CN-121975818-A - Melilotus officinalis MaWRKY gene and application thereof

Abstract

The invention relates to the field of biotechnology, in particular to a trifolith MaWRKY gene of white flower and application thereof, wherein the trifolith MaWRKY gene of white flower is cloned, the expression mode of the trifolith MaWRKY gene under the condition of salt stress is analyzed by adopting real-time quantitative PCR, and the salt tolerance of yeast cells can be obviously improved by constructing a yeast heterologous expression vector, which proves that MaWRKY. Further constructs the plant over-expression and RNAi vector and converts the trifolith hairy root of the white flower, and the result shows that MaWRKY76,76 not only participates in regulating and controlling the root nodule symbiotic process, but also plays a key role in resisting salt stress. The genetic strategy based on MaWRKY & lt 76 & gt can effectively improve symbiotic nitrogen fixation efficiency, plant sustainability and yield of sweet clover under salt stress, provides a theoretical basis for realizing efficient nodulation and nitrogen fixation of leguminous plants under adversity stress, and has positive significance for promoting green sustainable agricultural development.

Inventors

• ZHANG JIYU
• WANG SHENGSHENG
• Ao Bao
• Qu Yuncan

Assignees

• 兰州大学

Dates

Publication Date

20260505

Application Date

20260212

Claims (9)

1. The MaWRKY76 gene is characterized in that the nucleotide sequence of the MaWRKY gene is shown as SEQ ID NO. 1.
2. The protein coded by the MaWRKY76 gene is characterized in that the amino acid sequence of the protein is shown as SEQ ID NO. 2.
3. 3. An expression vector comprising the coding sequence of MaWRKY76,76 as set forth in claim 1 as set forth in SEQ ID No.1.
4. 4. Use of MaWRKY gene 3836 according to claim 1 to increase salt tolerance, promote plant growth, promote plant root growth and/or promote plant root nodulation of plants, said plants being sweet clover.
5. 5. The use of MaWRKY gene according to claim 1 to increase glutathione reductase activity, superoxide dismutase activity, proline content, glutathione peroxidase activity and reduce malondialdehyde content, hydrogen peroxide content under high salt stress, said plant is trifolitan.
6. 6. The use according to claim 5, wherein the concentration of NaCl in the high salt concentration is 250 mM.
7. 7. Use of MaWRKY gene 3836 according to claim 1 to promote nodulation of root system of plants, i.e. sweet clover, under high salt stress.
8. 8. The use according to claim 5, wherein the concentration of NaCl in the high salt concentration is 75 mM.
9. 9. A method for improving salt tolerance, promoting plant growth, promoting root nodulation, and/or promoting root nodulation under salt stress in sweet clover using the MaWRKY76,76 expression vector of claim 3, comprising: (1) Constructing MaWRKY76 overexpression vector containing the nucleotide sequence according to claim 1; (2) Transforming agrobacterium rhizogenes with the over-expression vector plasmid constructed in the step (1), and infecting hairy roots of the sweet clover with the agrobacterium rhizogenes.

Description

Melilotus officinalis MaWRKY gene and application thereof Technical Field The invention relates to the technical field of biology, in particular to a sweet clover MaWRKY gene and application thereof. Background Leguminous plants and rhizobium are symbiotic to form rhizobium, atmospheric nitrogen can be converted into ammonia, and a nitrogen source is provided for the plants, so that the leguminous plant and rhizobium are important bases for sustainable agriculture. The research in the prior art finds that the symbiotic process of leguminous plants and rhizobia starts from the recognition of signal molecules of both parties and is precisely regulated and controlled by key transcription factors such as NIN and the like. However, it is also demonstrated in the prior art that plants severely inhibit the symbiotic nodulation process under salt stress conditions. The high salt conditions can prevent rhizobia from colonizing and interfere with the formation of infection lines, resulting in reduced nodulation numbers and nitrogen fixation efficiency, ultimately affecting crop yield. Studies have shown that salt stress interferes with nodulation through multiple molecular pathways, where NIN transcription factors play a central hub role in integrating stress signals with developmental programs. WRKY is an important transcription factor widely involved in stress response in plants, and is proved to be capable of enhancing salt tolerance by regulating and controlling mechanisms such as antioxidation, root development and the like in species such as arabidopsis thaliana, corn and the like. However, whether the WRKY transcription factor can promote symbiotic nodulation of leguminous plants is not clear, whether the WRKY transcription factor has influence on NIN transcription factors is not reported, however, a great amount of saline-alkali soil exists in China, if the regulation mechanism can be analyzed, the regulation mechanism is not only helpful for essentially improving the salt tolerance of crops per se, but also provides potential gene regulation targets and new breeding directions for promoting transformation of large-area saline-alkali soil in China from 'improvement adaptation' to 'ecological efficient utilization'. Disclosure of Invention In view of the above, it is necessary to provide MaWRKY gene and application thereof, which can promote salt tolerance of sweet clover, promote plant growth, promote plant root growth, and promote plant root nodulation, especially under salt stress condition. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: MaWRKY76 gene, the nucleotide sequence of MaWRKY gene is shown as SEQ ID NO. 1. The invention also comprises a MaWRKY gene coded protein, and the amino acid sequence of the protein is shown as SEQ ID NO. 2. The invention also comprises an expression vector which contains the coding sequence SEQ ID NO.1 of the MaWRKY gene according to claim 1. The invention also comprises the application of MaWRKY gene in improving the salt tolerance of plants, promoting the growth of plant root systems and/or promoting the nodulation of plant root systems, wherein the plants are sweet clover. The invention also comprises application of MaWRKY gene in improving glutathione reductase activity, superoxide dismutase activity, proline content, glutathione peroxidase activity, reducing malondialdehyde content and hydrogen peroxide content under high salt concentration stress, wherein the plant is sweet clover. Further, the concentration of NaCl in the high-salt concentration is 250 mM. The invention also comprises application of MaWRKY gene in promoting nodulation of plant root system under high salt concentration stress, wherein the plant is trifolith white flower. Further, the concentration of NaCl in the high salt concentration is 75 mM. The invention also comprises a method for improving salt tolerance of sweet clover, promoting plant growth, promoting root nodulation and/or promoting root nodulation under salt stress by applying MaWRKY expression vector, which comprises the following steps: (1) Constructing MaWRKY76 overexpression vector containing the nucleotide sequence according to claim 1; (2) Transforming agrobacterium rhizogenes with the over-expression vector plasmid constructed in the step (1), and infecting hairy roots of the sweet clover with the agrobacterium rhizogenes. The invention has the following beneficial effects: The invention firstly clones the trifoliter MaWRKY gene and adopts real-time quantitative PCR to analyze the expression mode of the trifoliter MaWRKY gene under the condition of salt stress, and confirms that MaWRKY76 can obviously improve the salt tolerance of yeast cells by constructing a yeast heterologous expression vector. Further constructs the plant over-expression and RNAi vector and converts the trifolith hairy root of the white flower, and the result shows that MaWRKY76,76 not only participates in reg