As China’s economy enters the stage of high-quality development， the development model of hog industry is facing an important transformation from focusing on expanding quantity to emphasizing improving quality. There is a need to make concerted efforts in various aspects such as stabilizing production and supply， risk prevention and control， improving quality and efficiency， and being environmentally friendly. Based on the analysis of the practical experiences formed during the development process of the hog industry in developed countries internationally， and combined with the actual development of China’s hog industry， the following suggestions were proposed to continue to promote the integrated development of the hog industry chain， fully leverage the supporting role of science and technology， further strengthen the capability to prevent and control epidemic diseases， vigorously promote a recycling agricultural production model that combines breeding with farming， and improve the hog industry and price regulation system，which provided a reference for promoting the transformation and upgrading of China’s hog industry and achieving high-quality development of the industry.
Wheat yield directly impacts food security in China， but various abiotic stresses such as drought， low temperature， salt and high temperature severely constrain wheat production. In previous analysis， transcriptomic data revealed differential expression of wheat TaCOBL-5D under multiple abiotic stresses. TaCOBL-5D and its homologous genes TaCOBL-5A and TaCOBL-5B were cloned and obtained， and the comprehensive bioinformatics and expression pattern were analyzed. The results showed that TaCOBL-5 genes exhibited significant conservation in gene structure， protein tertiary structure， conserved domains， and promoter regulatory elements with COBL genes from other species. TaCOBL-5 genes exhibited the highest expression level in roots and responded differently to various abiotic stresses， especially significantly down-regulated under drought stress， indicating its importance under drought stress； it also showed different responses to low temperature， high temperature， and salt stress. In addition， the expression level of the TaCOBL-5D gene varied significantly among different drought-resistant and high-temperature-resistant materials， further suggesting its important role in stress resistance. These findings laid the foundation for further understanding of the function of COBL genes in wheat and provided scientific support for wheat breeding efforts aimed at enhancing stress tolerance.
Dwarf stem resources are the material basis for crop dwarf breeding， exploring dwarf stem gene resources is of great significance in breeding for dwarf crop cultivars. With the aim to clarifing the genetic characteristics and dwarf mechanism of a dwarf mutant 20F421 which was identified from radiation mutagenesis mutations using 252CF fission fast neutrons using an elite maize inbred line KWS49， the dwarf stalk mutant 20F421 was as material to construct F1 and F2 isolated populations by hybridizing with maize inbred lines PH6WC， B73， Mo17 and KWS49， respectively， and analyzed the inheritance pattern of dwarf stalk traits， and used （20F421/B73） F2 as the localization population， and transcriptome sequencing combined with bulked segregant RNA-seq （BSR-seq） methods were used for initial mapping of mutant genes. The results showed that compared with KWS49， the plant height of 20F421 was 95.2 cm which reduced by 47.89%， the ear height was 23.9 cm which reduced by 64.54%， the internodes were significantly shortened， the leaves were more erect and dense， and the self-inbreeding was good. Genetic analysis showed that the separation rate of wild type （high stem） and mutant （dwarf stem） plant traits in the F2 isolated population conformed to the 3∶1， indicating that the mutant was controlled by a single nuclear recessive gene. The BSR-seq results map the mutant gene between chromosome 177~255 Mb. By comparing with the B73 reference genome， it was found that the interval contained the dwarf stalk gene Br2， so the allele detection of 20F421 and br2 mutant hybridization were detected， and the plant height of F1 and F2 did not have trait separation， showing the phenotypes of 20F421 and br2 mutant， and it was speculated that the dwarf stalk mutant gene in 20F421 was an allele mutation of the dwarf stalk gene Br2. The results of this study would lay a foundation for further fine localization and cloning of mutant genes， and also provide important genetic resources and theoretical support for the analysis of maize dwarf mechanism and the breeding of new dwarf maize varieties.
Potassium is an essential element for crop growth. It is of great significance to explore genes that improve crop potassium absorption capacity and enhance crop tolerance to potassium deficiency. In this study， ‘Jigu 45’ was used as material and its seedlings were subjected to potassium deficiency stress for 7 d at the 6-leaf stage. By analyzing agronomic indicators and transcriptome， the relevant genes and expression regulation of potassium deficiency stress were analyzed and explored. The results showed that potassium deficiency stress affected the growth and development of foxtail millet plants： the plant height， leaf width， leaf length， stem width， aboveground dry weight and chlorophyll content were lower then those of CK， while the root length and root surface area significantly increased. Transcriptome analysis showed that 217 genes were upregulated and 38 genes were downregulated after potassium deficiency stress. GO functional enrichment revealed that differentially expressed genes were mainly enriched in the structural components of ribosomes， organic nitrogen compound metabolism processes， protein metabolism processes， cellular protein metabolism processes， and membraneless organelles etc. The KEGG functional enrichment results determined that differentially expressed genes were mainly enriched in 19 pathways， including ribosomes， plant hormone signal transduction and glutathione metabolism etc. Subsequently， 35 genes significantly correlated with hormone expression， 19 differentially expressed genes related to oxidative stress， 10 transcription factor families， and 11 genes related to transduction signals were screened， as well as 1 gene related to sugar metabolism of amino acids and nucleotides. The candidate gene Seita.9G193900 belonged to the CYP45084A subfamily and was a key enzyme regulating S-type lignin synthesis； Seita.5G36500 belonged to WRKY family， which regulated the expression of disease response genes such as PAD3； Seita.3G216900 was an RNA polymeraseⅡtranscription subunit 37E related mediator， HSPA1s helper protein； Seita.4G286000 was CHB gene which coded chitin endonuclease that regulated sugar synthesis and fermentation. Above results revealed the transcriptional regulation of genes related to potassium deficiency stress in foxtail millet， and laid a foundation for the cloning and functional verification of genes related to potassium tolerance in foxtail millet.
In order to screen high-quality quinoa germplasm suitable for Hohhot area， 50 quinoa germplasm resources were selected as experimental materials， and their agronomic characters were comprehensively analyzed and evaluated by correlation analysis， principal component analysis and cluster analysis，through observing their growth period， plant height， main stem diameter， leaf length， leaf width， effective panicles per plant， main branch panicle length， grain weight per plant， 1 000-grain weight and spike color etc. The results showed that there were abundant variations in the agronomic characters of quinoa， and the coefficient of variation ranged from 4.59% to 62.59%； the grain weight per plant was significantly positively correlated with the main stem diameter and effective panicles per plant（P<0.01），and significantly positively correlated with the plant height（P<0.05）； 4 principal components were selected by principal component analysis， and the cumulative contribution rate was 78.518%. Q-type cluster analysis was carried out on 50 quinoa germplasm resources by class average method. When the distance between classes was 5， the tested quinoa germplasm resources were divided into 6 groups. Class Ⅰ germplasm was abundant， class Ⅱ could be used as landscape germplasm resources， class Ⅲ could develop high-quality forage resources. class Ⅳ could continue to be planted for screening tests， class Ⅴ was high-yielding quinoa germplasm， class Ⅵ was dwarf and small quinoa germplasm material. The research results provided theoretical basis and material support for quinoa high-quality germplasm breeding.
Flower bud differentiation is the basis of blueberry flowering and fruiting. Pruning shoots in autumn is one of important measures in greenhouse blueberry cultivation and management， which can effectively regulate flower bud differentiation， but its regulation mechanism is still unclear. To investigate the effect of shoot pruning in autumn on flower bud differentiation and endogenous hormone content in flower bud of blueberry in greenhouse， in autumn， the healthy and erect branches of 5-year-old ‘M7’ blueberry trees were pruned in a sunlight greenhouse， and the unpruned treatment was used as control. On the basis of confirming the difference of flower bud differentiation of axillary buds of new shoots under 2 treatments， the contents of gibberellin （GA3）， auxin （IAA）， abscisic acid （ABA） and zeatin （ZT）， and the ratio of IAA/ABA and ABA/ZT in the axillary buds of unpruned and pruned shoots were analyzed. The results showed that， compared with unpruned shoots （control）， pruning significantly accelerated the process of flower bud differentiation of blueberry in greenhouse， and the number and percentage of flower buds were increased by 4 and 7 times， respectively， the diameter of flower bud increased by 78.26%. The content of GA3 in the upper buds of the pruned shoots decreased by 32.74% during the flowering induction period compared with that in the middle buds of the unpruned shoots， and then increased continuously during the floral organs primordium formation period， and significantly higher than the GA3 content in the upper and central bud in the unpruned shoots. The content of IAA in the upper buds of the pruned shoots was significantly higher than that in the middle buds of the unpruned shoots during flowering induction period， but significantly lower than that in the upper buds of the unpruned shoots， and significantly lower than that in the axillary buds of the middle buds of the unpruned shoots during the formation of the floral organs primordium. ABA was positively correlated with IAA during flowering induction of axillary buds in the upper buds of new shoots after pruning， and the ratio of ABA/ZT increased significantly at first and was significantly higher than that in the middle buds of unpruned shoots. The ratio of IAA/ABA was higher in the formation of floral primordium in the upper buds of pruned shoots than that in the middle buds of unpruned shoots. The shoot pruning in autumn could induce the flower bud differentiation and accelerate the flower bud differentiation of blueberry by decreasing the content of GA3 and ZT， increasing the content of IAA and maintaining high ratio of IAA/ABA. Above results provided a theoretical basis and technical support for exploring the mechanism of shoot pruning on the flower bud differentiation of blueberry.
The application of lactic acid bacteria in food， medicine and other industry depend on their antibacterial activities. To improve antibacterial activity by optimizing the co-cultural conditions of different lactic acid bacteria， the antibacterial activity of Lactobacillus casei NA-2 was determined by double agar diffusion method using Escherichia coli K88 as indicator bacteria， and the culture system was supplemented with Lactobacillus rhamnosus LGG in order to monitor any changes in antibacterial activity. The co-culture conditions of L. casei NA-2 and L. rhamnosus LGG including inoculation ratio， culture temperature， time， aerobic， carbon and nitrogen sources and pH were optimized by single factor test. The total viable cell counts and lactic acid contents of L. casei NA-2 and L. rhamnosus LGG were detected by quantitative real-time PCR method and high performance liquid chromatography， respectively. The results showed that the antibacterial activity was significantly increased after L. rhamnose LGG was added into L. casei NA-2 for co-culture. By comparing L. casei NA-2 pure culture with co-culture without optimization in optimal co-culture conditions， it revealed increases in antibacterial activity of 20.7% and 11.0% and lactic acid production of 15.2% and 7.3%， respectively. The overal viable cell counts decreased from 2.74×108 to 1.57×108 CFU·mL-1 after co-culture conditions optimized， but the proportion of L. casei NA-2 increased from 7.0% to 65.6%. Above results provided data support for further research and application of lactic acid bacteria co-culture system.
Aming at the problems of poor rhizome soil separation and high damage rate in mechanized harvesting of Allium chinense， a new type of Allium chinense harvester was designed， which was mainly composed of digging shovel， swinging sieve， nail roll， throwing roll， buffer laying device. This paper studied the working mechanism of “opposite roller crushing soil + squeeze-brushing separation” of the Allium chinense harvester， which was that the soil crushing roller cooperated with the feeding roller to crush the soil at a higher speed， and the feeding roller continuously pushed backward to complete the separation of the rhizome soil of the Allium chinense； the main factors affecting the harvesting effect of the Allium chinense were analyzed and their value range was determined. A quadratic rotation orthogonal combination experiment was conducted using the forward speed of the machine， the speed difference of the opposite roller， and the rotation radius of the soil crushing roller as experimental factors， and the rhizome soil separation rate and rhizome damage rate as evaluation indicators. This article established a regression model between experimental factors and evaluation indicators， analyzed the impact of experimental factors on evaluation indicators， and optimized working parameters. The results showed that at forward speed of 0.38 m·s-1 and speed difference of 46.02 r·min-1， When the rotation radius of the soil crushing roller was 48.72 mm， the rhizome soil separation rate was 89.30% and the rhizome damage rate was 1.73%. And verification tests were conducted under the same conditions， with rhizome soil separation rate of 88.5% and rhizome damage rate of 1.78%. The machinery meets the requirements for harvesting Allium chinense， and the results provided reference for the research of rhizome soil separation technology and equipment for mechanized harvesting of Allium chinense.
Aiming at the problems of poor adaptability and difficult seed cleaning of soybean seed metering device for plot breeding of soybean， a double swing plate type seed metering device for plot breeding of soybean was designed to improve variety adaptation and seed cleaning through the detachable hole block and seed cleaning plate. The seed metering process was simulated， and the secondary universal rotary combination test was designed to optimize with the hole diameter and swing frequency as test factors and the single grain rate， multiple grain rate and empty grain rate as test indicators. The optimization results was obtained as： the hole diameter was 9~10 mm， the swing frequency was 0.5~1.2 Hz， the single particle rate was more than 60%， the multiple particle rate was less than 30%， and the empty particle rate was less than 15%. Taking the hole diameter of 10 mm and the swing frequency of 1.0 Hz as the test parameters， the bench test and field test were carried out， and the qualification index， replanting index and missed seeding index of the metering device were 75.5%， 16.9%， 7.6% and 71.4%， 18.8% and 9.8% respectively， which were basically consistent with the optimization results. The experiment results showed that the seed metering device can meet the agronomic requirements of plot sowing， and provided a theoretical and reference basis for the design of soybean plot precision seeder.
In order to construct a hyperspectral monitoring model of nitrogen content in the canopy of multiple varieties of millet， the hyperspectral reflectance and leaf nitrogen content of millet in the whole growth stage of millet were obtained by setting up different nitrogen levels and field experiments of multiple varieties of millet. The data of hyperspectral reflectance were preprocessed by convolution smoothing and first derivative transformation. The correlation between hyperspectral data and leaf nitrogen content of millet was analyzed. Nitrogen sensitive bands， vegetation index and hyperspectral characteristic parameters of millet at different and whole growth stages were screened by successive projections algorithm （SPA） and correlation analysis between spectral data and nitrogen content. The partial least square regression （PLSR） estimation model of nitrogen content in millet canopy was established by combining the 3 combinations. The results showed that the optimal estimation models of different growth periods were different. At jointing stage，the model based on sensitive band，vegetation index and hyperspectral characteristic parameters had the highest accuracy. At heading stage， the model based on sensitive band， vegetation index model had the highest accuracy. At pustulation stage， the model based on vegetation index and hyperspectral characteristic parameter model had the highest accuracy. At mature stage， the model based on sensitive band， and vegetation index model had the highest accuracy. In the whole growth period， the model based on sensitive bands and vegetation index had the highest accuracy. The multi-input level synthesis model could make full use of the spectral information to effectively improve the prediction accuracy and stability of the model， and the model based on sensitive band and vegetation index performs had best effect， which the R2 of prediction set was more than 0.82， root-mean-square error （RMSE） was less than 0.119， and relative predicted deviation （RPD） was greater than 2.1. Above results provided theoretical basis and technical support for hyperspectral remote sensing to diagnose nitrogen surplus and deficiency and fertilization decision of millet in the whole growth period.
To investigate the effects of microbial agent on tomato yield， disease incidence， soil physicochemical properties and microbial community structure， no microbial agent was as control （CK）， and Bacillus subtilis was applied with 1 （T1）， 2 （T2） and 3 （T3） times in 1~3 months after tomato transplanting. The incidence and yield of tomato plants and soil physicochemical properties and microbial community structure under different treatments were determined. The results showed that， compared with CK， the yield of T1， T2 and T3 treatments significantly increased by 16.60%， 39.58% and 29.43%， and the incidence of gray mold， leaf mold and late blight significantly reduced. Alpha diversity indices showed that Chao and Shannon indices of soil bacteria significantly increased in T1， T2 and T3 treatments； Chao and Shannon indices of soil fungi significantly decreased in T1， T2 and T3 treatments， which indicated that the addition of microbial agent increased the diversity and richness of bacterial communities and decreased the diversity and richness of fungal communities. In addition， the relative abundance of Actinobacteria， Bacteroidetes， Gemmatimonadetes， Firmicutes， Patescibacteria in bacterial and Mortierellomycota， Basidiomycota， Chytridiomycota， Olpidiomycota and Calcarisporiellomycota in fungi were increased with the increase of the number of microbial agents， while the relative abundance of Chloroflexi， Acidobacteria in bacterial and Ascomycota in fungi were decreased. Redundancy analysis （RDA） showed that the soil organic matter， total nitrogen， alkaline nitrogen， effective phosphorus， and fast-acting potassium were more correlated with bacterial community structure， and soil organic matter content， total potassium， effective phosphorus， fast-acting potassium， pH， and electrical conductivity were more correlated with fungal communities. In conclusion， the applications of microbial agent could significantly reduce the incidence of diseases， increase the yield of tomatoes in facilities， improve the microbial community structure in the soil， and regulate the soil microbial community toward healthy direction.
In order to understand colistin resistance genes carried by Escherichia coli， screen sensitive plant drugs， and solve the dilemma of multiple drug resistance and no drug option in animal clinic， the resistance genes of Escherichia coli were identified by 16S rRNA sequencing and PCR. The antimicrobial susceptibility of 78 antibiotics were detected， and the bacteriostatic and bactericidal effects of 4 kinds of natural plant extracts （palmatine， berberine， baicalin and macleaya cordata） were tested. The results showed that 145 strains of E.coli were isolated and identified from intestinal tract of swine clinical diarrhea cases in 2021 （from January to December） and 2022 （from January to June）， and a clinical strain carrying colistin resistance genes （mcr-4，mcr-5） and β-lactamases blaTEM and AmpC was identified， which named HN2149. The antimicrobial susceptibility of 78 antibiotics showed that the HN2149 strains was sensitive to cefepime， cefodizime， fosfomycin， cefixime， meropenem， cefoxitin， cefazolin， cefoperazone， cefotaxime， ceftazidime， cefuroxime， ceftriaxone， aztreonam， piperacillin-tazobactam， ticacillin/clavulanic acid， cefoperazone sulbactam， ceftazidime/clavulanic acid， cefotaxime/clavulanic acid， ceftizoxime， cefmetazole， cefetamet， and was resistant to 57 antibiotics. The drug sensitivity of 4 plant extracts showed that the macleaya cordata had the best bacteriostatic and bactericidal effect on HN2149 strain， while the other 3 extracts had no effects on HN2149 strain. Above results provided reference for the prevention and control of swine colibacillosis.
The linkage regulation of extracytoplasmic function （ECF） sigma factors and two-component system （TCS） play essential roles for bacteria adaptation to various environment and stress condition. In order to study the ECF-sig25 gene in Streptomycesavermitilis and explore the regulatory pathway of Sig25， the response of Sig25 to stress was detected by spore spot test， its influence on morphological differentiation was analyzed by plate culture， and the target gene of Sig25 was verified by bioinformatics and RT-qPCR. The results showed that TCS gene smrAB was located upstream of ECF-sig25， and the phosphorylation of SmrA depended solely on SmrB. Stress tests showed that Sig25 responded to high pH， osmotic stress， SDS and heat stress， but not to oxidative stress， acid stress and EDTA stress. Bioinformatic prediction， RT-qPCR and electrophoretic mobility shift assay （EMSA） results revealed that Sig25 directly regulated transcription of whiG， SAV3434， SAV4621， SAV5010， SAV6537， gdhA1， glnA2 and amtB1， which were involved in morphological development， methyl group supply， DNA replication， signal transduction， secondary metabolism and nitrogen metabolism. The plate culture showed that deletion of sig25 had no effect on morphological developmentin of S. avermitilis.
Pre-prepared poultry meat dishes plays an important role in improving people’s living standards， rural revitalization， standardization of the catering industry and high-quality development of the poultry industry. However， there are many unfavorable factors affecting the quality and safety during the production and consumption processes of pre-prepared poultry meat dishes. The factors that affect quality and safety in various aspects such as poultry breeding and slaughtering， processing and packaging， storage and transportation， sales and consumption of pre-prepared poultry meat dishes were analyzed. According to the establishment of poultry ecological breeding environment and input management， the construction of poultry slaughtering site and production management， the optimization of pre-prepared poultry meat dishes processing technology and the implementation of green label system， the selection of packaging materials and the application of packaging technology， the establishment of scientific management system and the application of information technology in storage and transportation， the improvement of sales management system and scientific guidance to consumers and so on， corresponding optimization strategies were proposed aiming to promote the improvements of quality and safety and the development of the pre-prepared poultry meat dishes industry， which provided a theoretical basis and model reference for rural revitalization， the solution of the problem of ‘agriculture， rural areas and farmers’， the development of poultry industry and catering industry， the needs of the people for a better life and the construction of ecological civilization.
In order to quantitatively evaluate the comprehensive characteristics of rice quality， the head yield， chalkiness， transparency， alkali spreading value，gel consistency，and amylose content were utilized as the indicators for rice quality evaluation， according to the industry standards of cooking rice variety quality， based on the quality data gathered from regional trials for mid-season indica rice and mid-season japonica rice in Anhui province from 2008 to 2021. The methods of classification assignment and linear weighted summation as well as computer numerical simulations were employed to clarify weight coefficients for each evaluation index of rice quality and construst the rice quality index （IRQ）for mid-season indica rice （IRQ1） and mid-season japonica rice （IRQ2）， and eventually determined the comprehensive rice quality evaluation method for mid-season indica rice and mid-season japonica rice. The results showed that the weight coefficients of the quality evaluation index for mid-season indica rice were 0.20 for head yield， 0.26 for chalkiness， 0.06 for transparency， 0.22 for alkali spreading value， 0.10 for gel consistency， and 0.16 for amylose content. In contrast，the weight coefficients mid-season japonica rice were 0.23， 0.28， 0.10， 0.08， 0.15， 0.16， respectively， among which chalkiness was the main factor affecting the quality of mid-season rice. For mid-season indica rice， the thresholds for rice quality index corresponded to the first， second， and third-grade high-quality rice as well as ordinary rice were： IRQ1≥3.94， 3.94> IRQ1≥3.47， 3.47> IRQ1≥3.17 and IRQ1<3.17. Whereas for mid-season japonica rice the thresholds for the quality index corresponded to the first， second， and third-grade high-quality rice as well as ordinary rice were： IRQ2≥3.82， 3.82> IRQ2≥3.33， 3.33> IRQ2≥3.04 and IRQ2<3.04. After conducting a thorough verification， this comprehensive evaluation method for mid-season Indica and Japonica rice quality yielded an average accuracy of 81.4% and 80.0% for multi variety sample testing in Anhui province. Furthermore，accuracy were 85.7% and 92.9% for a single variety of rice. For multi-variety sample testing in other provinces， accuracy rates consistently exceeded 80% which proved that this method could be used for quantitative evaluation of the comprehensive quality of mid-season indica and japonica rice in diferent areas.
To optimize the optimal formula of red matsutake beef sauce， the response surface methodology was used to study the effects of the additions of red matsutake， soybean paste， millet pepper and potato starch on quality of red matsutake beef sauce. The shelf life was predicted by Arrhenius equation and kinetic equation based on peroxide value and acid value. The results showed that the optimal formula of red matsutake beef sauce obtained by response surface methodology was followed with 15.0% red matsutake， 37.4% soybean paste， 13.4% millet pepper， and 8.3% potato starch， the sensory score of red matsutake beef sauce was 91.23 under these conditions. Under different ambient temperatures （25， 37 and 45 ℃）， the total viable count， peroxide value and acid value of red matsutake beef sauce were positively correlated with storage time， while the sensory score showed a downward trend. The shelf life of red matsutake beef sauce was predicted to be 147 d at 25 ℃ based on peroxide value， and was 103 d at 25 ℃ based on acid value， so the shelf life model constructed based on acid value was more reliable. Above results provided theoretical support for high value utilization and shelf life prediction of red matsutake.
Kitchen waste can produce biogas through anaerobic digestion， achieving its reduction and recycling of renewable energy， and promote the development of the industry towards the “dual carbon” goal. The main hydrolytic acid-producing bacteria and various nutritive methanogens in the anaerobic digestion of food waste were summarized， and the influence of environmental factors on anaerobic digestion of kitchen waste in the process of bogging and the relationship between them and microbial activity were emphatically discussed. At the same time， based on the study on the whole life cycle of anaerobic digestion of kitchen waste， the impact of biogas production and application on the environment was analyzed. Finally， in view of the low efficiency of anaerobic digestion of kitchen waste， the prospect of system optimization was carried out to achieve the purpose of efficient recycling and high-value utilization of kitchen waste， so as to realize the transformation of energy structure and promote the green and low-carbon development of the city.
Microorganism induced carbonate precipitation （MICP） can fill soil pores， reduce water evaporation and enhance the wind erosion resistance of aeolian sandy soil. Its effect of wind prevention and sand fixation has been confirmed， but its impact on the leaf characteristics and growth physiological process of sandy plants is not clear. In order to reveal the effect of micro-organism-induced calcium carbonate precipitation and sand fixation on the leaf characteristics and photosynthetic physiological characteristics of desert plants， the indoor pot experiment was carried out with 4 kinds of desert plants， namely， Agriophyllum squarostrum， Astragalus laxmannii， Caragana korshinskii and Corethrodendron fruticosum as the research objects. The leaf characteristics and physiological characteristics of desert plants with high （H）， middle （M） and low （L） microbial agent levels and top （T）， centre （C） and bottom （B） of consolidation layer were compared and analyzed. The results were followed. ① Microorganism induced carbonate was distributed among the aeolian sand particles， and it was cubic， rhombic， spherical and amorphous， which could cement the aeolian sand particles. ② The microbial agent treatment significantly increased the soil organic matter and calcium carbonate contents of 4 types of sandy plants. When high level of microbial agents were applied， the soil organic matter and calcium carbonate contents of consolidation B layer treatment group were significantly higher than those of the other treatment groups. The organic matter content in the soil of A. laxmannii increased the most， reaching to 90.19%， while the calcium carbonate content in the soil of C. korshinskii increased the most， reaching to 41.47%. ③ The specific leaf area of A. squarostrum in high level microbial agent treatment group was significantly higher than those in other treatment groups， average increase of 0.98%； and the dry matter contents of A. squarostrum and A. laxmannii in low level microbial agent treatment group were significantly higher than those in other treatment groups， with an average increase of 34.11% and 24.18%， respectively. In the consolidation layer C treatment group， the specific leaf areas of A. squarostrum， A. laxmannii and C. korshinskii were significantly lower than those in the other treatment groups. ④ The content of chlorophyll in leaves of A. squarostrum， A. laxmannii and C. korshinskii under the high level microbial agent treatment group were significantly higher than those in the other treatment groups， with an average increase of 9.01%， 12.97%， and 31.77%， respectively； and the maximum net photosynthetic rates of the middle level microbial agent treatment group were significantly higher than those in the other treatment groups， with an average increase of 55.70%， 48.39% and 13.24%， respectively. In conclusion， the application of microbial agent could increase the contents of soil organic matter and calcium carbonate， provided sufficient nutrients for plant growth. Therefore， the photosynthetic physiological characteristics of A. membranaceus， A. obliquus， and C. caragana under the microbial agent treatment groups were significantly higher than those of control. However， the response of plant leaf traits to soil organic matter and calcium carbonate content was not significant. MICP could promote the leaf traits and photosynthetic physiological characteristics of A. squarostrum under the middle level microbial agent treatment and the high level treatment of A. laxmannii and C. korshinskii， but could inhibit the leaf traits and physiological characteristics of C. fruticosum. Above results provided theoretical basis and scientific support for enriching and improving the technology of microbial induced calcium carbonate precipitation and sand fixation.
In order to explore the remediation technology of biochar and rape seedlings for heavy metal cadmium （Cd） contamination of soil in the southern border area，the yellow rape， black rape and Indian mustard （Brassica juncea） were used as test materials， the mass fraction of biochar addition was set as 0% （T0）， 2% （T2）， 4% （T4）， 6% （T6） and 8% （T8）， respectively. The effects of biochar addition on the growth and Cd accumulation of rapeseed seedlings under cadmium （Cd） stress were elucidated by measuring and analyzing the soil physicochemical properties and Cd morphology， seedling biomass and enrichment transport of each site in different treatments. The results showed that the pH， organic matter content and oilseed rape biomass （dry weight） in the soil increased significantly with the increase of biochar addition； meanwhile， the content of the more active exchangeable Cd gradually decreased， and the content of carbonate-bound Cd， Fe-Mn oxide-bound Cd， organic matter and sulfide Cd， which were not easily absorbed by the crop， gradually increased.When the soil Cd content was certain， the Cd activity index decreased gradually， and the passivation effect of T8 treatment was the most significant. Biochar effectively reduced the root enrichment coefficient and above-ground transport coefficient of rapeseed， and the best effect was achieved with 8% biochar application. The best response effects of pH， organic matter content， rapeseed biomass， Cd morphology changes and root enrichment coefficient and above-ground transport coefficient in yellow rape soil were observed under different biochar treatments. Overall， the best passivation effect and growth characteristics of rapeseed were selected for 8% biochar application， and yellow rape showed the best response to biochar treatment. By adding biochar， the heavy metal Cd was effectively mitigated on the growth of rape seedlings in South Xinjiang region， which provided technical and theoretical support for oilseed rape cultivation in South Xinjiang region.
In order to explore the effects of nitrogen reduction on the characteristic of dry matter accumulation and yield of cotton， 4 treatments were set up， including conventional nitrogen treatment （N1， nitrogen application rate 345 kg·hm-2）， 20% nitrogen reduction treatment （N2， nitrogen application rate 276 kg·hm-2）， 20% nitrogen reduction combined with 10% organic fertilizer treatment （N3， nitrogen application rate 276 kg·hm-2， the ratio of chemical fertilizer and organic fertilizer was 9∶1） and no nitrogen treatment （N4）， to analyze the responses of cotton dry matter accumulation characteristic parameters， yield and nutrient content to different nitrogen reduction treatments. The results showed that compared with N1 treatment， N2 and N3 treatments significantly increased the dry matter distribution ratio of reproductive organs at catkins period by 10.29% and 15.10%， shortened the dry matter accumulation time by 10.97% and 13.27%， and increased the dry matter accumulation fast growth period by 11.76% and 90.04%， accelerating the growth process of cotton. N4 treatment reduced the average rate of dry matter accumulation by 45.30%， and delayed the appearance time of the maximum rate of dry matter accumulation. The yield and economic benefit of seed cotton in 2 years were the highest in N3 treatment， which were 3 496.87 kg·hm-2 and 22 956.64 yuan， respectively. Therefore， N3 treatment，namely 20% nitrogen reduction combined with 10% manure， was a nitrogen reduction measure with high yield， fertilizer saving and the best economic benefits in northern Jiangxi cotton region. Above results provided guidance for reducing the amount of nitrogen fertilizer input in cotton growing area of northern Jiangxi.
In order to explore the effects of different application methods of biofertilizer FBR1 （ Bacillus subtilis ） on the growth and yield of peanut， ‘Huayu 9113’ was used as the test material. Taking without seed coating agent without bacterial fertilizer was used as control 1（CK1）， with seed coating agent 1 250 mL·hm-2 without bacterial fertilizer as control 2（CK2）， 4 treatments were set up， including spread 15 kg·hm-2 bacterial powder on the surface and sow seeds without seed coating agent after ridging（T1），without seed coating agent after sowing applied with 15 kg·hm-2 bacterial powder in the hole（T2）， with 7.5 L·hm-2 bacterial liquid for seed dressing（T3）and with 1 250 mL·hm-2 seed coating agent after coating with 15 kg·hm-2 fungus powder（T4）， and peanut plant development， dry matter distribution and yield of each treatment were analyzed. The results showed that T1 treatment could promote the growth of peanut， and increase the pod weight per plant and total biological dry weight. T3 treatment reduced the seedling rate. T4 treatment not only reduced the main stem height， but also reduced the number of harvested holes. The pods and kernels of T1 and T3 treatments were higher than those of CK1，which increased by 84.93， 34.97 and 32.48， 5.00 kg·hm-2， respectively. The pods and kernels of T2 treatment decreased by 84.93 and 82.43 kg·hm-2 compared with CK1. The pod and seed yield of T4 treatment decreased by 92.42 and 32.47 kg·hm-2 compared with CK2， but the increase and decrease were not significant. In summary， considering the diversity of soil conditions in Weihai， we recommended the method of sowing seeds without seed coating agent after surface spreading 15 kg·hm-2 of fungal powder and applying FBR1 biofertilizer according to local conditions on the premise of a good demonstration trial. Above results provided a reference basis for its application in peanut production.
In order to further clarify the effect of environmental factors on the chlorine content of tobacco leaves in tobacco-growing areas and their possible influencing paths， the tobacco leaves， corresponding soil and irrigation water samples were collected from 7 townships in a tobacco-growing area in Yunnan in 2021. The chlorine content of tobacco leaves in tobacco-growing areas was systematically evaluated and its possible relationship with tobacco-growing soil and irrigation water was discussed. The results showed that there was a risk of excessive chlorine content in tobacco leaves， irrigation water and soil in this tobacco planting area. Among them， 28.79% of the chlorine content in tobacco leaves exceeded the standard of high-quality tobacco leaves. Mantel-Test analysis showed that the chlorine content of tobacco leaves was negatively correlated with the overall quality of tobacco leaves， and was closely related to the main physical and chemical properties of soil and the chlorine content of irrigation water. The structural equation model （SEM） analysis showed that the chlorine content of irrigation water had a very significant direct positive effect on the chlorine content of tobacco leaves （ the influence coefficient was 0.459）， and had a significant direct negative effect on the chemical properties of soil （the influence coefficient was 0.225）， while the physical properties of soil also had a very significant positive effect on chemical properties （the influence coefficient was 0.370）. In summary， there was a high risk of chlorine content exceeding the standard in this tobacco planting area. The chlorine content of irrigation water and soil physical properties might be important factors， which could cause the chlorine content of tobacco leaves to exceed the standard by affecting soil chemical properties and soil chlorine content， and ultimately reduce the quality of tobacco leaves.
Concanavalin A （Con A） is mainly found in jack bean， and it is a plant lectin that can specifically bind to polysaccharides， glycoproteins and other substances. Con A has anti-nutritional and anti-pest effects， which is an important part of plant self-protection， and also the main cause of food poisoning and allergic reactions caused by eating legumes. Therefore， the detection of Con A is of great significance for legume vegetable breeding and food safety assessment. The research progress of novel rapid detection technologies for Con A was introduced in detail， including nanomaterial based biosensor， immune sensing technology， sugar sensing technology and aptamer sensing technology. Biosensors based on nanomaterials had high accuracy but lack biological specificity； the immune sensing technology had improved the detection speed of the traditional immune method but still had the problem of insufficient signal repeatability； sugar sensing technology had greatly improved the specificity and detection accuracy of hemagglutination method， but it could not distinguish lectins with the same sugar specificity. Aptamers based detection technology had excellent detection accuracy， specificity and repeatability， and unnatural aptamers could be obtained through chemical modification to further enhance the specificity， which should be the development trend of rapid detection of Con A in the future.
In order to optimize the detection method of Chinese chestnut yellow crinkle and clarify the resistance of 10 chestnut varieties， the resistance evaluation was carried out by optimizing the content of nested PCR primers and annealing temperature， combined with phytoplasma detection rate and field disease index. The results showed that the detection rate of chestnut phytoplasma was the most stable when the primer addition amount was 1.0 μL and the annealing temperature was 54 ℃. After 400 d of grafting， phytoplasmas were detected in all the tested chestnut varieties. Among them， the detection rate of phytoplasma in the leaves of ‘Yanshan Zaofeng Yabian’ was the highest and the incidence was the most serious， while the detection rate of phytoplasma in the leaves of ‘Yanli’ was the lowest and the incidence was the lightest. The correlation analysis showed that the detection rate of phytoplasma was significantly positively correlated with the field disease index， the correlation coefficient was 0.907， and the linear regression equation was Y=0.276X+1.610. According to 2 evaluation methods， the tested chestnut varieties were divided into high resistance， medium resistance and high sensitivity. Among them，‘Yanqiu’‘Yanzi’‘Yanlong’and‘Yanli’were high resistance varieties， and ‘Yanshan Zaofeng Yabian’was high sensitivity varieties. The resistance difference of 10 chestnut varieties to Chinese chestnut yellow crinkle was preliminarily clarified， which provided basic data for the selection of resistant varieties.
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