In order to clarify the function of the protein phosphatase 2C gene GmPP2C72 in salt stress response and its salt-tolerance molecular mechanism,bioinformatics analysis of GmPP2C72 protein was conducted, GmPP2C72 gene was cloned to construct the overexpression vector,and then was transferred into Lotus japonicus using the cotyledon node genetic transformation method mediated by Agrobacterium tumefaciens.Finally,the phenotype,physiological indicators and the expression levels of salt tolerance related genes of transgenic plants were analyzed under salt stress condition.The results showed that GmPP2C72 gene contained an open reading frame of 1 206 bp,encoding 401 amino acids,and the encoded protein belonged to the member of the class A subfamily of PP2C family.GmPP2C72 gene did not exhibit tissue expression specificity,it was expressed in various tissues of soybean,and the expression of this gene was induced by salt stress.The overexpression vector of GmPP2C72 gene was successfully constructed.GmPP2C72 gene was successfully transferred into Lotus japonicus,and three transgenic lines with GmPP2C72 gene were successfully obtained.Compared with wild type,the three transgenic lines maintained better growth state,with significantly higher contents of chlorophyll and proline and lower relative plasma membrane permeability and malondialdehyde content in leaves of Lotus japonicus under salt stress.In addition,the expression levels of four key salt tolerance related genes,LjLEA, LjCOR,LjRD29B,and LjP5CS were significantly higher compared with wild type.Overall,the overexpression of GmPP2C72 gene enhances the salt tolerance of Lotus japonicus by reducing the degree of membrane lipid peroxidation and the permeability of the plasma membrane,increasing the contents of chlorophyll and proline in the leaves,and enhancing the expression levels of salt tolerance related genes.

Cinnamic acid 4-hydroxylase (C4H),a key enzyme in the flavonoid synthesis pathway,plays a crucial role in plant stress resistance.To clarify the bioinformatic functions of the C4H gene family in three medicinal liquorice species (Glycyrrhiza uralensis Fisch.,Glycyrrhiza inflata Bat.,and Glycyrrhiza glabra L.),investigate their expression characteristics under abiotic stress,as well as their relationship with the synthesis and accumulation of liquiritin,we used bioinformatics methods to analyze the C4H gene family members,and combined transcriptome data and RT-qPCR validation to understand their expression under abiotic stress and their relationship with liquiritin content.Results showed that a total of 11 C4H genes were identified in the whole genomes of the three medicinal liquorice species and were named GuC4H1—3,GiC4H1—3,and GgC4H1—5,respectively.These genes were distributed on 2 chromosomes in G.uralensis and G.inflata and on 3 chromosomes in G.glabra.Although the gene members differed in physicochemical properties such as the number of amino acids and isoelectric points,all of them were predicted to be localized in the endoplasmic reticulum and contain a C-terminal heme-binding domain (PFGVGRRSCPG).Expression pattern analysis indicated that the 11 C4H genes were expressed in different tissues of the three medicinal liquorice species,and abiotic stress significantly induced the upregulation of C4H gene expression in the underground parts.Among them,the expression of GgC4H5 was the highest under salt stress for 24 h,which was 1.68 times that of the control group (24 h);the expression of GuC4H3 was the highest under drought stress for 2 h,which was 3.03 times that of the control group (2 h).In addition,moderate abiotic stress significantly increased the liquiritin content in the underground parts of the three liquorice species.Under NaCl stress for 2 h,the increase in liquiritin content in G.inflata was the most significant,which was 2.92 times that of the control group (2 h);under PEG stress for 24 h,the increase in liquiritin content in G.glabra was the most significant,which was 2.31 times that of the control group (24 h).GgC4H5 showed a similar expression trend to liquiritin content under salt stress,while GuC4H2,GuC4H3,GiC4H2,and GiC4H3 showed a similar expression trend to liquiritin content under drought stress.Therefore,these genes are likely to be the key genes involved in the response to abiotic stress and liquiritin synthesis in the underground parts of the three medicinal liquorice species.

To investigate the physiological regulatory role of salicylic acid(SA)in alleviating saline-alkali stress in kidney bean seedlings and to provide a basis for stress-resistant cultivation of kidney beans in typical saline-alkali areas of Shanxi Province,kidney beans were used as the test material.A composite saline-alkali stress system with a ratio of NaCl,Na₂SO₄,NaHCO₃,and Na₂CO₃ of 1∶9∶9∶1 was used to simulate saline-alkali stress.Five concentration gradients of 0(CK),20,40,60,and 80 mmol/L were set to screen for the optimal concentration of salt-alkali stress treatment.Subsequently,based on the selected concentration,three SA concentrations(20,40,and 60 μmol/L)were applied simultaneously to study the mitigating effect of SA on kidney bean seedlings under saline-alkali stress.The results indicated that under 40 mmol/L salt-alkali stress,the growth of red kidney beans was significantly inhibited but did not reach lethal or severe stress levels,making it the optimal salt-alkali stress concentration.Stress at this concentration induced oxidative damage in early seedlings,inhibited nutrient absorption and translocation,increased the activities of arginine decarboxylase(ADC)and ornithine decarboxylase(ODC),and led to excessive accumulation of putrescine(Put).Under 40 mmol/L saline-alkali stress,exogenous application of 40 μmol/L SA reduced malondialdehyde(MDA)content in leaves and roots by 37.63% and 39.76%,respectively;hydrogen peroxide(H₂O₂)content by 38.71% and 21.13%,respectively;and superoxide anion(O₂^-)content by 40.00% and 52.17%,respectively.Root activity increased by 56.14%.The Na content in both leaves and roots significantly decreased,while the contents of K,Cu,Ca,and Fe significantly increased.Furthermore,exogenous application of 40 μmol/L SA reduced the activities of ADC and ODC,increased the activity of S-adenosylmethionine decarboxylase(SAMDC),and promoted the conversion of Put to spermidine(Spd)and spermine(Spm),thereby enhancing the plant's antioxidant capacity and ion homeostasis regulation.In conclusion,exogenous salicylic acid can effectively alleviate the physiological damage caused by composite saline-alkali stress in kidney bean seedlings by activating the antioxidant system,optimizing polyamine metabolism,and promoting the absorption and distribution of mineral elements.

In order to investigate the effects of different concentrations of γ-aminobutyric acid(GABA)on the nutritional quality and antioxidant activity of cherry tomatoes,cherry tomatoes were used as experimental materials.Foliar spraying of GABA solutions with different concentrations(0,5,10,20,and 40 mmol/L,denoted as CK,G5,G10,G20,and G40,respectively)was initiated at 15 days after the anthesis of the 3rd inflorescence.It aimed to explore the impacts of exogenous GABA application on the nutritional quality,endogenous GABA content,and antioxidant activity-related indicators of cherry tomatoes.The results showed that exogenous GABA treatment could significantly improve the nutritional quality and antioxidant capacity of cherry tomatoes.With the increase in treatment concentration,the contents of soluble sugar,total phenols,and total flavonoids,as well as the sugar-acid ratio,increased continuously.Nutritional quality indicators such as vitamin C content,soluble sugar content,and sugar-acid ratio all reached their maximum values under the G40 treatment.The contents of total phenols and total flavonoids in the G40 treatment were significantly higher than those in other treatments except G20,increasing by 24.26% and 91.75% compared with CK,respectively.The lycopene content of cherry tomatoes under the G40 treatment was the highest,which was significantly 85.96% higher than that of CK.The endogenous GABA content first increased and then decreased with the elevation of treatment concentration,reaching the maximum value under the G20 treatment,which was significantly 101.85% higher than that of the control.However,there was no significant difference in endogenous GABA content between the G20 and G40 treatments.Both DPPH free radical scavenging activity and FRAP antioxidant capacity were synchronously enhanced,and both reached their maximum values under the G40 treatment,which were significantly higher than those of CK.Correlation analysis indicated that the antioxidant capacity of cherry tomatoes was extremely significantly positively correlated with total phenols,total flavonoids,and lycopene.In conclusion,exogenous GABA(G40 treatment)can serve as a green and efficient strategy to enhance the nutritional quality and antioxidant activity of cherry tomato fruits.

The mechanism of the effect of phosphorus application rate on the growth,yield formation and phosphorus fertilizer utilization rate of high-yield maize in Xinjiang under the condition of drip irrigation and fertilizer integration was clarified,in order to provide a theoretical basis for the high and stable yield of maize in Xinjiang and the green sustainability of fertilizer reduction and efficiency increase.The experiment was carried out in the maize high-yield demonstration base of Qitai Farm in Xinjiang from 2023 to 2024.Under the condition of drip irrigation and fertilizer integration,six phosphorus application levels were set up:no phosphorus fertilizer(P₀),pure phosphorus 60 kg/ha (P₆₀),90 kg/ha(P₉₀),120 kg/ha (P₁₂₀),150 kg/ha (P₁₅₀)and 180 kg/ha(P₁₈₀,CK).The changes of leaf area index(LAI),photosynthetic potential(LAD),dry matter accumulation,harvest index(HI),ear traits,yield and yield components of maize with water and fertilizer integration of dense planting drip irrigation were analyzed,and the effect of phosphorus application rate on yield and phosphorus fertilizer utilization rate of maize with dense planting drip irrigation in Xinjiang was clarified.The results showed that under the condition of drip fertigation and phosphorus application,the maize yield increased first and then tended to be stable with the increase of phosphorus application in the two years,and the yield was the highest(18.79—20.94 t/ha)at P₁₂₀ treatment.The amount of phosphorus application significantly affected the 1000-grain weight and grain number per ear of maize.The amount of phosphorus application mainly affected the length of maize ear bald tip.Compared with P₁₅₀ and P₁₈₀ treatments,the difference of ear bald tip length was not significant.During the critical growth period of corn,LAI showed a trend of first increasing and then stabilizing with increasing phosphorus fertilizer application rates.The LAI of maize under P₁₂₀ treatment at silking stage was 7.56—7.81,which was not significantly different from P₁₅₀ and P₁₈₀ treatments,but was significantly reduced by 21.54% under P₀ compared with P₁₂₀.In addition,the dry matter accumulation before and after anthesis of maize treated with P₁₂₀ was not significantly different from that of P₁₅₀ and P₁₈₀ treatments,which was 37.91% and 93.88% higher than that of P₀,respectively.In summary,drip fertigation and phosphorus application significantly affected LAI,LAD,pre-anthesis and post-anthesis dry matter accumulation and HI,shortened bald tip length,increased grain number per spike and 1000-grain weight,and then increased maize yield and phosphorus utilization efficiency,and realized the synergistic improvement of maize yield and phosphorus fertilizer utilization efficiency.

To explore the accumulation characteristics of soil phosphorus and its distribution pattern in the profile after long-term application of different organic fertilizers,a long-term field experiment was conducted to investigate the distribution and migration patterns of phosphorus in the soil profile under continuous application of different amounts of livestock and poultry manure organic fertilizers and sludge compost.The results showed that after 11 consecutive years of application of high amounts(60 t/ha per year)of pig manure,chicken manure and sludge,the phosphorus they brought in could obviously migrate to the 30—60 cm soil layer.The application of medium and high amounts(45,60 t/ha per year)of pig manure,chicken manure organic fertilizers and sludge compost could make the available phosphorus migrate to the 60—90 cm soil layer.After 11 years of application of different types of organic fertilizers,the phosphorus activation coefficient of the plough layer soil showed a significant upward trend,and the difference between high and low application rates reached a significant level.The order of soil phosphorus activation coefficient under different organic fertilizer treatments was:pig manure organic fertilizer treatment>chicken manure organic fertilizer treatment>sludge compost treatment.The content of available phosphorus in the plough layer soil after the application of chicken manure,pig manure organic fertilizer and sludge compost conformed to the linear plus plateau regression model with the phosphorus input.Under the condition of equal phosphorus input of organic fertilizer,the contribution of pig manure and chicken manure organic fertilizer to the available phosphorus in the plough layer soil was significantly higher than that of sludge compost.When the phosphorus input was greater than 7.14 t/ha,the contribution of pig manure organic fertilizer to the available phosphorus in the plough layer soil was significantly higher than that of chicken manure.The total phosphorus and available phosphorus contents in the soil profile were significantly positively correlated with the organic carbon content.In the 0—90 cm profile,soil organic carbon and phosphorus might co-migrate.

This study aims to explore the effects of reduced nitrogen application combined with organic fertilizer on soil carbon and nitrogen contents in the 0—60 cm layer of fragrant pear orchards,as well as the yield and quality of Korla fragrant pears,and to propose the optimal rate of reduced nitrogen application and matching ratio of organic fertilizer.Using 10—12-year-old Korla fragrant pear trees as test materials,a 3-year continuous experiment was carried out.The experiment set up a conventional nitrogen application treatment(denoted as N,with 300 kg/ha of nitrogen applied),three reduced nitrogen application treatments(denoted as N1,N2,N3,which reduced nitrogen by 10%,20%,and 30% respectively compared with the conventional nitrogen application treatment),and two organic fertilizer treatments(denoted as OF1 and OF2,with 22 500,33 750 kg/ha of sheep manure applied respectively).These treatments were combined to form six integrated treatments:N1F1,N2F1,N3F1,N1F2,N2F2,and N3F2.The soil carbon and nitrogen contents,soil carbon-to-nitrogen ratio(C/N),as well as the yield and quality of Korla fragrant pears were determined.The result showed that N1F1,N1F2,N2F2,and N3F2 treatments significantly increased the contents of total soil carbon,soil organic carbon,soil inorganic carbon,soil microbial biomass carbon(SMBC),soil nitrate nitrogen,and soil ammonium nitrogen in the orchard.They also increased the soil C/N ratio,the contents of soluble sugar and vitamin C in pear fruits,decreased the total acid content in fruits,and had no significant effect on pear yield.The N2F1 treatment significantly promoted the contents of soil nitrate nitrogen and ammonium nitrogen but had no significant effect on pear yield or quality.The N3F1 treatment significantly inhibited the contents of soil carbon fractions and pear yield and reduced the soluble sugar content in fruits.Correlation analysis showed that soil nitrate nitrogen,ammonium nitrogen,organic carbon,inorganic carbon,total nitrogen,total carbon,SMBC,and soil microbial biomass nitrogen(SMBN)were significantly or extremely significantly correlated with pear quality;the soil C/N ratio was significantly or extremely significantly negatively correlated with pear yield and quality.Among these factors,soil organic carbon,total nitrogen,nitrate nitrogen,and ammonium nitrogen had more prominent effects on pear yield and quality.Therefore,in subsequent fertilization management,improving the contents of soil organic carbon,total nitrogen,nitrate nitrogen,and ammonium nitrogen and regulating the soil C/N ratio can better increase the yield and improve the fruit quality of Korla fragrant pears.In the management of 10—12-year-old Korla fragrant pear trees,reducing nitrogen application by 20%—30% on the basis of the conventional nitrogen application rate while applying organic fertilizer at 33 750 kg/ha is beneficial.This measure regulates soil carbon and nitrogen contents,improves pear quality,reduces chemical fertilizer input to alleviate soil pollution,and ensures the health of the soil environment.

Establishing a rapid and sensitive molecular detection technology for Pectobacterium parvum and P.versatile will lay a technical foundation for the rapid detection,early diagnosis,as well as the transmission routes and dynamics of potato stem rot.Through the sequence analysis of the specific locus gene 10748 of P.parvum and the specific locus gene 1602 of P.versatile,the Real-time PCR and LAMP primer design software were carried out by using Primer 3 and NEB website primer design software.After specificity validation,reaction condition optimization,and sensitivity validation,primers were screened and sample detection was performed.Quantitative Real-time PCR primers XX3-F/R and DY1-F/R were designed and screened for P.parvum and P.versatile.The sensitivity for detecting DNA in artificially inoculated plant samples reached 10,1 pg/μL,respectively.The sensitivity for detecting gDNA of pathogenic bacteria reached 0.1 pg/μL.Design LAMP primers for P.parvum and P.versatile,with detection sensitivity similar to Quantitative Real-time PCR detection technology.Quantitative Real-time PCR and LAMP detection techniques had been established for the detection of potato aerial stem rot pathogens,such as P.parvum and P.versatile,which can detect potato stems and tubers infected by P.parvum and P.versatile,as well as drosophila carrying bacteria.

In previous research,cytochrome P450 oxidoreductase(POR)was identified as a critical host factor facilitating aflatoxin B1(AFB1)-induced hepatotoxicity through CRISPR/Cas9 library screening.To further elucidate the mechanistic role of POR in AFB1-mediated hepatocellular damage,we designed two single-guide RNAs(sgRNAs)targeting exon 5 of the human POR gene,based on its published sequence,using CRISPR/Cas9 gene-editing technology.These sgRNAs were cloned into the lentiCRISPRv2 vector,which was subsequently packaged into lentivirus and utilized to infect THLE-2 human hepatocytes.Monoclonal cell lines were isolated by limiting dilution,and knockout efficiency was assessed at both the mRNA and protein levels using off-target sequencing,reverse transcription quantitative PCR(RT-qPCR),and Western Blot analysis.The findings indicated that V2-sgRNA-POR-1 successfully knocked down POR expression,resulting in a significant reduction at both the transcriptional and translational levels in the selected monoclonal cells.Further experiments involved treating THLE-2 wild-type cells with varying concentrations of AFB1(100,200,400,800 μmol/L)for durations of 24,48,and 72 hours.CCK-8 cell viability assays demonstrated that AFB1 toxicity to hepatocytes was significantly dependent on both concentration and exposure time,with an optimal exposure condition identified at 200 μmol/L for 48 hours[IC₅₀(48 h)=(200.55±44.49)μmol/L].Under these conditions,POR knockout cell lines exhibited marked resistance to AFB1-induced cytotoxicity,with significantly higher cell viability than wild-type cells.These findings suggest that POR plays a critical role in facilitating AFB1-mediated hepatocyte toxicity,and that POR knockout substantially enhances cellular resistance to AFB1.

Based on quantitative trait locus(QTL)mapping of grain weight and grain shape-related traits in a backcross inbred line(BIL)population derived from the cross between indica rice variety Changhui 891 and japonica rice variety 02428,this study provided valuable genetic resources for elucidating the genetic basis of grain development and molecular breeding for high yield and quality in rice.A high-density genetic map was used to conduct QTL analysis for thousand-grain weight,grain length,grain width,grain thickness,and length-width ratio under two environments.Transcriptome data of developing grains at 5,10,and 15 days after flowering from both parents were integrated to analyze candidate genes within QTL regions.Frequency distribution indicated that grain weight and shape traits in the BIL population exhibited typical quantitative characteristics,confirming the suitability for QTL mapping.A total of 37 QTLs were detected across both environments,including 18 specific to Hainan(Sanya),12 specific to Jiangxi(Nanchang),and 7 consistently identified in both locations.These QTLs were distributed on chromosomes 1—5,7,8,11,and 12,comprising 7 for thousand grains weight,5 for grain length,7 for grain width,11 for length-width ratio,and 7 for grain thickness.The analysis showed that the LOD values of these QTLs ranged from 2.79 to 43.10,with a contribution rate of 1.36% to 46.12%.By integrating differentially expressed genes from developing grains of both parents at three stages,28 candidate genes were prioritized from the 37 QTL regions.Among these,LOC_Os11g10480 and LOC_Os11g10100 were identified as key candidates for further functional validation.

The screening of aromatic rice germplasm resources and the rapid identification and utilization of aromatic genes have practical significance for the genetic breeding of aromatic rice.In order to clarify the aroma types of aromatic rice materials in Heilongjiang Province and improve the breeding efficiency of aromatic rice varieties,180 aromatic rice varieties approved and promoted in Heilongjiang Province were sequenced.Compared with the reference genome Nipponbare,the sequencing results were divided into two types of mutations.The first type was the 8 bp deletion of exon 7 and three base substitutions(Badh2-E7 type),including 177 varieties.The second type was the 7 bp deletion of exon 2(Badh2-E2 type),which contained only three varieties.According to these two mutation types,two specific KASP molecular markers were designed to accurately detect the aroma types of E7 and E2 in rice.Through the identification of 180 aromatic rice varieties,the typing results were consistent with the sequencing results.Two hybrid populations were constructed by using E7 aromatic rice variety Wuyoudao 4 and E2 aromatic rice variety Songkejing 134 with non-aromatic japonica rice varieties Weinong 101 and Dongfu 114,respectively.The F₂ generation of the hybrid population was screened and identified for aroma genes,and the identification results were consistent with 100%,which verified the accuracy of KASP molecular markers.The 620 japonica rice parents created and collected by our laboratory were further identified by KASP markers,and 248 aromatic rice materials were screened.It was found that these parents were all Badh2-E7 type genes.At the same time,the existing 1 220 F₇ generation materials with E7 aromatic rice as parents were genotyped,including 293 aromatic rice materials,906 non-aromatic rice materials and 21 heterozygous rice materials.Five aromatic and non-aromatic rice materials were randomly selected for sequencing verification.The sequencing results verified that the KASP molecular marker typing was correct.This study provided new markers and materials for breeding new fragrant rice varieties in cold regions by using molecular marker assisted selection.

This study aimed to investigate the effects of acidic soil on the growth metabolism and photosynthesis of Hainan green sweet orange (Citrus sinensis L.)and to elucidate its antioxidant regulatory mechanisms under acid stress.A pot experiment was conducted to analyze the physiological metabolic changes,antioxidant responses,and expression patterns of key antioxidant enzyme regulatory genes in green sweet orange under acid stress.The results showed that the plant height growth,leaf area and fresh weight of green sweet orange plants decreased significantly under a strongly acidic soil environment,with the most serious effect of pH 3.5 treatment;the weakly acidic(pH 6.5)soil could promote the growth of plants,which manifested as positive growth in the amount of each growth index.Strong acid treatment significantly impaired photosynthesis and normal growth metabolism of green sweet orange leaves,manifested as negative growth in transpiration rate(Tr)and stomatal conductance(Gs)were significantly reduced.Superoxide dismutase(SOD)and phenylalanine ammonia-lyase(PAL)activities increased by 6.60-fold and 5.90-fold at 24 h post-treatment under pH 3.5.The malondialdehyde(MDA)content in leaves treated with pH 3.5 increased by 6.47-fold compared to the initial time point(0 h),significantly higher than that under pH 6.5.Principal component analysis(PCA)and redundancy analysis(RDA)revealed a significant negative correlation between enzyme activity and physiological-biochemical indices(R²=0.82).Gene expression analysis demonstrated that CsSOD and CsPAL reached peak levels at 24,48 h post-stress respectively and remained upregulated within 72 h,showing 2.33-fold and 2.64-fold increases compared to 0 h,respectively.In summary,strongly acidic soil inhibits the growth and development of green sweet orange by reducing photosynthetic pigment content and metabolic efficiency.SOD and PAL serve as key antioxidant enzymes in response to acid stress,with CsSOD and CsPAL genes dynamically regulating enzymatic activity to mitigate stress.