.1/*At00MSD2*) as the query, with an e-value set to 1 × <sup>10</sup>−5. We obtained these eight *AtSODs* amino acid sequences from the *Arabidopsis* genome database TAIR (http://www.arabidopsis.org/ accessed on 5 January 2023). To identify conserved domains *SOD\_Cu* (PF00080), *SOD\_Fe\_C* (PF00081) and *SOD \_Mn* (PF02777), we performed scans of specific amino acid sequences using the web resources Pfam (Pfamv34.0-19178pSSMs) protein domain database (http://pfam.xfam.org/ accessed on 8 January 2023), and SMART (http://smart.embl-heidelberg.de/ accessed on 9 January 2023) [37].

#### *2.2. Analysis of Physicochemical Features and Subcellular Localization*

In order to anticipate the physicochemical characteristics of *SOD* proteins in water lily species, such as amino acid count (A.A), theoretical isoelectric point (pI), molecular weight (kDa), Pfam Domains, Functional annotations, and grand average of hydropathicity (GRAVY), we employed the ProtParam website accessible at http://web.expasy.org/ protparam/ accessed on 13 January 2023 [38]. In order to predict the subcellular localization of *SOD* proteins, we employed the WoLF PSORT (https://wolfpsort.hgc.jp/ accessed on 17 January 2023) [39] and ProtComp 9.0 server (http://linux1.softberry.com/ accessed on 18 January 2023) [27].
