Background/Objectives: Stay-green proteins (SGRs) play a vital role in regulating plant chlorophyll degradation and senescence. However, this gene family has not been explored in Ipomoea species and sweet potato. Methods: A total of 19 SGR family genes (SGRs) were identified using Basic Local Alignment Search Tool (BLAST) methods. The proteins’ physiological properties, evolutionary and phylogenetic relationships, conserved domain and motifs, gene structures, collinearity, and promoter cis-elements were systematically analyzed. Moreover, expression patterns and protein interaction network analyses were performed for sweet potato. Results: In this study, we identified 19 SGRs in six Ipomoea species. These SGRs were divided into four subgroups according to their phylogenetic relationships. Domian analysis revealed that SGRs had the conserved “stay-green” domain. Gene structure analysis showed that SGRs had similar structures. The collinearity analysis revealed that the SGRs originated from two genes, with one gene undergoing duplication during evolution history; moreover, the SGRs experienced rearrangement throughout the evolutionary process in the Ipomoea species. Cis-elements related to pigment biosynthesis and hormone and stress responses were found. In addition, expression pattern analysis showed that IbSGRs, especially IbSGR1, IbSGR2, and IbSGR3, might play an important role in pigment accumulation. The SGRs could also respond to stress responses (i.e., cold, drought, and salt) and take part in hormone crosstalk (i.e., abscisic acid (ABA), methyl jasmonate (MeJA), salicylic acid (SA)). Conclusions: Taken together, the findings of this study provide new insights for further understanding the functions of SGRs and candidate genes for pigment accumulation and stress tolerance in sweet potatoes.

VOZ (Vascular Plant One-Zinc Finger) transcription factors represent a plant-specific family of regulatory proteins that are pivotal in controlling plant growth, developmental processes, and adaptive responses to biotic and abiotic stresses. Although VOZ genes have been reported in multiple plant species, their genomic organization, evolutionary history, and functional dynamics in sweet potato remain largely unexplored. In this study, a comprehensive genome-wide investigation of VOZ family members was conducted across six Ipomoea species, namely I. aquatica (Iaq), I. cairica (Ica), I. nil (Inil), I. triloba (Itb), I. trifida (Itf), and Ipomoea batatas (Ib). In terms of their phylogenetic relationships, protein properties, gene architecture, conserved motifs, promoter cis -elements, chromosomal localization, and collinearity patterns, 14 VOZ genes were identified and systematically analyzed. The findings reveal a contraction in VOZ copy number, accompanied by structural and functional divergence during the evolutionary trajectory of these Ipomoea species. Furthermore, transcriptional profiling and protein-protein interaction network characterization in sweet potato indicate that VOZs from I. trifida (ItfVOZs) and I. batatas ( IbVOZs ) are implicated in developmental regulation, hormone-mediated signaling pathways, and stress adaptation. Collectively, this study provides a comprehensive genomic framework for the VOZ gene family across six Ipomoea species and provides a solid foundation for elucidating their functional roles in sweet potato.