Small peptide hormone for improving high-temperature stress resistance of rice and / or yield of rice under high-temperature stress and application of small peptide hormone

Abstract

The invention discloses a small peptide hormone for improving high temperature stress resistance of rice and / or rice yield under high temperature stress. The amino acid sequence of the small peptide hormone is shown as Seq ID No: 1, and the small peptide hormone is artificially synthesized exogenous spraying small peptide hormone; the invention also discloses a composition containing the small peptide hormone and a preparation method thereof. The invention further discloses a using method and application of the small peptide hormone or the small peptide hormone composition, the small peptide hormone or the small peptide hormone composition is sprayed on the surfaces of rice plant ears, leaves and stalks in a solution form in the flowering period of rice and before high-temperature stress, and the small peptide hormone or the small peptide hormone composition can be applied to improving the high-temperature stress resistance of the rice and / or the rice yield (including the rice maturing rate and the thousand seed weight) under the high-temperature stress. The method can greatly improve the resistance of the rice to high temperature disasters, especially the resistance of the rice to the high temperature disasters in the flowering period, can improve the maturing rate and thousand seed weight of the rice when the high temperature disasters come, can reduce the yield loss caused by high temperature, and has important significance for reducing the high temperature disasters of the rice in summer in China.

Description

Technical Field

[0001] The invention relates to the field of small peptide hormones, in particular to a small peptide hormone for improving the high temperature stress resistance of rice and / or the rice yield under high temperature stress and an application thereof. Background Art

[0002] Rice is a crop of great strategic significance in my country. Rice production is related to the national economy and people's livelihood and my country's food security. In recent decades, my country has experienced frequent high temperatures in summer, which has seriously affected my country's summer rice production. In particular, continuous high temperatures during the flowering period of rice will lead to a decrease in rice fruiting rate and yield, resulting in yield losses. For example, the extreme high temperatures in my country in the summer of 2022 had a huge impact on rice in the middle and lower reaches of the Yangtze River.

[0003] Therefore, in production, there is an urgent need for products and methods that can improve the ability of rice to withstand high temperature stress under high temperature, especially the ability to withstand high temperature stress during the flowering period, and resist high temperature disasters during the flowering period of rice. Currently, there is no report on the use of small peptide hormones to improve the ability of rice to withstand high temperature stress and the rice yield under high temperature stress. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a small peptide hormone for improving the ability of rice to resist high temperature stress and / or the yield of rice under high temperature stress and its application, so that it can greatly improve the resistance of rice to high temperature disasters, especially the resistance to high temperature disasters during the flowering period, increase the rice fruit setting rate and thousand-grain weight when high temperature disasters occur, and reduce the yield loss caused by high temperature.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] In one aspect, the present invention provides a small peptide hormone for improving the ability of rice to resist high temperature stress and / or the yield of rice under high temperature stress, wherein the amino acid sequence of the small peptide hormone is shown in Seq ID No:1.

[0007] As a further improvement of the present invention, the small peptide hormone is an artificially synthesized exogenous sprayable small peptide hormone.

[0008] In a second aspect, the present invention provides a small peptide hormone composition for improving the resistance of rice to high temperature stress and / or the yield of rice under high temperature stress, comprising the above-mentioned small peptide hormone and a solvent for dissolving the small peptide hormone.

[0009] Furthermore, the solvent for dissolving the small peptide hormone is an acetonitrile solvent.

[0010] Furthermore, the small peptide hormone is dissolved in acetonitrile solvent to prepare a solution with a concentration of 10 μM.

[0011] Furthermore, the acetonitrile solvent is a 25% acetonitrile solvent, and the 25% acetonitrile solvent is a solvent prepared by mixing water and acetonitrile in a volume ratio of 3 to 1.

[0012] In a third aspect, the present invention provides a method for preparing the above-mentioned small peptide hormone composition for improving the ability of rice to resist high temperature stress and / or the yield of rice under high temperature stress, comprising the following steps:

[0013] (1) Artificially synthesize the amino acid sequence shown in Seq ID No: 1;

[0014] (2) Dissolving the artificially synthesized amino acid sequence powder in a solvent to prepare a spray solution.

[0015] In a fourth aspect, the present invention provides a method for using the above-mentioned small peptide hormone or small peptide hormone composition, which comprises spraying the small peptide hormone or small peptide hormone composition in the form of a solution on the surface of the panicle, leaves and stems of rice plants during the flowering period of rice and before high temperature stress.

[0016] In a fifth aspect, the present invention provides an application of the above-mentioned small peptide hormone or small peptide hormone composition, wherein the application is to improve the resistance of rice to high temperature stress and / or the rice yield under high temperature stress.

[0017] Furthermore, the application is to perform exogenous spraying in the form of a solution to improve the rice's ability to withstand high temperature stress and / or the rice yield under high temperature stress; improving the rice yield under high temperature stress includes improving the rice fruit setting rate and thousand-grain weight under high temperature stress.

[0018] The present invention has discovered a small peptide hormone through research, which can greatly improve the resistance of rice to high temperature disasters, especially the resistance to high temperature disasters during the flowering period. It can be used to reduce the harm caused by high temperature in summer to rice in my country, increase the rice fruit setting rate and thousand-grain weight when high temperature disasters occur, and reduce the yield loss caused by high temperature. It is of great significance to my country's food security. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0020] Figure 1The graph shows the changes in the fruit set rate of Huazhan and Huazhan GS2 under high temperature treatment; (a) Comparison of the photos of the control (upper) and high temperature treated (lower) Huazhan plants at maturity; (b) Comparison of the photos of the control (upper) and high temperature treated (lower) Huazhan GS2 plants at maturity; (c) Photos of the ears of Huazhan (left) and Huazhan GS2 (right) taken at maturity and treated with normal temperature; (d) Photos of the ears of Huazhan (left) and Huazhan GS2 (right) taken at maturity and treated with high temperature; (e) Comparison of the fruit set rate of Huazhan and Huazhan GS2 under normal temperature (control) and high temperature treatment at maturity;

[0021] Figure 2 This is the expression heat map of 454 genes detected by transcriptome analysis; the left Log2FC_HZHS2_vs_HZCK2 refers to the Log2 Fo ld change value of Huazhan high temperature treatment and Huazhan control, which is obtained by dividing the expression of Huazhan after high temperature treatment by the expression of Huazhan control, and then performing Log2 transformation; the right Log2FC_GS2HS_vs_GS2CK refers to the Log2 Fo ld change value of Huazhan GS2 high temperature treatment and control, which is obtained by dividing the expression of Huazhan GS2 after high temperature treatment by the expression of Huazhan GS2 control, and then performing Log2 transformation;

[0022] Figure 3 This is the expression heat map of 257 proteins detected by proteomic analysis, which were up-regulated in Huazhan after high temperature treatment and down-regulated in Huazhan GS2 after high temperature treatment;

[0023] Figure 4 The figures are a comparison of the fruit set rates of Huazhan and Huazhan GS2 sprayed with small peptide hormones under high temperature; (a) Comparison of photos of mature ears of Huazhan at normal temperature (control), blank group without amino acid sequence spraying under high temperature, and spraying group with amino acid sequence spraying under high temperature; (b) Comparison of photos of mature ears of Huazhan GS2 at normal temperature (control), blank group without amino acid sequence spraying under high temperature, and spraying group with amino acid sequence spraying under high temperature. DETAILED DESCRIPTION

[0024] First of all, it should be pointed out that the present invention was discovered accidentally during the exploration of the heat resistance mechanism of Huazhan and Huazhan GS2. The rice restorer line Huazhan was obtained from the National Crop Germplasm Resource Rice Medium-term Bank of the China National Rice Research Institute. The Huazhan near-isogenic line "Huazhan GS2" is a stable material obtained by multiple continuous self-pollination homozygous from a large-grained single plant selected from the BC4F1 generation through hybridization and 4 backcrossing using Kuangsi Huaju as the donor parent and Huazhan as the recurrent parent. "Huazhan GS2" was provided by the National Rice Improvement Center of the China National Rice Research Institute.

[0025] During the flowering period, Huazhan and Huazhan GS2 were placed in an artificial climate chamber for high temperature treatment. The high temperature treatment method was 7:01 a.m. to 9:34°C; 9:01 a.m. to 14:38°C; 14:01 p.m. to 17:36°C; 17:01 p.m. to 21:33°C at night; 21:01 p.m. to 7:27°C the next morning. After 7 days of high temperature treatment, Huazhan and Huazhan GS2 were transferred to normal temperature conditions for rice growth. The normal temperature adjustment is as follows: 7:01 a.m. to 9:26°C; 9:01 a.m. to 14:30°C; 14:01 p.m. to 17:28°C; 17:01 p.m. to 21:25°C at night; 21:01 p.m. to 7:23°C the next morning. Huazhan and Huazhan GS2 were placed under this normal temperature condition until the rice matured and was harvested. After maturity, the fruiting rate of Huazhan and Huazhan GS2 was investigated. It was found that the fruiting rate of Huazhan after high temperature treatment was 38.3%, while the fruiting rate of Huazhan GS2 after high temperature treatment was 20.7%. Huazhan and Huazhan GS2 were more heat resistant ( Figure 1 ). In order to explore the mechanism by which Huazhan and Huazhan GS2 are more resistant to high temperatures, transcriptome RNA sequencing and proteomic analysis were performed simultaneously on a total of 4 samples, including Huazhan and Huazhan GS2 after high temperature treatment and Huazhan and Huazhan GS2 without high temperature treatment (control) (3 replicates for each sample). It is assumed that the reason why Huazhan and Huazhan GS2 are more heat-resistant is that there are positively regulated heat-resistant genes, that is, the expression level of Huazhan is upregulated after high temperature treatment, while the expression level of Huazhan GS2 is downregulated after high temperature treatment. Based on this hypothesis, in the transcriptome RNA sequencing results, by screening the genes whose expression level was upregulated after high temperature treatment in Huazhan and downregulated after high temperature treatment in Huazhan GS2, a total of 454 related genes were screened out. The gene numbers and Log2 Fo l dchange values ​​of these 454 specific genes are shown in Table 1. That is, the 454 genes listed in Table 1 are likely to be related to the heat tolerance of rice. The heat map of the Log2 Fo ld change values ​​of these 454 genes is shown in Figure 2 .

[0026] In addition, proteomics analysis was used to screen proteins whose expression levels were upregulated after high temperature treatment in Huazhan and whose expression levels were downregulated after high temperature treatment in Huazhan GS2. A total of 257 proteins were screened out. The gene numbers and Log2 Fo ld change values ​​of the coding genes of these 257 specific proteins are shown in Table 2. That is, the 257 protein coding genes listed in Table 2 are likely to be related to rice heat tolerance. The expression heat map of these 257 proteins is shown in Figure 3 .

[0027] By combining transcriptome and proteomics analysis, i.e., comparing the 454 possible heat-resistant related genes detected by transcriptome RNA sequencing listed in Table 1 and the 257 possible heat-resistant protein encoding genes detected by proteome analysis listed in Table 2, it was found that 6 genes were detected together in transcriptome RNA sequencing and proteome analysis, and these 6 common genes are listed in Table 3. The 6 genes listed in Table 3 were used as heat-resistant candidate genes for in-depth analysis. By in-depth analysis of the conserved domains of the proteins encoded by the 6 candidate genes, the amino acid sequences of the conserved domains of the proteins encoded by the 6 genes are shown in Table 4, and by synthesizing the amino acid sequence fragments of the conserved domains of the proteins encoded by the 6 genes listed in Table 4, and applying the 6 amino acid sequence fragments to the leaves of rice plants, and conducting high temperature tests, it was found that the amino acid sequence fragments of the BGIOSGA018627 gene can improve the heat resistance of rice (see Tables 5 and 6 for specific test results), which is why the present invention selects the BGIOSGA018627 gene as a small peptide hormone.

[0028] Table 1. Log2FC values ​​of expression levels of 454 genes detected by transcriptome sequencing (it should be noted that this table only lists some of the 454 genes by way of example)

[0029]

[0030]

[0031]

[0032]

[0033]

[0034] In the above Table 1, the Log2FC_HZHS2_vs_HZCK2 value is greater than 0.5, and the Log2FC_GS2HS2_vs_GS2CK2 is a negative value; Log2FC_HZHS2_vs_HZCK2 refers to the Log2 Fo ld change value of Huazhan high temperature treatment and control, which is obtained by dividing the gene expression level of Huazhan after high temperature treatment by the gene expression level of Huazhan control, and then performing Log2 conversion. A positive value of Log2FC_HZHS2_vs_HZCK2 means that the expression level of the gene increases after high temperature treatment. This table only screens genes with Log2FC_HZHS2_vs_HZCK2 values ​​greater than 0.5, aiming to detect genes with upregulated expression levels in Huazhan after high temperature treatment; Log2FC_GS2HS_vs_GS2CK refers to the Log2 Fo ld change value of Huazhan GS2 high temperature treatment and control. The change value is obtained by dividing the gene expression level of Huazhan GS2 after high temperature treatment by the gene expression level of Huazhan GS2 control, and then performing Log2 transformation. A negative value of Log2FC_GS2HS_vs_GS2CK means that the expression level of the gene decreases after high temperature treatment. This table only screens genes with negative Log2FC_GS2HS_vs_GS2CK values, aiming to detect genes with downregulated expression of Huazhan GS2 after high temperature treatment.

[0035] Table 2 Log2FC values ​​of expression levels of 257 proteins detected by proteomics (It should be noted that this table only lists some of the 257 proteins by way of example)

[0036]

[0037]

[0038]

[0039]

[0040]

[0041] In the above Table 2, the Log2FC_HZHS2_vs_HZCK2 value is greater than 0.2, and the Log2FC_GS2HS2_vs_GS2CK2 is a negative value; Log2FC_HZHS2_vs_HZCK2 refers to the Log2 Fo ld change value of Huazhan high temperature treatment and control, which is obtained by dividing the protein expression level of Huazhan after high temperature treatment by the protein expression level of Huazhan control, and then performing Log2 conversion. A positive value of Log2FC_HZHS2_vs_HZCK2 means that the expression level of the protein increases after high temperature treatment. This table only screens protein-coding genes with Log2FC_HZHS2_vs_HZCK2 values ​​greater than 0.2, aiming to detect proteins whose expression levels in Huazhan are upregulated after high temperature treatment; Log2FC_GS2HS_vs_GS2CK refers to the Log2 Fo ld change value of Huazhan GS2 high temperature treatment and control. The change value is obtained by dividing the protein expression level of Huazhan GS2 after high temperature treatment by the expression level of Huazhan GS2 control protein, and then performing Log2 conversion. A negative value of Log2FC_GS2HS_vs_GS2CK indicates that the expression level of the gene decreases after high temperature treatment. This table only screens protein-coding genes with negative Log2FC_GS2HS_vs_GS2CK values, aiming to detect proteins whose expression levels of Huazhan GS2 are downregulated after high temperature treatment.

[0042] Table 3. Six genes detected by combined transcriptomic and proteomic analysis, i.e. genes that appear in both Table 1 and Table 2

[0043]

[0044]

[0045] Table 4. Amino acid sequences of conserved domains of proteins encoded by six candidate genes obtained by combined transcriptomic and proteomic analysis

[0046]

[0047] The present invention screens tens of thousands of rice genes through transcriptome RNA sequencing and proteomics analysis, screens out 6 candidate genes through joint transcriptome and proteome analysis, synthesizes amino acid sequence fragments of conservative domains of encoded proteins of the 6 candidate genes, and conducts high temperature identification comparison tests after spraying different amino acid sequence fragments, and finally screens out an amino acid sequence fragment (small peptide hormone) that improves the ability of rice to resist high temperature stress and the rice yield under high temperature stress. The process of obtaining the source gene BG IOSGA018627 of the small peptide hormone is shown in the above text description, and the result is an unexpected discovery in the research process, and the specific process of the discovery has been specifically described above.

[0048] The amino acid sequence of the small peptide hormone in the present invention comes from the rice BGIOSGA018627 gene, which is a 58-amino acid sequence intercepted from the full-length 137-amino acid coding sequence of the BGIOSGA018627 gene. The small peptide hormone is obtained by in vitro artificial synthesis.

[0049] The present invention found that exogenous spraying of the amino acid sequence fragment solution can improve the ability of rice to resist high temperature stress, and then conducted experimental verification to further prove the reliability of its application.

[0050] The experimental method of the present invention is as follows:

[0051] Step (1): The 58-length amino acid sequence RRALAARKPTNRYVSYSALDANKVPCNKRGQTYYQNCASQQAANPYRRGCSAI TRCSR was synthesized by Hefei Hesheng Biotechnology Co., Ltd.

[0052] Step (2): dissolving the synthesized 58-length amino acid sequence powder in 25% acetonitrile solvent to prepare a 10 μM concentration solution, wherein the 25% acetonitrile solvent is a solvent prepared by mixing water and acetonitrile in a volume ratio of 3 to 1; wherein the 58-length amino acid sequence powder (i.e., small peptide hormone) is an active substance, and the main function of the acetonitrile solvent is to dissolve the small peptide hormone. It can be understood by those skilled in the art that the purpose of the present invention can also be achieved by using other conventional solvents suitable for plant spraying and capable of dissolving the amino acid sequence powder.

[0053] Step (3): Select the rice restorer line "Hua Zhan" and its near-isogenic line "Hua Zhan GS2" as test materials, and spray the 58-length amino acid sequence solution on the panicle, leaves and stems of Hua Zhan and Hua Zhan GS2 plants 1 hour before the start of high temperature stress during the flowering period of Hua Zhan and Hua Zhan GS2; the purpose is to allow the rice plants including the panicle, leaves and stems to fully absorb the sprayed amino acid sequence for 1 hour. Those skilled in the art can understand that the above-mentioned rice can be different types of rice materials such as indica rice, japonica rice, hybrid rice, conventional rice, sterile line, restorer line, etc. This embodiment only takes Hua Zhan and Hua Zhan GS2 as examples for explanation.

[0054] Step (4): placing Huazhan and Huazhan GS2 in an artificial climate chamber for 7 consecutive days of high temperature treatment, the high temperature treatment method is 7:01 am to 9:34°C; 9:01 am to 14:38°C; 14:01 pm to 17:36°C; 17:01 pm to 21:33°C at night; 21:01 pm to 7:27°C the next morning; the treatment is continuous for 7 days, a total of 168 hours; the purpose of this step is to use the artificial climate chamber to fully simulate the situation of continuous high temperature damage of 38°C for 7 consecutive days encountered in my country's rice-growing areas in summer;

[0055] Step (5): After 7 days of high temperature treatment, Huazhan and Huazhan GS2 are placed in an artificial climate chamber under normal natural temperature conditions until they mature. The purpose of this step is to simulate the situation after 7 days of continuous 38°C high temperature damage in my country's rice-growing areas in summer. Normal natural temperature conditions refer to the following temperature conditions: 7:01 a.m. to 9:26 a.m.; 9:01 a.m. to 14:30 p.m.; 14:01 p.m. to 17:28 p.m.; 17:01 p.m. to 21:25 p.m.; 21:01 p.m. to 7:23 a.m. the next day, and this temperature cycle is repeated every day until the rice matures.

[0056] The above method is described in detail below by way of examples:

[0057] 1. The rice restorer line Huazhan used in this example was obtained from the National Crop Germplasm Resource Rice Mid-term Bank of the China National Rice Research Institute. The Huazhan near-isogenic line "Huazhan GS2" is a stable material obtained by multiple continuous self-pollination homozygous from a large-grained single plant selected from the BC4F1 generation through hybridization and 4 backcrossing using Kuangsi Huaju as the donor parent and Huazhan as the recurrent parent. "Huazhan GS2" was provided by the National Rice Improvement Center of the China National Rice Research Institute. Huazhan and Huazhan GS2 were potted and cultivated. The pot cultivation method was as follows: on May 21, 2024, Huazhan and Huazhan GS2 were sown at the experimental farm of the China National Rice Research Institute in Fuyang District, Hangzhou City, Zhejiang Province. 22 days after sowing, the Huazhan seedlings were transplanted into 12 plastic buckets (the plastic buckets were 20 cm high and 20 cm in diameter), and the Huazhan GS2 seedlings were transplanted into another 12 plastic buckets, with 3 Huazhan or Huazhan GS2 seedlings planted in each plastic bucket, that is, 36 Huazhan single plants were planted in 12 plastic buckets, and 36 Huazhan GS2 single plants were planted in another 12 plastic buckets. Six of the plastic buckets were used for spraying amino acid sequences.

[0058] The solution of RRALAARKPTNRYVSYSALDANKVPCNKRGQTYYQNCASQQAANPYRRGCSAI TRCSR was used for treatment, and 6 plastic buckets were used for treatment without spraying, that is, 6 replicates were used for each treatment. The potting soil was paddy field clay loam, with about 4 kg of dry soil in each bucket, soil organic matter content of 36.1 g / kg, total nitrogen 2.70 g / kg, total phosphorus 0.62 g / kg, total potassium 20.4 g / kg, alkaline nitrogen 239 mg / kg, ammonium nitrogen 9.8 mg / kg, available phosphorus 24.1 mg / kg, available potassium 62 mg / kg, and pH value of 6.5.

[0059] 2. Place the plastic barrels planted with Huazhan or Huazhan GS2 in a ventilated greenhouse with natural normal light and temperature conditions, and manage water and fertilizer normally until Huazhan or Huazhan GS2 heads and blooms.

[0060] 3. Starting from the emergence of the main ear of Huazhan or Huazhan GS2, the ear, leaves and stem surfaces of the plants were treated as follows: (1) spraying 10 μM concentration of amino acid sequence

[0061] The spraying group of RRALAARKPTNRYVSYSALDANKVPCNKRGQTYYQNCASQQAANPYRRGCSAI TRCSR solution had 6 replicates (i.e., spraying Huazhan or Huazhan GS2 planted in 6 plastic buckets, each plastic bucket was a replicate, and each replicate was sprayed with 5 ml); (2) the blank group sprayed with distilled water had 6 replicates (i.e., spraying Huazhan or Huazhan GS2 planted in 6 plastic buckets, each plastic bucket was a replicate, and each replicate was sprayed with 5 ml). One hour after the rice plants were sprayed, 12 plastic buckets planted with Huazhan (6 replicates in the spraying group and 6 replicates in the blank group), and 12 plastic buckets planted with Huazhan GS2 (6 replicates in the spraying group and 6 replicates in the blank group) were placed in an artificial climate chamber for high temperature treatment. The treatment temperature was from 7:01 a.m. to 9:34 a.m.; from 9:01 a.m. to 14:38 p.m.; from 14:01 p.m. to 17:36 p.m.; from 17:01 p.m. to 21:33 p.m.; and from 21:01 p.m. to 7:27 a.m. the next day. The treatment was continuous for 7 days, totaling 168 hours.

[0062] 4. After 7 days of high temperature treatment, set the temperature of the artificial climate chamber to the following temperatures: 7:01 a.m. to 9:26 a.m.; 9:01 a.m. to 14:30 p.m.; 14:01 p.m. to 17:28 p.m.; 17:01 p.m. to 21:25 p.m.; 21:01 p.m. to 7:23 a.m. the next day; and cycle according to this temperature every day until the rice matures.

[0063] 5. After Huazhan or Huazhan GS2 matured and was harvested, all ears were collected and the fruit set rate, thousand-grain weight and yield were measured. As can be seen from Table 5, the fruit set rate of Huazhan in the spraying group sprayed with the amino acid sequence was 50.69%, which was higher than the fruit set rate of 37.92% in the blank group not sprayed with the amino acid sequence. The thousand-grain weight of Huazhan in the spraying group sprayed with the amino acid sequence was 17.72 grams, which was also higher than the thousand-grain weight of 16.95 grams in the blank group not sprayed with the amino acid sequence. The yield per barrel of Huazhan in the spraying group sprayed with the amino acid sequence was 13.52 grams, which was also higher than the 10.41 grams in the blank group not sprayed with the amino acid sequence. As can be seen from Table 6, the fruit set rate of Huazhan GS2 in the spraying group sprayed with the amino acid sequence was 40.26%, which was higher than the fruit set rate of 20.0% in the blank group not sprayed with the amino acid sequence. The 1000-grain weight of Huazhan GS2 in the group sprayed with amino acid sequence was 26.66 grams, which was also higher than the 1000-grain weight of 26.03 grams in the blank group without amino acid sequence spraying. The yield per barrel of Huazhan GS2 in the group sprayed with amino acid sequence was 15.45 grams, which was also higher than the 7.76 grams in the blank group without amino acid sequence spraying. Figure 4 .

[0064] Table 5 Comparison of fruit setting rate, 1000-grain weight and yield of Huazhan treated with two different spraying treatments at flowering stage, high temperature treatment for 7 days, and normal temperature until maturity (6 replicates per treatment).

[0065]

[0066] Table 6 Comparison of the fruit setting rate, 1000-grain weight and yield of Huazhan GS2 treated with two different spraying treatments at the flowering stage, high temperature treatment for 7 days, and normal temperature until maturity (6 replicates per treatment).

[0067]

[0068] In summary, this embodiment simulates the 38°C continuous high temperature disaster encountered in my country's rice-growing areas in summer by subjecting two rice materials, Huazhan and Huazhan GS2, to high temperature treatment in an artificial climate chamber for 7 consecutive days. The experimental results have important practical significance and application value. Spraying the solution of the amino acid sequence RRALAARKPTNRYVSYSALDANKVPCNKRGQTYYQNCASQQAANPYRRGCSAI TRCSR can greatly improve the fruit setting rate, 1000-grain weight and yield of rice plants, which is of great significance for reducing disasters and losses caused by high temperature disasters of rice in summer in my country.

[0069] The above description is merely an embodiment of the application of the present invention to rice materials Huazhan and Huazhan GS2, and does not limit the present invention in any form. Any simple modifications, equivalent changes or modifications to other rice materials made by those skilled in the art using the above-disclosed technical contents shall fall within the protection scope of the present invention.

Claims

1. A small peptide hormone for improving the ability of rice to resist high temperature stress and / or the yield of rice under high temperature stress, characterized in that: The amino acid sequence of the small peptide hormone is shown in Seq ID No:

1.

2. The small peptide hormone for improving the ability of rice to resist high temperature stress and / or the yield of rice under high temperature stress according to claim 1, characterized in that: The small peptide hormone is an artificially synthesized exogenous sprayable small peptide hormone.

3. A small peptide hormone composition for improving the ability of rice to resist high temperature stress and / or the yield of rice under high temperature stress, characterized in that: The invention comprises the small peptide hormone according to claim 1 or 2 and a solvent for dissolving the small peptide hormone.

4. The small peptide hormone composition for improving the ability of rice to resist high temperature stress and / or the yield of rice under high temperature stress according to claim 3, characterized in that: The solvent for dissolving the small peptide hormone is acetonitrile solvent.

5. The small peptide hormone composition for improving the ability of rice to resist high temperature stress and / or the yield of rice under high temperature stress according to claim 4, characterized in that: The small peptide hormone was dissolved in acetonitrile solvent to prepare a solution with a concentration of 10 μM.

6. The small peptide hormone composition for improving the ability of rice to resist high temperature stress and / or the yield of rice under high temperature stress according to claim 5, characterized in that: The acetonitrile solvent is a 25% acetonitrile solvent, and the 25% acetonitrile solvent is a solvent prepared by mixing water and acetonitrile in a volume ratio of 3 to 1.

7. A method for preparing the small peptide hormone composition for improving the ability of rice to resist high temperature stress and / or the yield of rice under high temperature stress according to any one of claims 3 to 6, characterized in that: The steps include: (1) Artificially synthesize the amino acid sequence shown in Seq ID No: 1; (2) Dissolving the artificially synthesized amino acid sequence powder in a solvent to prepare a spray solution.

8. A method for using the small peptide hormone according to claim 1 or 2 or the small peptide hormone composition according to any one of claims 3 to 6, characterized in that: During the rice flowering period and before high temperature stress, spray the solution on the surface of rice plant ears, leaves and stems.

9. Use of the small peptide hormone according to claim 1 or 2 or the small peptide hormone composition according to any one of claims 3 to 6, characterized in that: The application is to improve the rice's ability to resist high temperature stress and / or the rice yield under high temperature stress.

10. The use according to claim 9, characterized in that: The application is to spray the solution exogenously to improve the rice's ability to withstand high temperature stress and / or the rice yield under high temperature stress; Improving the rice yield under high temperature stress includes improving the rice fruit setting rate and thousand-grain weight under high temperature stress.

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