PEG Treatment Research Articles

Expression analysis of CsNAC30 gene in cucumber under drought stress

This study performed a bioinformatics analysis of the CsNAC30 gene and examined its expression levels in cucumber leaves and roots under drought stress induced by PEG-6000. The bioinformatics analysis showed that the open reading frame (ORF) of CsNAC30 is 1254 bp, encoding a protein consisting of 417 amino acids. This protein is relatively unstable and hydrophilic, lacks transmembrane regions, and contains 49 phosphorylation sites. It also features a conserved NAM domain at the N-terminus. Homology and phylogenetic analyses indicate that CsNAC30 is a member of the NAC transcription factor family and is most closely related to the melon CMeNAC105 and the winter melon BhNAC96. Quantitative real-time PCR (qPCR) revealed that CsNAC30 expression is induced by drought stress, with relative levels increasing in both leaves and roots following PEG treatment. Expression peaked at 6 h in leaves and 9 h in roots before decreasing. These findings suggest that CsNAC30 plays a role in the cucumber’s response to drought stress.

Epigenomic studies in sorghum reveal differential enrichment of multiple histone marks at clade A PP2C genes in response to drought

Epigenetic regulation is essential for plant development and stress responses, as numerous stress-responsive genes are modulated epigenetically. However, most research has focused on individual histone marks. This study expands on previous work by examining the genome-wide profiles of seven histone marks (H3K9ac, H3K27ac, H3K4me3, H3K36me3, H3K27me3, H2A.Z, and H3K4me2) in sorghum leaves and roots under PEG-induced drought stress. Results revealed that five histone marks (excluding H3K36me3 and H3K27me3) were significantly associated with drought-responsive gene expression. The differential enrichment of these marks may enhance the induction of drought-responsive genes. Specifically, a subset of genes showed multiple histone marks' differential enrichment, with most clade A PP2C genes exhibiting enrichment for four marks after PEG treatment. This suggests a critical role for robust PP2C gene induction in sorghum’s drought response. Additionally, promoter cis-element analysis identified ERF family transcription factors as potential mediators of histone mark enrichment under drought conditions, providing new insights into the interaction between epigenetic modifications and transcriptional regulation in plant stress responses.

Genome-wide identification of the eggplant jasmonate ZIM-domain (JAZ) gene family and functional characterization of SmJAZ10 in modulating chlorophyll synthesis in leaves.

The jasmonate ZIM-domain (JAZ) plays a crucial role in regulating several economic traits in crops. Despite its importance, the characterization of the SmJAZ gene family in eggplant (Solanum melongena L.) has not been documented. In this study, we identified 13 SmJAZ distributed across 9 chromosomes, which were categorized into 5 subgroups based on phylogenetic analysis. Both of them possess TIFY-motif and CCT_2 domains with varying degrees of variation. Promoter cis-element analysis predicted 42 distributed cis-elements that respond to diverse signals. Gene expression analysis demonstrated that SmJAZ exhibited responsiveness to JA, ABA, NaCl, PEG, 4 °C, blue light, and UV-B treatments. Moreover, microRNA interaction predictions identified 150 potential miRNAs, among which ath-miR5021 was found to target 8 SmJAZ mRNAs. Yeast two-hybrid assays demonstrated that most of the SmJAZs were able to interact with SmMYC2 and SmNINJA and could form JAZ-JAZ complexes. Subcellular localization analysis unveiled a diverse array of intranuclear and extranuclear localization signals for SmJAZs. Overexpressing of SmJAZ10 could decrease the chlorophyll content of seedling leaves, and the transcriptome showed that genes related to chlorophyll synthesis, such as SmCHLH, SmPORA, and SmGLK2, underwent down-regulated expression. Overall, these findings serve as a valuable resource for leveraging JA signaling to enhance eggplant quality.

Genome-wide identification and expression analysis of CASPL gene family in Zea mays (L.).

Casparian strip membrane domain proteins like (CASPL), exhibit profound associations with root development, stress responsiveness and mineral element uptake in plants. Nonetheless, a comprehensive bioinformatics analysis of the ZmCASPL gene family in maize remains unreported. In the study, we have identified 47 ZmCASPL members at the whole-genome level, systematically classifying them into six distinct groups. Furthermore, our analysis revealed that the same group of ZmCASPL contains similar gene structures and conserved motifs. Duplication events showed whole genome duplication (WGD) and tandem duplication (TD) contribute to the generation of the ZmCASPL gene family together in maize, but the former plays a more prominent role. Furthermore, we observed that most ZmCASPL genes contain MYB-binding sites (CAACCA), which are associated with the Casparian strip. Utilizing RNA-seq data, we found that ZmCASPL21 and ZmCASPL47 are specifically highly expressed only in the roots. This finding implies that ZmCASPL21 and ZmCASPL47 may be involved in the Casparian strip development. Additionally, RNA-seq analysis illuminated that drought, salt, heat, cold stresses, low nitrogen and phosphorus conditions, as well as pathogen infection, significantly impact the expression patterns of ZmCASPL genes. RT-qPCR revealed that ZmCASPL 5/13/25/44 genes showed different expression patterns under PEG and NaCl treatments. Collectively, these findings provide a robust theoretical foundation for further investigations into the functional roles of the ZmCASPL gene family in maize.

Comparative analysis of the NF-Y transcription factor family identifies VaNF-YA6 as a positive regulator of salt and drought tolerance in grapevine

Nuclear factor Y transcription factors (NF-Y TFs) play crucial roles in plant responses to abiotic stress. However, there is a lack of research on the comparative analysis of evolutionary relationships, real-time quantitative fluorescence PCR (RT-qPCR), and functions of NF-Y TFs to screen key NF-Y TFs that are resistant to salt and drought stresses between Vitis vinifera (V. vinifera) and Vitis amurensis (V. amurensis). In this study, 27 and 26 NF-Y TFs were identified in V. vinifera and V. amurensis, respectively, and were divided into three subgroups. Subcellular localization prediction revealed that NF-Ys TFs were mainly located in the nucleus. Interestingly, the NF-YA protein sequence of ‘NTKKLDWEFWGCCDDCEKWFGGCC’ was lost in the V. vinifera compared to V. amurensis, whereas the sequence ‘SSVYSQPWWGHSIVCVA’ was gained, thus, these sequences might be closely related to the functions performed. RT-qPCR analysis of ‘Pinot Noir’ (cultivated variety) and ‘Zuoyouhong’ (wild variety) plantlets demonstrated that the expression levels of VaNF-YA6, VaNF-YB5, VvNF-YA3, VvNF-YA5, and VvNF-YC2 were significantly upregulated under 400 mmol·L-1 NaCl and 10% PEG treatments for 24 h Subcellular localization showed that the VaNF-YA6-GFP fusion protein was functioned primarily in the nucleus. Overexpression of VaNF-YA6 in grapevine leaves and Arabidopsis thaliana (Arabidopsis) could significantly enhance tolerance to salt and drought stresses by improving VvSOS2, VvSOS3, VvABF3, VvCPK6 expression levels, enzyme activities, and other protective substances. In summary, our study provides a theoretical basis for the further use of VaNF-YA6 to improve salt and drought resistance in grapevines.

The synergistic potential of polyethylene glycol 400 for the control of Hyphantria cunea larvae by Beauveria bassiana

The efficacy of entomopathogenic fungi as pest control agents is constrained by both their physiological state and external environmental factors. This study identified synergists capable of enhancing the insecticidal activity of Beauveria bassiana (Bb) and investigated the underlying synergistic mechanisms. Our results found that among 6 potential synergists, polyethylene glycol 400 (PEG) and trehalose significantly improved Bb's lethality against Hyphantria cunea larvae, with PEG demonstrating the most pronounced effect. PEG treatment markedly increased Bb spore adhesion and germination rates, while spore hydrophobicity and growth rates remained unaffected. Moreover, PEG-treated spores exhibited higher thermal tolerance compared to untreated ones. In the Bb + PEG treatment group, the hemocyte count, encapsulation and melanization activities, and the expression of related regulatory genes were significantly lower than those in the Bb treatment group. Additionally, pathogen recognition, signal transduction, and humoral immunity effector genes expression were markedly suppressed in the Bb + PEG group. A significant reduction in the content of total amino acids, free fatty acids, glucose, and trehalose, alongside decreased expression of key regulatory genes in the tricarboxylic acid cycle and glycolysis pathways, was observed in the Bb + PEG treatment group. Furthermore, PEG enhanced Bb-induced apoptosis in H. cunea larvae, as evidenced by the upregulation of apoptosis-related genes. Notably, PEG alone did not significantly impact the innate immunity, energy metabolism, or apoptosis in H. cunea larvae. Overall, PEG exhibits considerable potential in amplifying Bb's insecticidal activity by directly optimizing spore performance and indirectly modulating the larvae's innate immunity, energy metabolism, and apoptosis.

Comprehensive characterization of gibberellin oxidase gene family in Brassica napus reveals BnGA2ox15 involved in hormone signaling and response to drought stress

Brassica napus is a well-known allopolyploid oil crop with high commercial potential. Gibberellin oxidase (GAox) is an essential enzyme that activates gibberellins, which regulate plant growth, and development, and have a significant impact on plant responses to abiotic stress. However, the comprehensive understanding of GAox genes and their evolution in Brassica plants remains elusive. Using advanced bioinformatics tools, this study identified 125 candidate GAox genes from the whole genomes of three key Brassica species. This study also investigated sequence characteristics, conserved motifs, exon/intron structures, cis-acting elements, syntenic analysis, duplication events and expression patterns. Subcellular localization analysis showed that the BnGA2ox14 and BnGA2ox15 proteins are located in the nucleus, whereas BnGA2ox26 is specifically localized to the chloroplast. Yeast one-hybrid and dual-luciferase assays demonstrated that MYELOCYTOMATOSIS 4 (BnMYC4) and ABA-INDUCIBLE BHLH-TYPE TRANSCRIPTION FACTOR (BnAIB) bind to the BnGA2ox15 promoter and activate its transcription. Molecular docking analysis further elucidated their interaction structures and identified potential binding sites. Roots transformations show that overexpression of BnGA2ox15 increased sensitivity to PEG-6000 treatment in rapeseed. In brief, this study reveals that BnGA2ox15 is a downstream target in JA and ABA signaling pathways, functioning as a negative regulator in response to drought stress.

Determination of the effects of drought stress on Aronia melanocarpa cv. Nero in vitro conditions

Drought stress is a significant threat to plant cultivation in arid and semi-arid regions, negatively affecting growth and leading to plant mortality. This study evaluated the in vitro drought tolerance of Aronia melanocarpa ‘Nero’ by exposing micropropagated plantlets to nutrient media containing different concentrations of PEG-8000 (0%, 1%, and 2%) during the rooting stage. Results showed that increasing PEG concentrations led to a reduction in survival, rooting, plantlet growth, and physiological parameters. The 0% PEG treatment resulted in the highest survival rate (95.83%), root number, and chlorophyll content, while the 2% PEG treatment significantly hindered these parameters. These findings indicate that Aronia melanocarpa 'Nero' is sensitive to drought stress, with reduced growth and physiological activity under higher PEG concentrations.

Genome-wide identification of the endonuclease family genes implicates potential roles of TaENDO23 in drought-stressed response and grain development in wheat

BackgroundEndonucleases play a crucial role in plant growth and stress response by breaking down nuclear DNA. However, the specific members and biological functions of the endonuclease encoding genes in wheat remain to be determined.ResultsIn this study, we identified a total of 26 TaENDO family genes at the wheat genome-wide level. These genes were located on chromosomes 2 A, 2B, 2D, 3 A, 3B, and 3D and classified into four groups, each sharing similar gene structures and conserved motifs. Furthermore, we identified diverse stress-response and growth-related cis-elements in the promoter of TaENDO genes, which were broadly expressed in different organs, and several TaENDO genes were significantly induced under drought and salt stresses. We further examined the biological function of TaENDO23 gene since it was rapidly induced under drought stress and exhibited high expression in spikes and grains. Subcellular localization analysis revealed that TaENDO23 was localized in the cytoplasm of wheat protoplasts. qRT-PCR results indicated that the expression of TaENDO23 increased under PEG6000 and abscisic acid treatments, but decreased under NaCl treatment. TaENDO23 mainly expressed in leaves and spikes. A kompetitive allele-specific PCR (KASP) marker was developed to identify single nucleotide polymorphisms in TaENDO23 gene in 256 wheat accessions. The alleles with TaENDO23-HapI haplotypes had higher grain weight and size compared to TaENDO23-HapII. The geographical and annual frequency distributions of the two TaENDO23 haplotypes revealed that the elite haplotype TaENDO23-HapI was positively selected in the wheat breeding process.ConclusionWe systematically analyzed the evolutionary relationships, gene structure characteristics, and expression patterns of TaENDO genes in wheat. The expression of TaENDO23, in particular, was induced under drought stress, mainly expressed in the leaves and grains. The KASP marker of TaENDO23 gene successfully distinguished between the wheat accessions, revealing TaENDO23-HapI as the elite haplotype associated with improved grain weight and size. These findings provide insights into the evolution and characteristics of TaENDO genes at the genome-wide level in wheat, laying the foundation for further biological analysis of TaENDO23 gene, especially in response to drought stress and grain development.

Molecular Characterization of Peroxidase (PRX) Gene Family in Cucumber.

Background: The Peroxidase (PRX) gene family is essential for plant growth and significantly contributes to defense against stresses. However, information about PRX genes in cucumber (Cucumis sativus L.) remains limited. Methods: In this present study, CsPRX genes were identified and characterized using bioinformatics analysis. The expression pattern analysis of CsPRX genes were examined utilizing the RNA-seq data of cucumber from public databases and real-time quantitative PCR (qRT-PCR) analysis. Results: Here, we identified 60 CsPRX genes and mapped them onto seven chromosomes of cucumber. The CsPRX proteins exhibited the presence of 10 conserved motifs, with motif 8, motif 2, motif 5, and motif 3 consistently appearing across all 60 CsPRX protein sequences, indicating the conservation of CsPRX proteins. Furthermore, RNA-seq analysis revealed that differential expression of CsPRX genes in various tissues. Notably, a majority of the CsPRX genes exhibited significantly higher expression levels in the root compared to the other plant tissues, suggesting a potential specialization of these genes in root function. In addition, qRT-PCR analysis for four selected CsPRX genes under different stress conditions indicated that these selected CsPRX genes demonstrated diverse expression levels when subjected to NaCl, CdCl2, and PEG treatments, and the CsPRX17 gene was significantly induced by NaCl, CdCl2, and PEG stresses, suggesting a vital role of the CsPRX17 gene in response to environmental stresses. Conclusions: These findings will contribute valuable insights for future research into the functions and regulatory mechanisms associated with CsPRX genes in cucumber.

PEG treatment is unsuitable to study root related traits as it alters root anatomy in barley (Hordeum vulgare L.)

BackgroundThe frequency and severity of abiotic stress events, especially drought, are increasing due to climate change. The plant root is the most important organ for water uptake and the first to be affected by water limitation. It is therefore becoming increasingly important to include root traits in studies on drought stress tolerance. However, phenotyping under field conditions remains a challenging task. In this study, plants were grown in a hydroponic system with polyethylene glycol as an osmotic stressor and in sand pots to examine the root system of eleven spring barley genotypes. The root anatomy of two genotypes with different response to drought was investigated microscopically.ResultsRoot diameter increased significantly (p < 0.05) under polyethylene glycol treatment by 54% but decreased significantly (p < 0.05) by 12% under drought stress in sand pots. Polyethylene glycol treatment increased root tip diameter (51%) and reduced diameter of the elongation zone (14%) compared to the control. Under drought stress, shoot mass of plants grown in sand pots showed a higher correlation (r = 0.30) with the shoot mass under field condition than polyethylene glycol treated plants (r = -0.22).ConclusionThese results indicate that barley roots take up polyethylene glycol by the root tip and polyethylene glycol prevents further water uptake. Polyethylene glycol-triggered osmotic stress is therefore unsuitable for investigating root morphology traits in barley. Root architecture of roots grown in sand pots is more comparable to roots grown under field conditions.

Superior osmotic stress tolerance in oilseed rape transformed with wild-type Rhizobium rhizogenes

Key messageNatural transformation with R. rhizogenes enhances osmotic stress tolerance in oilseed rape through increasing osmoregulation capacity, enhancing maintenance of hydraulic integrity and total antioxidant capacity.Transformation of plants using wild strains of agrobacteria is termed natural transformation and is not covered by GMO legislation in, e.g., European Union and Japan. In this study, offspring lines of Rhizobium rhizogenes naturally transformed oilseed rape (Brassica napus), i.e., A11 and B3 (termed root-inducing (Ri) lines), were investigated for osmotic stress resilience. Under polyethylene glycol 6000 (PEG) 10% (w/v)-induced osmotic stress, the Ri lines, particularly A11, had less severe leaf wilting, higher stomatal conductance (8.2 times more than WT), and a stable leaf transpiration rate (about 2.9 mmol m−2 s−1). Although the leaf relative water content and leaf water potential responded similarly to PEG treatment between the Ri lines and WT, a significant reduction of the turgid weight to dry weight ratio in A11 and B3 indicated a greater capacity of osmoregulation in the Ri lines. Moreover, the upregulation of plasma membrane intrinsic proteins genes (PIPs) in roots and downregulation of these genes in leaves of the Ri lines implied a better maintenance of hydraulic integrity in relation to the WT. Furthermore, the Ri lines had greater total antioxidant capacity (TAC) than the WT under PEG stress. Collectively, the enhanced tolerance of the Ri lines to PEG-induced osmotic stress could be attributed to the greater osmoregulation capacity, better maintenance of hydraulic integrity, and greater TAC than the WT. In addition, Ri-genes (particularly rolA and rolD) play roles in response to osmotic stress in Ri oilseed rape. This study reveals the potential of R. rhizogenes transformation for application in plant drought resilience.

Genome-wide analysis of the HD-Zip IV gene family in Camellia sinensis and functional characterization of CsHDZIV3 under trichome development

The HD-Zip IV transcription factors, which belong to the homeodomain leucine zipper (HD-ZIP) family, are essential for the development of epidermal cells in plants. However, there is limited information about HD-Zip IV in tea plant (Camellia sinensis L.). Here we identified 10 HD-Zip IV members (CsHDZIV1∼10) in tea plant, which are distributed in 8 chromosomes with two segmentally duplicated gene pairs. The exon number of CsHDZIVs ranges from 9 to 11, with most genes having two conserved motifs in the 3’UTR. CsHDZIV1∼9 have almost identical motifs and tertiary structures. The promoter region of CsHDZIVs was predicted to harbor light, phytohormone, stress, growth and developmental elements. 9 CsHDZIVs are divided into 5 subfamilies and located in the nucleus. They exhibited expression trends across 12 tea plant tissues and responded to PEG, cold, NaCl and shading treatments. CsHDZIV3 overexpression partially and completely restored trichome development defects of gl2 leaves and stems, respectively. CsHDZIV3 showed histochemical staining in Arabidopsis trichomes and protein interaction with itself. It might regulate trichome development through forming homodimers. These findings contribute to functional study of tea plant HD-Zip IV and provide guiding significance for the investigation of trichome development and the improvement of trichome traits.

Physiological, Metabolome and Gene Expression Analyses Reveal the Accumulation and Biosynthesis Pathways of Soluble Sugars and Amino Acids in Sweet Sorghum under Osmotic Stresses.

Water scarcity is a major environmental constraint on plant growth in arid regions. Soluble sugars and amino acids are essential osmolytes for plants to cope with osmotic stresses. Sweet sorghum is an important bioenergy crop and forage with strong adaptabilities to adverse environments; however, the accumulation pattern and biosynthesis basis of soluble sugars and amino acids in this species under osmotic stresses remain elusive. Here, we investigated the physiological responses of a sweet sorghum cultivar to PEG-induced osmotic stresses, analyzed differentially accumulated soluble sugars and amino acids after 20% PEG treatment using metabolome profiling, and identified key genes involved in the biosynthesis pathways of soluble sugars and amino acids using transcriptome sequencing. The results showed that the growth and photosynthesis of sweet sorghum seedlings were significantly inhibited by more than 20% PEG. After PEG treatments, the leaf osmotic adjustment ability was strengthened, while the contents of major inorganic osmolytes, including K+ and NO3-, remained stable. After 20% PEG treatment, a total of 119 and 188 differentially accumulated metabolites were identified in the stems and leaves, respectively, and the accumulations of soluble sugars such as raffinose, trehalose, glucose, sucrose, and melibiose, as well as amino acids such as proline, leucine, valine, serine, and arginine were significantly increased, suggesting that these metabolites should play key roles in osmotic adjustment of sweet sorghum. The transcriptome sequencing identified 1711 and 4978 DEGs in the stems, as well as 2061 and 6596 DEGs in the leaves after 20% PEG treatment for 6 and 48 h, respectively, among which the expressions of genes involved in biosynthesis pathways of sucrose (such as SUS1, SUS2, etc.), trehalose (including TPS6), raffinose (such as RAFS2 and GOLS2, etc.), proline (such as P5CS2 and P5CR), leucine and valine (including BCAT2), and arginine (such as ASS and ASL) were significantly upregulated. These genes should be responsible for the large accumulation of soluble sugars and amino acids under osmotic stresses. This study deepens our understanding of the important roles of individual soluble sugars and amino acids in the adaptation of sweet sorghum to water scarcity.

Decoding the role of OsPRX83 in enhancing osmotic stress tolerance in rice through ABA-dependent pathways and ROS scavenging

ABSTRACT Plant Class III peroxidases have diverse roles in controlling root hair growth, anther development, and abiotic and biotic stress responses. However, their abiotic stress response mechanism in rice remains elusive. Here, we identified a peroxidase precursor gene, OsPRX83, and investigated its role in enhancing osmotic stress tolerance in rice. We used OsPRX83 overexpression and CRISPR-Cas9-generated mutant lines to elucidate OsPRX83‘s function and expression patterns under stress conditions. The expression of OsPRX83 was induced by H2O2, PEG, NaCl, and ABA treatments. Using qRT-PCR, RNA sequencing, and physiological assays, we demonstrated that overexpression of OsPRX83 enhanced the osmotic and oxidative stress tolerance as compared to the wild-type and mutant seedlings, as evident from the higher survival rates, enhanced peroxidase (POD) and ascorbate peroxidase (APX) activities, and increased ABA sensitivity compared with mutants and wild-type plants. Transcriptome analysis further supported the involvement of OsPRX83 in the ROS scavenging, by modulating the expression of OsDREB1B, OsDREB1E, OsDREB1F, OsDREB1G in response to osmotic treatment. In summary, our study suggests that OsPRX83 plays a pivotal role in enhancing stress tolerance in rice through ABA-dependent pathways and ROS scavenging. Therefore, this study elucidates the function of a novel abiotic stress response gene in rice, thereby may contribute to a new genetic engineering resource for engineering drought-resistant rice varieties.

Expression of Foxtail Millet bZIP Transcription Factor SibZIP67 Enhances Drought Tolerance in Arabidopsis.

Foxtail millet is a drought-tolerant cereal and forage crop. The basic leucine zipper (bZIP) gene family plays important roles in regulating plant development and responding to stresses. However, the roles of bZIP genes in foxtail millet remain largely uninvestigated. In this study, 92 members of the bZIP transcription factors were identified in foxtail millet and clustered into ten clades. The expression levels of four SibZIP genes (SibZIP11, SibZIP12, SibZIP41, and SibZIP67) were significantly induced after PEG treatment, and SibZIP67 was chosen for further analysis. The studies showed that ectopic overexpression of SibZIP67 in Arabidopsis enhanced the plant drought tolerance. Detached leaves of SibZIP67 overexpressing plants had lower leaf water loss rates than those of wild-type plants. SibZIP67 overexpressing plants improved survival rates under drought conditions compared to wild-type plants. Additionally, overexpressing SibZIP67 in plants displayed reduced malondialdehyde (MDA) levels and enhanced activities of antioxidant enzymes, including catalase (CAT), superoxide dismutase (SOD), and peroxidase (POD) under drought stress. Furthermore, the drought-related genes, such as AtRD29A, AtRD22, AtNCED3, AtABF3, AtABI1, and AtABI5, were found to be regulated in SibZIP67 transgenic plants than in wild-type Arabidopsis under drought conditions. These data suggested that SibZIP67 conferred drought tolerance in transgenic Arabidopsis by regulating antioxidant enzyme activities and the expression of stress-related genes. The study reveals that SibZIP67 plays a beneficial role in drought response in plants, offering a valuable genetic resource for agricultural improvement in arid environments.

Effect of seed priming with polyethylene glycol, distilled water, and sorbitol on physical, chemical quality parameters, and nodule microbiota of lentil.

The aim of this study was to investigate the effects of different seed priming solutions on physical and chemical quality parameters of lentils as well as nodule bacterial diversity before sowing. Therefore, lentil seeds were treated with polyethylene glycol (PEG 6000) (15%), sorbitol (6%), and distilled water, and none pretreated lentils (Lens culinaris) were used as control. The seeds were kept in these solutions for 24h, then dried on toweling paper for 24h, and used for the experiment. For nodule microbiota analysis, the plant root was divided into two equal parts, upper and lower, according to the root length and all nodules were collected from each region. According to the results, it was observed that emergence and flowering started late in the control compared to other seed priming treatments. Sorbitol application was found to provide advantages in terms of germination and seedling development. PEG and distilled water (DW) treatments showed an increase in total phenolic component activity; however, no significant change was observed in DPPH radical scavenging activity. Amplicon-based metagenomic analysis revealed that sorbitol and distilled water were the seed priming solutions altering the species diversity, especially Rhizobium sp. as the genus. In the comparison of samples taken from different parts of the root nodules, more Rhizobium sp. as a genus and Rhizobium leguminosarum as the species were found in the nodules collected from the top of the root. According to the overall results of lentil pod, lentil plant, and microbiota, sorbitol and DW can be considered to be a good priming solutions.

O-Glycosyltransferase Gene BnaC09.OGT Involved in Regulation of Unsaturated Fatty Acid Biosynthesis for Enhancing Osmotic Stress Tolerance in Brassica napus L.

Osmotic stress is a major threaten to the growth and yield stability of Brassica napus. Post-translational modification with O-linked β-N-acetylglucosamine (O-GlcNAc) is ubiquitous in plants, and participates in a variety of signal transduction and metabolic regulation. However, studies on the role of O-GlcNAc transferase (OGT) in osmotic stress tolerance of plants are limited. In previous study, a O-glycosyltransferase, named BnaC09.OGT, was identified from the B. napus variety 'Zhongshuang 11' by yeast one hybrid with promoter of BnaA01.GPAT9. It was found that BnaC09.OGT localized in both nucleus and cytoplasm. The spatiotemporal expression pattern of BnaC09.OGT exhibited tissue specificity in developmental seed, especially in 15 days after pollination. In view of osmotic stress inducing, the BnaC09.OGT overexpression and knockout transgenic lines were constructed for biological function study. Phenotypic analysis of BnaC09.OGT overexpression seedlings demonstrated that BnaC09.OGT could enhance osmotic stress tolerance than WT and knockout lines in euphylla stage under 15% PEG6000 treatment after 7 days. In addition, compared with WT and knockout lines, overexpression of BnaC09.OGT had significantly higher activities of antioxidant enzymes (SOD and POD), higher content of soluble saccharide, and while significantly less content of malondialdehyde, proline and anthocyanidin under 15% PEG6000 treatment after 7 days. On the other hand, the unsaturated fatty acid content of BnaC09.OGT overexpression was significantly higher than that of WT and knockout lines, so it is speculated that the BnaC09.OGT could increase unsaturated fatty acid biosynthesis for osmotic stress tolerance by promoting the expression of BnaA01.GPAT9 in glycerolipid biosynthesis. In summary, the above results revealed that the function of BnaC09.OGT provides new insight for the analysis of the pathway of O-glycosylation in regulating osmotic stress tolerance in B. napus.

Genome-wide analysis of soybean hypoxia inducible gene domain containing genes: a functional investigation of GmHIGD3.

The response of Hypoxia Inducible Gene Domain (HIGD) proteins to hypoxia plays a crucial role in plant development. However, the research on this gene family in soybean has been lacking. In this study, we aimed to identify and comprehensively analyze soybean HIGD genes using the Glycine max genome database. As a result, six GmHIGD genes were successfully identified, and their phylogeny, gene structures, and putative conserved motifs were analyzed in comparison to Arabidopsis and rice. Collinearity analysis indicated that the HIGD gene family in soybean has expanded to some extent when compared to Arabidopsis. Additionally, the cis-elements in the promoter regions of GmHIGD and the transcription factors potentially binding to these regions were identified. All GmHIGD genes showed specific responsiveness to submergence and hypoxic stresses. Expression profiling through quantitative real-time PCR revealed that these genes were significantly induced by PEG treatment in root tissue. Co-expressed genes of GmHIGD were primarily associated with oxidoreductase and dioxygenase activities, as well as peroxisome function. Notably, one of GmHIGD genes, GmHIGD3 was found to be predominantly localized in mitochondria, and its overexpression in Arabidopsis led to a significantly reduction in catalase activity compared to wild-type plants. These results bring new insights into the functional role of GmHIGD in terms of subcellular localization and the regulation of oxidoreductase activity.

Comparative Cytological and Gene Expression Analysis Reveals That a Common Wild Rice Inbred Line Showed Stronger Drought Tolerance Compared with the Cultivar Rice.

Common wild rice (Oryza rufipogon Griff.) is an important germplasm resource containing valuable genes. Our previous analysis reported a stable wild rice inbred line, Huaye3, which derives from the common wild rice of Guangdong Province. However, there was no information about its drought tolerance ability. Here, we assessed the germination characteristics and seedling growth between the Dawennuo and Huaye3 under five concentrations of PEG6000 treatment (0, 5%, 10%, 15%, and 20%). Huaye3 showed a stronger drought tolerance ability, and its seed germination rate still reached more than 52.50% compared with Dawennuo, which was only 25.83% under the 20% PEG6000 treatment. Cytological observations between the Dawennuo and Huaye3 indicated the root tip elongation zone and buds of Huaye3 were less affected by the PEG6000 treatment, resulting in a lower percentage of abnormalities of cortical cells, stele, and shrinkage of epidermal cells. Using the re-sequencing analysis, we detected 13,909 genes that existed in the genetic variation compared with Dawennuo. Of these genes, 39 were annotated as drought stress-related genes and their variance existed in the CDS region. Our study proved the strong drought stress tolerance ability of Huaye3, which provides the theoretical basis for the drought resistance germplasm selection in rice.