Application of wheat gene TaPSS2 in improving plant drought resistance

Abstract

This invention discloses the application of the wheat gene TaPSS2 in improving plant drought resistance, belonging to the field of functional genomics. The nucleotide sequence of the wheat gene TaPSS2 is shown in SEQ ID NO: 2. Transforming this gene into the model plant Arabidopsis thaliana can significantly improve the drought resistance of Arabidopsis. If the wheat gene TaPSS2 is transformed into wheat, rice, maize, cauliflower, and other plants, it is possible to obtain new germplasm with drought-resistant characteristics, which is of great significance for the breeding of superior crop varieties and their widespread application in production.

Description

Technical Field

[0001] This invention relates to the application of a gene, specifically the application of the wheat gene TaPSS2 in improving plant drought resistance, and belongs to the field of functional genomics technology. Background Technology

[0002] Drought, as an abiotic stress, significantly inhibits crop growth and development. It disrupts a series of physiological and metabolic disorders, including osmotic imbalance, cell dehydration damage, and oxidative damage, leading to hindered seed germination, reduced photosynthetic efficiency, and stagnant growth, ultimately resulting in a sharp decline in yield. Affected by global warming, the scope, frequency, and severity of drought disasters are continuously intensifying. Wheat (Triticum aestivum) is one of my country's major food crops, playing an irreplaceable strategic role in ensuring national food supply and maintaining food security. However, soil drought has become a key bottleneck restricting wheat production in my country, especially in the main wheat-producing areas of the north, where drought stress often leads to significant yield reductions, seriously threatening regional food production stability. Therefore, improving the drought resistance of wheat is an important measure to ensure national food security. Breeding drought-resistant wheat varieties is an effective way to improve wheat drought resistance, and further identifying and discovering key drought-resistant genes is a scientifically sound biotechnological means to cultivate drought-resistant varieties. Summary of the Invention

[0003] This invention screened and cloned the wheat gene TaPSS2 from Chinese spring (CS) wheat and confirmed that the gene can effectively improve the drought resistance of Arabidopsis thaliana.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: Application of wheat gene TaPSS2 in improving plant drought tolerance. The nucleotide sequence of wheat gene TaPSS2 is shown in SEQ ID NO: 2. Overexpression of this gene can improve the plant's tolerance to drought stress. The plant is wheat or Arabidopsis thaliana.

[0005] Preferably, the aforementioned application includes the following steps: (1) PCR amplification and cloning of the wheat gene TaPSS2; (2) The cloned wheat gene TaPSS2 was ligated into an expression vector to obtain an overexpression recombinant vector; (3) The overexpression recombinant vector was transformed into Agrobacterium to obtain the overexpression recombinant strain; (4) Transform the overexpressing recombinant strain into plants, screen and obtain wheat gene TaPSS2 overexpressing lines.

[0006] More preferably, the aforementioned expression vector is super1300 GFP-C; the aforementioned Agrobacterium is Agrobacterium tumefaciens GV3101.

[0007] The advantages of this invention are that transforming the wheat gene TaPSS2 into the model plant Arabidopsis thaliana can significantly improve the drought resistance of Arabidopsis thaliana. If the wheat gene TaPSS2 is transformed into wheat, rice, corn, cauliflower and other plants, it is possible to obtain new germplasm with drought resistance characteristics, which is of great significance for the breeding of superior new crop varieties and the widespread application of superior new crop varieties in production. Attached Figure Description

[0008] Figure 1 This is a schematic diagram of the structure of the target vector super1300 GFP-C; Figure 2 These are PCR identification images of the TapSS2 overexpressing transgenic Arabidopsis thaliana lines (OE1, OE2, OE3); Figure 3 This is a statistical graph showing the relative expression levels of the TaPSS2 gene in the wild-type (WT) Arabidopsis thaliana lines (OE1, OE2, OE3) and the Colombian ecotype Arabidopsis thaliana. Figure 4 This is a statistical chart showing the germination rate of TaPSS2 overexpressing transgenic Arabidopsis seeds (OE1, OE2, OE3) and wild-type Arabidopsis seeds (WT) of the Colombian ecotype Arabidopsis under normal conditions and drought stress treatment. Figure 5 This is a comparison chart of root growth of various strains under normal conditions and drought stress treatment; Figure 6 This is a comparison chart of plant heights of different strains under normal conditions and drought stress treatment; Figure 7 This is a statistical chart of plant height for each line under normal conditions and under drought stress. Figure 8 This is a comparison chart of the growth of various strains under normal conditions and under drought stress. Figure 9 This is a statistical chart of SOD activity of various strains under normal conditions and drought stress treatment; Figure 10 This is a statistical chart of CAT activity of each strain under normal conditions and drought stress treatment; Figure 11 This is a statistical chart of POD activity of each strain under normal conditions and drought stress treatment; Figure 12 This is a statistical chart of APX activity of various lines under normal conditions and drought stress treatment. Detailed Implementation

[0009] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. Unless otherwise specified, the reagents, materials, and instruments used in the embodiments are commercially available. The terminology used in the embodiments generally has the meanings commonly understood by those skilled in the art, unless otherwise stated. Unless otherwise specified, the experimental methods used in the embodiments are conventional methods.

[0010] Example 1: Cloning of the wheat gene TapSS2 Wheat is an important food crop with a wide planting range, and it is also a crop with a strong ability to adapt to harsh external environments. This invention attempts to screen for drought-resistant genes in wheat, and ultimately a drought-resistant gene was screened from Chinese spring (CS) wheat. In the Ensembl Plants database, the gene number of this gene is TraesCS1D02G389300.1. It is located on wheat chromosome 1D, with an ORF (open reading frame) of 1251 bp, an mRNA length of 1668 bp, and a nucleotide sequence as shown in SEQ ID NO: 1. Its encoded product has 416 amino acids, a molecular weight of 48599.48 g / mol, and an isoelectric point of 9.34. This invention names this gene TaPSS2 and clones it using cloning technology. The specific steps are as follows: Total RNA was extracted from leaves of Chinese spring (CS) wheat grown hydroponically for 7 days using the Trizol method. After purification, cDNA was obtained by reverse transcription using HiScript III RT SuperMix for qPCR (+gDNA wiper). Using this cDNA as a template, the TaPSS2 gene was amplified using upstream primer L1 (SEQ ID NO: 3) and downstream primer R1 (SEQ ID NO: 4). The amplified product was sequenced to determine the nucleotide sequence of the target gene.

[0011] The nucleotide sequences of upstream primer L1 and downstream primer R1 are shown below: Upstream primer L1: 5'-ACCGTTTCTCTGTCTCGAGCA-3' (SEQ ID NO: 3); Downstream primer R1: 5'-GAAAAACAGCCCCAGATTTA-3' (SEQ ID NO: 4).

[0012] The PCR reaction system for amplifying the TaPSS2 gene was as follows: 8 μL ddH2O, 12.5 μL 2×Phanta Max Master Mix (DyePlus), 1 μL upstream primer L1, 1 μL downstream primer R1, and 2.5 μL cDNA template.

[0013] The PCR reaction conditions for amplifying the TaPSS2 gene were as follows: 95℃ pre-denaturation for 3 min; 95℃ denaturation for 15 s, 59℃ annealing for 15 s, 72℃ extension for 30 s, repeated for 35 cycles; 72℃ extension for 5 min, and finally stored at 4℃.

[0014] The obtained PCR amplification products were electrophoresed on a 1% agarose gel, and fragments with a sequence length of approximately 1594 bp were recovered. Then, the fragments were subjected to electrophoresis for 5 minutes. TM The TA / Blunt-Zero Cloning Kit was ligated to the pCE2 TA / Blunt-Zero and transformed into E. coli Fast-T1 competent cells. Positive clones were selected for sequencing.

[0015] Sequencing results showed that a DNA fragment with a sequence length of 1594 bp was inserted into the pCE2 TA / Blunt-Zero vector. The nucleotide sequence of this DNA fragment is shown in SEQ ID NO: 2. This sequence contains the gene with gene number TraesCS1D02G389300.1 in the Ensembl Plants database, confirming the presence of the full-length cDNA sequence of the wheat gene TaPSS2.

[0016] Example 2: Construction of recombinant expression vector 1. Amplification of the target gene 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: Upstream primer L2: 5'-atacaccaaatcgactctagaATGGAGGCGGCGGCGGCG-3' (SEQ ID NO: 5); Downstream primer R2: 5'-cataggtacccgggctctagaAAGATTCTTTCTCCGGAATTTCTG-3' (SEQ ID NO: 6).

[0017] The positive Escherichia coli culture containing the pCE2 TA / Blunt-Zero recombinant vector obtained in Example 1 was used as a template for PCR amplification.

[0018] The PCR reaction system consisted of: 8 μL ddH2O, 12.5 μL 2×Phanta Max Master Mix (Dye Plus), 1 μL upstream primer L2, 1 μL downstream primer R2, and 2.5 μL template.

[0019] The PCR reaction program was as follows: 95℃ pre-denaturation for 3 min; 95℃ denaturation for 15 s, 59℃ annealing for 15 s, 72℃ extension for 30 s, repeated for 35 cycles; 72℃ extension for 5 min, and finally stored at 4℃.

[0020] PCR products (target gene) with a sequence length of approximately 1248 bp were recovered for subsequent reactions.

[0021] 2. Carrier linearization Using QuickCut TM XbaI restriction endonuclease was used to linearize and digest the target vector super1300 GFP-C. The specific structure of the target vector super1300 GFP-C is shown in [link to diagram]. Figure 1 A linearized cloning vector was obtained.

[0022] Enzyme digestion system: plasmid 1 μg, 10× QuickCut Green Buffer 2 μL, QuickCut TM Add 1 μL of XbaI and bring the total volume to 20 μL with ddH2O.

[0023] Reaction conditions: 37℃ incubator for 30 minutes.

[0024] 3. Ligation of the target gene and the cloning vector 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-TaPSS2.

[0025] The ligation system is as follows: linearized super1300 GFP-C 3μL, target gene 1μL, 5×CE Ⅱ Buffer 2μL, Exnase Ⅱ 1μL, ddH2O 3μL.

[0026] Reaction conditions: Gently pipette to mix the connection system, briefly centrifuge to collect the liquid at the bottom of the tube, and react at 37°C for 30 min.

[0027] 4. Screening and identification of target gene clones The specific steps for screening and identifying target gene clones are as follows: (1) Take 10 μL of the recombinant reaction product obtained in step 3 and transform it into competent Escherichia coli Fast-T1 cells. Incubate at 37°C upside down for 12 h (the culture medium is LB solid medium with 50 μg / mL kanamycin sulfate added). (2) Pick the single clones obtained in step (1) and culture them at 37℃ and 180rpm for 12h (the culture medium is LB liquid medium with 50μg / mL kanamycin sulfate added). (3) Using the bacterial culture obtained in step (2) as a template, PCR identification was performed using upstream primer L2 and downstream primer R2; (4) The bacterial culture that was positive by PCR in step (3) was sent to Sangon Biotech (Shanghai) Co., Ltd. for sequencing.

[0028] The reference sequence of the TaPSS2 construct vector is shown in SEQ ID NO: 7. The sequencing results of the TaPSS2 construct vector are shown in SEQ ID NO: 8. The sequencing results indicate that this invention yielded a recombinant expression vector containing the target gene TaPSS2, namely the recombinant expression vector super1300 GFP-C-TaPSS2, and that this recombinant expression vector super1300 GFP-C-TaPSS2 is a linearized vector super1300 GFP-C with the TaPSS2 sequence added to the XbaI site.

[0029] Plasmids were extracted from the correctly sequenced bacterial cultures and stored at -20°C for subsequent Agrobacterium-mediated transformation experiments.

[0030] Example 3: Transformation of the wheat gene TaPSS2 into Arabidopsis thaliana 1. Construction of recombinant Agrobacterium The recombinant expression vector super1300 GFP-C-TaPSS2 prepared in Example 2 was transformed into Agrobacterium tumefaciens GV3101 competent cells and screened at 28°C in LB solid medium containing 50 μg / mL kanamycin sulfate and 20 μg / mL rifampin.

[0031] Positive single clones were selected and cultured at 28℃ and 180rpm for 12h (the culture medium was LB liquid medium supplemented with 50μg / mL kanamycin sulfate and 20μg / mL rifampin).

[0032] Take 1 μL of bacterial culture and perform PCR identification using upstream primer L2 and downstream primer R2.

[0033] The bacterial culture that tested positive by PCR was identified as recombinant Agrobacterium tumefaciens containing the recombinant expression vector super1300 GFP-C-TaPSS2. This recombinant Agrobacterium tumefaciens was named GV3101 / super1300 GFP-C-TaPSS2.

[0034] 2. Obtaining transgenic Arabidopsis thaliana The specific methods for obtaining transgenic Arabidopsis thaliana are as follows: (1) Plant preparation before infection: Wild-type seeds of Colombian ecotype Arabidopsis thaliana were vernalized at 4℃ for 72h, sown in MS solid medium, and cultured in a culture room at 22℃, 15h light, 9h darkness and 60%-70% humidity. When the plants grew to two true leaves, they were transplanted into planting pots containing mixed culture medium (nutrient soil and vermiculite mixed in a mass ratio of 3:1). After the plants flowered, the top of the main branch was cut off (to promote the development of lateral branches). Watered thoroughly the day before infection. (2) Activation of Agrobacterium: 2 mL of recombinant Agrobacterium tumefaciens GV3101 / super1300 GFP-C-TaPSS2 bacterial culture was poured into a pre-sterilized 250 mL Erlenmeyer flask in a clean bench. 150 mL of LB liquid medium containing 50 μg / mL kanamycin sulfate and 20 μg / mL rifampin was added. The mixture was incubated in a shaker at 28°C for 16 h until OD was reached. 600 Once the concentration reaches 0.8, the bacterial culture is dispensed into three 50mL centrifuge tubes, centrifuged at 5500g for 20 minutes, the supernatant is discarded, and the bacterial cells are retained. (3) Preparation of resuspension: Dissolve 2.5g of sucrose in 50mL of distilled water, and then add 10μL of silmet-77; (4) Add the resuspension solution to the activated Agrobacterium cells in batches, 10 mL each time, and measure the OD while adding. 600 Continue until the concentration reaches 0.8, at which point a resuspended bacterial solution is obtained; (5) Infecting Arabidopsis thaliana by dipping flowers: At 9:00 a.m. (when the flowers are in full bloom, which is conducive to infection), each time use the tip of a pipette to take 1 mL of the mixed resuspended bacterial solution and drop it onto the Arabidopsis thaliana inflorescence for infection. After all the inflorescences are infected, they are immediately treated in the dark for 1 day. Water is then applied during the light period. A second infection is carried out one week later. (6) Harvest seeds of infected Arabidopsis plants: Arabidopsis plants that have undergone two-stage infection treatment are cultured using conventional methods until they bear fruit, and mature T0 generation seeds are harvested. (7) Cultivation of T0 generation positive seedlings: Disinfect the T0 generation seeds, then evenly spread them on MS solid medium containing 60μL / 100mL hygromycin. Cultivate until Arabidopsis seedlings grow true leaves, and some seedlings grow healthily and have roots that have penetrated the medium for a significantly longer period (about 14 days). T0 generation positive seedlings are obtained. The T0 generation positive seedlings are transferred to planting pots containing mixed culture medium (nutrient soil and vermiculite are mixed in a mass ratio of 3:1) for cultivation. Mature T1 generation seeds are harvested from each plant. (8) Following the method described in step (7), the T1 generation seeds are cultured into T1 generation lines containing hygromycin resistance. If the ratio of positive seedlings to dead seedlings is approximately 3:1, it is a single-copy line. Then, the plants in the planting pots are cultured to fruiting using conventional methods, and the mature T2 generation seeds produced on each individual plant in the T1 generation line are harvested. (9) Ten T2 generation seeds were randomly selected and screened for hygromycin resistance in the same way. The lines that no longer showed hygromycin resistance segregation were homozygous lines. Finally, three TaPSS2 overexpression T2 generation homozygous lines were obtained. (10) Harvest mature T3 generation seeds (referred to as OE1, OE2, and OE3, respectively) of the TapSS2 overexpression T2 generation homozygous lines for further phenotypic identification and analysis.

[0035] T0 generation represents the seeds produced by the transformation of the current generation and the plants that grow from them; T1 generation represents the seeds produced by self-pollination of the T0 generation and the plants that grow from them; T2 generation represents the seeds produced by self-pollination of the T1 generation and the plants that grow from them; T3 generation represents the seeds produced by self-pollination of the T2 generation and the plants that grow from them; lineage represents the population of seeds or plants produced by self-pollination of the same plant from the previous generation.

[0036] Example 4: PCR identification of transgenic Arabidopsis thaliana Leaves from the three TapSS2 overexpressing transgenic Arabidopsis thaliana lines (OE1, OE2, OE3) obtained in Example 3 were taken, and DNA was extracted from the leaves using the CTAB method. PCR amplification was performed using upstream primer L2 and downstream primer R2.

[0037] Electrophoresis results of PCR products are shown below Figure 2 PCR identification results showed that OE1, OE2, and OE3 were all transgenic Arabidopsis lines overexpressing TapSS2.

[0038] Example 5: Real-time quantitative PCR detection of transgenic Arabidopsis thaliana After photographing the root systems of homozygous transgenic lines (OE1, OE2, OE3) and wild-type (WT) Arabidopsis thaliana ecotypes, total RNA was extracted using the Trizol method. The RNA was purified and then reverse transcribed using HiScript III RT SuperMix for qPCR (+gDNA wiper) to obtain cDNA. Using the wheat TaActin gene as an internal reference, real-time quantitative PCR was performed on TaPSS2 using qRT-PCR primers.

[0039] The ABI QuantStudio3 real-time quantitative PCR instrument was used, along with ChamQ™ SYBR Color qPCR Master Mix reagents. The expression level of the wheat TaActin gene was used as an internal control. Results were analyzed using a threshold method to quantify the real-time quantitative PCR results. A fluorescence threshold was set, and the cycle number (Ct) was determined within that threshold. The C value was calculated based on the Ct value, with C=2. -△Ct , △Ct=Ct 目的基因 -Ct 内参基因The average C value of the three replicates was calculated as the relative expression level of the target gene.

[0040] The reaction system consisted of: 5 μL of 2×ChamQ SYBR Color qPCR Master Mix, 0.2 μL of 50×ROX ReferenceDye II, 0.2 μL of upstream primer (10 μM), 0.2 μL of downstream primer (10 μM), 1 μL of first-strand cDNA solution diluted 3 times, and 3.4 μL of ddH2O.

[0041] The qRT-PCR amplification program uses a three-step method: (1) Pre-denaturation: react at 95℃ for 3 min; (2) Cyclic reaction: 95℃ for 15s, 59℃ for 20s, for a total of 40 cycles; (3) Dissolution curves: 95℃ reaction for 15s, 60℃ reaction for 60s, 95℃ reaction for 15s.

[0042] The primer sequences used for real-time quantitative PCR in this step are as follows: Actin-L: 5'-TATGCCAGCGGTCGAACAAC-3' (SEQ ID NO: 9); Actin-R: 5'-GGAACAGCACCTCAGGGCAC-3' (SEQ ID NO: 10); qRT-L: 5'-TGAAAACCTCACGGGAGCC-3' (SEQ ID NO: 11); qRT-R: 5'-GAAAAACAGCCCCAGATTTA-3' (SEQ ID NO: 12).

[0043] The qRT-PCR amplification results are shown below. Figure 3 .Depend on Figure 3 It can be seen that the expression level of the exogenous gene TaPSS2 in transgenic Arabidopsis plants is significantly higher than that in wild-type plants.

[0044] Example 6: Phenotypic identification of transgenic Arabidopsis plants 1. Phenotypic identification of germination rate during germination of TapSS2-overexpressing transgenic Arabidopsis lines Drought stress treatment medium: 39.3g MS solid powder and 54.6g mannitol were added to 1L of distilled water, stirred thoroughly, and the pH was adjusted to 6.0. The medium was then sterilized at 121℃ for 15min. After cooling to 40-50℃, the medium was poured into round petri dishes to prepare a drought stress treatment medium with a mannitol concentration of 300mM (300mM mannitol group). The control group (CK group) did not receive mannitol.

[0045] TaPSS2 overexpressing transgenic Arabidopsis seeds (OE1, OE2, OE3) and wild-type Arabidopsis seeds (WT) were cultured separately on drought stress treatment medium containing 300 mM mannitol. A control group (CK group) was set up, and the germination of seeds in each group was observed. After 8 days, the germination rate was statistically analyzed.

[0046] The germination rates of TapSS2-overexpressing transgenic Arabidopsis seeds (OE1, OE2, OE3) and wild-type Arabidopsis seeds (WT) under mannitol stress are statistically shown in the table below. Figure 4 .Depend on Figure 4 It was found that under normal conditions (CK group), the germination rates of TaPSS2 overexpressing transgenic Arabidopsis seeds OE1, OE2, and OE3 were not significantly different from those of wild-type Arabidopsis seeds WT. Under mannitol stress, the germination rate of TaPSS2 overexpressing transgenic Arabidopsis seeds OE2 was significantly higher than that of wild-type Arabidopsis seeds WT by 18.79%, and OE1 and OE3 also showed an increasing trend, increasing by 10.30% and 12.12%, respectively.

[0047] The above results indicate that the transgenic lines exhibit higher tolerance to drought stress during seed germination.

[0048] 2. Phenotypic identification of TapSS2 overexpressing transgenic Arabidopsis thaliana seedlings Square plate drought stress treatment medium: 39.3g MS solid powder and 54.6g mannitol were added to 1L of distilled water, stirred thoroughly, and the pH was adjusted to 6.0. The medium was then sterilized at 121℃ for 15min. After cooling to 40-50℃, the plates were poured (square plates) to prepare a square plate drought stress treatment medium with a mannitol concentration of 300mM (300mM mannitol group). The control group (CK group) did not receive mannitol.

[0049] TaPSS2 overexpressing transgenic Arabidopsis thaliana lines (OE1, OE2, OE3) and wild-type Arabidopsis thaliana lines (WT) were cultured in an incubator under normal conditions for 12 days. Then, they were transferred to a square plate drought stress treatment medium supplemented with mannitol for vertical culture (OE1-mannitol group, OE2-mannitol group, OE3-mannitol group, WT-mannitol group). A control group (OE1-CK group, OE2-CK group, OE3-CK group, WT-CK group) was set up. After 2 days of culture, the samples were observed and photographed.

[0050] Root growth of each line in the control group and the square plate drought stress group is shown in the figure. Figure 5 .Depend on Figure 5It can be seen that under normal conditions, the root growth of the TaPSS2 overexpressing transgenic Arabidopsis thaliana lines (OE1, OE2, OE3) was not significantly different from that of the wild-type Arabidopsis thaliana line (WT); under drought stress, the root growth of the TaPSS2 overexpressing transgenic Arabidopsis thaliana lines (OE1, OE2, OE3) was better than that of the wild-type Arabidopsis thaliana line (WT).

[0051] 3. Phenotypic identification of adult plants in TapSS2-overexpressing transgenic Arabidopsis thaliana lines The TaPSS2 overexpressing transgenic Arabidopsis thaliana lines (OE1, OE2, OE3) and wild-type Arabidopsis thaliana lines (WT) were cultured in round petri dishes under normal conditions for 8 days. Then, they were transferred to plastic pots containing a mixed culture medium (nutrient soil and vermiculite mixed at a mass ratio of 3:1) and cultured under normal conditions for 15 days. Drought stress treatment (drought stress group) and normal treatment (CK group) were then applied. On day 12, the growth of plants in each group was observed, plant height was measured, and the activity of antioxidant enzymes in each group was determined.

[0052] The comparison of plant height among different lines under normal conditions and drought stress treatment is shown in the figure. Figure 6 The plant height statistics are shown in [link to statistics]. Figure 7 .Depend on Figure 6 and Figure 7 It can be seen that, under normal conditions, the plant height of the TaPSS2 overexpressing transgenic Arabidopsis lines OE1 and OE2 was significantly increased by 18.75% and 39.58% compared with the wild-type Arabidopsis line WT, respectively; under drought stress conditions, the plant height of the TaPSS2 overexpressing transgenic Arabidopsis lines OE1, OE2 and OE3 was significantly increased by 21.76%, 38.14% and 20.29% compared with the wild-type Arabidopsis line WT, respectively.

[0053] The growth comparison of each line under normal conditions and drought stress treatment is shown in the figure. Figure 8 .Depend on Figure 8 It can be seen that under normal conditions, the growth of the TaPSS2 overexpressing transgenic Arabidopsis lines OE1, OE2 and OE3 was not significantly different from that of the wild-type Arabidopsis line WT; under drought stress, the growth of the TaPSS2 overexpressing transgenic Arabidopsis lines OE1, OE2 and OE3 was significantly better than that of the wild-type Arabidopsis line WT.

[0054] The results of SOD activity determination for each strain under normal conditions and drought stress treatment are shown in the figure. Figure 9 .Depend on Figure 9It was found that under normal conditions, the SOD activities of the TaPSS2 overexpressing transgenic Arabidopsis lines OE1, OE2, and OE3 were significantly increased by 32.14%, 31.10%, and 26.97% respectively compared with the wild-type Arabidopsis line WT. Under drought stress, the SOD activities of the TaPSS2 overexpressing transgenic Arabidopsis lines OE1, OE2, and OE3 were significantly increased by 26.86%, 28.01%, and 36.39% respectively compared with the wild-type Arabidopsis line WT.

[0055] The results of CAT activity assays for each strain under normal conditions and drought stress treatment are shown in the figure. Figure 10 .Depend on Figure 10 It can be seen that under normal conditions, the CAT activities of the TaPSS2 overexpressing transgenic Arabidopsis lines OE1, OE2, and OE3 were significantly increased by 95.40%, 88.16%, and 85.01% respectively compared with the wild-type Arabidopsis line WT. Under drought stress, the CAT activities of the TaPSS2 overexpressing transgenic Arabidopsis lines OE1 and OE3 were significantly increased by 31.51% and 35.51% respectively compared with the wild-type Arabidopsis line WT, while the CAT activity of OE2 showed an increasing trend, increasing by 19.64%.

[0056] The results of POD activity assays for each strain under normal conditions and drought stress are shown in the figure. Figure 11 .Depend on Figure 11 It was found that under normal conditions, the POD activity of the TaPSS2 overexpressing transgenic Arabidopsis lines OE1 and OE2 was significantly increased by 26.87% and 19.48% respectively compared with the wild-type Arabidopsis line WT, while there was no significant difference in OE3. Under drought stress, the POD activity of the TaPSS2 overexpressing transgenic Arabidopsis lines OE1, OE2 and OE3 was significantly increased by 13.22%, 15.64% and 11.17% respectively compared with the wild-type Arabidopsis line WT.

[0057] The results of APX activity assays for each strain under normal conditions and drought stress treatment are shown in the figure. Figure 12 .Depend on Figure 12 It can be seen that under normal conditions, the APX activities of the TaPSS2 overexpressing transgenic Arabidopsis lines OE1, OE2, and OE3 were not significantly different from those of the wild-type Arabidopsis line WT. Under drought stress, the APX activities of the TaPSS2 overexpressing transgenic Arabidopsis lines OE2 and OE3 were significantly increased by 71.25% and 39.57% respectively compared with those of the wild-type Arabidopsis line WT, while the APX activity of OE1 showed an increasing trend, increasing by 31.54%.

[0058] Superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and ascorbate peroxidase (APX) are the core components involved in scavenging reactive oxygen species (ROS) induced by stress. Overall, under drought stress, the antioxidant enzyme activities of TaPSS2-overexpressing transgenic Arabidopsis thaliana lines were mostly significantly higher than those of wild-type Arabidopsis thaliana lines. This indicates that TaPSS2-overexpressing transgenic Arabidopsis thaliana lines have a stronger ability to scavenge ROS and can resist ROS damage by inducing increased activity of antioxidant enzymes in the body, thereby enhancing their drought resistance and mitigating the harm of drought stress to the plants.

[0059] In conclusion, transforming the wheat gene TaPSS2 into the model plant Arabidopsis thaliana can significantly improve the drought resistance of Arabidopsis thaliana.

[0060] It should be noted that the above embodiments are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is impossible to exhaustively list all possible implementations here. All obvious variations or modifications derived from the technical solutions of this invention are still within the scope of protection of this invention.

Claims

1. The application of the wheat gene TaPSS2 in improving plant drought tolerance, characterized in that, The nucleotide sequence of the wheat gene TaPSS2 is shown in SEQ ID NO:

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

2. The application according to claim 1, characterized in that, The application includes the following steps: (1) PCR amplification and cloning of the wheat gene TaPSS2; (2) The cloned wheat gene TaPSS2 was ligated into an expression vector to obtain an overexpression recombinant vector; (3) The overexpression recombinant vector was transformed into Agrobacterium to obtain the overexpression recombinant strain; (4) Transform the overexpressing recombinant strain into plants, screen and obtain wheat gene TaPSS2 overexpressing lines.

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

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

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