Rice OsACC gene promoter mutant for resisting ACCase inhibitor herbicides and application of rice OsACC gene promoter mutant

By deleting a portion of the sequence and inserting bases into the promoter of the rice OsACC gene, a rice OsACC gene mutant resistant to ACCase inhibitors was prepared using the CRISPR/Cas12i3 system. This solved the problems of enzyme activity changes and growth and development defects caused by amino acid mutations in existing technologies, achieving resistance to multiple herbicides and ensuring agricultural production safety.

CN121950858APending Publication Date: 2026-05-01INST OF PLANT PROTECTION CHINESE ACAD OF AGRI SCI
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
INST OF PLANT PROTECTION CHINESE ACAD OF AGRI SCI
Filing Date
2026-04-03
Publication Date
2026-05-01

AI Technical Summary

Technical Problem

Existing technologies for breeding ACCase inhibitor-resistant crops result in amino acid mutations that lead to changes in enzyme activity and growth and development defects. Furthermore, frequent use of single herbicides accelerates the evolution of weed resistance and causes phytotoxicity, thus limiting weed control in rice production.

Method used

By deleting a portion of the sequence in the promoter of the rice OsACC gene and inserting a portion of the bases, and using the CRISPR/Cas12i3 system or other gene editing technologies, rice OsACC gene mutants can be prepared to enhance resistance to quizalofop-p-ethyl, haloxyfop-methyl, and clethodim.

Benefits of technology

This study achieved resistance in rice to multiple ACCase inhibitor herbicides, ensuring agricultural production safety, improving herbicide application efficiency, and avoiding growth and development defects.

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Abstract

The invention relates to a rice OsACC gene promoter mutant for resisting ACCase inhibitor herbicides and application of the rice OsACC gene promoter mutant. The rice OsACC gene mutant is a deletion mutant or a deletion and combination insertion mutant; the deletion mutation occurs in the promoter of the rice OsACC gene, and the sequence of the nucleic acid before deletion mutation is as shown in SEQ ID No. 1; the length of the sequence of the deleted nucleic acid is 29 bp to 97 bp, A in the initiation codon ATG of the OsACC gene is 0 site, the deleted nucleic acid occurs in the 305-209 sites of the upstream of the initiation codon ATG, and at least the 271-243 sites of the upstream of the initiation codon ATG are deleted; the inserted nucleic acid occurs within sites 271 to 243 upstream of the initiation codon ATG. The mutant can enable rice to obtain resistance to at least one of herbicides such as haloxyfop-R-methyl, fluazifop-p-butyl and clethodim.
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Description

Technical Field

[0001] This invention relates to the field of nucleic acids, and particularly to a rice herbicide that resists ACCase inhibitors. OsACC Gene promoter mutants and their applications. Background Technology

[0002] Field weeds are one of the major biological hazards in agricultural production, seriously affecting the high-quality development of the rice industry. In weed control strategies, the combined use of chemical control and herbicide-resistant varieties has shown excellent performance. Acetyl-CoA carboxylase (ACCase) inhibitor herbicides are mainly used to control gramineous weeds, and are characterized by high efficiency, low toxicity, and safety for subsequent crops.

[0003] Currently, the development of herbicide-resistant crops using ACCase inhibitors primarily relies on gene editing and other technologies to mutate the coding region of the target protein ACC, resulting in amino acid mutations. These mutations reduce the target protein's binding capacity to herbicides, thus preventing disruption to normal plant life processes and fostering herbicide resistance. However, such protein mutations often alter the enzyme activity of ACC itself, causing growth and developmental defects, which limits its application in production. Furthermore, frequent use of a single herbicide accelerates the evolution of weed resistance and can lead to phytotoxicity. These problems significantly restrict weed control in rice production. Summary of the Invention

[0004] One of the present inventions provides a rice OsACC Gene mutant, the rice OsACC The gene mutant is a deletion mutant; among them, the deletion mutation occurs in rice. OsACC In the gene promoter, the sequence of the nucleic acid before deletion mutation is shown in SEQ ID No. 1; the length of the deleted nucleic acid sequence ranges from 29 bp to 97 bp, among which, OsACC The A in the start codon ATG is at position 0. The deleted nucleic acid occurs at positions 305 to 209 upstream of the start codon ATG (its sequence is shown in SEQ ID No. 11), and at least positions 271 to 243 upstream of the start codon ATG are deleted (its sequence is shown in SEQ ID No. 12). That is, the longest deletion sequence can be SEQ ID No. 11 containing SEQ ID No. 12; it can be any segment of SEQ ID No. 11 containing SEQ ID No. 12; or it can be a combination of any segment of SEQ ID No. 11 containing SEQ ID No. 12 and other sequences of any length in SEQ ID No. 11.

[0005] In one specific implementation, the length of the deleted nucleic acid sequence is between 29 bp and 87 bp, wherein... OsACC The A in the gene start codon ATG is at position 0. The deleted nucleic acid occurs at positions 305 to 219 upstream of the start codon ATG, and at least the bases located at positions 271 to 243 upstream of the start codon ATG are deleted.

[0006] In one specific implementation, the length of the deleted nucleic acid sequence is between 29 bp and 74 bp, wherein... OsACC The A in the gene start codon ATG is at position 0. The deleted nucleic acid occurs at positions 305 to 232 upstream of the start codon ATG, and at least the bases located at positions 271 to 243 upstream of the start codon ATG are deleted.

[0007] In one specific implementation, the length of the deleted nucleic acid sequence is between 29 bp and 92 bp, wherein... OsACC The A in the gene start codon ATG is at position 0. The deleted nucleic acid occurs within positions 300 to 209 upstream of the start codon ATG, and at least positions 271 to 243 upstream of the start codon ATG are deleted.

[0008] In one specific implementation, the length of the deleted nucleic acid sequence is between 29 bp and 82 bp, wherein... OsACC The A in the gene start codon ATG is at position 0. The deleted nucleic acid occurs within positions 300 to 219 upstream of the start codon ATG, and at least the bases located at positions 271 to 243 upstream of the start codon ATG are deleted.

[0009] In one specific implementation, the length of the deleted nucleic acid sequence is between 29 bp and 69 bp, wherein... OsACC The A in the gene start codon ATG is at position 0. The deleted nucleic acid occurs within positions 300 to 232 upstream of the start codon ATG, and at least positions 271 to 243 upstream of the start codon ATG are deleted.

[0010] In one specific implementation, the length of the deleted nucleic acid sequence is 29 bp, and... OsACC The A in the gene start codon ATG is at position 0, and the deleted nucleic acid occurs at positions 271 to 243 upstream of the start codon ATG.

[0011] In one specific implementation, the length of the deleted nucleic acid sequence is 45 bp, and... OsACCThe A in the gene start codon ATG is at position 0, and the deleted nucleic acid occurs at positions 281 to 237 upstream of the start codon ATG.

[0012] In one specific implementation, the length of the deleted nucleic acid sequence is 69 bp, and... OsACC The A in the gene start codon ATG is at position 0, and the deleted nucleic acid occurs at positions 300 to 232 upstream of the start codon ATG.

[0013] The second invention provides a rice OsACC Gene mutant, the rice OsACC Gene mutants are deletion-merged insertion mutants, where deletion-merged insertion mutations occur in rice. OsACC In the gene promoter, the sequence of the deleted and inserted nucleic acid before the mutation is shown in SEQ ID No. 1; the length of the deleted nucleic acid sequence is 29 bp to 97 bp, and the length of the inserted nucleic acid sequence is 1 bp; OsACC The A in the start codon ATG is at position 0. The deleted nucleic acid occurs within positions 305 to 209 upstream of the start codon ATG, and at least positions 271 to 243 upstream of the start codon ATG are deleted. OsACC The A in the gene start codon ATG is at position 0, and the inserted nucleic acid occurs at positions 271 to 243 upstream of the start codon ATG.

[0014] In one specific implementation, the length of the deleted nucleic acid sequence is 29 bp to 87 bp, and the length of the inserted nucleic acid sequence is 1 bp; wherein, with OsACC The A in the start codon ATG is at position 0. The deleted nucleic acid occurs within positions 305 to 219 upstream of the start codon ATG, and at least positions 271 to 243 upstream of the start codon ATG are deleted. OsACC The A in the gene start codon ATG is at position 0, and the inserted nucleic acid occurs at positions 271 to 243 upstream of the start codon ATG.

[0015] In one specific implementation, the length of the deleted nucleic acid sequence is 29 bp to 74 bp, and the length of the inserted nucleic acid sequence is 1 bp; wherein, with OsACC The A in the start codon ATG is at position 0. The deleted nucleic acid occurs within positions 305 to 232 upstream of the start codon ATG, and at least positions 271 to 243 upstream of the start codon ATG are deleted. OsACC The A in the gene start codon ATG is at position 0, and the inserted nucleic acid occurs at positions 271 to 243 upstream of the start codon ATG.

[0016] In one specific implementation, the length of the deleted nucleic acid sequence is 29 bp to 92 bp, and the length of the inserted nucleic acid sequence is 1 bp; wherein, with OsACC The A in the gene start codon ATG is at position 0. The deleted nucleic acid occurs within positions 300 to 209 upstream of the start codon ATG, and at least positions 271 to 243 upstream of the start codon ATG are deleted. OsACC The A in the gene start codon ATG is at position 0, and the inserted nucleic acid occurs at positions 271 to 243 upstream of the start codon ATG.

[0017] In one specific implementation, the length of the deleted nucleic acid sequence is 29 bp to 82 bp, and the length of the inserted nucleic acid sequence is 1 bp; wherein, with OsACC The A in the start codon ATG is at position 0. The deleted nucleic acid occurs within positions 300 to 219 upstream of the start codon ATG, and at least positions 271 to 243 upstream of the start codon ATG are deleted. OsACC The A in the gene start codon ATG is at position 0, and the inserted nucleic acid occurs at positions 271 to 243 upstream of the start codon ATG.

[0018] In one specific implementation, the length of the deleted nucleic acid sequence is 29 bp to 69 bp, and the length of the inserted nucleic acid sequence is 1 bp; wherein, with OsACC The A in the gene start codon ATG is at position 0. The deleted nucleic acid occurs within positions 300 to 232 upstream of the start codon ATG, and at least positions 271 to 243 upstream of the start codon ATG are deleted. OsACC The A in the gene start codon ATG is at position 0, and the inserted nucleic acid occurs at positions 271 to 243 upstream of the start codon ATG.

[0019] In one specific implementation, the length of the deleted nucleic acid sequence is 45 bp to 87 bp, and the length of the inserted nucleic acid sequence is 1 bp; wherein, with OsACC The A in the start codon ATG is at position 0. The deleted nucleic acid occurs within positions 305 to 219 upstream of the start codon ATG, and at least positions 281 to 237 upstream of the start codon ATG are deleted. OsACC The A in the gene start codon ATG is at position 0, and the inserted nucleic acid occurs at positions 281 to 237 upstream of the start codon ATG.

[0020] In one specific implementation, the length of the deleted nucleic acid sequence is 45 bp to 74 bp, and the length of the inserted nucleic acid sequence is 1 bp; wherein, with OsACCThe A in the start codon ATG is at position 0. The deleted nucleic acid occurs within positions 305 to 232 upstream of the start codon ATG, and at least positions 281 to 237 upstream of the start codon ATG are deleted. OsACC The A in the gene start codon ATG is at position 0, and the inserted nucleic acid occurs at positions 281 to 237 upstream of the start codon ATG.

[0021] In one specific implementation, the length of the deleted nucleic acid sequence is 45 bp to 92 bp, and the length of the inserted nucleic acid sequence is 1 bp; wherein, with OsACC The A in the start codon ATG is at position 0. The deleted nucleic acid occurs within positions 300 to 209 upstream of the start codon ATG, and at least positions 281 to 237 upstream of the start codon ATG are deleted. OsACC The A in the gene start codon ATG is at position 0, and the inserted nucleic acid occurs at positions 281 to 237 upstream of the start codon ATG.

[0022] In one specific implementation, the length of the deleted nucleic acid sequence is 45 bp to 82 bp, and the length of the inserted nucleic acid sequence is 1 bp; wherein, with OsACC The A in the gene start codon ATG is at position 0. The deleted nucleic acid occurs within positions 300 to 219 upstream of the start codon ATG, and at least positions 281 to 237 upstream of the start codon ATG are deleted. OsACC The A in the gene start codon ATG is at position 0, and the inserted nucleic acid occurs at positions 281 to 237 upstream of the start codon ATG.

[0023] In one specific implementation, the length of the deleted nucleic acid sequence is 45 bp to 69 bp, and the length of the inserted nucleic acid sequence is 1 bp; wherein, with OsACC The A in the start codon ATG is at position 0. The deleted nucleic acid occurs within positions 300 to 232 upstream of the start codon ATG, and at least positions 281 to 237 upstream of the start codon ATG are deleted. OsACC The A in the gene start codon ATG is at position 0, and the inserted nucleic acid occurs at positions 281 to 237 upstream of the start codon ATG.

[0024] In one specific implementation, the sequence of the nucleic acid to be inserted is C.

[0025] In one specific implementation, the length of the deleted nucleic acid sequence is 45 bp, and the length of the inserted nucleic acid sequence is 1 bp; wherein, with OsACCThe A in the gene start codon ATG is at position 0, and the deleted nucleic acid occurs at positions 281 to 237 upstream of the start codon ATG; OsACC The A in the gene start codon ATG is at position 0, and the inserted nucleic acid occurs at positions 281 to 237 upstream of the start codon ATG.

[0026] The third invention provides rice according to any one of the first or second inventions. OsACC The application of gene mutants in rice ACCase inhibitor herbicides, wherein the rice variety is Nanjing 46 or Nipponbare.

[0027] In one specific embodiment, the ACCase inhibitor herbicide is at least one of quizalofop-P-ethyl, haloxyfop-P-ethyl, and clethodim.

[0028] The fourth invention provides a method for enabling rice to acquire resistance to ACCase inhibitor herbicides, which involves deleting certain components from the rice genome through gene editing or homologous recombination. OsACC A subset of bases in the gene promoter, and optionally directed towards the... OsACC A portion of bases is inserted into the gene promoter to obtain rice as described in any one of the present inventions or the second invention. OsACC The rice variety is Nanjing 46 or Nipponbare, which is achieved through gene mutants.

[0029] In one specific embodiment, the method includes the following steps: 1) Obtain the pHZLib-Cas12i3 vector, or the pHZ33 and pUbi-IEE-Cas12i3 vector; wherein, the pHZLib-Cas12i3 vector is constructed by the following operation: replacing the DR-crRNA-BsaI-BsaI-DR element in pHZ33 with the suicide gene ccdB to obtain the pHZ33-ccdB vector; integrating pHZ33-ccdB with pUbi-IEE-Cas12i3 into a vector to obtain the pHZLib-Cas12i3 vector; 2) Obtain a crRNA sequence or target sequence for gene editing, wherein the crRNA sequence is as shown in SEQ ID Nos. 6 or 8; and the target sequence is located at positions 34 to 56 of the sequence shown in SEQ ID Nos. 6 or 8. 3) Replace the ccdB gene on the pHZLib-Cas12i3 vector with the crRNA, thereby cloning the crRNA sequence into the pHZLib-Cas12i3 vector to obtain pHZLib-Cas12i3-OsACCcrRNA; or clone the target sequence into the pHZ33 vector to obtain the pHZ33-OsACCSpacer vector, and then integrate the pHZ33-OsACCSpacer with the pUbi-IEE-Cas12i3 vector into a single vector to obtain pUbi-IEE-Cas12i3-HZ33-OsACCSpacer; 4) pHZLib-Cas12i3-OsACCcrRNA or pUbi-IEE-Cas12i3-HZ33-OsACCSpacer were transformed into Agrobacterium and infected rice callus tissue to screen for rice lines resistant to ACCase inhibitor herbicides.

[0030] In one specific embodiment, the ACCase inhibitor herbicide is at least one of quizalofop-P-ethyl, haloxyfop-P-ethyl, and clethodim.

[0031] Beneficial effects of the present invention: The present invention discovers that by deleting rice OsACC A portion of the sequence in the promoter of a gene, and optionally directed to... OsACC Inserting a partial base into the gene promoter can confer resistance in rice to at least one of three herbicides: quizalofop-P-ethyl, haloxyfop-R-methyl, and clethodim. This is of great value in ensuring agricultural production safety and improving herbicide application efficiency. Mutants can be generated using the CRISPR / Cas12i3 system, or through other CRISPR / Cas systems, gene editing, or homologous recombination. Attached Figure Description

[0032] Figure 1 For rice OsACC A schematic diagram of the target sites for the non-coding region regulatory elements.

[0033] Figure 2 A schematic diagram of the main components of the knockout vector pHZLib-Cas12i3 and the editing vector library pHZLib-Cas12i3-OsACCcrRNA after inserting crRNA into the CRISPR / Cas12i3 system.

[0034] Figure 3 Sanger sequencing was used to identify allelic variation types and the resistance phenotype of T1 generation plants to quizalofop-p-ethyl by screening resistant plants A3-#13 and A3-#16.

[0035] Figure 4 Sanger sequencing was used to identify allelic variant types and the resistance phenotype of the T1 generation plants to high-efficiency flupyradifurone in the screened resistant plant A3-#17.

[0036] Figure 5 Sanger sequencing was used to identify allelic variation types and the resistance phenotype of T1 generation plants to clethodim in the screened resistant plants A3-#7.

[0037] Figure 6 The resistance phenotypes of A3-#13, A3-#16 and A3-#7 T1 generation plants after spraying with quizalofop-P-ethyl and clethodim.

[0038] Figure 7 The resistance phenotypes of A3-#17 T1 generation plants after spraying with quizalofop-P-ethyl, haloxyfop-P-ethyl, and clethodim.

[0039] Figure 8 The locations where mutations occur in A3-#7, A3-#13, A3-#16, and A3-#17 in the sequence shown in SEQ ID No. 1 are displayed. Detailed Implementation

[0040] The present invention will be further described in detail below through preferred embodiments, but these embodiments do not constitute a limitation thereof.

[0041] Unless otherwise specified, the plasmids and reagents used in the embodiments of this invention can be purchased commercially.

[0042] For details on the pHZLib-Cas12i3 plasmid, please refer to CN202511501754.X.

[0043] All synthesized nucleic acids were outsourced to Beijing Qingke Xinyue Biotechnology Co., Ltd.

[0044] Example 1: Rice OsACC Construction of gene plasmid libraries.

[0045] Reference rice ( Oryza sativa L) Genome Database OsACC The gene sequence (accession number LOC_Os05g22940, rice variety Nipponbare) was amplified and sequenced using the extracted genome of Nanjing 46 as a template to obtain the Nanjing 46 gene sequence. OsACC The gene and its upstream and downstream nucleic acid sequences indicate that Nanjing 46 OsACC The gene and its upstream and downstream nucleic acid sequences are similar to those of Nipponbare. OsACC The gene and its upstream and downstream nucleic acid sequences are completely identical, among which, OsACC The intron and exon sequence length of the gene is 13489. (Japonica rice 46) OsACCThe gene start codon and its upstream nucleic acid sequence are shown in SEQ ID No. 1, where the bases from positions 1 to 1967 from the 5' to 3' ends are... OsACC In the promoter section, bits 1968 to 1970 are the start codon ATG.

[0046] for OsACC The gene editing library for the non-coding region (promoter) of the gene is divided into three libraries (Pool01 covers bases 1 to 610 of the sequence shown in SEQ ID No. 1, Pool02 covers bases 611 to 1214, and Pool03 covers bases 1215 to 1967). Each library contains 20 to 25 crRNA sequences (including conserved repetitive sequences in the CRISPR / Cas12i3 system guide RNA located at both ends of the target sequence, and further sequences flanking the conserved repetitive sequences to facilitate PCR amplification), for a total of 70 sequences. A schematic diagram showing the location of the target sequence in the sequence shown in SEQ ID No. 1 is provided below. Figure 1 .

[0047] Using an equal volume and concentration of a mixture of all crRNA oligonucleotide sequences from each library as templates, and using Array-F (as shown in SEQ ID No. 2) and Array-R (as shown in SEQ ID No. 3) as primers, PCR amplification was performed using I-5™ 2×High-Fidelity Master Mix. The PCR products were recovered to obtain the results for each library. OsACC crRNA of the gene. For the vector pHZLib-Cas12i3... Bsa I enzyme digestion yielded approximately 15.8 kb of the vector backbone (releasing the ccdB gene fragment). The fragments were then processed using 2×MultiF Seamless Assembly Mix to separate the contents of each library. OsACC The crRNA of the gene was cloned into a 15.8 kb vector backbone (that is, the ccdB gene in the pHZLib-Cas12i3 vector was replaced with the ccdB gene in each library). OsACC The crRNAs of the gene were named pHZLib-Cas12i3-OsACCcrRNA(Pool01), pHZLib-Cas12i3-OsACCcrRNA(Pool02), and pHZLib-Cas12i3-OsACCcrRNA(Pool03) respectively. A schematic diagram of the main elements in their plasmids is shown below. Figure 2 As shown in the figure, 40 colonies were randomly selected from each library for sequencing, with an accuracy rate of 98%.

[0048] Example 2: Rice transformation of plasmid library and screening for resistance to ACCase inhibitor herbicides.

[0049] 1) Rice callus induction: hulled mature Nanjing 46 rice seeds were treated with 50% commercial disinfectant for 30 minutes; washed 3 to 5 times with sterile water, then transferred to sterile petri dishes to remove excess water; seeds were placed on MSD plates (4.43 g / L MS powder (Murashige and Skoog medium); 30 g / L sucrose; 2 ml / L 2,4-dichlorophenoxyacetic acid (2,4-D); 8 g / L agar powder; pH 5.7) and cultured in a light-controlled environment for 10 days to induce callus formation; the embryo and bud of the seeds were removed, and the callus tissue was transferred to a new MSD petri dish and cultured for 4 days until it was ready for Agrobacterium transformation.

[0050] 2) Agrobacterium transformation: Three plasmid libraries, pHZLib-Cas12i3-OsACCcrRNA(Pool01) to pHZLib-Cas12i3-OsACCcrRNA(Pool03), were transformed into Agrobacterium strain EHA105 using electroporation, constructing three EHA105 strain libraries containing all the above crRNA plasmid libraries. The three Agrobacterium libraries were then eluted with sterile water and subjected to OD245-distillation. 600 Between steps 1 and 2, Agrobacterium was collected from each bacterial cell bank by centrifugation, resuspended in MSD solution, and its OD value was adjusted. 600 =0.2, to obtain the bacterial suspension for each bacterial cell.

[0051] 3) Agrobacterium infection of rice callus: Place the callus tissue in the suspension of each of the above three bacterial banks for 30 minutes; remove the suspension, transfer the callus tissue to sterile absorbent paper to remove excess suspension, and then transfer the callus tissue to a new MSD medium containing 100 μmol / L acetylsyl syringone and incubate at room temperature in the dark for 2 to 3 days.

[0052] 4) Screening for resistant rice callus: After dark culture, callus tissue was transferred to MSD medium (100 mg / L termethin; 50 mg / L hygromycin B) and cultured for 2 weeks to 2 months until resistant callus appeared on the surface of the callus tissue. The medium was changed every 2 weeks.

[0053] 5) Screening of rice ACCase inhibitor-resistant callus and acquisition of regenerated plants: Resistant callus tissue was transferred to regeneration medium (4.43 g / L MS powder; 30 g / L sucrose; 25 g / L sorbitol; 0.5 mg / L 1-naphthaleneacetic acid (NAA); 3 mg / L 6-benzylaminopurine (6-BA); 100 mg / L termethin; 50 mg / L hygromycin B; 12 g / L agar powder; pH=5.7). After 7 to 10 days, the callus was transferred to regeneration medium containing 5 μmol / L quizalofop-P-ethyl, 1 μmol / L haloxyfop-P-ethyl, and 0.8 μmol / L clethodim, respectively, to screen for rice callus tissue resistant to the corresponding herbicides. The callus was then transferred every 7 to 10 days until seedlings were formed. Seedlings were then transferred to 1 / 2 MS medium (2.21 g / L MS powder). Rooting was achieved using MS powder; 15 g / L sucrose; 8 g / L agar powder; pH 5.7. After screening, five T0 generation rice regenerated plants resistant to quizalofop-P-ethyl (A2-#1, A3-#3, A3-#13, A3-#16, and A3-#20) were obtained; two T0 generation rice regenerated plants resistant to quizalofop-P-ethyl (A3-#1 and A3-#17) were obtained; and one T0 generation rice regenerated plant resistant to clethodim (A3-#7) was obtained. These eight resistant T0 generation rice plants were grown in a greenhouse until self-pollination and T0 generation seeds were harvested.

[0054] 6) Screening of T1 generation ACCase inhibitor-resistant rice.

[0055] 6-1) Screening of T1 generation resistant quizalofop-P-ethyl rice: Seeds from A3-#13 and A3-#16 T0 generation plants and wild-type control were treated with 50% commercial disinfectant for 30 minutes; washed 3 to 5 times with sterile water, and then sown on 1 / 2 MS medium containing 0.8 μmol / L quizalofop-P-ethyl for screening of quizalofop-P-ethyl resistant T1 generation mutant lines. The plants were cultured in a light-controlled incubator for 10 days, and seed germination and plant development were observed. Results are shown in […]. Figure 3 The results showed that wild-type materials germinated but failed to grow on 1 / 2 MS medium containing 0.8 μmol / L quizalofop-P-ethyl, while seeds of A3-#13 and A3-#16 not only germinated on 1 / 2 MS medium containing 0.8 μmol / L quizalofop-P-ethyl, but all of them grew into plants. This indicates that A3-#13 and A3-#16 obtained through screening possess quizalofop-P-ethyl resistance.

[0056] 6-2) Screening of T1 generation rice resistant to high-efficiency flupyradifurone: The difference from 6-1) is that the seeds used were from A3-#17T0 generation plants and a wild-type control. The medium was 1 / 2 MS containing 0.3 μmol / L of high-efficiency flupyradifurone. The plants were cultured in a light-controlled environment for 10 days, and seed germination and plant development were observed. Results are shown below. Figure 4 The results showed that wild-type materials could germinate but not grow on 1 / 2 MS medium containing 0.3 μmol / L haloxyfop-R-methyl, while seeds of A3-#17 could not only germinate but also grow into plants on 1 / 2 MS medium containing 0.3 μmol / L haloxyfop-R-methyl. This indicates that A3-#17 obtained through screening possesses resistance to haloxyfop-R-methyl.

[0057] 6-3) Screening of T1 generation clethodim-resistant rice: The difference from 6-1) is that the seeds were from A3-#7 T0 generation plants and a wild-type control. The medium was 1 / 2 MS containing 0.5 μmol / L clethodim. The plants were cultured in a light-controlled chamber for 10 days, and seed germination and plant development were observed. Results are shown below. Figure 5 The results showed that wild-type materials could germinate but not grow on 1 / 2 MS medium containing 0.5 μmol / L clethodim, while seeds of A3-#7 could not only germinate but also grow into plants on 1 / 2 MS medium containing 0.5 μmol / L clethodim. This indicates that A3-#7 obtained through screening possesses clethodim resistance.

[0058] Example 3: Rice with ACCase inhibitor herbicides OsACC Molecular identification of mutants.

[0059] 1) Genomic DNA Extraction: During the growth period of T0 and T1 generation rice plants, approximately 0.1 g of leaves from resistant T0 and T1 generation plants were harvested, flash-frozen in liquid nitrogen, and then ground using a grinder. 600 μL of 2× cetyltrimethylammonium bromide (CTAB) DNA extraction buffer (containing 1 / 1000 β-mercaptoethanol) was added, and the mixture was vortexed and lysed at 65°C for 45 min. 500 μL of chloroform was added, and the mixture was vigorously shaken to form an emulsion. The emulsion was centrifuged at 14000 rpm for 10 min. After centrifugation, the supernatant was transferred to a 1.5 ml centrifuge tube, and an equal volume of isopropanol was added. The mixture was inverted and centrifuged at 14000 rpm for 10 min. The supernatant was discarded, and the white precipitate was washed with 700 μL of 70% ethanol. The tube was centrifuged at 14000 rpm for 5 min, and the supernatant was discarded. The tube was then air-dried in a fume hood for 10 min. 30 μL of ultrapure water (ddH2O) was added to dissolve the DNA. The DNA solution should be stored at -20 degrees Celsius for later use.

[0060] 2) PCR amplification and sequencing of crRNA sequences in T0 generation rice: Primer pairs U6p-F (as shown in SEQ ID No. 4) and pENTR4-R (as shown in SEQ ID No. 5) were designed for identifying crRNA sequences of A3-#13, A3-#16, A3-#17, and A3-#7. Using genomic DNA solutions from T0 generation plants as templates, and with U6p-F and pENTR4-R as primer pairs, PCR amplification was performed using Phanta Max Super-Fidelity DNA Polymerase (purchased from Nanjing Novizan Biotechnology Co., Ltd.). The PCR products were then directly sequenced using Sanger sequencing.

[0061] Sanger sequencing results showed that the crRNA sequence used in A3-#13 and A3-#16 was OsACC-Pool03-crRNA68 from Pool03 (as shown in SEQ ID No. 6); the crRNA sequence used in A3-#17 was OsACC-Pool03-crRNA69 from Pool03 (as shown in SEQ ID No. 7). Figure 4 The crRNA sequence used in A3-#7 is OsACC-Pool03-crRNA67 from Pool03 (as shown in SEQ ID No. 8), see... Figure 5 .

[0062] 3) PCR amplification and sequencing detection of mutation sites: Specific amplification primers OsACC-F (as shown in SEQ ID No. 9) and OsACC-R (as shown in SEQ ID No. 10) were designed for A3-#7, A3-#13, A3-#16, and A3-#17. Using genomic DNA solutions from T0 and T1 generation plants as templates and the corresponding plant primer pairs as primers, PCR amplification was performed using Phanta Max Super-Fidelity DNA Polymerase (purchased from Nanjing Novizan Biotechnology Co., Ltd.). The PCR products were then directly sequenced using Sanger sequencing.

[0063] Sanger sequencing results from generation T0 of A3-#13, compared with wild-type results, showed a deletion mutation. Specifically, it exhibited a -38bp / -69bp biallelic deletion mutation. OsACC In the gene start codon ATG, position A is 0. 38 bp is deleted from positions 268 to 305 upstream of A, and 69 bp is deleted from positions 232 to 300 upstream of A. The results are shown below. Figure 3In T1 generation plants resistant to quizalofop-P-ethyl, the following mutations were detected: A3-#13-38, a homozygous deletion mutation of -38bp / -38bp occurring at positions 268-305 upstream of the start codon; A3-#13-69, a homozygous deletion mutation of -69bp / -69bp occurring at positions 232-300 upstream of the start codon; and A3-#13-38 / -69, a biallelic deletion mutation of -38bp / -69bp occurring at positions 268-305 and 232-300 upstream of the start codon.

[0064] Sanger sequencing results from generation T0 of A3-#16, compared with wild-type results, showed that A3-#16 contained insertion and deletion mutations. Specifically, it contained homozygous insertion and deletion mutations ranging from +1 to 45 bp. OsACC In the start codon ATG, where A is at position 0, a homozygous mutation occurs between positions 237 and 281 upstream of A, involving an insertion of 1 bp and a deletion of 45 bp. The results are shown in [the table below]. Figure 3 In T1 generation plants resistant to quizalofop-P-ethyl, A3-#16+1-45 homozygous insertion and deletion mutations with positions +1-45bp / +1-45bp upstream of the start codon were detected.

[0065] Sanger sequencing results from generation T0 of A3-#17, compared with wild-type results, showed a deletion mutation. Specifically, it exhibited a -33bp / -68bp biallelic deletion mutation. OsACC In the gene start codon ATG, position A is 0. 33 bp is deleted from positions 219 to 251 upstream of A, and 68 bp is deleted from positions 173 to 240 upstream of A. The results are shown below. Figure 4 In T1 generation plants with high resistance to flupyradifurone, the following mutations were detected: A3-#17-33, a homozygous deletion mutation of -33bp / -33bp occurring at positions 219-251 upstream of the start codon; A3-#17-68, a homozygous deletion mutation of -68bp / -68bp occurring at positions 173-240 upstream of the start codon; and A3-#17-33 / -68, a biallelic deletion mutation of -33bp / -68bp occurring at positions 219-251 and 173-240 upstream of the start codon.

[0066] Sanger sequencing results from generation T0 of A3-#7, compared with wild-type results, showed that A3-#7 contained deletion mutations. Specifically, it exhibited biallelic insertion / deletion and deletion mutations of -29bp / -54bp, i.e., with... OsACC In the gene start codon ATG, position A is 0. 29 bp is deleted from positions 243 to 271 upstream of A, and 54 bp is deleted from positions 209 to 262 upstream of A. The results are shown below. Figure 5In T1 generation plants with high resistance to flupyradifurone, the following mutations were detected: A3-#7-29, a homozygous insertion / deletion mutation of -29 bp occurring at positions 243-271 upstream of the start codon; A3-#7-54, a homozygous deletion mutation of -54 bp / -54 bp occurring at positions 209-262 upstream of the start codon; and A3-#7-29 / -54, a biallelic insertion / deletion mutation of -29 bp / -54 bp occurring at positions 243-271 and 209-262 upstream of the start codon.

[0067] Based on the A3-#7-29, A3-#7-54, A3-#13-38, A3-#13-69, A3-#16+1-45, and A3-#17-33 mutants, the locations of their mutations in the sequence shown in SEQ ID No. 1 are plotted. Figure 8 .

[0068] Example 4: Rice OsACC Mutant anti-ACCase inhibitor herbicides spectrum.

[0069] The agricultural herbicide quizalofop-p-ethyl EC, with an active ingredient content of 15%, was purchased from Ningbo Shiyuan Jinniu Agricultural Technology Co., Ltd. The recommended field dose of quizalofop-p-ethyl EC is 34 g ai / ha, which is recorded as 1 × 1 times the recommended field dose.

[0070] The agricultural commercial pesticide, high-efficiency flupyradifurone EC, with an active ingredient of 10.08%, was purchased from Weifang Xinlv Chemical Co., Ltd. The recommended field dose of high-efficiency flupyradifurone EC is 48.6 g ai / ha, which is recorded as 1 × 1 times the recommended field dose.

[0071] The agricultural commercial herbicide clethodim suspension, with an active ingredient content of 24%, was purchased from Anhui Huaxing Chemical Co., Ltd. The recommended field dose of clethodim suspension is 72 g ai / ha, which is recorded as 1 × 1 times the recommended field dose.

[0072] The quizalofop-P-ethyl EC, quizalofop-P-ethyl EC, and clethodim suspension were diluted with tap water to obtain 2×, 4×, and 8× quizalofop-P-ethyl dilutions, 2× quizalofop-P-ethyl dilutions, and 0.5×, 1×, 1.5×, and 2× clethodim dilutions, respectively.

[0073] T0 generation seeds of A3-#13, A3-#16, and A3-#7 were sown in nutrient soil in seedling pots and cultured in a greenhouse to obtain corresponding T1 generation plants. Tap water (0×) was used as a negative control, and wild-type rice was included as a control. Each treatment had 30 seedlings. When the rice plants reached 2-3 leaves in the greenhouse, they were sprayed with diluted quizalofop-P-ethyl or clethodim at various concentrations using a portable sprayer. After herbicide application, the plants continued to be cultured in the greenhouse. The growth of the T1 generation plants was observed after 14 days. Figure 6 . Figure 6 The results showed that wild-type rice seedlings withered and died under the influence of quizalofop-p-ethyl diluted at 4 times the field recommended dose and clethodim diluted at 1 times the field recommended dose, while the T1 generation plants of A3-#13, A3-#16, and A3-#7 all showed normal growth and were green. These results indicate that the A3-#13, A3-#16, and A3-#7 mutants possess resistance to both quizalofop-p-ethyl and clethodim.

[0074] T0 generation seeds of A3-#17 were sown in nutrient soil in seedling pots and cultured in a greenhouse to obtain corresponding T1 generation plants. Tap water (0×) was used as a negative control, and wild-type rice was included as a control. Each treatment had 30 seedlings. When the rice plants grew to 2-3 leaves in the greenhouse, they were sprayed with diluted quizalofop-P-ethyl, haloxyfop-methyl, or clethodim at various concentrations using a mobile sprayer. After herbicide application, the plants continued to be cultured in the greenhouse. The growth of the T1 generation plants was observed after 14 days. Figure 7 . Figure 7 The results showed that wild-type rice seedlings withered and died under the influence of 4 times the field recommended concentration of quizalofop-P-ethyl, 2 times the field recommended concentration of fluazinam, and 1 time the field recommended concentration of clethodim. In contrast, the T1 generation plants of A3-#17 all exhibited normal growth and remained green. These results indicate that the A3-#17 mutant possesses resistance to quizalofop-P-ethyl, fluazinam, and clethodim.

Claims

1. A type of rice OsACC Gene mutant, the rice OsACC Gene mutants are deletion mutants; among them, Deletion mutations occur in rice OsACC In the gene promoter, the sequence of the nucleic acid before deletion mutation is shown in SEQ ID No. 1; the length of the deleted nucleic acid sequence ranges from 29 bp to 97 bp, among which, OsACC The A in the gene start codon ATG is at position 0. The deleted nucleic acid occurs at positions 305 to 209 upstream of the start codon ATG, and at least the bases located at positions 271 to 243 upstream of the start codon ATG are deleted.

2. The rice according to claim 1 OsACC Gene mutants, characterized by, The length of the deleted nucleic acid sequence ranged from 29 bp to 69 bp, among which, OsACC The A in the gene start codon ATG is at position 0. The deleted nucleic acid occurs within positions 300 to 232 upstream of the start codon ATG, and at least positions 271 to 243 upstream of the start codon ATG are deleted.

3. The rice according to claim 2 OsACC Gene mutants, characterized by, The length of the deleted nucleic acid sequence is 29 bp, and it is... OsACC The A in the gene start codon ATG is at position 0, and the deleted nucleic acid occurs at positions 271 to 243 upstream of the start codon ATG; and / or The deleted nucleic acid sequence is 45 bp in length, and... OsACC The A in the gene start codon ATG is at position 0, and the deleted nucleic acid occurs at positions 281 to 237 upstream of the start codon ATG; and / or The deleted nucleic acid sequence is 69 bp in length, and... OsACC The A in the gene start codon ATG is at position 0, and the deleted nucleic acid occurs at positions 300 to 232 upstream of the start codon ATG.

4. A type of rice OsACC Gene mutant, the rice OsACC Gene mutants are deletion-merged insertion mutants, in which... Deletion-merge-insertion mutations occur in rice OsACC In the gene promoter, the sequence of the deleted and inserted nucleic acid before the mutation is shown in SEQ ID No. 1; the length of the deleted nucleic acid sequence is 29 bp to 97 bp, and the length of the inserted nucleic acid sequence is 1 bp; OsACC The A in the start codon ATG is at position 0. The deleted nucleic acid occurs within positions 305 to 209 upstream of the start codon ATG, and at least positions 271 to 243 upstream of the start codon ATG are deleted. OsACC The A in the gene start codon ATG is at position 0, and the inserted nucleic acid occurs at positions 271 to 243 upstream of the start codon ATG.

5. The rice according to claim 4 OsACC Gene mutants, characterized by, The sequence of the inserted nucleic acid is C.

6. The rice according to any one of claims 1 to 5 OsACC The application of gene mutants in rice ACCase inhibitor herbicides, wherein the rice variety is Nanjing 46 or Nipponbare.

7. The application according to claim 6, characterized in that, The ACCase inhibitor herbicide is at least one of quizalofop-P-ethyl, haloxyfop-P-ethyl, and clethodim.

8. A method for conferring resistance to ACCase inhibitor herbicides on rice, which involves deleting certain components from the rice genome through gene editing or homologous recombination. OsACC A subset of bases in the gene promoter, and optionally directed towards the... OsACC The gene promoter inserts a partial base to obtain the rice as described in any one of claims 1 to 5. OsACC The rice variety is Nanjing 46 or Nipponbare, which is achieved through gene mutants.

9. The method according to claim 8, characterized in that, The method includes the following steps: 1) Obtain the pHZLib-Cas12i3 vector, or the pHZ33 and pUbi-IEE-Cas12i3 vector; wherein, the pHZLib-Cas12i3 vector is constructed by the following operation: replacing the DR-crRNA-BsaI-BsaI-DR element in pHZ33 with the suicide gene ccdB to obtain the pHZ33-ccdB vector; integrating pHZ33-ccdB with pUbi-IEE-Cas12i3 into a vector to obtain the pHZLib-Cas12i3 vector; 2) Obtain a crRNA sequence or target sequence for gene editing, wherein the crRNA sequence is as shown in SEQ ID Nos. 6 or 8; and the target sequence is located at positions 34 to 56 of the sequence shown in SEQ ID Nos. 6 or 8. 3) Replace the ccdB gene on the pHZLib-Cas12i3 vector with the crRNA, thereby cloning the crRNA sequence into the pHZLib-Cas12i3 vector to obtain pHZLib-Cas12i3-OsACCcrRNA; or clone the target sequence into the pHZ33 vector to obtain the pHZ33-OsACCSpacer vector, and then integrate the pHZ33-OsACCSpacer with the pUbi-IEE-Cas12i3 vector into a single vector to obtain pUbi-IEE-Cas12i3-HZ33-OsACCSpacer; 4) pHZLib-Cas12i3-OsACCcrRNA or pUbi-IEE-Cas12i3-HZ33-OsACCSpacer were transformed into Agrobacterium and infected rice callus tissue to screen for rice lines resistant to ACCase inhibitor herbicides.

10. The method according to claim 8 or 9, characterized in that, The ACCase inhibitor herbicide is at least one of quizalofop-P-ethyl, haloxyfop-P-ethyl, and clethodim.

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