Quality-improving and efficiency-improving planting method for rice in saline-alkali soil

Abstract

According to the method, germplasm T07339 of a salt-tolerant rice core resource library established in the earlier stage is used as a parent, molecular breeding and haploid anther culture technologies are adopted, the salt tolerance of an existing main variety is improved, and the quality and efficiency of the rice in the saline-alkali soil are improved. A microbial diversity sequencing technology is comprehensively utilized to analyze rhizosphere dominant functional bacteria of saline-alkali-tolerant rice and salt-tolerant functional bacteria of a patent applied by a project team, so that the special rice soil conditioner for saline-alkali soil is developed, and the invention relates to the technical field of saline-alkali soil rice planting. According to the quality-improving and efficiency-improving planting method for the rice in the saline-alkali soil, a VIP + n three-dimensional comprehensive quality-improving and efficiency-improving technology special for the rice in the saline-alkali soil is established, namely comprehensive combination of a Variety variety, Irrigation reasonable irrigation and pH adjustment. From saline-alkali tolerant rice to the soil improvement agent, from rhizosphere fertilization to leaf three-dimensional addition, and from inorganic and organic dosage form composite conditioning, the compatibility of the saline-alkali tolerant rice-saline-alkali soil conditioner is optimized, three-dimensional comprehensive quality and efficiency improvement is realized, and small-scale demonstration application is realized.

Description

Technical Field

[0001] The invention relates to the technical field of rice planting in saline-alkali land, and in particular to a method for improving the quality and efficiency of rice planting in saline-alkali land. Background Art

[0002] China has abundant saline-alkali land resources, most of which are deep and flat, and about 80% can be developed into arable land, which is a land resource with great potential. Therefore, improving and utilizing saline-alkali land and allowing rice to settle in saline-alkali land areas has become an important issue that the coastal grain industry urgently needs to solve.

[0003] Rice is a moderately salt-sensitive crop. Its roots absorb salt and secrete organic acids, making it the preferred food crop for improving saline-alkali land. Currently, there are few salt-tolerant rice varieties suitable for planting on my country's coastal tidal flats, especially salt-tolerant japonica rice varieties. Therefore, it is urgent to breed new salt-tolerant, high-quality, and high-yield rice varieties suitable for planting on my country's coastal tidal flats.

[0004] Engineering measures as the main method and chemical methods as the auxiliary method are important and effective measures for the improvement of saline-alkali land. Engineering measures mainly include irrigation to wash salt, drainage to remove salt (drainage through concealed pipes), and soil improvement. In addition to engineering measures, the application of organic fertilizers (straw, silt, fly ash, etc.) and the planting of green manure plants, water-land rotation, etc. also play different roles. Commonly used chemical improvers for saline-alkali land include gypsum, phosphogypsum, flue gas desulfurization gypsum, green vitriol, and commercialized soil improvers. In addition, in terms of microbial soil improvement, the use of mycorrhizal fungi has also achieved good results. Different improvement measures have their own characteristics in terms of effect, cost, and difficulty of implementation.

[0005] The salt-alkali tolerance of rice mainly depends on its own genotype, and is also affected by external environment such as exogenous chemicals and cultivation measures. By adding salt-alkali-tolerant microbial agents, the microbial environment can be improved, nutrient utilization can be increased, and the salt-alkali tolerance of crops can be effectively improved. Rhizosphere microorganisms are crucial to the growth, stress adaptability and yield of crops. However, plant genetic variation can determine the composition of underground microbial communities, among which root secretions play a key role in selecting rhizosphere microorganisms.

[0006] With the idea of ​​"plants first, soil improvement as the basis, water guarantee, microbial regulation, and plant-soil-microorganism ecosystem integration", referring to the farmland rice cadmium reduction technology developed by the expert team of Hunan Academy of Agricultural Sciences, we have innovated the "VIP+n" all-round three-dimensional quality improvement and efficiency enhancement technology for saline-alkali rice (V, Variety, selection of salt (alkali) tolerant rice varieties; I, Irrigation, optimization of water management; P, soil pH, application of gypsum and other soil improvers; n, inorganic silicon fertilizers, organic composite bacteria and other conditioners). Based on salt (alkali) tolerant rice varieties, by analyzing the rhizosphere dominant functional microorganisms of salt-alkali tolerant rice, we have developed saline-alkali rice compound conditioners based on the fermentation of salt-alkali tolerant microorganisms, and combined the inorganic and organic formulations to develop all-round saline-alkali rice quality improvement and efficiency enhancement technologies to tap the production potential of adverse agricultural ecological zones. The breeding of salt-alkali tolerant rice varieties and the development and utilization of three-dimensional and all-round quality and efficiency improvement technologies have direct ecological and economic benefits for achieving sustained increases in salt-alkali tolerant rice production, improving the efficiency of saline land use, improving the ecological environment, achieving agricultural efficiency, and increasing farmers' and corporate income. Summary of the invention

[0007] 1. Technical issues to be resolved

[0008] In view of the shortcomings of the prior art, the present invention provides a method for improving the quality and efficiency of rice cultivation in saline-alkali land. In view of the key technical bottleneck problems such as low yield and poor efficiency of rice cultivation on coastal tidal flats, salt-alkali-tolerant rice varieties are bred, special soil conditioners for saline-alkali rice based on salt-alkali-tolerant microorganisms are developed, and three-dimensional, all-round comprehensive utilization technology special for saline-alkali rice fields is developed. Through the effective combination of salt-alkali-tolerant rice varieties and special composite conditioning bacterial fertilizers (microbial agents) for saline-alkali rice fields, the improvement of saline-alkali land rice cultivation technology and the improvement of quality and efficiency of saline-alkali land production capacity are achieved.

[0009] (II) Technical solution

[0010] To achieve the above objectives, the present invention is implemented through the following technical scheme: a method for improving the quality and efficiency of rice cultivation in saline-alkali land, specifically comprising the following steps:

[0011] S1. Breeding of salt-alkali tolerant rice: Use developed molecular markers to track the genotypes of selected materials through hybridization and backcrossing methods, aggregate salt-alkali tolerant genes into the main high-yield and high-quality rice, plant high-generation materials in experimental bases and identify their agronomic traits in the field, screen new salt-alkali tolerant, high-quality and high-yield rice materials, and breed new salt-alkali tolerant rice varieties;

[0012] S2. Comprehensively utilize the microbial community structure to analyze the dominant functional microorganisms in the rhizosphere of salt-alkali tolerant rice: select 10 rice species with different salt-alkali tolerance, collect soil and rhizosphere samples from their planting, extract DNA and perform microbial community diversity sequencing to analyze the dominant functional bacteria in the rhizosphere of salt-alkali tolerant rice;

[0013] S3, creating a salt-alkali tolerant composite bacterial agent, and developing a saline-alkali soil conditioning agent for improving the quality and efficiency of salt-alkali tolerant rice: compounding the rhizosphere dominant functional bacteria of the salt-alkali tolerant rice separated in step S2, preparing a composite bacterial fertilizer of the rhizosphere functional bacteria of the salt-alkali tolerant rice, applying it to the root area of ​​the rice, analyzing the salt-alkali tolerance, yield and quality traits of the rice, and comprehensively analyzing the quality and efficiency improvement of the saline-alkali land rice, and determining the saline-alkali land soil conditioning bacterial fertilizer for the salt-alkali tolerant rice;

[0014] S4. Optimize the compatibility of salt-alkali tolerant compound bacterial agents with agricultural and commercial soil conditioners, and develop soil conditioners suitable for high-quality rice cultivation in saline-alkali land: Combine silicon fertilizers, develop soil conditioners for saline-alkali land based on salt-alkali tolerant bacterial fertilizers, optimize the compatibility of salt-alkali tolerant compound bacterial agents with agricultural and commercial soil conditioners, analyze the salt-alkali tolerance, yield and quality traits of saline-alkali land rice after adding the formulated saline-alkali soil compound conditioners, comprehensively evaluate the adaptability of salt-alkali tolerant rice saline-alkali soil compound conditioners, and develop soil conditioners suitable for high-quality rice cultivation in saline-alkali land;

[0015] S5. Establish VIP and n three-dimensional all-round quality improvement and efficiency enhancement model for rice cultivation in saline-alkali land.

[0016] Preferably, in step SS, the dominant functional bacteria in the rhizosphere of salt-alkali tolerant rice are isolated, the functional bacteria are sequenced for verification, the salt-alkali resistance of the dominant functional bacteria in the rhizosphere is identified, and then the salt-alkali tolerant strains are combined, the fermentation conditions are optimized, and large-scale culture is carried out.

[0017] Preferably, the sequencing functional bacteria are rDNA bacteria with full-length 16S or fungi with ITS gene in the transcribed spacer region.

[0018] Preferably, the agricultural and commercial soil conditioner in step S4 is an inorganic combined with organic soil conditioner.

[0019] Preferably, the VIP and n three-dimensional all-round quality improvement and efficiency enhancement mode is a heavy metal pollution remediation and management mode of VIP and n, that is, a comprehensive combination of Variety, Irrigation and pH adjustment, from salt-alkali tolerant rice to soil improvers, from rhizosphere fertilization to three-dimensional leaf addition, inorganic and organic formulations are compounded for conditioning, and the compatibility of salt-alkali tolerant rice saline-alkali soil conditioners is optimized to achieve three-dimensional all-round quality improvement and efficiency enhancement, and then small-scale demonstration and application.

[0020] Preferably, in step S2, the microbial community structure analyzes the dominant microorganisms in the rhizosphere of salt-alkali tolerant rice, selects 10 rice plants with different salt-alkali tolerance, digs out their roots, collects the soil tightly adhered to the root surface, extracts the total DNA of the rhizosphere soil, analyzes the high-throughput sequencing data of the microbial community structure, obtains the differences in the microbial population structure and abundance in different rhizosphere soil samples, and focuses on the diversity and composition of the microbial community carrying the reported salt-alkali tolerance functional genes.

[0021] Preferably, in step S2, the corresponding culture medium components are designed according to the species information of the salt-alkali-tolerant rice rhizosphere specific microorganisms obtained above, rhizosphere soil samples of the salt-alkali-tolerant rice are collected, and the root suspension is directly diluted by gradient dilution and then applied to the corresponding culture medium for separation and purification to obtain pure bacteria of the rhizosphere specific microorganisms of the salt-alkali-tolerant rice, which are classified and identified according to the morphology of the colonies, and the size, color, surface characteristics and texture of the colonies are observed, and the hyphae, fruiting bodies, spores and spore-producing structures are observed under a microscope.

[0022] Preferably, in step S2, a salt-alkali concentration gradient is set, tolerant bacteria are screened on a plate, and the separated salt-alkali tolerant rice rhizosphere dominant functional bacteria are coated on a medium containing salt and alkali for screening. On the other hand, under liquid culture conditions, the types and contents of organic acids secreted by different strains, as well as the effects on the pH of the culture medium are analyzed by HPLC, and the internal and external H of the cell membranes of different strains are analyzed by non-destructive micro-measurement technology. + 、Na + and Cl - Flow rate.

[0023] (III) Beneficial effects

[0024] The present invention provides a method for improving the quality and efficiency of rice cultivation in saline-alkali land. Compared with the prior art, the method has the following beneficial effects: the method for improving the quality and efficiency of rice cultivation in saline-alkali land uses the germplasm T07339 of the salt-tolerant rice core resource library established in the early stage as the parent, adopts molecular breeding and haploid anther culture technology to improve the salt tolerance of the existing main promoted varieties, and comprehensively utilizes microbial diversity sequencing technology to analyze the rhizosphere dominant functional bacteria of salt-alkali tolerant rice and the salt-tolerant functional bacteria for which the project team has applied for a patent, thereby developing a rice soil conditioner dedicated to saline-alkali land, and establishing a three-dimensional and all-round quality and efficiency improvement technology dedicated to saline-alkali land rice, namely, Variety (variety), Irrigation (rational irrigation) and pH (adjusting acidity and alkalinity) all-round combination. From salt-alkali tolerant rice to soil improver, from rhizosphere fertilization to three-dimensional addition to leaves, inorganic and organic formulations are compounded for conditioning, and the compatibility of salt-alkali tolerant rice-salt-alkali soil conditioner is optimized to achieve three-dimensional and all-round quality and efficiency improvement, and then small-scale demonstration application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] See also Figure 1 The embodiment of the present invention provides a technical solution: a method for improving the quality and efficiency of rice cultivation in saline-alkali land, which specifically comprises the following steps:

[0028] S1. Accurate identification of rice phenotypes on saline-alkali land: Analysis of salt-alkali tolerance of rice seedlings. Referring to the method of Cai Xiaoxi et al. (Acta Physiologica Sinica, 2020, 56(12): 2683), rice seeds were soaked in a triangular bottle for germination, and when they broke through the chest and showed white, they were transplanted into nutrient pots and cultured until the three-leaf stage. Rice seedlings with consistent growth were selected and irrigated with a solution containing 0.3% NaCl and 200mmol·L-1NaHCO3 (pH 8.4) for 15 days of saline-alkali stress treatment. The growth status of the plants was observed, and the survival rate and relative water content were measured. Three independent biological replicates were set for each treatment, and no less than 60 rice seedlings of each strain were included in each biological replicate.

[0029] Determination of physiological indicators under saline-alkali stress. According to the method of Cai Xiaoxi et al. (Journal of Plant Physiology, 2020, 56(12): 2683), the aboveground part of rice seedlings was taken after treatment, and the Na+ and K+ contents were determined by flame photometry, and the K+ / Na+ value was calculated; the activities of peroxidase POD and catalase CAT were determined, and nitroblue tetrazolium NBT and 3,3'-diaminobenzidine DAB staining solution were used for staining. 20 samples were measured for each indicator, and the electrolyte leakage rate was determined using a conductivity meter.

[0030] Identification of salt-alkali tolerance of rice agronomic traits. Referring to the method of Zhang Xin et al. (Soil and Crops, 2020, 9(03): 260), the relative inhibition rate of different agronomic traits was used as an evaluation index for salt-alkali tolerance. At maturity, the number of effective tillers of rice was investigated. According to the average number of tillers per plant, three representative plants were selected to examine agronomic traits such as plant height, panicle length, number of panicles, number of grains per panicle, and 1,000-grain weight. Finally, the yield was measured in different plots. The relative inhibition rate (RI) was used to indicate the strength of rice salt-alkali tolerance. The larger the value, the more severe the salt-alkali stress and the weaker the salt-alkali tolerance. Referring to the method of Li Hongyu et al. (Journal of Nuclear Agricultural Sciences, 2020, 34(08):1862), digital scanning was performed using a root morphology scanner ScanMaker i800 (Microtek, China), and then the root morphology parameters such as total root length, total root area, total root volume, average root diameter, number of root tips, and number of root forks were analyzed using the LA-S plant root analysis system (Shanghai Zhongjing Technology Co., Ltd.).

[0031] Study on gene expression patterns: The roots, leaves, and ears of rice at different developmental stages were collected, total RNA was extracted, and qRT-PCR technology was used to analyze the expression differences of genes in different parts.

[0032] S2. Breeding of salt-alkali tolerant rice varieties: Molecular breeding of salt-alkali tolerant rice. Through hybridization and backcrossing methods, the developed molecular markers are used to track the genotypes of the selected materials, and the salt-alkali tolerant genes are aggregated into the main high-yield and high-quality rice. The high-generation materials are planted in Lianyungang Dongxin Farm and the agronomic traits are identified in the field to screen new salt-alkali tolerant, high-quality and high-yield rice materials.

[0033] S3. Analysis, isolation and identification of rhizosphere microorganisms of salt-alkali tolerant rice: Analysis of the dominant rhizosphere microorganisms of salt-alkali tolerant rice by microbial community structure. Ten rice plants with different salt-alkali tolerance were selected, their roots were dug, and the soil tightly adhered to the surface of the root system (rhizosphere soil) was collected. The total DNA of the rhizosphere soil was extracted, and high-throughput sequencing of bacterial 16S rDNA and fungal 18S rDNA was performed. Referring to the methods of Wei et al. (2019, Sci Adv. 5: eaaw0759), Yurgel et al. (2019, Front Microbiol. 10: 1682), Chen et al. (2021, Plant Signal Behav. 16: 1854507) and Cao Min et al. (2020, Microbiology Bulletin, 47: 2877), the high-throughput sequencing data of microbial community structure were analyzed to obtain the differences in microbial population structure and abundance in different rhizosphere soil samples. Focus on the diversity and composition of microbial communities carrying reported salt-alkali tolerance functional genes.

[0034] Isolation and identification of dominant functional bacteria in the rhizosphere of salt-alkali tolerant rice. According to the above-obtained information on the specific microorganisms in the rhizosphere of salt-alkali tolerant rice, the corresponding culture medium components were designed. The rhizosphere soil samples of salt-alkali tolerant rice were collected (Niu et al., 2017, Proc Natl Acad Sci USA. 114: E2450; Kwak et al., 2018, Nat Biotechnol 36: 1100), and the root suspension was directly diluted by gradient, and then applied to the corresponding culture medium for separation and purification to obtain pure bacteria of the rhizosphere specific microorganisms of salt-alkali tolerant rice. Classification and identification were carried out according to the morphology of the colonies, and the size, color, surface characteristics and texture of the colonies were observed, and the hyphae, fruiting bodies, spores, spore-producing structures, etc. were observed microscopically; the 16S rDNA (bacteria) or 18S rDNA gene (fungus) was sequenced for identification. The classification and identification results were compared with the above-obtained information on the specific microorganisms in the rhizosphere of salt-alkali tolerant rice, and finally the pure culture of the target strain was obtained. Primers were designed based on reported rhizospheric functional bacteria (such as salt-tolerant bacteria), relevant functional genes were amplified, and the functions of the strains were determined (Wu et al., 2018, World J Microbiol Biotechnol. 34: 177; Jia et al., 2019, Chemosphere. 218: 1061; Zhang et al., 2019, Nature Biotechnol. 37: 676; Chen et al., 2021, Plant Signal Behav. 16: 1854507).

[0035] Screening of salt-alkali tolerant strains and identification of their secretions. Set up a salt-alkali concentration gradient, screen tolerant bacteria on a plate, and spread the isolated salt-alkali tolerant rice rhizosphere dominant functional bacteria on a salt-alkali containing culture medium for screening. On the other hand, under liquid culture conditions, the types and contents of organic acids secreted by different strains, as well as the effects on the pH of the culture medium, were analyzed by HPLC, and the flow rates of H+, Na+ and Cl- inside and outside the cell membrane of different strains were analyzed by non-destructive micro-measurement technology (NMT).

[0036] S4. Analysis of the salt-alkali tolerance effect of plants and functional microorganisms: Potted simulation experiment: Select the rice and mother parent (mainly promote high-quality and high-yield rice varieties) bred by salt-alkali tolerance backcrossing for potted experiments. In the salinity conditions of the saline-alkali land in the potted soil simulation experimental base, inoculate strains with different salt-alkali tolerance levels to study the number of rhizosphere microorganisms, community types, and salt-alkali content in plants under different combinations. Study the migration and transport ratio of salt from the soil-plant interface at different growth stages, and screen out efficient rice-functional microorganism combinations under saline-alkali stress conditions.

[0037] Field experiments in saline-alkali land: The high-efficiency strain-rice combination selected in the pot simulation experiment is applied to saline-alkali soil. During the entire growth period of rice, the accumulation of salt in different tissues and organs at different growth stages is investigated, with special attention paid to the accumulation and distribution of salt in roots, stems, leaves, pods, and grains at maturity.

[0038] S5. Compound soil conditioner for saline-alkali land: refer to the methods of Liu Liping et al. (2014) and Tang Yuqing et al. (2015), and use agricultural and commercial soil conditioners in combination with microbial functional bacteria. Refer to the heavy metal pollution remediation and management technology model of VIP+n (Chen Jiali et al., 2020), V stands for Variety, which means the selection of salt-alkali tolerant varieties; I stands for Irrigation, which means reasonable irrigation; P stands for pH adjustment; n1 represents the application of soil conditioners (adjusting soil pH and fertilizers); n2 represents the application of organic fertilizers; and n3 represents other additives. Refer to the application of soil conditioners in saline-alkali land improvement (Jiang Zengming et al., 2014) to optimize the compounding scheme of VIP+n saline-alkali land soil conditioners.

[0039] Feasibility analysis: Proficient in the research and development of dominant functional bacteria in the plant rhizosphere based on the analysis of microbial community structure: Since 2012, we have been engaged in the research of rice salt-alkali tolerance, built a core resource library of salt-tolerant rice, bred a number of salt-tolerant varieties (Yantianyu No. 1, Yantianyu No. 2, Lianjian No. 7 and Lianjian No. 9 are under review), and published 2 SCI papers on salt tolerance research. In addition, Professor Tan Mingpu of Nanjing Agricultural University, a cooperative unit, has been focusing on the research and development of functional microorganisms in the plant rhizosphere since 2016, and has established stable and reliable microbial isolation and identification, bacterial agent compounding and related operation technologies, and has made good progress in the research of salt-tolerant microorganisms in rice roots.

[0040] Through the cooperative enterprise Jiangsu Yancheng Dafeng Huafeng Seed Co., Ltd., located in Dafeng District, Yancheng City, Jiangsu Province, with a large area of ​​tidal flats around it, it is one of the largest rice breeding and promotion enterprises in the province. These provide field management guarantees for the establishment of a special VIP+n three-dimensional, all-round quality improvement and efficiency enhancement model for rice-suitable saline-alkali land, ensuring that the project can be demonstrated and applied on a large scale in the later stage.

[0041] Meanwhile, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0042] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0043] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for improving the quality and efficiency of rice cultivation in saline-alkali land, characterized in that: The specific steps include: S1. Breeding of salt-alkali tolerant rice: Use developed molecular markers to track the genotypes of selected materials through hybridization and backcrossing methods, aggregate salt-alkali tolerant genes into the main high-yield and high-quality rice, plant high-generation materials in experimental bases and identify their agronomic traits in the field, screen new salt-alkali tolerant, high-quality and high-yield rice materials, and breed new salt-alkali tolerant rice varieties; S2. Comprehensively utilize the microbial community structure to analyze the dominant functional microorganisms in the rhizosphere of salt-alkali tolerant rice: select 10 rice species with different salt-alkali tolerance, collect soil and rhizosphere samples from their planting, extract DNA and perform microbial community diversity sequencing to analyze the dominant functional bacteria in the rhizosphere of salt-alkali tolerant rice; S3, creating a salt-alkali tolerant composite bacterial agent, and developing a saline-alkali soil conditioning agent for improving the quality and efficiency of salt-alkali tolerant rice: compounding the rhizosphere dominant functional bacteria of the salt-alkali tolerant rice separated in step S2, preparing a composite bacterial fertilizer of the rhizosphere functional bacteria of the salt-alkali tolerant rice, applying it to the root area of ​​the rice, analyzing the salt-alkali tolerance, yield and quality traits of the rice, and comprehensively analyzing the quality and efficiency improvement of the saline-alkali land rice, and determining the saline-alkali land soil conditioning bacterial fertilizer for the salt-alkali tolerant rice; S4. Optimize the compatibility of salt-alkali tolerant compound bacterial agents with agricultural and commercial soil conditioners, and develop soil conditioners suitable for high-quality rice cultivation in saline-alkali land: Combine silicon fertilizers, develop soil conditioners for saline-alkali land based on salt-alkali tolerant bacterial fertilizers, optimize the compatibility of salt-alkali tolerant compound bacterial agents with agricultural and commercial soil conditioners, analyze the salt-alkali tolerance, yield and quality traits of saline-alkali land rice after adding the formulated saline-alkali soil compound conditioners, comprehensively evaluate the adaptability of salt-alkali tolerant rice saline-alkali soil compound conditioners, and develop soil conditioners suitable for high-quality rice cultivation in saline-alkali land; S5. Establish VIP and n three-dimensional all-round quality improvement and efficiency enhancement model for rice cultivation in saline-alkali land.

2. A method for improving the quality and efficiency of rice cultivation in saline-alkali land according to claim 1, characterized in that: In the step SS, the dominant functional bacteria in the rhizosphere of salt-alkali tolerant rice are isolated, the functional bacteria are sequenced for verification, the salt-alkali resistance of the dominant functional bacteria in the rhizosphere is identified, and then the salt-alkali tolerant strains are combined, the fermentation conditions are optimized, and large-scale culture is carried out.

3. A method for improving the quality and efficiency of rice cultivation in saline-alkali land according to claim 2, characterized in that: The sequencing functional bacteria are rDNA bacteria with full-length 16S or fungi with ITS gene in the transcription spacer region.

4. The method for improving the quality and efficiency of rice cultivation in saline-alkali land according to claim 1, characterized in that: The agricultural and commercial soil conditioner in step S4 is a soil conditioner that combines an inorganic type with an organic type.

5. The method for improving the quality and efficiency of rice cultivation in saline-alkali land according to claim 1, characterized in that: The VIP and n three-dimensional and all-round quality improvement and efficiency enhancement model is a heavy metal pollution remediation and management model for VIP and n, that is, a comprehensive combination of variety, irrigation and pH adjustment, from salt-alkali tolerant rice to soil improvers, from rhizosphere fertilization to three-dimensional foliar addition, inorganic and organic formulations are compounded for conditioning, and the compatibility of salt-alkali tolerant rice saline-alkali soil conditioners is optimized to achieve three-dimensional and all-round quality improvement and efficiency enhancement, and then small-scale demonstration and application.

6. The method for improving the quality and efficiency of rice cultivation in saline-alkali land according to claim 1, characterized in that: In step S2, the microbial community structure analyzes the dominant microorganisms in the rhizosphere of salt-alkali tolerant rice, selects 10 rice plants with different salt-alkali tolerance levels, digs out their roots, collects soil tightly adhered to the root surface, extracts total DNA from the rhizosphere soil, analyzes high-throughput sequencing data of the microbial community structure, obtains differences in microbial population structure and abundance in different rhizosphere soil samples, and focuses on the diversity and composition of microbial communities carrying reported salt-alkali tolerance functional genes.

7. The method for improving the quality and efficiency of rice cultivation in saline-alkali land according to claim 1, characterized in that: In the step S2, the corresponding culture medium components are designed according to the species information of the salt-alkali-tolerant rice rhizosphere specific microorganisms obtained above, and the rhizosphere soil samples of the salt-alkali-tolerant rice are collected. The root suspension is directly diluted by gradient and then applied to the corresponding culture medium for separation and purification to obtain pure bacteria of the rhizosphere specific microorganisms of the salt-alkali-tolerant rice, and the bacteria are classified and identified according to the morphology of the colonies, and the size, color, surface characteristics and texture of the colonies are observed, and the hyphae, fruiting bodies, spores and spore-producing structures are observed under a microscope.

8. The method for improving the quality and efficiency of rice cultivation in saline-alkali land according to claim 1, characterized in that: In step S2, a salt-alkali concentration gradient is set to screen tolerant bacteria on a plate, and the separated salt-alkali tolerant rice rhizosphere dominant functional bacteria are coated on a salt-alkali containing culture medium for screening. On the other hand, under liquid culture conditions, the types and contents of organic acids secreted by different strains, as well as the effects on the pH of the culture medium are analyzed by HPLC, and the internal and external H of the cell membranes of different strains are analyzed by non-destructive micro-testing technology. + 、Na + and Cl - Flow rate.

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