Application of wheat gene TaSNAC11 in improving plant salt tolerance

Abstract

The application discloses application of a wheat gene TaSNAC11 in improving plant salt tolerance, and belongs to the technical field of functional genomics. The nucleotide sequence of the wheat gene TaSNAC11 is shown in SEQ ID NO:2, and the gene can improve the salt stress tolerance of plants. The application has the advantages that the wheat gene TaSNAC11 is transformed into a model plant Arabidopsis thaliana, and the salt tolerance of the Arabidopsis thaliana can be obviously improved. If the wheat gene TaSNAC11 is transformed into plants such as wheat, rice, corn and cauliflower, new germplasm with salt tolerance characteristics can be obtained, and the application has important significance for cultivation of excellent crop new varieties and wide application of the excellent crop new varieties in production.

Description

Technical Field

[0001] The present invention relates to an application of a gene, in particular to an application of the wheat gene TaSNAC11 in improving plant salt tolerance, and belongs to the technical field of functional genomics. Background Art

[0002] Salt stress is a serious adverse environmental factor that can cause osmotic stress, cell ion toxicity, and oxidative stress to crops, leading to seed germination inhibition, decreased photosynthetic performance, and stagnant growth and development, seriously affecting crop yields. China's land salinization area has reached 100 million hm2. 2 , and is still on the rise. Wheat ( Triticum aestivum As an important grain crop in my country, wheat occupies a strategically important position in ensuring national food security. Soil salinization has become a major factor hindering wheat growth and yield in my country. Therefore, improving wheat's salt tolerance is a crucial approach to ensuring national food security. Breeding salt-tolerant varieties is an effective measure to improve wheat salt tolerance, and further identifying key salt-tolerance genes is a scientific and rational biotechnology approach to breeding salt-tolerant varieties. Summary of the Invention

[0003] The present invention screened and cloned the wheat gene TaSNAC11 from Chinese Spring (CS) wheat, and confirmed that the gene can effectively improve the salt tolerance of Arabidopsis thaliana.

[0004] In order to achieve the above objectives, the present invention adopts the following technical solutions:

[0005] The invention discloses an application of the wheat gene TaSNAC11 in improving plant salt tolerance. The nucleotide sequence of the wheat gene TaSNAC11 is shown in SEQ ID NO: 2. The gene can improve plant tolerance to salt stress.

[0006] Preferably, the aforementioned application comprises the following steps:

[0007] (1) PCR amplification and cloning of the wheat gene TaSNAC11;

[0008] (2) The cloned wheat gene TaSNAC11 was linked into an expression vector to obtain an overexpression recombinant vector;

[0009] (3) Transforming the overexpression recombinant vector into Agrobacterium to obtain an overexpression recombinant strain;

[0010] (4) The overexpression recombinant strain was transformed into plants, and the wheat gene TaSNAC11 overexpression strain was screened and obtained.

[0011] More preferably, the aforementioned expression vector is super1300 (GFP-C); and the aforementioned Agrobacterium is Agrobacterium tumefaciens GV3101.

[0012] The wheat gene TaSNAC11 is transformed into the model plant Arabidopsis thaliana, and the salt tolerance of Arabidopsis thaliana is obviously improved, and the wheat gene TaSNAC11 is transformed into wheat, rice, corn, cauliflower and other plants, and new germplasm with salt tolerance characteristics can be obtained, which has important significance for the cultivation of excellent crop new varieties and the wide application of excellent crop new varieties in production. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 is a structural schematic diagram of the target vector super1300 (GFP-C);

[0014] Figure 2 is a PCR identification diagram of the TaSNAC11 overexpression transgenic Arabidopsis thaliana strain (OE1, OE2);

[0015] Figure 3 is a relative expression amount statistical diagram of the TaSNAC11 overexpression transgenic Arabidopsis thaliana strain (OE1, OE2) and the wild type (WT) gene TaSNAC11 of the Columbia ecotype Arabidopsis thaliana;

[0016] Figure 4 is a germination rate statistical diagram of the TaSNAC11 overexpression transgenic Arabidopsis thaliana seed (OE1, OE2) and the wild type Arabidopsis thaliana seed (WT) of the Columbia ecotype Arabidopsis thaliana after ABA treatment;

[0017] Figure 5 is a germination rate statistical diagram of the TaSNAC11 overexpression transgenic Arabidopsis thaliana seed (OE1, OE2) and the wild type Arabidopsis thaliana seed (WT) of the Columbia ecotype Arabidopsis thaliana after salt stress treatment;

[0018] Figure 6 is a comparison diagram of the root system growth of each strain under normal conditions (control group);

[0019] Figure 7 is a root length statistical diagram of each strain under normal conditions (control group);

[0020] Figure 8 is a comparison diagram of the root system growth of each strain under salt stress treatment;

[0021] Figure 9 is a root length statistical diagram of each strain under salt stress treatment;

[0022] Figure 10 is a plant height statistical diagram of each strain under normal conditions and under salt stress treatment;

[0023] Figure 11 It is a statistical graph of fresh weight of each strain under normal conditions and under salt stress treatment conditions;

[0024] Figure 12 It is the statistical graph of dry weight of each strain under normal conditions and under salt stress treatment conditions;

[0025] Figure 13 It is the statistical graph of relative conductivity of each strain under normal conditions and under salt stress treatment conditions;

[0026] Figure 14 It is a statistical graph of chlorophyll content of each strain under normal conditions and under salt stress treatment conditions;

[0027] Figure 15 It is the statistical graph of SOD activity of each strain under normal conditions and under salt stress treatment conditions;

[0028] Figure 16 It is a statistical graph of POD activity of each strain under normal conditions and under salt stress treatment conditions. DETAILED DESCRIPTION

[0029] The present invention will be described in detail below with reference to the accompanying drawings and examples. The reagents, materials, and instruments used in the examples are all commercially available unless otherwise specified. The terms used in the examples, unless otherwise specified, generally have the meanings commonly understood by those of ordinary skill in the art. The experimental methods used in the examples are all conventional methods unless otherwise specified.

[0030] Example 1: Cloning of the wheat gene TaSNAC11

[0031] Wheat is an important food crop with a wide range of cultivation and is also highly adaptable to harsh external environments. This study attempted to screen for salt-tolerance genes in wheat, ultimately identifying a salt-tolerance gene from Chinese Spring (CS) wheat. In the Ensembl Plants database, the gene ID for this gene is TraesCS4A02G131000.1, located on wheat chromosome 4A. The ORF (open reading frame) is 1065 bp, the mRNA is 1657 bp long, and the nucleotide sequence is shown in SEQ ID NO: 2. The encoded product is 354 amino acids in size, has a molecular weight of 38389.46, and an isoelectric point of 9.23. This gene was named TaSNAC11 and cloned using cloning techniques. The specific steps are as follows:

[0032] Total RNA was extracted from leaves of Chinese Spring (CS) wheat grown in hydroponic culture for seven days using the Trizol method. After purification, cDNA was generated using HiScript III RT SuperMix for qPCR (with gDNA wiper). This cDNA was used as a template to amplify the TaSNAC11 gene using the upstream primer L1 shown in SEQ ID NO: 3 and the downstream primer R1 shown in SEQ ID NO: 4. The amplified product was sequenced to determine the nucleotide sequence of the target gene.

[0033] The nucleotide sequences of the upstream primer L1 and the downstream primer R1 are shown below:

[0034] Upstream primer L1: 5′-ATGATCATGTCCGACCCG-3′ (SEQ ID NO: 3);

[0035] Downstream primer R1: 5′-GAAACGGAGCAGCGTCTG-3′ (SEQ ID NO: 4).

[0036] The PCR reaction system for amplifying the TaSNAC11 gene was as follows: ddH2O 8 μL, 2×Phanta Max Master Mix (Dye Plus) 12.5 μL, upstream primer L1 1 μL, downstream primer R1 1 μL, and cDNA template 2.5 μL.

[0037] The PCR reaction conditions for amplifying the TaSNAC11 gene were as follows: 95°C, 3 min; 95°C, 15 s, 59°C, 15 s, 72°C, 30 s, repeated 35 cycles; extension at 72°C for 5 min, and finally storage at 4°C.

[0038] The obtained PCR amplification products were electrophoresed in 1% agarose gel, and the fragments with a sequence length of about 1062 bp were recovered. TM The TA / Blunt-Zero Cloning Kit was ligated to pCE2 TA / Blunt-Zero and transformed into E. coli Fast-T1 competent cells. Positive clones were selected for sequencing.

[0039] Sequencing results showed that a 1062bp DNA fragment was inserted into the pCE2 TA / Blunt-Zero vector. The nucleotide sequence of the DNA fragment, as shown in SEQ ID NO: 2, was consistent with the nucleotide sequence of the gene TraesCS4A02G131000.1 in the Ensembl Plants database, minus the stop codon, and was confirmed to be the full-length cDNA sequence of the wheat gene TaSNAC11.

[0040] Example 2: Construction of recombinant expression vector

[0041] 1. Amplification of target gene

[0042] XbaI restriction sites were added to the 5' ends of upstream primer L1 and downstream primer R1, respectively, to obtain upstream primer L2 and downstream primer R2. The nucleotide sequences of upstream primer L2 and downstream primer R2 are shown below:

[0043] Upstream primer L2:

[0044] 5'-ATACACCAAATCGACTCTAGAATGATCATGTCCGACCCG-3' (SEQ ID NO: 5);

[0045] Downstream primer R2:

[0046] 5'-CATAGGTACCCGGGCTCTAGAGAAACGGAGCAGCGTCTG-3' (SEQ ID NO: 6).

[0047] PCR amplification was performed using the positive Escherichia coli culture containing the pCE2 TA / Blunt-Zero recombinant vector obtained in Example 1 as a template.

[0048] The PCR reaction system was as follows: ddH2O 8 μL, 2×Phanta Max Master Mix (Dye Plus) 12.5 μL, upstream primer L2 1 μL, downstream primer R2 1 μL, and template 2.5 μL.

[0049] The PCR reaction program was as follows: 95°C, 3 min; 95°C, 15 s, 59°C, 15 s, 72°C, 30 s, repeated 35 cycles; extension at 72°C for 5 min, and finally storage at 4°C.

[0050] The PCR product (target gene) with a sequence length of approximately 1062 bp was recovered and used for subsequent reactions.

[0051] 2. Vector linearization

[0052] Using QuickCut TM The target vector super1300 (GFP-C) was linearized with the restriction endonuclease XbaI. The structure of the target vector super1300 (GFP-C) is shown in Figure 1 , and obtain the linearized cloning vector.

[0053] Enzyme digestion system: plasmid 1μg, 10× QuickCut Green Buffer 2μL, QuickCut TMAdd 1 μL of XbaI and add ddH2O to 20 μL.

[0054] Reaction conditions: incubate at 37°C for 3 h.

[0055] 3. Connect the target gene to the cloning vector

[0056] The target gene obtained in step 1 was ligated into the linearized cloning vector obtained in step 2 using the CloneExpress II One-step Cloning Kit (Vayme) to obtain the recombinant expression vector super1300 (GFP-C)-TaSNAC11.

[0057] The ligation system is as follows: linearized super1300 (GFP-C) 3 μL, target gene 1 μL, 5×CE II Buffer 2 μL, Exnase II 1 μL, ddH2O 3 μL.

[0058] Reaction conditions: Use a pipette to gently mix the ligation system, centrifuge briefly to collect the liquid at the bottom of the tube, and react at 37°C for 30 minutes.

[0059] 4. Screening and identification of target gene clones

[0060] The specific steps for screening and identifying target gene clones are as follows:

[0061] (1) Take 10 μL of the recombination reaction product obtained in step 3 and transform it into competent cells of Escherichia coli Fast-T1. Incubate the cells at 37°C for 12 h (LB solid medium supplemented with 50 μg / mL kanamycin sulfate).

[0062] (2) Pick the single clone obtained in step (1) and culture it at 37°C and 180 rpm for 12 h (the culture medium is LB liquid medium supplemented with 50 μg / mL kanamycin sulfate);

[0063] (3) Using the bacterial solution obtained in step (2) as a template, PCR identification was performed using upstream primer L1 and downstream primer R1;

[0064] (4) The bacterial solution identified as positive by PCR in step (3) was sent to Sangon Biotech (Shanghai) Co., Ltd. for sequencing.

[0065] The sequencing result of the TaSNAC11 construction vector is shown in SEQ ID NO: 7. The reference sequence of the TaSNAC11 construction vector is shown in SEQ ID NO: 8. The sequencing result shows that the recombinant expression vector containing the target gene (TaSNAC11), i.e., the recombinant expression vector super1300 (GFP-C)-TaSNAC11, is obtained, and the recombinant expression vector super1300 (GFP-C)-TaSNAC11 is a linearized vector super1300 (GFP-C) to which the TaSNAC11 sequence is added at the XbaI site.

[0066] The plasmid of the bacterial liquid with correct sequencing is extracted and stored at -20°C, and used for subsequent Agrobacterium transformation experiments.

[0067] Example 3: Transformation of Arabidopsis thaliana with the wheat gene TaSNAC11

[0068] 1. Construction of recombinant Agrobacterium

[0069] The recombinant expression vector super1300 (GFP-C)-TaSNAC11 prepared in Example 2 is transformed into competent cells of Agrobacterium tumefaciens GV3101, and the cells are screened and cultured at 28°C in LB solid medium containing 50 μg / mL kanamycin sulfate and 20 μg / mL rifampicin.

[0070] The positive monoclonal cells are picked and cultured at 28°C and 180 rpm for 12 h (the culture medium is LB liquid medium, supplemented with 50 μg / mL kanamycin sulfate and 20 μg / mL rifampicin).

[0071] 1 μL of the bacterial liquid is aspirated, and PCR identification is performed using the upstream primer L1 and the downstream primer R1.

[0072] The bacterial liquid that is positive in PCR identification is the recombinant Agrobacterium tumefaciens containing the recombinant expression vector super1300 (GFP-C)-TaSNAC11, and the recombinant Agrobacterium tumefaciens is named GV3101 / super1300 (GFP-C)-TaSNAC11.

[0073] 2. Obtaining of transgenic Arabidopsis thaliana

[0074] The method for obtaining of transgenic Arabidopsis thaliana is as follows:

[0075] (1) Plant preparation before infection: Wild-type seeds of the Columbia ecotype Arabidopsis thaliana were vernalized at 4°C for 72 h, sown on MS solid culture medium, and cultured in a culture room at 22°C, 15 h light / 9 h dark, and 60%-70% humidity. When the seeds grew to two true leaves, they were transplanted into pots filled with mixed culture medium (nutrient soil and vermiculite mixed in a mass ratio of 3:1). After the plants bloomed, the tops of the main branches were cut off (to promote the development of lateral branches), and sufficient water was applied the day before infection.

[0076] (2) Activation of Agrobacterium: Pour 2 mL of recombinant Agrobacterium tumefaciens GV3101 / super1300 (GFP-C) - TaSNAC11 bacterial solution into a pre-sterilized 250 mL conical flask on a clean bench, add 150 mL of LB liquid medium containing 50 μg / mL kanamycin sulfate and 20 μg / mL rifampicin, and culture in a full-temperature shaker at 28°C for 16 h until the OD 600 When the concentration reaches 0.8, divide the bacterial solution into three 50 mL centrifuge tubes, centrifuge at 5500 g for 20 min, discard the supernatant and keep the bacterial cells;

[0077] (3) Prepare the resuspension: dissolve 2.5 g of sucrose in 50 mL of distilled water, then add 10 μL of silmet-77;

[0078] (4) Add the resuspension solution to the activated Agrobacterium cells in batches, adding 10 mL each time and measuring the OD while adding. 600 Until it reaches 0.8, a resuspended bacterial solution is obtained;

[0079] (5) Infecting Arabidopsis thaliana by floral dipping: At 9:00 a.m. (flowering is most vigorous at this time, which is conducive to infection), use a pipette tip to take 1 mL of the mixed resuspended bacterial solution and drop it on the Arabidopsis inflorescence for infection. After the inflorescence is fully infected, it is immediately placed in the dark for 1 day, and then watered when it is light. A second infection is performed after one week.

[0080] (6) Harvesting seeds of infected Arabidopsis plants: Cultivating the Arabidopsis plants that have been treated with the second infection by conventional methods until they are fruitful, and harvesting mature T0 generation seeds;

[0081] (7) Cultivate T0 generation positive seedlings: Sterilize T0 generation seeds and then evenly spread them on MS solid medium containing 60 μL / 100 mL hygromycin. Cultivate until Arabidopsis seedlings grow true leaves, and some seedlings have healthy true leaves and roots that penetrate the medium for a longer time (about 14 days). Then obtain T0 generation positive seedlings. Move the T0 generation positive seedlings to a planting pot filled with mixed culture medium (nutrient soil and vermiculite mixed in a mass ratio of 3:1) for cultivation. Harvest mature T1 generation seeds from individual plants.

[0082] (8) Cultivate the T1 generation seeds into T1 generation strains with hygromycin resistance according to the method described in step (7). If the ratio of positive seedlings to dead seedlings is approximately 3:1, it is a single copy strain. Then, cultivate the plants in the planting pots by conventional methods until they are fruitful, and harvest the mature T2 generation seeds produced by each plant in the T1 generation strain.

[0083] (9) Ten T2 generation seeds were randomly selected for hygromycin resistance screening using the same method. The strains that no longer showed hygromycin resistance were considered homozygous. Finally, two TaSNAC11 overexpressing T2 generation homozygous strains were obtained.

[0084] (10) Harvest mature T3 seeds of the TaSNAC11 overexpression T2 homozygous strain (i.e., TaSNAC11 overexpression T3 homozygous transgenic Arabidopsis seeds, respectively designated as seeds OE1 and seeds OE2) for the next step of phenotypic identification and analysis.

[0085] The T0 generation represents the seeds produced by the transformed generation and the plants grown from them; the T1 generation represents the seeds produced by self-pollination of the T0 generation and the plants grown from them; the T2 generation represents the seeds produced by self-pollination of the T1 generation and the plants grown from them; the T3 generation represents the seeds produced by self-pollination of the T2 generation and the plants grown from them; a strain represents the seeds or plant group produced by self-pollination of the same plant in the previous generation.

[0086] Example 4: PCR identification of T3 generation homozygous transgenic Arabidopsis

[0087] Seeds OE1 and OE2 obtained in Example 3 were cultured into plants (i.e., TaSNAC11 overexpressing T3 homozygous transgenic lines, denoted as line OE1 and line OE2, respectively) using conventional methods. Leaves of line OE1 and line OE2 were respectively taken, and DNA was extracted from the leaves using the CTAB method. PCR amplification was performed using the upstream primer L1 and the downstream primer R1.

[0088] The results of PCR product electrophoresis are shown in Figure 2 PCR identification results showed that both strains OE1 and OE2 were TaSNAC11 overexpressing strains.

[0089] Example 5: Real-time fluorescence quantitative PCR detection of T3 generation homozygous transgenic Arabidopsis

[0090] Roots of strains OE1 and OE2, as well as a wild-type strain of the Columbia ecotype Arabidopsis thaliana (denoted as WT), were photographed. Total RNA was extracted using Trizol and purified, then reverse-transcribed using HiScript III RT SuperMix for qPCR (with gDNA wiper) to generate cDNA. Real-time fluorescence quantitative PCR was performed using qRT-PCR primers targeting TaSNAC11, using the wheat TaActin gene as an internal reference gene.

[0091] The real-time fluorescence quantitative PCR instrument model is ABI QuantStudio3, using ChamQTMSYBR Color qPCR Master Mix reagents and the expression level of the wheat TaActin gene as an internal reference. The results were analyzed using the comparative threshold method to quantitatively analyze the real-time fluorescence quantitative PCR results. The fluorescence threshold was set and the cycle number Ct value at this fluorescence threshold was determined. The C value was calculated based on the Ct value, C=2 -△Ct , △Ct=Ct 目的基因 -Ct 内参基因 Calculate the average of the three repeated C values ​​as the relative expression level of the target gene

[0092] The reaction system was as follows: 2×ChamQ SYBR Color qPCR Master Mix 5 μL, 50×ROX ReferenceDye II 0.2 μL, upstream primer (10 μM) 0.2 μL, downstream primer (10 μM) 0.2 μL, 3-fold diluted first-strand cDNA solution 0.5 μL, and ddH2O 3.9 μL.

[0093] The qRT-PCR amplification procedure uses a three-step approach:

[0094] (1) Pre-denaturation: 95°C for 3 min;

[0095] (2) Cyclic reaction: 95°C for 15 s, 59°C for 20 s, for a total of 40 cycles;

[0096] (3) Melting curve: 95℃ reaction for 15s, 60℃ reaction for 60s, and 95℃ reaction for 15s.

[0097] The primer sequences used for real-time fluorescence quantitative PCR in this step are as follows:

[0098] Actin-L: 5'-TATGCCAGCGGTCGAACAAC-3' (SEQ ID NO: 9);

[0099] Actin-R: 5'-GGAACAGCACCTCAGGGCAC-3' (SEQ ID NO: 10);

[0100] qRT-L: 5'-GGTTAGCAGTCGAAGTTATCT-3' (SEQ ID NO: 11);

[0101] qRT-R: 5'-TTGCGGAGGTAGTGGAGGAT-3' (SEQ ID NO: 12).

[0102] The qRT-PCR amplification results are shown in Figure 3 .Depend on Figure 3 It can be seen that the expression level of the exogenous gene TaSNAC11 in strains OE1 and OE2 is significantly higher than that in strain WT, that is, the expression level of the exogenous gene TaSNAC11 in transgenic Arabidopsis plants is significantly higher than that in wild-type plants.

[0103] Example 6: Phenotypic Identification of T3 Generation Homozygous Transgenic Arabidopsis Plants

[0104] 1. Phenotypic identification of germination rate of TaSNAC11 overexpressing T3 homozygous transgenic Arabidopsis lines during germination

[0105] ABA stress treatment medium: Add 41.4 g MS solid powder to 1 L distilled water, stir thoroughly, adjust the pH to 6.0, and sterilize at 121°C for 15 min. When the medium cools to 40-50°C, add an appropriate amount of abscisic acid (ABA) to a concentration of 0.5 μM ABA. Mix thoroughly and pour into a round Petri dish to prepare ABA stress treatment medium with a concentration of 0.5 μM ABA (0.5 μM ABA group). The control group (CK group) did not receive ABA.

[0106] Salt stress treatment medium: Add 41.4 g MS solid powder and 8.775 g NaCl to 1 L distilled water, stir thoroughly, adjust the pH to 6.0, and sterilize at 121°C for 15 min. Once the medium cools to 40-50°C, pour it into a round Petri dish to prepare a salt stress treatment medium with a NaCl concentration of 150 mM (150 mM NaCl group). No NaCl was added to the control group (CK group).

[0107] Seeds OE1 and OE2 obtained in Example 3, as well as wild-type seeds of the Columbia ecotype Arabidopsis thaliana (denoted as WT seeds), were plated on an ABA-stress-treated medium containing 0.5 μM ABA or a salt-stress-treated medium containing 150 mM NaCl, and cultured. A control group (CK group) was set up. The germination of seeds in each group was observed, and the germination rate was statistically analyzed after 10 days.

[0108] The germination rate statistics of TaSNAC11 overexpressing T3 homozygous transgenic Arabidopsis seeds OE1 and OE2 and wild-type seeds of Columbia ecotype Arabidopsis thaliana under ABA stress are shown in Figure 4 .Depend on Figure 4 It can be seen that under normal conditions (CK group), the germination rate of seeds OE1 and seeds OE2 had no significant difference compared with the germination rate of seeds WT; under ABA stress (0.5μM ABA group), the germination rate of seeds OE1 and seeds OE2 was significantly reduced by 12.11% and 9.53% respectively compared with the germination rate of seeds WT.

[0109] The statistical results of germination rates of TaSNAC11 overexpressing T3 homozygous transgenic Arabidopsis seeds OE1 and OE2 and wild-type seeds of Columbia ecotype Arabidopsis thaliana under salt stress are shown in Figure 5 .Depend on Figure 5 It can be seen that under normal conditions (CK group), the germination rate of seeds OE1 and seeds OE2 had no significant difference compared with the germination rate of seeds WT; under salt stress (150mM NaCl group), the germination rate of seeds OE1 and seeds OE2 was significantly increased by 39.33% and 32.14% respectively compared with the germination rate of seeds WT.

[0110] The above results indicate that the transgenic lines have higher sensitivity to ABA during seed germination and higher tolerance to salt stress.

[0111] 2. Phenotypic identification of TaSNAC11 overexpressing T3 homozygous transgenic Arabidopsis thaliana lines at the seedling stage

[0112] Square plate salt stress treatment medium: Add 41.4g MS solid powder and 8.775g NaCl to 1L distilled water, stir thoroughly, adjust the pH to 6.0, and sterilize at 121°C for 15 minutes. When the medium cools to 40-50°C, pour the medium (square plate) to prepare a square plate salt stress treatment medium with a NaCl concentration of 150mM (NaCl group). No NaCl was added to the control group (CK group).

[0113] TaSNAC11-overexpressing T3 homozygous transgenic Arabidopsis thaliana lines OE1 and OE2 and the wild-type line WT of the Columbia ecotype Arabidopsis thaliana were cultured in an incubator under normal conditions for 5 days. They were then transferred to salt stress treatment medium supplemented with NaCl for vertical culture (OE1-NaCl group, OE2-NaCl group, WT-NaCl group). Control groups (OE1-CK group, OE2-CK group, WT-CK group) were also set up. After 10 days of culture, photos were taken and the root length of the plants was statistically analyzed.

[0114] The root growth of each strain in the control group is shown in Figure 6 , root length statistics are shown in Figure 7 .Depend on Figure 6 and Figure 7 It can be seen that under normal conditions, there is no significant difference in the root length of strains OE1 and OE2 compared with the root length of strain WT.

[0115] The root growth of each strain in the square plate salt stress group is shown in Figure 8 , root length statistics are shown in Figure 9 .Depend on Figure 8 and Figure 9 It can be seen that under salt stress, the root length of strains OE1 and OE2 were significantly increased by 39.33% and 43.44% respectively compared with the root length of strain WT.

[0116] 3. Phenotypic identification of TaSNAC11 overexpressing T3 homozygous transgenic Arabidopsis lines at the adult stage

[0117] TaSNAC11-overexpressing T3 homozygous transgenic Arabidopsis thaliana lines OE1 and OE2 and the wild-type line WT of the Columbia ecotype were cultured in round Petri dishes under normal conditions for 5 days and then transferred to plastic pots containing a mixed culture medium (nutrient soil and vermiculite mixed in a mass ratio of 3:1) for culture. They were cultured under normal conditions for 12 days and then subjected to NaCl (200 mM) stress treatment (NaCl group) and normal treatment (CK group). The growth of plants in each group was observed and the plant height was measured on the 8th day. The fresh weight, dry weight, relative conductivity, chlorophyll content, and SOD and POD activities of the plants in each group were determined on the 12th day.

[0118] The statistical results of plant height of each group are shown in Figure 10 .Depend on Figure 10 It can be seen that under normal conditions, there was no significant difference in the plant height of strains OE1 and OE2 compared with that of strain WT; under salt stress conditions, the plant height of strains OE1 and OE2 was significantly increased by 17.11% and 46.32% respectively compared with that of strain WT.

[0119] The fresh weight statistics of each group of plants are shown in Figure 11 .Depend on Figure 11 It can be seen that under normal conditions, the fresh weight of strains OE1 and OE2 had no significant difference from that of strain WT; under salt stress conditions, the fresh weight of strains OE1 and OE2 increased significantly by 121.89% and 193.75% respectively compared with that of strain WT.

[0120] The dry weight statistics of each group of plants are shown in Figure 12 .Depend on Figure 12It can be seen that under normal conditions, there was no significant difference in the dry weight of strains OE1 and OE2 compared with the dry weight of strain WT; under salt stress conditions, the dry weight of strains OE1 and OE2 showed an upward trend compared with the dry weight of strain WT, among which the dry weight of strain OE1 increased by 34.78% compared with the dry weight of strain WT, and the dry weight of strain OE2 significantly increased by 78.26% compared with the dry weight of strain WT.

[0121] The measurement results of the three morphological indices of plant height, fresh weight and dry weight showed that the transgenic lines had higher tolerance to salt stress.

[0122] The statistical results of relative conductivity of each group of plants are shown in Figure 13 .Depend on Figure 13 It can be seen that under normal conditions, the relative conductivity of strain OE1 was significantly higher than that of strain WT, and the relative conductivity of strain OE2 had no significant difference from that of strain WT; under salt stress, the relative conductivity of strains OE1 and OE2 were significantly reduced by 18.46% and 23.46% respectively compared with that of strain WT.

[0123] When cells are exposed to salt stress, they are damaged and electrolytes leak out, which in turn affects their vital activities, manifesting as an increase in relative conductivity. The results showed that under salt stress conditions, transgenic strains suffered less damage than wild-type cells, with less electrolyte leakage, indicating greater salt tolerance.

[0124] The statistical results of chlorophyll content of each group of plants are shown in Figure 14 .Depend on Figure 14 It can be seen that under normal conditions, the chlorophyll content of strains OE1 and OE2 had no significant difference compared with strain WT; however, under salt stress conditions, the chlorophyll content of strains OE1 and OE2 was significantly increased by 13.70% and 19.63% respectively compared with strain WT.

[0125] Chlorophyll is an important material basis for plant photosynthesis. Salt stress accelerates the decomposition of chlorophyll and leads to a decrease in the net photosynthetic rate. The higher chlorophyll content in the TaSNAC11 overexpressing T3 generation homozygous transgenic Arabidopsis lines OE1 and OE2 indicates that their photosynthetic inhibition is lower, and they can accumulate more photosynthetic assimilates, which in turn shows that they are less affected by salt stress.

[0126] The results of SOD activity determination of each group of plants are shown in Figure 15 .Depend on Figure 15 It can be seen that under normal conditions, the SOD activities of strains OE1 and OE2 had no significant difference compared with strain WT; however, under salt stress conditions, the SOD activities of strains OE1 and OE2 were significantly increased by 49.64% and 41.00% respectively compared with strain WT.

[0127] The results of POD activity determination of plants in each group are shown in Figure 16 .Depend on Figure 16 It can be seen that under normal conditions, the POD activities of strains OE1 and OE2 were not significantly different from those of strain WT; however, under salt stress conditions, the POD activities of strains OE1 and OE2 were significantly increased by 16.95% and 17.85% respectively compared with those of strain WT.

[0128] SOD and POD are the main components of the enzymatic antioxidant system that scavenges ROS. Under salt stress, the SOD and POD activities of the TaSNAC11 overexpressing T3 homozygous transgenic Arabidopsis lines OE1 and OE2 were significantly higher than those of the wild-type line WT of the Columbia ecotype Arabidopsis, indicating that they have a stronger ability to scavenge ROS and can effectively reduce the level of membrane lipid peroxidation, thereby alleviating the damage of salt stress to plants.

[0129] In summary, transforming the wheat gene TaSNAC11 into the model plant Arabidopsis thaliana can significantly improve the salt tolerance of Arabidopsis thaliana.

[0130] It should be noted that the above embodiments are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. A person skilled in the art would be able to make other variations or modifications based on the above description. It is not possible to enumerate all embodiments here. Any obvious variations or modifications arising from the technical solution of the present invention remain within the scope of protection of the present invention.

Claims

1. Application of wheat gene TaSNAC11 in improving plant salt tolerance, characterized in that: The nucleotide sequence of the wheat gene TaSNAC11 is shown in SEQ ID NO:

2. Overexpression of the gene can improve the plant's tolerance to salt stress. The plant is wheat or Arabidopsis thaliana.

2. The use according to claim 1, characterized in that The application comprises the following steps: (1) PCR amplification and cloning of the wheat gene TaSNAC11; (2) The cloned wheat gene TaSNAC11 was linked into an expression vector to obtain an overexpression recombinant vector; (3) Transforming the overexpression recombinant vector into Agrobacterium to obtain an overexpression recombinant strain; (4) The overexpression recombinant strain was transformed into plants, and the wheat gene TaSNAC11 overexpression strain was screened and obtained.

3. The use according to claim 2, characterized in that The expression vector is super1300 (GFP-C).

4. The use according to claim 2, characterized in that The Agrobacterium is Agrobacterium tumefaciens GV3101.

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