Phytochrome-interacting factors (PIFs) were initially recognized as pivotal regulators of plant light signaling pathways. However, mounting evidence suggests that PIFs also exert significant influences on plant development and responses to stress. Here, we identified seven PIF genes in the potato genome and conducted comprehensive characterizations through phylogenetics, gene structure, conserved motif, synteny, chromosomal location analyses and cis-regulatory element. Transcriptome data and gene expression analysis showed that the StPIF4 gene was markedly induced by mannitol-induced water deficit. Additionally, the StPIF4 protein was primarily localized in the nucleus and plasma membrane. In order to explore the function of the StPIF4 gene under mannitol-induced water deficit, the StPIF4 gene was cloned, and several StPIF4 overexpression (OE) lines (OE-8, OE-10, and OE-11) and three RNA interference (RNAi) transgenic lines (RNAi-5, RNAi-9, and RNAi-11) were obtained. The OE lines displayed notable enhancements in various growth parameters such as plant height, leaf number, branch number, fresh weight, dry weight, total root length, root surface area, number of root forks, and number of root tips under mannitol-induced water deficit compared to the wild-type (WT) lines, whereas these parameters were significantly decreased in the RNAi lines. The activities of antioxidant enzymes (SOD, POD, CAT) and the accumulation of proline and soluble sugars were also significantly increased under mannitol-induced water deficit, whereas the levels of thiobarbituric acid reactive substances (TBARSs) and reactive oxygen species (ROS), including hydrogen peroxide (H2O2) and O2-, were significantly reduced in the OE lines compared to WT plants under mannitol-induced water deficit. Moreover, the stomatal aperture of the leaves and the water loss rate in the leaves of the OE lines were significantly reduced under mannitol-induced water deficit compared to the WT plants, whereas for the RNAi lines they were significantly increased. In addition, the overexpression of StPIF4 also upregulated expression of drought-responsive genes and ABA content under mannitol-induced water deficit. Collectively, these results highlight the positive role of the StPIF4 gene in enhancing potato tolerance to mannitol-induced water deficit by decreasing stomatal aperture, enhancing ROS scavenging and mitigating oxidative damage.

The hormone jasmonic acid (JA) regulates plant growth and development, acts as a stress-tolerant signaling molecule, and ensures tolerance to drought stressors. The jasmonate zim-domain (JAZ) functions as a transcriptional repressor by directly interacting with transcription factors, regulating the activity of JA pathway transcription factors when JA signaling is absent. We systematically identified JAZ gene family members using a maize pangenome comprising 26 high-quality genomes. We analyzed evolutionary pressure and structural variation (SV), and reanalyzed public RNA-seq data under drought stress. Sequential expression patterns were further validated using qRT-PCR. In this study, 112 JAZ genes were identified by pan-genomic analysis of 26 high-quality maize genomes, including 12 core genes (present in all 26 lines), 33 non-core genes (in 2–22 lines), 5 near-core genes (in 23–25 lines), and 62 endemic genes (in 1 line). Analysis of Ka/Ks values showed that some varieties were under positive selection for the JAZ19 gene. Among these, 15 ZmJAZ genes had Ka/Ks values < 1, indicating they were subject to purifying selection. There were significant differences in the expression of ZmJAZ19 between genes affected by structural variation (SV) and those not affected by SV. SV altered the conserved structural domains in some varieties, resulting in a significant number of atypical genes. RNA-seq analysis of drought treatment data revealed seven differentially expressed ZmJAZ genes, four of which were core genes. However, atypical genes were identified in numerous response genes across multiple genomes. This study advances our understanding of how ZmJAZ genes contribute to drought adaptation in maize, offering a conceptual framework that links molecular responses to climate-resilient traits essential for sustainable crop production under water-limited conditions in the face of climate change.

The JASMONATE-ZIM DOMAIN (JAZ) repressors are crucial proteins in the jasmonic acid signaling pathway that play a significant role in plant growth, development and response to abiotic stress (such as drought, heat, salinity, and low temperature). In this study, we identified 26 potato JAZ genes and classified the corresponding predicted proteins into five subfamilies. All potato JAZ proteins exhibited the expected conserved TIFY (TIF[F/Y] XG) and JAZ domains. Additionally, we identified several stress-responsive cis-regulatory elements, notably ABRE and ARE in the promoters of the JAZ gene family. Whole transcriptome and gene family expression analysis identified StJAZ23 as a key gene responding to drought stress in the root tissues of the Atlantic (Atl) and Qingshu 9 (QS9) potato cultivars. The StJAZ23 gene was cloned, and subcellular localization analysis suggested that the StJAZ23 protein was mainly localized in the nucleus and cell membrane. This study confirmed that StJAZ23 plays a role in drought stress by analyzing several StJAZ23 overexpression (OE-3, OE-5, and OE-6) and RNA interference (RNAi-3, RNAi-6, and RNAi-13) transgenic potato lines. The OE lines displayed significantly increased StJAZ23 expression compared to wild-type (WT) plants, while RNAi lines exhibited significantly reduced expression. The total root length, root tip count, and root surface area were significantly enhanced in OE lines under drought stress, compared to WT plants, whereas RNAi lines showed significant reductions. StJAZ23 overexpression also increased the activities of SOD, POD, CAT, and root vigor under drought stress and JA and ABA hormone levels were also significantly increased in roots under drought stress. These results highlight the positive role of the StJAZ23 gene in enhancing potato resilience to drought stress.

To improve the accuracy of the photo chlorophyll content estimation model, the remote sensing images of different growth stages of potatoes under control and drought treatments were obtained using a multi-spectral camera on a UAV platform. Thirteen vegetation indices were selected as input variables of the chlorophyll content inversion model, and the estimation model of potato chlorophyll content was constructed by using multiple linear regression (MLR), support vector regression (SVR), random forest regression (RFR) and decision tree regression (DTR). Correlation analysis between vegetation index and chlorophyll content showed that at the tuber formation stage of the control treatment, the absolute values of correlation coefficients between CIre, GNDVI, NDVIre, NDWI, GRVI, LCI and chlorophyll content were above 0.5, and their were significant (p<0.05) or highly significant (p<0.01) correlations. In other growth stages of potato, the absolute values of correlation coefficients between 13 vegetation indexes and chlorophyll content were all above 0.5, which was a highly significant correlation (p<0.001). In addition, the accuracy of MLR, SVR, RFR and DTR models were compared. The results showed that the SVR model has the best prediction effects in the tuber formation stage, tuber expansion stage and starch accumulation stage of the control treatment. The control treatment's R-2 and RMSE were 0.89 and 2.11 in the tuber formation stage, 0.59 and 4.03 in the tuber expansion stage, and 0.80 and 3.18 in the starch accumulation stage. The RFR model produces the best prediction effects in the tuber formation, tuber expansion, and starch accumulation stages of the drought treatment. The outcomes of R-2 and RMSE on drought treatment were 0.90 and 1.57 in the tuber formation stage, 0.87 and 2.16 in the tuber expansion stage, and 0.63 and 3.01 in the starch accumulation stage. This study presents a new approach for monitoring the chlorophyll content of potatoes, and a corresponding estimating model can be selected based on the specific potato growth stage and different experimental treatments in future.

The root system plays a decisive role in the growth and development of plants. The water requirement of a root system depends strongly on the plant species. Potatoes are an important food and vegetable crop grown worldwide, especially under irrigation in arid and semi-arid regions. However, the expected impact of global warming on potato yields calls for an investigation of genes related to root development and drought resistance signaling pathways in potatoes. In this study, we investigated the molecular mechanisms of different drought-tolerant potato root systems in response to drought stress under controlled water conditions, using potato as a model. We analyzed the transcriptome and proteome of the drought-sensitive potato cultivar Atlantic (Atl) and the drought-tolerant cultivar Qingshu 9 (Q9) under normal irrigation (CK) and weekly drought stress (D). The results showed that a total of 14,113 differentially expressed genes (DEGs) and 5596 differentially expressed proteins (DEPs) were identified in the cultivars. A heat map analysis of DEGs and DEPs showed that the same genes and proteins in Atl and Q9 exhibited different expression patterns under drought stress. Weighted gene correlation network analysis (WGCNA) showed that in Atl, Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG)-enriched pathways were related to pyruvate metabolism and glycolysis, as well as cellular signaling and ion transmembrane transporter protein activity. However, GO terms and KEGG-enriched pathways related to phytohormone signaling and the tricarboxylic acid cycle were predominantly enriched in Q9. The present study provides a unique genetic resource to effectively explore the functional genes and uncover the molecular regulatory mechanism of the potato root system in response to drought stress.

Drought stress is a major threat to sustainable crop production worldwide. Despite the positive role of calcium (Ca2+) in improving plant drought tolerance in different crops, little attention has been paid to its role in mitigating drought stress in potatoes. In the present study, we studied the effect of foliar chelated sugar alcohol calcium treatments on two potato cultivars with different drought responses applied 15 and 30 days after limiting soil moisture. The results showed that the foliar application of calcium treatments alleviated the SPAD chlorophyll loss of the drought-sensitive cultivar 'Atlantic' (Atl) and reduced the inhibition of photosynthetic parameters, leaf anatomy deformation, and MDA and H2O2 content of both cultivars under drought stress. The Ca2+ treatments changed the expression of several Calcium-Dependent Protein Kinase (StCDPK) genes involved in calcium sensing and signaling and significantly increased antioxidant enzyme activities, average tuber weight per plant, and tuber quality of both cultivars. We conclude that calcium spray treatments improved the drought tolerance of both potato cultivars and were especially effective for the drought-sensitive cultivar. The present work suggests that the foliar application of calcium is a promising strategy to improve commercial potato yields and the economic efficiency of potato production under drought stress conditions.

As an important hormone response gene, Gretchen Hagen 3 (GH3) maintains hormonal homeostasis by conjugating excess auxin with amino acids during plant stress-related signaling pathways. GH3 genes have been characterized in many plant species, but they are rarely reported in potato. Here, 19 StGH3 genes were isolated and characterized. Phylogenetic analysis indicated that StGH3s were divided into two categories (group I and group III). Analyses of gene structure and motif composition showed that the members of a specific StGH3 subfamily are relatively conserved. Collinearity analysis of StGH3 genes in potato and other plants laid a foundation for further exploring the evolutionary characteristics of the StGH3 genes. Promoter analysis showed that most StGH3 promoters contained hormone and abiotic stress response elements. Multiple transcriptome studies indicated that some StGH3 genes were responsive to ABA, water deficits, and salt treatments. Moreover, qRT-PCR analysis indicated that StGH3 genes could be induced by phytohormones (ABA, SA, and MeJA) and abiotic stresses (water deficit, high salt, and low temperature), although with different patterns. Furthermore, transgenic tobacco with transient overexpression of the StGH3.3 gene showed positive regulation in response to water deficits by increasing proline accumulation and reducing the leaf water loss rate. These results suggested that StGH3 genes may be involved in the response to abiotic stress through hormonal signal pathways. Overall, this study provides useful insights into the evolution and function of StGH3s and lays a foundation for further study on the molecular mechanisms of StGH3s in the regulation of potato drought resistance.

Abscisic acid (ABA) is an important stress hormone that affects plants' tolerance to stress. Changes in the content of abscisic can have an impact on plant responses to abiotic stress. The abscisic acid aldehyde oxidase (AAO) plays a crucial role in the final step in the synthesis of abscisic acid; therefore, understanding the function of the AAO gene family is of great significance for insight into plants' response to abiotic stresses. In this study, Solanum tuberosum AAO (StAAO) members were exhaustively explored using genome databases, and nine StAAOs were identified. Chromosomal location analysis indicated that StAAO genes mapped to 4 of the 14 potato chromosomes. Further analyses of gene structure and motif composition showed that members of the specific StAAO subfamily showed relatively conserved characteristics. Phylogenetic relationship analysis indicated that StAAOs proteins were divided into three major clades. Promoter analysis showed that most StAAO promoters contained cis-elements related to abiotic stress response and plant hormones. The results of tissue-specific expression analysis indicated that StAAO4 was predominantly expressed in the roots. Analysis of transcriptome data revealed that StAAO2/4/6 genes responded significantly to drought treatments. Moreover, further qRT-PCR analysis results indicated that StAAO2/4/6 not only significantly responded to drought stress but also to various phytohormone (ABA, SA, and MeJA) and abiotic stresses (salt and low temperature), albeit with different expression patterns. In summary, our study provides comprehensive insights into the sequence characteristics, structural properties, evolutionary relationships, and expression patterns of the StAAO gene family. These findings lay the foundation for a deeper understanding of the StAAO gene family and offer a potential genetic resource for breeding drought-resistant potato varieties.

Sucrose non-ferment 1-related protein kinase 2 (SnRK2) is a highly conserved protein kinase in plants that plays an important role in regulating plant response to drought stress. Although it has been reported in some plants, the evolutionary relationship of potato SnRK2s and their function in drought resistance have not been systematically analyzed. In this study, molecular characteristic analysis showed that 8 StSnRK2s were distributed on six chromosomes, coding proteins were divided into three subgroups, and StSnRK2s clustered in the same subgroup had similar conserved motifs and domains. In addition, StSnRK2 has a wide range of replication events in some species, making it closer to dicots in the process of evolution. In addition, the average nonsynonymous substitution rate/synonymous substitution rate (Ka/Ks) value of SnRK2s in monocots was higher than that of dicots. The codon usage index showed that SnRK2s prefer to use cytosine 3 (C3s), guanine 3 (G3s) and GC content (GC3s) in monocots, whereas thymine 3 (T3s) and adenine 3 (A3s) are preferred in dicots. Furthermore, stress response analysis showed that the expression of StSnRK2s under different degrees of drought stress significantly correlated with one or more stress-related physiological indices, such as proline and malondialdehyde (MDA) content, superoxide dismutase (SOD) and catalase (CAT) activity, ion leakage (IL) etc. The drought resistance of StSnRK2 transgenic plants was determined to occur in the order of StSnRK2.1/2.8 > StSnRK2.2/2.5 > StSnRK2.4/2.6 > StSnRK2.3 > StSnRK2.7, was attributed to not only lower IL but also higher proline, soluble sugar contents and stress-related genes in transgenic plants compared to wild type (WT). In conclusion, this study provides useful insights into the evolution and function of StSnRK2s and lays a foundation for further study on the molecular mechanism of StSnRK2s regulating potato drought resistance.

In order to investigate the relationship between hydraulic lift and drought tolerance in potato, four cultivars differing in drought susceptibilities were selected, and a pot experiment with three different irrigation conditions was carried out in a randomized complete block design. Under irrigation conditions (WW), hydraulic lift of soil water was not observed in the upper pots. Under half-irrigation (DW) and drought (DD) conditions, the water content increased in the upper pots, along with a change in root-related traits, higher biomass, and lower proline (Pro) and malondialdehyde (MDA) concentrations observed in the drought-tolerant cultivars (Longshu NO.3 and Xindaping), whereas the drought-sensitive cultivars (Favorita and Atlantic) had contrary results. As the degree of drought stress increased, the phenomenon of hydraulic lift was inhibited completely, along with a reduction in soil water content and biomass and an increase in Pro and MDA accumulation. Genotypes of Longshu NO.3 and Xindaping exhibited higher tolerance to drought stress than Favorita and Atlantic under drought conditions. In addition, similar results were also obtained for the determination of plant height, leaf water content, root activity, and root–shoot ratio. This study revealed that there was a phenomenon of hydraulic redistribution among different potato cultivars, along with hydraulic lift strongly associated with the root growth, biomass allocation, and other physiological traits that potentially confer drought resistance.

The study was conducted with C31 and C80 genotypes of the potato (Solanum tuberosum L.), which are tolerant and susceptible to phosphite (Phi, H2PO3), respectively. To decipher the molecular mechanisms underlying tolerance and susceptibility to Phi in the potato, RNA sequencing was used to study the global transcriptional patterns of the two genotypes. Media were prepared with 0.25 and 0.50 mM Phi, No-phosphorus (P), and 1.25 mM (phosphate, Pi as control). The values of fragments per kilobase of exon per million mapped fragments of the samples were also subjected to a principal component analysis, grouping the biological replicates of each sample. Using stringent criteria, a minimum of 819 differential (DEGs) were detected in both C80-Phi-0.25_vs_C80-Phi-0.50 (comprising 517 upregulated and 302 downregulated) and C80-Phi-0.50_vs_C80-Phi-0.25 (comprising 302 upregulated and 517 downregulated) and a maximum of 5214 DEGs in both C31-Con_vs_C31-Phi-0.25 (comprising 1947 upregulated and 3267 downregulated) and C31-Phi-0.25_vs_C31-Con (comprising 3267 upregulated and 1947 downregulated). DEGs related to the ribosome, plant hormone signal transduction, photosynthesis, and plant–pathogen interaction performed important functions under Phi stress, as shown by the Kyoto Encyclopedia of Genes and Genomes annotation. The expressions of transcription factors increased significantly in C31 compared with C80. For example, the expressions of Soltu.DM.01G047240, Soltu.DM.08G015900, Soltu.DM.06G012130, and Soltu.DM.08G012710 increased under P deficiency conditions (Phi-0.25, Phi-0.50, and No-P) relative to the control (P sufficiency) in C31. This study adds to the growing body of transcriptome data on Phi stress and provides important clues to the Phi tolerance response of the C31 genotype.

Potato is one of the most important vegetable crops worldwide. Its growth, development and ultimately yield is hindered by drought stress condition. Breeding and selection of deep-rooted and drought-tolerant potato varieties has become a prime approach for improving the yield and quality of potato (Solanum tuberosum L.) in arid and semiarid areas. A comprehensive understanding of root development-related genes has enabled scientists to formulate strategies to incorporate them into breeding to improve complex agronomic traits and provide opportunities for the development of stress tolerant germplasm. Root response to drought stress is an intricate process regulated through complex transcriptional regulatory network. To understand the rooting depth and molecular mechanism, regulating root response to drought stress in potato, transcriptome dynamics of roots at different stages of drought stress were analyzed in deep (C119) and shallow-rooted (C16) cultivars. Stage-specific expression was observed for a significant proportion of genes in each cultivar and it was inferred that as compared to C16 (shallow-rooted), approximately half of the genes were differentially expressed in deep-rooted cultivar (C119). In C16 and C119, 11 and 14 coexpressed gene modules, respectively, were significantly associated with physiological traits under drought stress. In a comparative analysis, some modules were different between the two cultivars and were associated with differential response to specific drought stress stage. Transcriptional regulatory networks were constructed, and key components determining rooting depth were identified. Through the results, we found that rooting depth (shallow vs deep) was largely determined by plant-type, cell wall organization or biogenesis, hemicellulose metabolic process, and polysaccharide metabolic process. In addition, candidate genes responding to drought stress were identified in deep (C119) and shallow (C16) rooted potato varieties. The results of this study will be a valuable source for further investigations on the role of candidate gene(s) that affect rooting depth and drought tolerance mechanisms in potato.

The selection and breeding of deep rooting and drought-tolerant varieties has become a promising approach for improving the yield and adaptability of potato (Solanum tuberosum L.) in arid and semiarid areas. Therefore, the discovery of root-development-related genes and drought tolerance signaling pathways in potato is important. In this study, we used deep-rooting (C119) and shallow-rooting (C16) potato genotypes, with different levels of drought tolerance, to achieve this objective. Both genotypes were treated with 150 mM mannitol for 0 h (T0), 2 h (T2), 6 h (T6), 12 h (T12), and 24 h (T24), and their root tissues were subjected to comparative transcriptome analysis. A total of 531, 1571, 1247, and 3540 differentially expressed genes (DEGs) in C16 and 1531, 1108, 674, and 4850 DEGs in C119 were identified in T2 vs. T0, T6 vs. T2, T12 vs. T6, and T24 vs. T12 comparisons, respectively. Gene expression analysis indicated that a delay in the onset of drought-induced transcriptional changes in C16 compared with C119. Functional enrichment analysis revealed genotype-specific biological processes involved in drought stress tolerance. The metabolic pathways of plant hormone transduction and MAPK signaling were heavily involved in the resistance of C16 and C119 to drought, while abscisic acid (ABA), ethylene, and salicylic acid signal transduction pathways likely played more important roles in C119 stress responses. Furthermore, genes involved in root cell elongation and division showed differential expression between the two genotypes under drought stress. Overall, this study provides important information for the marker-assisted selection and breeding of drought-tolerant potato genotypes.

Calcium-dependent protein kinases (CDPKs) are a class of serine/threonine protein kinases encoded by several gene families that play key roles in stress response and plant growth and development. In this study, the BLAST method was used to search for protein sequences of the potato Calcium-dependent protein kinase gene family. The chromosome location, phylogeny, gene structures, gene duplication, cis-acting elements, protein-protein interaction, and expression profiles were analyzed. Twenty-five CDPK genes in the potato genome were identified based on RNA-seq data and were clustered into four groups (I-IV) based on their structural features and phylogenetic analysis. The result showed the composition of the promoter region of the StCDPKs gene, including light-responsive elements such as Box4, hormone-responsive elements such as ABRE, and stress-responsive elements such as MBS. Four pairs of segmental duplications were found in StCDPKs genes and the Ka/Ks ratios were below 1, indicating a purifying selection of the genes. The protein-protein interaction network revealed defense-related proteins such as; respiratory burst oxidase homologs (RBOHs) interacting with potato CDPKs. Transcript abundance was measured via RT-PCR between the two cultivars and their relative expression of CDPK genes was analyzed after 15, 20, and 25 days of drought. There were varied expression patterns of StCDPK3/13/21 and 23, between the two potato cultivars under mannitol induced-drought conditions. Correlation analysis showed that StCDPK21/22 and StCDPK3 may be the major differentially expressed genes involved in the regulation of malondialdehyde (MDA) and proline content in response to drought stress, opening a new research direction for genetic improvement of drought resistance in potato.

Crop growth and development are frequently affected by biotic and abiotic stresses. The adaptation of crops to stress is mostly achieved by regulating specific genes. The root system is the primary organ for nutrient and water uptake, and has an important role in drought stress response. The improvement of stress tolerance to increase crop yield potential and yield stability is a traditional goal of breeders in cultivar development using integrated breeding methods. An improved understanding of genes that control root development will enable the formulation of strategies to incorporate stress-tolerant genes into breeding for complex agronomic traits and provide opportunities for developing stress-tolerant germplasm. We screened the genes associated with root growth and development from diverse plants including Arabidopsis, rice, maize, pepper and tomato. This paper provides a theoretical basis for the application of root-related genes in molecular breeding to achieve crop drought tolerance by the improvement of root architecture.

In order to identify the single nucleotide polymorphism (SNP) of StDRO1 gene associated with potato root traits, StDRO1 gene coding region of the 110 tetraploid potato genotypes was cloned and sequenced. The association analysis between the StDRO1 SNPs and the major root traits of potato such as surface area, volume, and average diameter were carried out. The results showed that a SNP (G64C) was detected in the second exon of the StDRO1, 10 SNPs (G152A, A214G, A297G, C314T, A337T, T353C, T560A, C577A, C620A, and C625A) were identified in the third exon, and a SNP (T793A) was detected in the fourth exon. The association analysis indicated that in the total root volume, G152A locus of StDRO1 gene showed that GA genotype was superior to GG genotype (P < 0.05). In the average root diameter, C314 locus showed that CC genotype were superior to CT genotype (P < 0.05). In the root surface area, fresh weight, and dry weight, A337T locus showed that AT genotype were better than AA genotype (P < 0.05), while the locus in the average root diameter showed that AT genotype was significantly lower than AA genotype (P < 0.05). The root surface area, root volume, and fresh weight were showed as TC genotype > TT genotype (P < 0.05) in T353C site; the root volume was showed as CA genotype > CC genotype (P < 0.05) in C620A site; the root surface area, root volume, and fresh weight were showed as AT genotype > TT genotype (P < 0.05) in T793A site. In summary, the above six SNPs of StDRO1 genes had a significant impact on potato root traits, and the A337T, T353C, and T793A sites were particularly important. These results provide a basic theoretical reference for subsequent potato root architecture research and genetic improvement, but whether it could be used as a genetic marker for potato root traits need to be further verified by expanding the population sample.

Potato (Solanum tuberosum L) is the third important crop for providing calories to a large human population, and is considered sensitive to moderately sensitive to drought stress conditions. The development of drought-tolerant, elite varieties of potato is a challenging task, which can be achieved through molecular breeding. Recently, the DEEPER ROOTING 1 (DRO1) gene has been identified in rice, which influences plant root system and regulates grain yield under drought stress conditions. The potato StDRO1 protein is mainly localized in the plasma membrane of tobacco leaf cells, and overexpression analysis of StDRO1 in Arabidopsis resulted in an increased lateral root number, but decreased lateral root angle, lateral branch angle, and silique angle. Additionally, the drought treatment analysis indicated that StDRO1 regulated drought tolerance and rescued the defective root architecture and drought-tolerant phenotypes of Atdro1, an Arabidopsis AtDRO1 null mutant. Furthermore, StDRO1 expression was significantly higher in the drought-tolerant potato cultivar "Unica" compared to the drought-sensitive cultivar "Atlantic." The transcriptional response of StDRO1 under drought stress occurred significantly earlier in Unica than in Atlantic. Collectively, the outcome of the present investigation elucidated the role of DRO1 function in the alternation of root architecture, which potentially acts as a key gene in the development of a drought stress-tolerant cultivar. Furthermore, these findings will provide the theoretical basis for molecular breeding of drought-tolerant potato cultivars for the farming community.

When plants are subjected to water stress, they will make a rapid response to drought stress through DNA methylation. In order to study how DNA methylation affects the transcriptional expression of genes under drought stress in potato, comparative transcriptomic analysis was carried out on two potato varieties with different drought resistances, which were planted under mannitol simulated drought and 5-azadC treatments. The differentially expressed genes (DEGs) were identified by Fold-change > 2 and corrected P < 0.01. Then DEGs were subjected to GO enrichment analysis. The results showed that these DEGs were enriched in the oxidative stress and carbohydrate metabolism, suggesting these GO term-related genes were also regulated by DNA demethylation, responded to drought stress in different drought-tolerant potatoes. The common 1345 DEGs both responding to drought stress and DNA demethylation were functionally enriched by KEGG pathway. The results showed that plant MAPK signal pathway, plant hormone signal transduction pathway, plant glutathione metabolism pathway, glycolysis and glutathione metabolism pathway and inositol phosphate metabolism pathway were related to plant drought resistance. It was suggested that the sensitivity of these pathway-related genes responding to drought stress were regulated by DNA methylation in Atlantic and Qingshu 9. The cis-acting elements and methylated CpG islands were analyzed in the 1500 bp promoter region of DEGs. The results showed that the methylation level of ABRE and CAAT-box acting elements in the promoter region of GST gene involved in plant glutathione metabolism were reduced through DNA demethylation under drought stress. Then the expression was activated in response to drought stress. Therefore, DEGs under drought and DNA demethylation treatments could be analyzed using comparative transcriptomic, and then the genes related to DNA methylation involved in regulating drought stress response in potato could be found. These results provide a new idea for further studying the epigenetic mechanism of drought stress response in potato.

Crop production is threatened by low phosphorus (P) availability and weed interference. Obtaining plant genotypes that can utilize Phosphite (Phi) as fertilizer can supplement phosphates (Pi) while providing an environmentally friendly means of weed control. The study was conducted to determine the tolerance and enzymatic behavior of five potato genotypes to PO3. Explants were regenerated in vitro from two nodal cuttings and cultured on Murashige and Skoog (MS) medium under controlled conditions for 30 days. Matured plantlets were subcultured for 20 days in MS medium containing (0.25, 0.5 mM) Phi and Pi and No-P (-Phi + -Pi). The results showed significant genotypic variation in tolerance indices among the five genotypes. Atlantic showed greater tolerance to Phi, with highest total root length (50.84%), root projected area (75.09%), root surface area (68.94%), root volume (33.49%) and number of root forks (75.66%). Phi induced an increasing trend in the levels of hydrogen peroxide in the genotypes with the least effect in Atlantic. The comprehensive evaluation analysis confirmed the tolerance of Atlantic genotype with this ranking; Atlantic, Longshu3, Qingshu9, Longshu6 and Gannong2. Antioxidant enzyme activities and proline content also increased significantly under Phi and No-P treatments. The results suggested that potato genotypes with larger root systems may be more tolerant to Phi than genotypes with smaller root systems.

研究利用最新报道(2020年)的杂合二倍体马铃薯'RH89-039-16'基因组信息鉴定出23个马铃薯StSnRK2家族成员,分别被命名为StSnRK2.1～StSnRK2.23.通过生物信息学方法,分析了其基因结构、保守基序、理化性质、共线性关系,研究了其与水稻、玉米和拟南芥的SnRK2的系统进化关系,并利用转录组测序技术探究了家族成员在不同逆境胁迫下的基因表达规律.结果表明,马铃薯StSnRK2家族成员不均匀地分布在12条染色体上,家族成员蛋白长度为298～491 aa,分子量为32.6～55.4 kD,等电点4.51～9.47.系统进化树分析发现该基因家族可分为3个亚族,分别含有13、8和2个StSnRK2基因,在这些成员中共找到10个保守基序,其中保守基序1～9均包含于3个亚组中,而保守基序10则特异性分布于亚组Ⅰ.23个StSnRK2成员的表达模式表明,有15个基因在ABA胁迫24 h时表达量发生显著上调,证明这部分基因对马铃薯响应ABA胁迫具有重要的作用.这些结果为阐明StSnRK2基因家族的进化关系和进一步研究StSnRK2基因的功能特性提供了有价值的信息.