1 Introduction

Sweet potato (Ipomoea batatas L.) is a crucial crop globally, ranking as the sixth most important food crop worldwide (Alam, 2021; Escobar-Puentes et al., 2022). It is particularly significant in regions such as China, which leads its production in a global market valued at USD 45 trillion (Escobar-Puentes et al., 2022). The crop's versatility and nutritional richness make it indispensable for food security, especially in developing countries. Sweet potatoes are rich in essential nutrients, including vitamins, minerals, and bioactive compounds, which contribute to their health benefits and their role in preventing malnutrition (Sun et al., 2014; Alam, 2021). Additionally, sweet potatoes are known for their drought tolerance, making them a reliable food source in areas prone to climate variability and water scarcity (Motsa et al., 2015).

Understanding the genetic basis of sweet potato adaptation is critical for enhancing its resilience and productivity. Genetic adaptation mechanisms enable the crop to thrive in diverse environmental conditions, which is essential for maintaining food security in the face of climate change (Motsa et al., 2015; Lamaro et al., 2022). Research has shown significant genetic variability in sweet potato genotypes, which affects traits such as yield, disease resistance, and nutritional content. By exploring these genetic factors, scientists can develop improved sweet potato varieties that are more resistant to diseases, such as the sweet potato viral disease (SPVD), and better suited to different agro-climatic zones (Lamaro et al., 2022). This knowledge is vital for breeding programs aimed at increasing the crop’s resilience and nutritional value.

This paper explores the genetic basis of sweet potato adaptation by reviewing the current knowledge of its genetic diversity and how it influences phenotypic traits. It investigates the mechanisms of sweet potato adaptation to various environmental stresses (e. g., drought and disease resistance) while identifying key genetic markers associated with target traits that can provide guidance for breeding programs, and also discusses the significance of genetic research in improving sweet potato varieties with the expectation of enhancing food security and improving nutritional outcomes.

2 Genetic Diversity and Evolutionary Background

2.1 Origin and domestication of sweet potato

The sweet potato (Ipomoea batatas) was domesticated in Central and South America before being introduced to Africa, where it is now widely cultivated across tropical regions (Glato et al., 2017). The domestication process involved significant genetic changes, including the integration of Agrobacterium T-DNA sequences into the sweet potato genome, which suggests that plant-microbe interactions played a crucial role in its domestication. This natural genetic modification may have provided traits that were selected for during the domestication process, highlighting the complex evolutionary history of this crop (Kyndt et al., 2015).

2.2 Genetic diversity among different cultivars

Genetic diversity in sweet potato varies significantly across different regions and cultivars. For instance, in West Africa, genetic diversity is structured into five distinct groups, each associated with specific climatic conditions and morphological traits (Glato et al., 2017). Similarly, a study in Puerto Rico revealed high levels of genetic diversity among local landraces, commercial cultivars, and accessions from the USDA repository, indicating a rich genetic pool that can be leveraged for crop improvement (Rodríguez-Bonilla et al., 2014). The genetic variability among sweet potato genotypes is also evident in traits such as tuber yield, carotene content, and vine length, which are crucial for effective crop improvement (Solankey et al., 2015).

2.3 Evolutionary traits that have enabled adaptation

Several evolutionary traits have enabled the sweet potato to adapt to diverse environmental conditions. The presence of Agrobacterium T-DNA sequences in the sweet potato genome is a notable example, as these sequences are expressed and may confer advantageous traits that were selected during domestication (Kyndt et al., 2015). Additionally, the genetic diversity structured along climatic gradients in West Africa suggests that certain genetic groups are better adapted to specific environmental conditions, such as tropical humid or Sahelian climates (Glato et al., 2017). The ability of sweet potato to thrive under different climatic conditions is further supported by the identification of expression quantitative trait loci (eQTLs) that regulate gene expression in storage roots, which can influence key agronomic traits (Zhang et al., 2020). These evolutionary adaptations highlight the sweet potato’s resilience and potential for further genetic improvement to enhance climate resilience and food security (Hancock, 2005; Pironon and Gomez, 2020).

3 Genomic Tools and Resources

3.1 Advances in sequencing technologies for sweet potato

Recent advancements in sequencing technologies have significantly enhanced our understanding of the sweet potato genome. High-throughput sequencing methods, such as Illumina paired-end RNA-Sequencing, have been employed to generate comprehensive transcriptomic data. For instance, Illumina sequencing produced 48.7 million 75 bp paired-end reads, which were de novo assembled into 128 052 transcripts, providing a robust resource for gene expression analysis in sweet potato (Tao et al., 2012). Additionally, single-molecule real-time sequencing has been utilized to identify full-length cDNAs and alternative splicing events, further enriching the genomic data available for this hexaploid crop (Ding et al., 2019). These technologies have enabled the identification of numerous differentially expressed genes and alternative splicing events, which are crucial for understanding the genetic basis of traits such as stress tolerance and metabolic processes (Ding et al., 2019; Arisha et al., 2020).

3.2 Overview of available genomic databases and resources

The accumulation of sequencing data has led to the development of extensive genomic databases and resources for sweet potato. For example, the de novo transcriptome assembly from Illumina sequencing has provided a comprehensive set of annotated transcripts, including those involved in viral genomes, starch metabolism, and stress responses (Tao et al., 2012). Furthermore, genome-wide analyses have identified a vast number of single nucleotide polymorphisms (SNPs) and expression quantitative trait loci (eQTLs), which are essential for dissecting the genetic regulation of gene expression in sweet potato (Zhang et al., 2020). The availability of these resources facilitates the cloning and identification of genes of interest, thereby accelerating research in sweet potato genomics and breeding (Tao et al., 2012; Zhang et al., 2020).

3.3 The role of bioinformatics in genetic analysis

Bioinformatics plays a pivotal role in the analysis and interpretation of the vast amounts of genomic data generated from sequencing technologies. Tools such as Blast2GO have been employed to annotate transcripts, linking them to gene ontology (GO) terms and KEGG pathways, which helps in understanding the functional roles of genes (Tao et al., 2012). Additionally, bioinformatics approaches are crucial for identifying and characterizing alternative splicing events, transcription factors, and non-coding RNAs, as demonstrated in studies utilizing single-molecule real-time sequencing (Ding et al., 2019). The integration of bioinformatics with genomic data allows for the construction of regulatory networks and the identification of master regulators, such as IbMYB1-2, which is involved in anthocyanin biosynthesis in sweet potato storage roots (Zhang et al., 2020). These analyses are essential for uncovering the genetic architecture underlying important agronomic traits and for guiding molecular breeding efforts (Tao et al., 2012; Ding et al., 2019; Zhang et al., 2020).

4 Key Genes and Pathways Involved in Adaptation

4.1 Identification of genes associated with abiotic stress tolerance (e.g., drought, salinity)

Recent studies have identified several key genes that enhance abiotic stress tolerance in sweet potato. The IbBBX24-IbTOE3-IbPRX17 module has been shown to improve tolerance to salt and drought stresses by scavenging reactive oxygen species (ROS) (Figure 1). Overexpression of these genes results in higher peroxidase activity and lower H₂O₂ accumulation, which are critical for stress response (Zhang et al., 2021). Another significant gene, IbMIPS1, enhances salt and drought tolerance by up-regulating genes involved in inositol biosynthesis, phosphatidylinositol (PI) and abscisic acid (ABA) signaling pathways, and the ROS-scavenging system (Zhai et al., 2016). Additionally, the overexpression of the betaine aldehyde dehydrogenase (BADH) gene from spinach in sweet potato has been shown to improve tolerance to multiple abiotic stresses, including salt, oxidative stress, and low temperature, by increasing glycine betaine (GB) accumulation (Fan et al., 2012). The ItfWRKY70 gene from Ipomoea trifida also plays a crucial role in drought tolerance by regulating ABA biosynthesis, stomatal aperture, and activating the ROS scavenging system (Sun et al., 2022).

Figure 1 IbPRX17 overexpression enhances salt and drought tolerance in sweet potato (Adopted from Zhang et al., 2021) Image caption: (a) Responses of IbPRX17-OE and wild-type (WT) sweet potato plants grown for 4 wk on Murashige and Skoog (MS) medium under normal conditions (normal) or subjected to 150 mM NaCl or 20% polyethylene glycol 6000 (PEG6000). (b) Responses of IbPRX17-OE and WT sweet potato plants grown hydroponically in half-strength Hoagland solution alone (normal) or with the addition of 200 mM NaCl or 20% PEG6000. Data are shown as means ± SD (n = 3). *, P < 0.05; **, P < 0.01 (significant difference from the WT at based on Student’s t-tests) (Adopted from Zhang et al., 2021)

4.2 Genetic basis of resistance to pests and diseases

The genetic transformation of sweet potato has led to the development of varieties with enhanced resistance to pests and diseases. For instance, transgenic sweet potatoes expressing the endotoxin genes cry8Db, cry7A1, and cry3Ca have shown lower infestation rates by the sweet potato weevil compared to non-transformed lines. Additionally, the expression of the oryzacystatin-1 (OC1) gene has conferred resistance to sweet potato stem nematodes and the sweet potato feathery mottle virus (SPFMV) (Imbo et al., 2016). The IbMIPS1 gene not only enhances abiotic stress tolerance but also significantly improves resistance to stem nematodes by modulating inositol and ABA signaling pathways (Zhai et al., 2016).

4.3 Pathways influencing growth, yield, and quality traits

Several pathways have been identified that influence the growth, yield, and quality traits of sweet potato. The overexpression of the IbC3H18 gene, a non-tandem CCCH-type zinc-finger protein, enhances tolerance to salt, drought, and oxidative stresses by regulating genes involved in ROS scavenging, ABA signaling, photosynthesis, and ion transport pathways (Zhang et al., 2019). The WRKY transcription factor ItfWRKY70 also contributes to improved growth and yield under drought conditions by increasing ABA and proline content, and enhancing the activity of superoxide dismutase (SOD) and peroxidase (POD) enzymes (Sun et al., 2022). Furthermore, the overexpression of the BADH gene from spinach in sweet potato leads to increased GB accumulation, which helps maintain cell membrane integrity, stronger photosynthetic activity, and reduced ROS production under stress conditions, thereby stabilizing yield production (Fan et al., 2012).

5 Molecular Mechanisms of Stress Response

5.1 Mechanisms at the cellular and molecular levels

Sweet potato, like many other plants, employs a variety of cellular and molecular mechanisms to respond to stress conditions. These mechanisms include the activation of specific genes and proteins that help the plant to cope with adverse environmental factors. For instance, the expression of certain transcription factors (TFs) such as NAC, WRKY, and MYB plays a crucial role in the plant's response to abiotic stresses like drought and salinity. These TFs regulate the expression of downstream genes involved in stress tolerance, including those that manage ion accumulation, redox reactions, and hormone signaling pathways (Meng et al., 2020; 2022; Sun et al., 2022; Zhao et al., 2022). Additionally, the plant’s response to potassium deficiency involves significant transcriptional changes. Genes related to transcriptional regulation, calcium binding, and redox signaling are differentially expressed under low potassium conditions, indicating their roles in stress adaptation (Wang et al., 2021). Moreover, miRNAs have been identified as key regulators in the salt stress response, modulating the expression of target genes involved in stress tolerance (Yang et al., 2020).

5.2 Regulatory networks involved in stress adaptation

The regulatory networks that govern stress adaptation in sweet potato are complex and involve multiple layers of control, including transcriptional, post-transcriptional, and post-translational modifications. Transcription factors such as IbNAC3 and IbMYB48 have been shown to interact with other proteins and regulatory elements to modulate stress responses. For example, IbNAC3 interacts with other NAC TFs to regulate the expression of genes involved in combined salt and drought stress tolerance (Meng et al., 2022). Similarly, IbMYB48 enhances salt and drought tolerance by upregulating genes involved in ABA biosynthesis, JA signaling, and ROS scavenging (Zhao et al., 2022). Furthermore, the integration of various signaling pathways, including those mediated by plant hormones like ABA, ethylene, and jasmonic acid, plays a pivotal role in coordinating the plant’s response to stress. These hormones regulate the expression of stress-responsive genes and proteins, thereby enhancing the plant’s ability to withstand adverse conditions (Golldack et al., 2011; Haak et al., 2017; Wang et al., 2021).

5.3 Role of transcription factors and other regulatory elements

Transcription factors are central to the regulation of stress responses in sweet potato. They act as master regulators that control the expression of a wide array of genes involved in stress tolerance. For instance, the NAC transcription factor IbNAC3 has been identified as a key player in modulating the plant's response to combined salt and drought stresses. It activates the expression of downstream target genes and interacts with other NAC TFs to enhance stress tolerance (Figure 2) (Meng et al., 2022). Similarly, the WRKY transcription factor ItfWRKY70 has been shown to confer drought tolerance by regulating ABA biosynthesis, stomatal aperture, and the ROS scavenging system (Sun et al., 2022). In addition to TFs, other regulatory elements such as miRNAs also play significant roles in stress adaptation. miRNAs regulate gene expression at the post-transcriptional level by targeting mRNAs for degradation or translational repression. For example, miRNAs have been shown to modulate the expression of genes involved in salt stress response, thereby contributing to the plant’s overall stress tolerance (Yang et al., 2020).

Figure 2 IbNAC3 cooperates with ANAC072 and NAP with a synergistic effect on transcriptional activation (Adopted from Meng et al., 2022) Image caption: (A) Heatmap showing hierarchical clustering of ChIP-seq peaks comparing transgenic and WT plants, indicating upregulated (red) and downregulated (blue) regions bound by IbNAC3. Plants were immunoprecipitated with an anti-Flag antibody, and the DNA-protein complexes were analyzed. (B) Schematics of AtCHX25, AtRH33, and MREL57 gene structures, highlighting core NACRS regions (red and blue) and exons (green), with distances from the ATG start codon marked. (C) ChIP-qPCR assays showing in vivo binding of IbNAC3 to the promoters of target genes, with significant enrichment compared to the WT. (D) Yeast one-hybrid assays confirming the physical interaction between IbNAC3 and the promoters of AtCHX25, AtRH33, and MREL57, validated on selective media. (E) Electrophoretic mobility shift assay (EMSA) illustrating in vitro binding of purified IbNAC3 to the promoters, showing specific DNA-protein complexes. (F) Diagrams of dual-luciferase reporter (DLR) constructs, showing promoters cloned into the reporter vector and effector constructs of IbNAC3, ANAC072, and NAP. (G) Transactivation assay results demonstrating that IbNAC3 activates transcription of the target promoters in Nicotiana benthamiana, as indicated by increased LUC/REN ratios. (H) Synergistic interaction between IbNAC3 and ANAC072/NAP further enhances the transactivation activity of the target gene promoters, with statistical analyses supporting significant interactions (Adapted from Meng et al., 2022)

6 Case Studies

6.1 Examples of specific sweet potato cultivars adapted to harsh environments

Several studies have identified sweet potato cultivars that exhibit remarkable adaptability to harsh environmental conditions. For instance, in Tanzania, the genotypes G2 (Resisto × Ukerewe), G3 (Ukerewe × Ex-Msimbu-1), G4 (03-03 x SPKBH008), G12 (Ukerewe × SPKBH008), and G18 (Resisto × Simama) have shown high yields, high dry matter content, and resistance to sweet potato virus disease (SPVD) across diverse environments (Ngailo et al., 2019). Similarly, in Indonesia, the genotypes Ayamurasaki, Beniazuma, Awachy2, 15(112), Awachy4, Awachy5, 80(109), 54(160), and 35(180) have been identified as specifically adapted to marginal lands based on Finlay-Wilkinson analysis (Mustamu et al., 2018).

In Colombia, the genotype 0113-672COR was selected for the Caribbean region due to its superior multi-trait performance and stability across multiple environments (Rosero et al., 2023). Additionally, a study in Cameroon identified high-yielding and stable sweet potato clones suitable for major cultivation areas, despite the significant genotype-by-environment interactions observed (Ngeve, 2004). These examples highlight the potential of specific sweet potato cultivars to thrive in challenging environments, contributing to food security and agricultural sustainability.

6.2 Insights from recent studies on gene-environment interactions

Recent studies have provided valuable insights into the gene-environment interactions that influence sweet potato adaptation. For instance, a transcriptomic analysis of the US-bred cultivar Beauregard and the Ugandan landrace Tanzania under dehydration stress identified approximately 4 000 to 6 000 differentially expressed genes in each cultivar, with many genes associated with drought response (Lau et al., 2018). This study highlighted the genotype-specific responses to drought stress, which can inform the development of drought-tolerant cultivars.

Another study emphasized the importance of understanding the genetic mechanisms underlying drought tolerance. It reviewed the physiological, metabolic, and genetic modifications that sweet potato plants employ to respond to water stress, such as activating antioxidants and accumulating stress proteins (Sapakhova et al., 2023). These modifications can serve as indicators for selecting drought-tolerant genotypes.

Furthermore, a study on the ecophysiological and morpho-agronomic parameters of sweet potato genotypes from different altitudes revealed significant variability in their responses to low-altitude conditions. Genotypes with greater soil coverage efficiency and leaf size exhibited better photosynthetic performance and water use efficiency, which are crucial for root formation under low-altitude environments (Figure 3) (Burbano-Erazo et al., 2020). These findings underscore the complex interactions between genetic traits and environmental factors in sweet potato adaptation.

Figure 3 Relationship between genotypes with storage roots and without storage roots according to Pn and altitude. Pn: Net photosynthetic rate; masl: meters above sea level (Adopted from Burbano-Erazo et al., 2020)

7 Future Directions and Challenges

7.1 Potential of CRISPR and other gene-editing tools in sweet potato breeding

The advent of CRISPR/Cas9 and other gene-editing technologies has revolutionized plant breeding, offering precise and efficient methods to modify genetic material. In sweet potato breeding, CRISPR/Cas9 has shown promise in improving starch quality by targeting specific genes involved in starch biosynthesis, such as IbGBSSI and IbSBEII (Wang et al., 2019). This technology allows for the introduction of desirable traits without the integration of foreign DNA, which is crucial for regulatory approval and public acceptance (Hameed et al., 2019; Veillet et al., 2019). Additionally, CRISPR/Cas9 can be used to enhance resistance to biotic and abiotic stresses, thereby improving crop resilience and yield (Biswas et al., 2021; Nascimento et al., 2023). The potential of CRISPR and other gene-editing tools in sweet potato breeding is vast, offering opportunities to accelerate the development of improved cultivars with enhanced nutritional quality and stress tolerance.

7.2 Challenges in translating genetic insights into practical breeding solutions

Despite the potential of gene-editing technologies, several challenges remain in translating genetic insights into practical breeding solutions. One major challenge is the genotype-dependency of transformation protocols, which affects the efficiency and success rate of gene editing in different sweet potato varieties (Nahirñak et al., 2022). Additionally, the regulatory landscape for gene-edited crops is complex and varies across regions, posing hurdles for the commercialization of gene-edited sweet potatoes (Hameed et al., 2019; Dev et al., 2021). Another challenge is the need for robust and efficient delivery systems for CRISPR/Cas9 components, as well as the development of marker-free strategies to avoid the integration of foreign DNA (Veillet et al., 2019; Tussipkan and Manabayeva, 2021). Furthermore, public perception and acceptance of gene-edited crops remain critical issues that need to be addressed through transparent communication and education (Chen et al., 2019).

7.3 Opportunities for integrating genomic data with traditional breeding methods

Integrating genomic data with traditional breeding methods presents a significant opportunity to enhance sweet potato breeding programs. By combining genomic selection with conventional breeding techniques, breeders can more accurately predict and select for desirable traits, thereby accelerating the breeding process (Dangol et al., 2019; Nascimento et al., 2023). The use of high-throughput sequencing and genotyping technologies enables the identification of genetic markers associated with important traits, facilitating marker-assisted selection (Chen et al., 2019; Biswas et al., 2021). Additionally, integrating genomic data with phenotypic data can improve the understanding of complex trait architectures and gene-environment interactions, leading to more targeted and efficient breeding strategies (Wang et al., 2019; Tussipkan and Manabayeva, 2021). This integrative approach holds the potential to develop sweet potato cultivars with improved yield, quality, and stress resilience, ultimately contributing to food security and sustainable agriculture.

8 Conclusion

Recent studies have significantly advanced our understanding of the genetic basis of sweet potato adaptation. High-throughput sequencing technologies have provided comprehensive genomic resources, revealing gene expression patterns across different tissues and developmental stages. Genome-wide analyses have identified numerous single nucleotide polymorphisms (SNPs) and expression quantitative trait loci (eQTLs) that regulate gene expression in sweet potato storage roots, highlighting key regulatory genes such as IbMYB1-2 involved in anthocyanin biosynthesis. Additionally, the identification and characterization of SWEET family genes and R2R3-MYB gene family members have elucidated their roles in sugar transport, stress responses, and anthocyanin accumulation. Studies on the wild ancestor, Ipomoea trifida, have further contributed to understanding the genetic diversity and evolutionary history of sweet potato.

The insights gained from these genetic studies have significant implications for sustainable sweet potato production. Understanding the molecular mechanisms underlying stress tolerance and nutrient accumulation can inform breeding programs aimed at developing more resilient and nutritious sweet potato varieties. The identification of key regulatory genes and pathways involved in biotic and abiotic stress responses can lead to the development of sweet potato cultivars with enhanced resistance to pests, diseases, and environmental stresses. Moreover, the comprehensive genomic resources and gene expression data provide valuable tools for marker-assisted selection and genetic engineering, facilitating the improvement of sweet potato yield and quality.

Future research should focus on further elucidating the functional roles of identified genes and their interactions in sweet potato adaptation. Functional validation of candidate genes through gene editing and transgenic approaches will be crucial to confirm their roles in stress tolerance and nutrient accumulation. Additionally, expanding genomic studies to include more diverse sweet potato cultivars and wild relatives will enhance our understanding of genetic diversity and adaptation mechanisms. Integrating multi-omics approaches, such as proteomics and metabolomics, with genomic data will provide a more comprehensive understanding of the molecular networks governing sweet potato adaptation. Finally, translating these genetic insights into practical breeding strategies will be essential for developing sustainable sweet potato varieties that can thrive in diverse environmental conditions.

Acknowledgments

The authors sincerely thank Professor Cai Renxiang from the Institute of Life Sciences at Jiyang College, Zhejiang A&F University, for carefully reviewing the manuscript and providing valuable suggestions for revisions. The authors also extend gratitude to the two anonymous peer reviewers for their insightful comments and recommendations.

Funding

This research was supported by the Grain and Oil Industry Technology Project of Zhejiang Province (Regional Trial Station) for 2021-2023 and the Hangzhou Agricultural Technology Chief Expert Workstation Project (Mini Sweet Potato Quality Improvement and Efficiency Enhancement Technology Innovation and Integration).

Conflict of Interest Disclosure

The author affirms that this research was conducted without any commercial or financial relationships that could be construed as a potential conflict of interest.

References

Alam M., 2021. A comprehensive review of sweet potato (Ipomoea batatas [L.] Lam): revisiting the associated health benefits, Trends in Food Science and Technology, 115: 512-529.

https://doi.org/10.1016/J.TIFS.2021.07.001

Arisha M., Ahmad M., Tang W., Liu Y., Yan H., Kou M., Wang X., Zhang Y., and Li Q., 2020, RNA-sequencing analysis revealed genes associated drought stress responses of different durations in hexaploid sweet potato, Scientific Reports, 10: 12573.

https://doi.org/10.1038/s41598-020-69232-3

PMid:32724138 PMCid:PMC7387466

Biswas S., Zhang D., and Shi J., 2021, CRISPR/Cas systems: opportunities and challenges for crop breeding, Plant Cell Reports, 40: 979-998.

https://doi.org/10.1007/s00299-021-02708-2

PMid:33977326

Burbano-Erazo E., Cordero C., Pastrana I., Espitia L., Gómez E., Morales A., Pérez J., López L., and Rosero A., 2020, Interrelation of ecophysiological and morpho-agronomic parameters in low altitude evaluation of selected ecotypes of sweet potato (Ipomoea batatas [L.] Lam.), Horticulturae, 6: 99.

https://doi.org/10.3390/horticulturae6040099

Chen K., Wang Y., Zhang R., Zhang H., and Gao C., 2019, CRISPR/Cas genome editing and precision plant breeding in agriculture, Annual Review of Plant Biology, 70: 667-697.

https://doi.org/10.1146/annurev-arplant-050718-100049

PMid:30835493

Dangol S., Barakate A., Stephens J., Çalışkan M., and Bakhsh A., 2019, Genome editing of potato using CRISPR technologies: current development and future prospective, Plant Cell, Tissue and Organ Culture (PCTOC), 139: 403-416.

https://doi.org/10.1007/s11240-019-01662-y

Dev S., Joseph J., and D’Rosario L., 2021, Prospects for genome editing of potato, In: Yildiz M., and Ozgen Y. (eds.), Solanum tuberosum - a promising crop for starvation problem, IntechOpen, London, UK, pp.354.

https://doi.org/10.5772/intechopen.99278

Ding N., Cui H., Miao Y., Tang J., Cao Q., and Luo Y., 2019, Single-molecule real-time sequencing identifies massive full-length cDNAs and alternative-splicing events that facilitate comparative and functional genomics study in the hexaploid crop sweet potato, PeerJ, 7: e7933.

https://doi.org/10.7717/peerj.7933

Escobar-Puentes A., Palomo I., Rodríguez L., Fuentes E., Villegas-Ochoa M., González-Aguilar G., Olivas-Aguirre F., and Wall-Medrano A., 2022, Sweet potato (Ipomoea batatas L.) phenotypes: from agroindustry to health effects, Foods, 11(7): 1058.

https://doi.org/10.3390/foods11071058

PMid:35407143 PMCid:PMC8997864

Fan W., Zhang M., Zhang H., and Zhang P., 2012, Improved tolerance to various abiotic stresses in transgenic sweet potato (Ipomoea batatas) expressing spinach betaine aldehyde dehydrogenase, PLoS One, 7(5): e37344.

https://doi.org/10.1371/journal.pone.0037344

PMid:22615986 PMCid:PMC3353933

Glato K., Aidam A., Kane N., Bassirou D., Couderc M., Zekraoui L., Scarcelli N., Barnaud A., and Vigouroux Y., 2017, Structure of sweet potato (Ipomoea batatas) diversity in West Africa covaries with a climatic gradient, PLoS One, 12(5): e0177697.

https://doi.org/10.1371/journal.pone.0177697

PMid:28552989 PMCid:PMC5446114

Golldack D., Lüking I., and Yang O., 2011, Plant tolerance to drought and salinity: stress regulating transcription factors and their functional significance in the cellular transcriptional network, Plant Cell Reports, 30: 1383-1391.

https://doi.org/10.1007/s00299-011-1068-0

PMid:21476089

Haak D., Fukao T., Grene R., Hua Z., Ivanov R., Perrella G., and Li S., 2017, Multilevel regulation of abiotic stress responses in plants, Frontiers in Plant Science, 8: 1564.

https://doi.org/10.3389/fpls.2017.01564

PMid:29033955 PMCid:PMC5627039

Hameed A., Mehmood M., Shahid M., Fatma S., Khan A., and Ali S., 2019, Prospects for potato genome editing to engineer resistance against viruses and cold-induced sweetening, GM Crops and Food, 11(4): 185-205.

https://doi.org/10.1080/21645698.2019.1631115

PMid:31280681 PMCid:PMC7518746

Hancock J., 2005, Contributions of domesticated plant studies to our understanding of plant evolution, Annals of Botany, 96(6): 953-963.

https://doi.org/10.1093/AOB/MCI259

PMid:16159942 PMCid:PMC4247096

Imbo M., Budambula N., Mweu C., Muli J., and Anami S., 2016, Genetic transformation of sweet potato for improved tolerance to stress: a review, Advances in Life Science and Technology, 49: 67-76.

Kyndt T., Quispe D., Zhai H., Jarret R., Ghislain M., Liu Q., Gheysen G., and Kreuze J., 2015, The genome of cultivated sweet potato contains Agrobacterium T-DNAs with expressed genes: an example of a naturally transgenic food crop, Proceedings of the National Academy of Sciences, 112: 5844-5849.

https://doi.org/10.1073/pnas.1419685112

PMid:25902487 PMCid:PMC4426443

Lamaro G., Tsehaye Y., and Girma A., 2022, Orange-fleshed sweet potato [Ipomoea batatas (L.) Lam] genotype by environment interaction for yield and yield components and SPVD resistance under arid and semi-arid climate of northern Ethiopia, Ethiopian Journal of Science and Technology, 15(3): 255-276.

https://doi.org/10.4314/ejst.v15i3.3

Lau K., Herrera M., Crisovan E., Wu S., Fei Z., Khan M., Buell C., and Gemenet D., 2018, Transcriptomic analysis of sweet potato under dehydration stress identifies candidate genes for drought tolerance, Plant Direct, 2(10): e00092.

https://doi.org/10.1002/PLD3.92

PMid:31245692 PMCid:PMC6508841

Meng X., Liu S., Dong T., Xu T., Ma D., Pan S., Li Z., and Zhu M., 2020, Comparative transcriptome and proteome analysis of salt-tolerant and salt-sensitive sweet potato and overexpression of IbNAC7 confers salt tolerance in Arabidopsis, Frontiers in Plant Science, 11: 572540.

https://doi.org/10.3389/fpls.2020.572540

PMid:32973858 PMCid:PMC7481572

Meng X., Liu S., Zhang C., He J., Ma D., Wang X., Dong T., Guo F., Cai J., Long T., Li Z., and Zhu M., 2022, The unique sweet potato NAC transcription factor IbNAC3 modulates combined salt and drought stresses, Plant Physiology, 191(1): 747-771.

https://doi.org/10.1093/plphys/kiac508

PMid:36315103 PMCid:PMC9806649

Motsa N., Modi A., and Mabhaudhi T., 2015, Sweet potato (Ipomoea batatas L.) as a drought tolerant and food security crop, South African Journal of Science, 111: 8.

https://doi.org/10.17159/SAJS.2015/20140252

Mustamu Y., Tjintokohadi K., Grüneberg W., Karuniawan A., and Ruswandi D., 2018, Selection of superior genotype of sweet-potato in Indonesia based on stability and adaptability, Chilean Journal of Agricultural Research, 78(4): 461-469.

https://doi.org/10.4067/S0718-58392018000400461

Nahirñak V., Almasia N., González M., Massa G., Oneto C., Feingold S., Hopp H., and Rovere C., 2022, State of the art of genetic engineering in potato: from the first report to its future potential, Frontiers in Plant Science, 12: 768233.

https://doi.org/10.3389/fpls.2021.768233

PMid:35082806 PMCid:PMC8784693

Nascimento F., Rocha A., Soares J., Mascarenhas M., Ferreira M., Lino L., Ramos A., Diniz L., Mendes T., Ferreira C., Santos-Serejo J., and Amorim E., 2023, Gene editing for plant resistance to abiotic factors: a systematic review, Plants, 12(2): 305.

https://doi.org/10.3390/plants12020305

PMid:36679018 PMCid:PMC9860801

Ngailo S., Shimelis H., Sibiya J., Mtunda K., and Mashilo J., 2019, Genotype-by-environment interaction of newly-developed sweet potato genotypes for storage root yield, yield-related traits and resistance to sweet potato virus disease, Heliyon, 5(3): e01448.

https://doi.org/10.1016/j.heliyon.2019.e01448

PMid:30976707 PMCid:PMC6441836

Ngeve J., 2004, Regression analysis of genotype x environment interaction in sweet potato, Euphytica, 71: 231-238.

https://doi.org/10.1007/BF00040412

Pironon S., and Gomez M., 2020, Plant agrodiversity to the rescue, Nature Climate Change, 11: 6-8.

https://doi.org/10.1038/s41558-020-00925-3

Rodríguez-Bonilla L., Cuevas H., Montero-Rojas M., Bird-Picó F., Luciano-Rosario D., and Siritunga D., 2014, Assessment of genetic diversity of sweet potato in Puerto Rico, PLoS One, 9(12): e116184.

https://doi.org/10.1371/journal.pone.0116184

PMid:25551388 PMCid:PMC4281141

Rosero A., Burgos-Paz W., Araujo H., Pastrana-Vargas I., Martínez R., Pérez J., and Espitia L., 2023, Sweet potato varietal selection using combined methods of multi-trait index, genetic gain and stability from multi-environmental evaluations, Horticulturae, 9(9): 974.

https://doi.org/10.3390/horticulturae9090974

Sapakhova Z., Raissova N., Daurov D., Zhapar K., Daurova A., Zhigailov A., Zhambakin K., and Shamekova M., 2023, Sweet potato as a key crop for food security under the conditions of global climate change: a review, Plants, 12(13): 2516.

https://doi.org/10.3390/plants12132516

PMid:37447081 PMCid:PMC10346279

Solankey S., Singh P., and Singh R., 2015, Genetic diversity and interrelationship of qualitative and quantitative traits in sweet potato, International Journal of Vegetable Science, 21: 236-248.

https://doi.org/10.1080/19315260.2013.867295

Sun H., Mu T., Xi L., Zhang M., and Chen J., 2014, Sweet potato (Ipomoea batatas L.) leaves as nutritional and functional foods, Food Chemistry, 156: 380-389.

https://doi.org/10.1016/j.foodchem.2014.01.079

PMid:24629984

Sun S., Li X., Gao S., Nie N., Zhang H., Yang Y., He S., Liu Q., and Zhai H., 2022, A novel WRKY transcription factor from Ipomoea trifida, ItfWRKY70, confers drought tolerance in sweet potato, International Journal of Molecular Sciences, 23(2): 686.

https://doi.org/10.3390/ijms23020686

PMid:35054868 PMCid:PMC8775875

Tao X., Gu Y., Wang H., Zheng W., Li X., Zhao C., and Zhang Y., 2012, Digital gene expression analysis based on integrated de novo transcriptome assembly of sweet potato [Ipomoea batatas (L.) Lam.], PLoS One, 7(4): e36234.

https://doi.org/10.1371/journal.pone.0036234

PMid:22558397 PMCid:PMC3338685

Tussipkan D., and Manabayeva S., 2021, Employing CRISPR/Cas technology for the improvement of potato and other tuber crops, Frontiers in Plant Science, 12: 747476.

https://doi.org/10.3389/fpls.2021.747476

PMid:34764969 PMCid:PMC8576567

Veillet F., Perrot L., Chauvin L., Kermarrec M., Guyon-Debast A., Chauvin J., Nogué F., and Mazier M., 2019, Transgene-free genome editing in tomato and potato plants using agrobacterium-mediated delivery of a CRISPR/Cas9 cytidine base editor, International Journal of Molecular Sciences, 20(2): 402.

https://doi.org/10.3390/ijms20020402

PMid:30669298 PMCid:PMC6358797

Wang F., Tan W., Song W., Yang S., and Qiao S., 2021, Transcriptome analysis of sweet potato responses to potassium deficiency, BMC Genomics, 23: 655.

https://doi.org/10.1186/s12864-022-08870-5

PMid:36109727 PMCid:PMC9479357

Wang H., Wu Y., Zhang Y., Yang J., Fan W., Zhang H., Zhao S., Yuan L., and Zhang P., 2019, CRISPR/Cas9-based mutagenesis of starch biosynthetic genes in sweet potato (Ipomoea batatas) for the improvement of starch quality, International Journal of Molecular Sciences, 20(19): 4702.

https://doi.org/10.3390/ijms20194702

PMid:31547486 PMCid:PMC6801948

Yang Z., Zhu P., Kang H., Liu L., Cao Q., Sun J., Dong T., Zhu M., Li Z., and Xu T., 2020, High-throughput deep sequencing reveals the important role that microRNAs play in the salt response in sweet potato (Ipomoea batatas L.), BMC Genomics, 21: 164.

https://doi.org/10.1186/s12864-020-6567-3

PMid:32066373 PMCid:PMC7027035

Zhai H., Wang F., Si Z., Huo J., Xing L., An Y., He S., and Liu Q., 2016, A myo-inositol-1-phosphate synthase gene, IbMIPS1, enhances salt and drought tolerance and stem nematode resistance in transgenic sweet potato, Plant Biotechnology Journal, 14(2): 592-602.

https://doi.org/10.1111/pbi.12402

PMid:26011089

Zhang H., Gao X., Zhi Y., Li X., Zhang Q., Niu J., Wang J., Zhai H., Zhao N., Li J., Liu Q., and He S., 2019, A non-tandem CCCH-type zinc-finger protein, IbC3H18, functions as a nuclear transcriptional activator and enhances abiotic stress tolerance in sweet potato, The New Phytologist, 223(4): 1918-1936.

https://doi.org/10.1111/nph.15925

PMid:31091337

Zhang H., Wang Z., Li X., Gao X., Dai Z., Cui Y., Zhi Y., Liu Q., Zhai H., Gao S., Zhao N., and He S., 2021, The IbBBX24-IbTOE3-IbPRX17 module enhances abiotic stress tolerance by scavenging reactive oxygen species in sweet potato, The New Phytologist, 233(3): 1133-1152.

https://doi.org/10.1111/nph.17860

PMid:34773641

Zhang L., Yu Y., Shi T., Kou M., Sun J., Xu T., Li Q., Wu S., Cao Q., Hou W., and Li Z., 2020, Genome-wide analysis of expression quantitative trait loci (eQTLs) reveals the regulatory architecture of gene expression variation in the storage roots of sweet potato, Horticulture Research, 7: 90.

https://doi.org/10.1038/s41438-020-0314-4

PMid:32528702 PMCid:PMC7261777

Zhao H., Zhao H., Hu Y., Zhang S., He S., Zhang H., Zhao N., Liu Q., Gao S., and Zhai H., 2022, Expression of the sweet potato MYB transcription factor IbMYB48 confers salt and drought tolerance in Arabidopsis, Genes, 13(10): 1883.

https://doi.org/10.3390/genes13101883

PMid:36292768 PMCid:PMC9602379