Drought and salt stresses,the major environmental abiotic stresses in agriculture worldwide,affect plant growth,crop productivity,and quality.Therefore,developing crops with higher drought and salt tolerance is highly...Drought and salt stresses,the major environmental abiotic stresses in agriculture worldwide,affect plant growth,crop productivity,and quality.Therefore,developing crops with higher drought and salt tolerance is highly desirable.This study reported the isolation,biological function,and molecular characterization of a novel maspardin gene,OsMas1,from rice.The OsMas1 protein was localized to the cytoplasm.The expression levels of OsMas1 were up-regulated under mannitol,PEG6000,NaCl,and abscisic acid(ABA) treatments in rice.The OsMas1 gene was introduced into the rice cultivar Zhonghua 11(wild type,WT).OsMas1-overexpression(OsMas1-OE) plants exhibited significantly enhanced salt and drought tolerance;in contrast,OsMas1-interference(OsMas1-RNAi) plants exhibited decreased tolerance to salt and drought stresses,compared with WT.OsMas1-OE plants exhibited enhanced hypersensitivity,while OsMas1-RNAi plants showed less sensitivity to exogenous ABA treatment at both germination and post-germination stages.ABA,proline and K+ contents and superoxide dismutase(SOD),catalase(CAT),peroxidase(POD),and photosynthesis activities were significantly increased.In contrast,malonaldehyde(MDA),hydrogen peroxide(H2O2),superoxide anion radical(O2-··),and Na+ contents were significantly decreased in OsMas1-OE plants compared with OsMas1-RNAi and WT plants.Overexpression of OsMas1 up-regulated the genes involved in ABA signaling,proline biosynthesis,reactive oxygen species(ROS)-scavenging system,photosynthesis,and ion transport under salt and drought stresses.Our results indicate that the OsMas1 gene improves salt and drought tolerance in rice,which may serve as a candidate gene for enhancing crop resistance to abiotic stresses.展开更多
The advance of microelectronics requires the micropower of microsupercapacitors(MSCs) to possess wide temperature-and damage-tolerance beyond high areal energy density.The properties of electrolyte are crucial for MSC...The advance of microelectronics requires the micropower of microsupercapacitors(MSCs) to possess wide temperature-and damage-tolerance beyond high areal energy density.The properties of electrolyte are crucial for MSCs to meet the above requirements.Here,an organohydrogel electrolyte,featured with high salt tolerance,ultralow freezing point,and strong self-healing ability,is experimentally realized via modulating its inner dynamic bonds.Spectroscopic and theoretical analysis reveal that dimethyl sulfoxide has the ability to reconstruct Li^(+)solvation structure,and interact with free water and polyvinyl alcohol chains via forming hydrogen bonds.The organohydrogel electrolyte is employed to build MSCs,which show a boosted energy density,promising wide temperature range-and damage-tolerant ability.These attractive features make the designed organohydrogel electrolyte have great potential to advance MSCs.展开更多
A low-cost eco-friendly aqueous foam,especially the robust foam with great tolerance to high salinity and high temperature,is in great demand in the oil industry,e.g.,oil and gas well or geothermal well drilling.Herei...A low-cost eco-friendly aqueous foam,especially the robust foam with great tolerance to high salinity and high temperature,is in great demand in the oil industry,e.g.,oil and gas well or geothermal well drilling.Herein,an ultra-stable aqueous foam was developed using the biodegradable cellulose microfiber(CMF)as a foam stabilizer.The foam stabilized by CMF shows excellent tolerance to the high concentration of NaCl(6.0 wt%)and CaCl_(2)(0.25 wt%)and the related drainage half-life times(T_(0.5))reach 1750 and 2340 s respectively.By contrast,the foams without CMF are completely drained(T_(0.5)=0 s)when NaCl concentration is greater than 6.0 wt%or CaCl_(2) concentration is greater than 0.20 wt%.Notably,T0.5 of the foams stabilized by CMF at these saline concentrations still can maintain above 1000 s even after aging at 120℃ for 16 h,exhibiting an outstanding foam-stabilizing performance at high temperature.Experimental results suggest that the salt and high-temperature tolerance of CMF in foam stabilization is attributed to the electrically uncharged surfaces,the formation of a gel-like structure and the excellent thermal stability.This work not only provides a promising candidate of aqueous foam stabilizer to deal with high temperature and high salinity but also presents a natural-based solution for an environmentally friendly drilling industry in the future.展开更多
Amide-and alkyl-modified nanosilicas(AANPs)were synthesized and introduced into Xanthan gum(XG)solution,aiming to improve the temperature/salt tolerance and oil recovery.The rheological behaviors of XG/AANP hybrid dis...Amide-and alkyl-modified nanosilicas(AANPs)were synthesized and introduced into Xanthan gum(XG)solution,aiming to improve the temperature/salt tolerance and oil recovery.The rheological behaviors of XG/AANP hybrid dispersions were systematically studied at different concentrations,temperatures and inorganic salts.At high temperature(75C)and high salinity(10,000 mg,L1 NaCl),AANPs increase the apparent viscosity and dynamic modulus of the XG solution,and XG/AANP hybrid dispersion exhibits elastic-dominant properties.The most effective concentrations of XG and AANP interacting with each other are 1750 mg·L^(-1) and 0.74 wt%,respectively.The temperature tolerance of XG solution is not satisfactory,and high temperature further weakens the salt tolerance of XG.However,the AANPs significantly enhance the viscoelasticity the XG solution through hydrogen bonds and hydrophobic effect.Under reservoir conditions,XG/AANP hybrid recovers approximately 18.5%more OOIP(original oil in place)than AANP and 11.3%more OOIP than XG.The enhanced oil recovery mechanism of the XG/AANP hybrid is mainly increasing the sweep coefficient,the contribution from the reduction of oil-water interfacial tension is less.展开更多
Maize(Zea mays L.)is a global cereal crop whose demand is projected to double by 2050.Along with worsening of farmland salinization,salt stress has become a major environmental threat to the sustainability of maize pr...Maize(Zea mays L.)is a global cereal crop whose demand is projected to double by 2050.Along with worsening of farmland salinization,salt stress has become a major environmental threat to the sustainability of maize production worldwide.Accordingly,there is an urgent need to decipher salt-tolerant mechanisms and facilitate the breeding of salt-tolerant maize.As salt tolerance is a complex trait regulated by multiple genes,and maize germplasm varies widely in salt tolerance,efforts have been devoted to the identification and application of quantitative-trait loci(QTL)for salt tolerance.QTL associated with ion regulation,osmotic tolerance,and other aspects of salt tolerance have been discovered using genomewide association studies(GWAS),linkage mapping,and omics-based approaches.This review highlights recent advances in the molecular-level understanding of salt stress response in maize,in particular in(a)the discovery of salt-tolerance QTL,(b)the mechanisms of salt tolerance,(c)the development of salttolerant maize cultivars,and(d)current challenges and future prospects.展开更多
The Ca^(2+)/CaM signal transduction pathway helps plants adapt to environmental stress. However, our knowledge on the functional proteins of C^(2+)/CaM pathway in peanut(Arachis hypogeae L.) remains limited. In the pr...The Ca^(2+)/CaM signal transduction pathway helps plants adapt to environmental stress. However, our knowledge on the functional proteins of C^(2+)/CaM pathway in peanut(Arachis hypogeae L.) remains limited. In the present study, a novel calmodulin 4(CaM4)-binding protein S-adenosyl-methionine synthetase 1(SAMS1) in peanut was identified using a yeast two-hybrid assay. Expression of AhSAMS1was induced by Ca^(2+), ABA, and salt stress. To elucidate the function of AhSAMS1, physiological and phenotypic analyses were performed with wild-type and transgenic materials. Overexpression of AhSAMS1increased spermidine and spermidine synthesis while decreased the contents of ethylene, thereby eliminating excessive reactive oxygen species(ROS) in transgenic lines under salt stress. AhSAMS1 reduced uptake of Na+and leakage of K+from mesophyll cells, and was less sensitive to salt stress during early seedling growth, in agreement with the induction of SOS and NHX genes Transcriptomics combined with epigenetic regulation uncovered relationships between differentially expressed genes and differentially methylated regions, which raised the salt tolerance and plants growth. Our findings support a model in which the role of AhSAMS1 in the ROS-dependent regulation of ion homeostasis was enhanced by Ca^(2+)/CaM while AhSAMS1-induced methylation was regulated by CaM, thus providing a new strategy for increasing the tolerance of plants to salt stress.展开更多
Salinity tolerance is an important physiological index for crop breeding.Roots are typically the first plant tissue to withstand salt stress.In this study,we found that the tomato(Solanum lycopersicum)trehalose-6-phos...Salinity tolerance is an important physiological index for crop breeding.Roots are typically the first plant tissue to withstand salt stress.In this study,we found that the tomato(Solanum lycopersicum)trehalose-6-phosphate phosphatase(SlTPP4)gene is induced by abscisic acid(ABA)and salt,and is mainly expressed in roots.Overexpression of SlTPP4 in tomato enhanced tolerance to salt stress,resulting in better growth performance.Under saline conditions,SlTPP4 overexpression plants demonstrated enhanced sucrose metabolism,as well as increased expression of genes related to salt tolerance.At the same time,expression of genes related to ABA biosynthesis and signal transduction was enhanced or altered,respectively.In-depth exploration demonstrated that SlTPP4 enhances Casparian band development in roots to restrict the intake of Na^(+).Our study thus clarifies the mechanism of SlTPP4-mediated salt tolerance,which will be of great importance for the breeding of salt-tolerant tomato crops.展开更多
Aquaporins play important regulatory roles in improving plant abiotic stress tolerance.To better understand whether the Os PIP1 genes collectively dominate the osmotic regulation in rice under salt stress,a cluster ed...Aquaporins play important regulatory roles in improving plant abiotic stress tolerance.To better understand whether the Os PIP1 genes collectively dominate the osmotic regulation in rice under salt stress,a cluster editing of the Os PIP1;1,Os PIP1;2 and Os PIP1;3 genes in rice was performed by CRISPR/Cas9 system.Sequencing showed that two mutants with Cas9-free,line 14 and line 18 were successfully edited.Briefly,line 14 deleted a single C base in both the Os PIP1;1 and Os PIP1;3 genes,and inserted a single T base in the Os PIP1;2 gene,respectively.While line 18 demonstrated an insertion of a single A base in the Os PIP1;1gene and a single T base in both the Os PIP1;2 and Os PIP1;3 genes,respectively.Multiplex editing of the Os PIP1 genes significantly inhibited photosynthetic rate and accumulation of compatible metabolites,but increased MDA contents and osmotic potentials in the mutants,thus delaying rice growth under salt stress.Functional loss of the Os PIP1 genes obviously suppressed the expressions of the Os PIP1,Os SOS1,Os CIPK24 and Os CBL4 genes,and increased the influxes of Na+and effluxes of K^(+)/H^(+)in the roots,thus accumulating more Na+in rice mutants under salt stress.This study suggests that the Os PIP1 genes are essential modulators collectively contributing to the enhancement of rice salt stress tolerance,and multiplex editing of the Os PIP1 genes provides insight into the osmotic regulation of the PIP genes.展开更多
Alfalfa(Medicago sativa L.),when exposed to abiotic stress such as salinity,suffers significant losses in yield and productivity.The present study evaluated the salinity tolerance of 12 alfalfa cultivars in vitro usin...Alfalfa(Medicago sativa L.),when exposed to abiotic stress such as salinity,suffers significant losses in yield and productivity.The present study evaluated the salinity tolerance of 12 alfalfa cultivars in vitro using five concentrations of sodium chloride(NaCl),ranging from 0 to 250 mmol L^(−1).The results obtained in the current study revealed that the Saudi cultivars,Kasimi and Hassawi,and the German cultivar(Berlin)had the highest salinity tolerance in terms of germination percentage(GP),corrected germination rate index(CGRI),days to reach 50%germination(GT_(50)),and ability to form cotyledonary and true leaves.Under mmol L^(−1) NaCl,the Saudi cultivar Kasimi cultivar showed GP,CGRI,and GT_(50) of 55.20%,123.15,and 3.77 days,respectively.Similarly,the German cultivar(Berlin)showed GP,CGRI,and GT_(50) of 50.06%,86.61,and 5.17 days,respectively.These findings might reveal a pivotal aspect in salt tolerance in alfalfa.Our results will help to select salt-tolerant alfalfa cultivars that could thrive in arid and semi-arid areas with salinity problems.展开更多
Polyamines play an important regulatory role during plant growth and development and adversity stress,and polyamine oxidase(PAO)is involved in polyamine catabolism.In this study,an up-regulated polyamine oxidase gene ...Polyamines play an important regulatory role during plant growth and development and adversity stress,and polyamine oxidase(PAO)is involved in polyamine catabolism.In this study,an up-regulated polyamine oxidase gene GmPAO1 was obtained by transcriptome sequencing analysis and screening at soybean seedling stages.Also,its expression pattern and function were analyzed.The identification results of transgenic GmPAO1 soybean positive lines showed that the relative expression level of GmPAO1 in the overexpressed lines was increased under salt stress.With increasing stress concentration,the seed germination rate decreased.However,the seed germination rate of the overexpressed lines was significantly higher than that of the control lines,and the phenotypic character of the root systems was also better than that of the control lines.The measurement of superoxide dismutase(SOD)and peroxidase(POD)activities and malondialdehyde and hydrogen peroxide contents revealed that the overexpressed soybean lines significantly increased the SOD and POD activities,significantly reducing the malondialdehyde content.Although the hydrogen peroxide content in the transformed plants gradually increased,the hydrogen peroxide content in the overexpression lines was still lower than that in the gene editing lines.Based on this,it was preliminarily judged that GmPAO1 can improve soybean salt tolerance.展开更多
Salinity is a global challenge to agricultural production. Understanding Na^+ sensing and transport in plants under salt stress will be of benefit for breeding robustly salt-tolerant crop species. In this review, firs...Salinity is a global challenge to agricultural production. Understanding Na^+ sensing and transport in plants under salt stress will be of benefit for breeding robustly salt-tolerant crop species. In this review, first, possible salt stress sensor candidates and the root meristem zone as a tissue harboring salt stress-sensing components are proposed. Then,the importance of Na^+ exclusion and vacuolar Na^+ sequestration in plant overall salt tolerance is highlighted. Other Na^+ regulation processes, including xylem Na^+ loading and unloading, phloem Na^+ recirculation, and Na^+ secretion, are discussed and summarized.Along with a summary of Na^+ transporters and channels, the molecular regulation of Na^+ transporters and channels in response to salt stress is discussed. Finally, some largely neglected issues in plant salt stress tolerance, including Na^+ concentration in cytosol and the role of Na^+ as a nutrient, are reviewed and discussed.展开更多
A population of recombinant inbred lines (RILs, F2:9), derived from a cross between IR26 (Oryza sativa subsp. indica) and Jiucaiqing (Oryza sativa subsp, japonica), was used to identify seed germination ability...A population of recombinant inbred lines (RILs, F2:9), derived from a cross between IR26 (Oryza sativa subsp. indica) and Jiucaiqing (Oryza sativa subsp, japonica), was used to identify seed germination ability of rice under 100 mmol/L NaCl for 10 days. Six germination traits including imbibition rate, germination rate, germination index, root length, shoot length and vigor index were investigated. A mixed major gene and polygene inheritance model was applied to conduct genetic analysis for germination ability. Significant differences were detected in all the germination traits under salt stress among RILs in rice, and the early germination stage (0-5 days) might be the salt sensitive stage. The frequency distributions of the germination traits under salt stress in the RIL population showed continuous segregation, suggesting that they were quantitative traits controlled by several genes. The germination traits under salt stress were regulated by two or three major genes plus polygene, and mainly dominated by major genes with high heritability values, accounting for 12.5%-99.0% of the total phenotypic variation. Each trait was controlled by the specific genetic model: imbibition rate was controlled by two major genes, germination index and vigor index by two major genes plus polygene, germination rate and shoot length by three major genes plus polygene, and root length by two major genes or two major genes plus polygene.展开更多
Crop yield loss due to soil salinization is an increasing threat to agriculture worldwide.Salt stress drastically affects the growth,development,and grain productivity of rice(Oryza sativa L.),and the improvement of r...Crop yield loss due to soil salinization is an increasing threat to agriculture worldwide.Salt stress drastically affects the growth,development,and grain productivity of rice(Oryza sativa L.),and the improvement of rice tolerance to salt stress is a desirable approach for meeting increasing food demand.The main contributors to salt toxicity at a global scale are Na^(+)and Cl^(-)ions,which affect up to 50%of irrigated soils.Plant responses to salt stress occur at the organismic,cellular,and molecular levels and are pleiotropic,involving(1)maintenance of ionic homeostasis,(2)osmotic adjustment,(3)ROS scavenging,and(4)nutritional balance.In this review,we discuss recent research progress on these four aspects of plant physiological response,with particular attention to hormonal and gene expression regulation and salt tolerance signaling pathways in rice.The information summarized here will be useful for accelerating the breeding of salt-tolerant rice.展开更多
The stress-associated protein (SAP) multigene family is conserved in both animals and plants. Its function in some an- imals and plants are known, but it is yet to be deciphered in wheat (Triticum aestivum L.). We...The stress-associated protein (SAP) multigene family is conserved in both animals and plants. Its function in some an- imals and plants are known, but it is yet to be deciphered in wheat (Triticum aestivum L.). We identified the wheat gene TaSAP17-D, a member of the SAP gene family with an AN1/AN1 conserved domain. Subcellular localization indicated that TaSAP17-D localized to the nucleus, cytoplasm, and cell membrane. Expression pattern analyses revealed that TaSAP17-D was highly expressed in seedlings and was involved in NaCI response, polyethylene glycol (PEG), cold, and exogenous abscisic acid (ABA). Constitutive expression of TaSAP17-D in transgenic Arabidopsis resulted in enhanced tolerance to salt stress, confirmed by improved multiple physiological indices and significantly upregulated marker genes related to salt stress response. Our results suggest that TaSAP17-D is a candidate gene that can be used to protect crop plants from salt stress.展开更多
Salinity impairs plant growth, limiting agricultural development. It is desirable to identify genes responding to salt stress and their mechanism of action. We identified a function of the Zea mays WRKY transcription ...Salinity impairs plant growth, limiting agricultural development. It is desirable to identify genes responding to salt stress and their mechanism of action. We identified a function of the Zea mays WRKY transcription factor, Zm WRKY104, in salt stress response. Zm WRKY104 was localized in the nucleus and showed transcriptional activation activity. Phenotypic and physiological analysis showed that overexpression of Zm WRKY104 in maize increased the tolerance of maize to salt stress and alleviated salt-induced increases in O;accumulation, malondialdehyde(MDA) content, and percent of electrolyte leakage. Further investigation showed that Zm WRKY104 increased SOD activity by regulating Zm SOD4 expression. Yeast onehybrid, electrophoretic mobility shift test, and chromatin immunoprecipitation–quantitative PCR assay showed that Zm WRKY104 bound directly to the promoter of Zm SOD4 by recognizing the W-box motif in vivo and in vitro. Phenotypic, physiological, and biochemical analysis showed that Zm SOD4 increased salt tolerance by alleviating salt-induced increases in O;accumulation, MDA content, and percent of electrolyte leakage under salt stress. Taken together, our results indicate that Zm WRKY104 positively regulates Zm SOD4 expression to modulate salt-induced O;accumulation, MDA content, and percent of electrolyte leakage, thus affecting salt stress response in maize.展开更多
Iron-sulfur cluster biosynthesis involving the nitrogen fixation(Nif) proteins has been proposed as a general mechanism acting in various organisms.NifU-like protein may play an important role in protecting plants a...Iron-sulfur cluster biosynthesis involving the nitrogen fixation(Nif) proteins has been proposed as a general mechanism acting in various organisms.NifU-like protein may play an important role in protecting plants against abiotic and biotic stresses.Based on the EST sequence selected from salt-stressed suppression subtractive hybridization(SSH) cDNA library constructed with a salt-tolerant mutant LM79,a NFU gene,termed IbNFU1,was cloned from sweetpotato(Ipomoea batatas(L.) Lam.) via rapid amplification of cDNA ends(RACE).The cDNA sequence of 1 117 bp contained an 846 bp open reading frame encoding a 281 amino acids polypeptide with a molecular weight of 30.5 kDa and an isoelectric point(pI) of 5.12.IbNFU1 gene contained a conserved Cys-X-X-Cys motif in C-terminal of the iron-sulfur cluster domain.The deduced amino acid sequence had 66.08 to 71.99% sequence identity to NFU genes reported in Arabidopsis thaliana,Eucalyptus grandis and Vitis vinifera.Real-time quantitative PCR analysis revealed that the expression level of IbNFU1 gene was significantly higher in the roots of the mutant LM79 compared to the wild-type Lizixiang.Transgenic tobacco(cv.Wisconsin 38) plants expressing IbNFU1 gene exhibited significantly higher salt tolerance compared to the untransformed control plants.It is proposed that IbNFU1 gene has an important function for salt tolerance of plants.展开更多
The NAC (NAM, ATAF1/2 and CUC2) transcription factor family plays a key role in plant development and responses to abiotic stress. GmNAC15 (Glyma 15g40510.1), a member of the NAC transcription factor family in soy...The NAC (NAM, ATAF1/2 and CUC2) transcription factor family plays a key role in plant development and responses to abiotic stress. GmNAC15 (Glyma 15g40510.1), a member of the NAC transcription factor family in soybean, was functionally characterized, especially with regard to its role in salt tolerance. In the present study, qRT-PCR (quantitative reverse transcription PCR) analysis indicated that GmNAC15 was induced by salt, drought, low temperature stress, and ABA treatment in roots and leaves. GmNAC15 overexpression in soybean (Glycine max) hairy roots enhanced salt tolerance. Transgenic hairy roots improved the survival of wild leaves; however, overexpression of GmNAC15 in hairy root couldn't influnce the expression level of GmNAC15 in leaf. GmNAC15 regulates the expression levels of genes responsive to salt stress. Altogether, these results provide experimental evidence of the positive effect of GmNAC15 on salt tolerance in soybean and the potential application of genetic manipulation to enhance the salt tolerance of important crops.展开更多
A cDNA clone encoding a vacuolar H+-pyrophosphatase (V-H+-PPase) was isolated from Hordeum brevisubulatum (Trin.) Link by using RACE method. Sequence analysis revealed that HbVP1 contained 2 319 nucleotides of open re...A cDNA clone encoding a vacuolar H+-pyrophosphatase (V-H+-PPase) was isolated from Hordeum brevisubulatum (Trin.) Link by using RACE method. Sequence analysis revealed that HbVP1 contained 2 319 nucleotides of open reading frame (ORF) and 420 nucleotides of 3′-untranslated region. Its encoding protein consisted of 773 amino acid residues, which includes 14 transmembrane helices. The predicated molecular mass is 80.4 kDa with pI of 4.90. The V-H+-PPases in higher plants shared low identity (40-55%) with those of protozoa, marine alga and archaebacteria. HbVP1 transcripts accumulated abundantly in roots, shoots and seeds, and it was also strongly induced by salt treatment.展开更多
The production of transgenic sweetpotato (cv.Xushu 18) plants exhibiting enhanced salt tolerance using salt overly sensitive (SOS) genes was achieved through Agrobacterium tumefaciens-mediated transformation.A.tum...The production of transgenic sweetpotato (cv.Xushu 18) plants exhibiting enhanced salt tolerance using salt overly sensitive (SOS) genes was achieved through Agrobacterium tumefaciens-mediated transformation.A.tumefaciens strain EHA105 harbors a binary vector pCAMBIA3301 with SOS genes (SOS1,SOS2 and SOS3) and bar gene.Selection culture was conducted using 0.3 mg L^-1 phosphinothricin (PPT).A total of 40 plants were produced from the inoculated 170 cell aggregates via somatic embryogenesis.PCR analysis showed that 37 of the 40 regenerated plants were transgenic plants.The in vitro assay demonstrated that superoxide dismutase (SOD) and proline were significantly more accumulated and malonaldehyde (MDA) was significantly less accumulated in 21 transgenic plants than in control plants when they were exposed to 86 mmol L^-1 NaCl.Salt tolerance of these 21 plants was further evaluated with Hoagland solution containing 0,51,86,and 120 mmol L^-1 NaCl in the greenhouse.The results indicated that 6 of them had significantly better growth and rooting ability than the remaining 15 transgenic plants and control plants.Expression of SOS genes in the 6 salt-tolerant transgenic plants was demonstrated by RT-PCR analysis.This study provides an alternative approach for improving salt tolerance of sweetpotato.展开更多
An F2 population derived from the cross between Jiucaiqing (Japonica) and IR36 (indica) was used to analyze the inheritance of salt tolerance in rice by genetic model of major-genes plus polygenes, and to map the corr...An F2 population derived from the cross between Jiucaiqing (Japonica) and IR36 (indica) was used to analyze the inheritance of salt tolerance in rice by genetic model of major-genes plus polygenes, and to map the corresponding QTLs by SSR molecular markers. Rice plants of P1, P2, F1 and F2 at 5- to 6- leaf stage were treated under 140 mmol/LNaCI for 10 days. Three indices representing the ability of salt tolerance of rice seedlings were measured, including salt tolerance rating (STR), Na+/K+ ratio in roots and dry matter weight of shoots (DWS). STR, Na+/K+ and DWS were all controlled by two major genes with modification by polygenes. Heritability of these traits from major genes was 17.8, 53.3 and 52.3%, respectively. The linkage map constructed by 62 SSR molecular markers covered a total length of about 1 142 cM. There were three QTLs detected for STR located on chromosome 1, 5 and 9, two QTLs for DWS on chromosomes 8 and 9, and two QTLs for Na+/K+ on chromosomes 2 and 6, one on each chromosome respectively. Single QTL accounted for 6.7 to 19.3% of phenotypic variation. Identification method of salt tolerance in rice and breeding of rice varieties with salt tolerance based on molecular markers assisted selection had been discussed.展开更多
基金supported by the Natural Science Foundation of Jiangsu Province, China (BK20191483)the Natural Science Fund for Colleges and Universities in Jiangsu Province, China (20KJA180004)+2 种基金the Postgraduate Practice Innovation Program of Jiangsu Province, China (SJCX20_1339)the College Student Practice Innovation Program of Jiangsu Province, China (202111049104H, 202211049133H and 202211049138H)the Talent Introduction Research Project of Huaiyin Institute of Technology, China (Z301B16534)。
文摘Drought and salt stresses,the major environmental abiotic stresses in agriculture worldwide,affect plant growth,crop productivity,and quality.Therefore,developing crops with higher drought and salt tolerance is highly desirable.This study reported the isolation,biological function,and molecular characterization of a novel maspardin gene,OsMas1,from rice.The OsMas1 protein was localized to the cytoplasm.The expression levels of OsMas1 were up-regulated under mannitol,PEG6000,NaCl,and abscisic acid(ABA) treatments in rice.The OsMas1 gene was introduced into the rice cultivar Zhonghua 11(wild type,WT).OsMas1-overexpression(OsMas1-OE) plants exhibited significantly enhanced salt and drought tolerance;in contrast,OsMas1-interference(OsMas1-RNAi) plants exhibited decreased tolerance to salt and drought stresses,compared with WT.OsMas1-OE plants exhibited enhanced hypersensitivity,while OsMas1-RNAi plants showed less sensitivity to exogenous ABA treatment at both germination and post-germination stages.ABA,proline and K+ contents and superoxide dismutase(SOD),catalase(CAT),peroxidase(POD),and photosynthesis activities were significantly increased.In contrast,malonaldehyde(MDA),hydrogen peroxide(H2O2),superoxide anion radical(O2-··),and Na+ contents were significantly decreased in OsMas1-OE plants compared with OsMas1-RNAi and WT plants.Overexpression of OsMas1 up-regulated the genes involved in ABA signaling,proline biosynthesis,reactive oxygen species(ROS)-scavenging system,photosynthesis,and ion transport under salt and drought stresses.Our results indicate that the OsMas1 gene improves salt and drought tolerance in rice,which may serve as a candidate gene for enhancing crop resistance to abiotic stresses.
基金National Natural Science Foundation of China(52072297 and 51907149)Key R&D Plan of Shaanxi Province(2021GXLH-Z-068)+1 种基金China Postdoctoral Science Foundation(2019M653609)the Young Talent Support Plan of Xi’an Jiaotong University。
文摘The advance of microelectronics requires the micropower of microsupercapacitors(MSCs) to possess wide temperature-and damage-tolerance beyond high areal energy density.The properties of electrolyte are crucial for MSCs to meet the above requirements.Here,an organohydrogel electrolyte,featured with high salt tolerance,ultralow freezing point,and strong self-healing ability,is experimentally realized via modulating its inner dynamic bonds.Spectroscopic and theoretical analysis reveal that dimethyl sulfoxide has the ability to reconstruct Li^(+)solvation structure,and interact with free water and polyvinyl alcohol chains via forming hydrogen bonds.The organohydrogel electrolyte is employed to build MSCs,which show a boosted energy density,promising wide temperature range-and damage-tolerant ability.These attractive features make the designed organohydrogel electrolyte have great potential to advance MSCs.
基金This work was supported by the National Natural Science Foundation of China(Grant No.51991361 and Grant No.51991362)the foundation of China University of Petroleum(Beijing)(Grant No.2462021YXZZ002).
文摘A low-cost eco-friendly aqueous foam,especially the robust foam with great tolerance to high salinity and high temperature,is in great demand in the oil industry,e.g.,oil and gas well or geothermal well drilling.Herein,an ultra-stable aqueous foam was developed using the biodegradable cellulose microfiber(CMF)as a foam stabilizer.The foam stabilized by CMF shows excellent tolerance to the high concentration of NaCl(6.0 wt%)and CaCl_(2)(0.25 wt%)and the related drainage half-life times(T_(0.5))reach 1750 and 2340 s respectively.By contrast,the foams without CMF are completely drained(T_(0.5)=0 s)when NaCl concentration is greater than 6.0 wt%or CaCl_(2) concentration is greater than 0.20 wt%.Notably,T0.5 of the foams stabilized by CMF at these saline concentrations still can maintain above 1000 s even after aging at 120℃ for 16 h,exhibiting an outstanding foam-stabilizing performance at high temperature.Experimental results suggest that the salt and high-temperature tolerance of CMF in foam stabilization is attributed to the electrically uncharged surfaces,the formation of a gel-like structure and the excellent thermal stability.This work not only provides a promising candidate of aqueous foam stabilizer to deal with high temperature and high salinity but also presents a natural-based solution for an environmentally friendly drilling industry in the future.
基金We gratefully acknowledge financial supports from the Major Program of National Natural Science Foundation of China(Grant No.42090024)the National Natural Science Foundation of China(Grant No.52004322)the Natural Science Foundation of Shandong Province,China(Grant No.ZR2020QE108).
文摘Amide-and alkyl-modified nanosilicas(AANPs)were synthesized and introduced into Xanthan gum(XG)solution,aiming to improve the temperature/salt tolerance and oil recovery.The rheological behaviors of XG/AANP hybrid dispersions were systematically studied at different concentrations,temperatures and inorganic salts.At high temperature(75C)and high salinity(10,000 mg,L1 NaCl),AANPs increase the apparent viscosity and dynamic modulus of the XG solution,and XG/AANP hybrid dispersion exhibits elastic-dominant properties.The most effective concentrations of XG and AANP interacting with each other are 1750 mg·L^(-1) and 0.74 wt%,respectively.The temperature tolerance of XG solution is not satisfactory,and high temperature further weakens the salt tolerance of XG.However,the AANPs significantly enhance the viscoelasticity the XG solution through hydrogen bonds and hydrophobic effect.Under reservoir conditions,XG/AANP hybrid recovers approximately 18.5%more OOIP(original oil in place)than AANP and 11.3%more OOIP than XG.The enhanced oil recovery mechanism of the XG/AANP hybrid is mainly increasing the sweep coefficient,the contribution from the reduction of oil-water interfacial tension is less.
基金supported by the National Natural Science Foundation of China(32101555,32001447,U2106229)China Postdoctoral Science Foundation(2021T140060,2020M670537)。
文摘Maize(Zea mays L.)is a global cereal crop whose demand is projected to double by 2050.Along with worsening of farmland salinization,salt stress has become a major environmental threat to the sustainability of maize production worldwide.Accordingly,there is an urgent need to decipher salt-tolerant mechanisms and facilitate the breeding of salt-tolerant maize.As salt tolerance is a complex trait regulated by multiple genes,and maize germplasm varies widely in salt tolerance,efforts have been devoted to the identification and application of quantitative-trait loci(QTL)for salt tolerance.QTL associated with ion regulation,osmotic tolerance,and other aspects of salt tolerance have been discovered using genomewide association studies(GWAS),linkage mapping,and omics-based approaches.This review highlights recent advances in the molecular-level understanding of salt stress response in maize,in particular in(a)the discovery of salt-tolerance QTL,(b)the mechanisms of salt tolerance,(c)the development of salttolerant maize cultivars,and(d)current challenges and future prospects.
基金supported by the National Key Technology Research and Development Program of China (2018YFD1000900)the Natural Science Foundation of Shandong Province(ZR2020MC094)+1 种基金the Natural Science Foundation of Shandong Province (ZR2021QC163)Special Funds for Local Science and Technology Development Guided by the Central Committee(YDZX20203700001861)。
文摘The Ca^(2+)/CaM signal transduction pathway helps plants adapt to environmental stress. However, our knowledge on the functional proteins of C^(2+)/CaM pathway in peanut(Arachis hypogeae L.) remains limited. In the present study, a novel calmodulin 4(CaM4)-binding protein S-adenosyl-methionine synthetase 1(SAMS1) in peanut was identified using a yeast two-hybrid assay. Expression of AhSAMS1was induced by Ca^(2+), ABA, and salt stress. To elucidate the function of AhSAMS1, physiological and phenotypic analyses were performed with wild-type and transgenic materials. Overexpression of AhSAMS1increased spermidine and spermidine synthesis while decreased the contents of ethylene, thereby eliminating excessive reactive oxygen species(ROS) in transgenic lines under salt stress. AhSAMS1 reduced uptake of Na+and leakage of K+from mesophyll cells, and was less sensitive to salt stress during early seedling growth, in agreement with the induction of SOS and NHX genes Transcriptomics combined with epigenetic regulation uncovered relationships between differentially expressed genes and differentially methylated regions, which raised the salt tolerance and plants growth. Our findings support a model in which the role of AhSAMS1 in the ROS-dependent regulation of ion homeostasis was enhanced by Ca^(2+)/CaM while AhSAMS1-induced methylation was regulated by CaM, thus providing a new strategy for increasing the tolerance of plants to salt stress.
基金supported by the National Natural Science Foundation of China(32172597)the Chongqing Post Doctoral Special Support Project,China(2112012724652268)+1 种基金the Chongqing Exceptional Young Talents Project,China(CQYC202005097)the Chongqing Natural Science Foundation,China(cstc2018jcyjAX0730)。
文摘Salinity tolerance is an important physiological index for crop breeding.Roots are typically the first plant tissue to withstand salt stress.In this study,we found that the tomato(Solanum lycopersicum)trehalose-6-phosphate phosphatase(SlTPP4)gene is induced by abscisic acid(ABA)and salt,and is mainly expressed in roots.Overexpression of SlTPP4 in tomato enhanced tolerance to salt stress,resulting in better growth performance.Under saline conditions,SlTPP4 overexpression plants demonstrated enhanced sucrose metabolism,as well as increased expression of genes related to salt tolerance.At the same time,expression of genes related to ABA biosynthesis and signal transduction was enhanced or altered,respectively.In-depth exploration demonstrated that SlTPP4 enhances Casparian band development in roots to restrict the intake of Na^(+).Our study thus clarifies the mechanism of SlTPP4-mediated salt tolerance,which will be of great importance for the breeding of salt-tolerant tomato crops.
基金supported by the National Key Research and Development Program of China (2021YFF1000402-2)the Key Project of Transgenic Crops Cultivation (2016ZX08010005-9)。
文摘Aquaporins play important regulatory roles in improving plant abiotic stress tolerance.To better understand whether the Os PIP1 genes collectively dominate the osmotic regulation in rice under salt stress,a cluster editing of the Os PIP1;1,Os PIP1;2 and Os PIP1;3 genes in rice was performed by CRISPR/Cas9 system.Sequencing showed that two mutants with Cas9-free,line 14 and line 18 were successfully edited.Briefly,line 14 deleted a single C base in both the Os PIP1;1 and Os PIP1;3 genes,and inserted a single T base in the Os PIP1;2 gene,respectively.While line 18 demonstrated an insertion of a single A base in the Os PIP1;1gene and a single T base in both the Os PIP1;2 and Os PIP1;3 genes,respectively.Multiplex editing of the Os PIP1 genes significantly inhibited photosynthetic rate and accumulation of compatible metabolites,but increased MDA contents and osmotic potentials in the mutants,thus delaying rice growth under salt stress.Functional loss of the Os PIP1 genes obviously suppressed the expressions of the Os PIP1,Os SOS1,Os CIPK24 and Os CBL4 genes,and increased the influxes of Na+and effluxes of K^(+)/H^(+)in the roots,thus accumulating more Na+in rice mutants under salt stress.This study suggests that the Os PIP1 genes are essential modulators collectively contributing to the enhancement of rice salt stress tolerance,and multiplex editing of the Os PIP1 genes provides insight into the osmotic regulation of the PIP genes.
基金funded by the Researchers Supporting Project No.(RSP-2021/390),King Saud University,Riyadh,Saudi Arabia.
文摘Alfalfa(Medicago sativa L.),when exposed to abiotic stress such as salinity,suffers significant losses in yield and productivity.The present study evaluated the salinity tolerance of 12 alfalfa cultivars in vitro using five concentrations of sodium chloride(NaCl),ranging from 0 to 250 mmol L^(−1).The results obtained in the current study revealed that the Saudi cultivars,Kasimi and Hassawi,and the German cultivar(Berlin)had the highest salinity tolerance in terms of germination percentage(GP),corrected germination rate index(CGRI),days to reach 50%germination(GT_(50)),and ability to form cotyledonary and true leaves.Under mmol L^(−1) NaCl,the Saudi cultivar Kasimi cultivar showed GP,CGRI,and GT_(50) of 55.20%,123.15,and 3.77 days,respectively.Similarly,the German cultivar(Berlin)showed GP,CGRI,and GT_(50) of 50.06%,86.61,and 5.17 days,respectively.These findings might reveal a pivotal aspect in salt tolerance in alfalfa.Our results will help to select salt-tolerant alfalfa cultivars that could thrive in arid and semi-arid areas with salinity problems.
基金supported by Jilin Province Science and Technology Development Plan Project,Grant No.20190103120JHJilin Province Science and Technology Development Plan-Outstanding Young Talents Fund Project,Grant No.20190103120J+1 种基金The fourth batch of Jilin Province Youth Science and Technology Talent Support Project,Grant No.QT202020National Natural Science Foundation of China Projects,Grant No.31801381.
文摘Polyamines play an important regulatory role during plant growth and development and adversity stress,and polyamine oxidase(PAO)is involved in polyamine catabolism.In this study,an up-regulated polyamine oxidase gene GmPAO1 was obtained by transcriptome sequencing analysis and screening at soybean seedling stages.Also,its expression pattern and function were analyzed.The identification results of transgenic GmPAO1 soybean positive lines showed that the relative expression level of GmPAO1 in the overexpressed lines was increased under salt stress.With increasing stress concentration,the seed germination rate decreased.However,the seed germination rate of the overexpressed lines was significantly higher than that of the control lines,and the phenotypic character of the root systems was also better than that of the control lines.The measurement of superoxide dismutase(SOD)and peroxidase(POD)activities and malondialdehyde and hydrogen peroxide contents revealed that the overexpressed soybean lines significantly increased the SOD and POD activities,significantly reducing the malondialdehyde content.Although the hydrogen peroxide content in the transformed plants gradually increased,the hydrogen peroxide content in the overexpression lines was still lower than that in the gene editing lines.Based on this,it was preliminarily judged that GmPAO1 can improve soybean salt tolerance.
基金supported by a Ph.D. scholarship provided by University of Tasmania (185466S9A),Australiathe Open Fund of State Key Laboratory of Tea Plant Biology Utilization at Anhui Agricultural University (SKLTOF20170112)
文摘Salinity is a global challenge to agricultural production. Understanding Na^+ sensing and transport in plants under salt stress will be of benefit for breeding robustly salt-tolerant crop species. In this review, first, possible salt stress sensor candidates and the root meristem zone as a tissue harboring salt stress-sensing components are proposed. Then,the importance of Na^+ exclusion and vacuolar Na^+ sequestration in plant overall salt tolerance is highlighted. Other Na^+ regulation processes, including xylem Na^+ loading and unloading, phloem Na^+ recirculation, and Na^+ secretion, are discussed and summarized.Along with a summary of Na^+ transporters and channels, the molecular regulation of Na^+ transporters and channels in response to salt stress is discussed. Finally, some largely neglected issues in plant salt stress tolerance, including Na^+ concentration in cytosol and the role of Na^+ as a nutrient, are reviewed and discussed.
文摘A population of recombinant inbred lines (RILs, F2:9), derived from a cross between IR26 (Oryza sativa subsp. indica) and Jiucaiqing (Oryza sativa subsp, japonica), was used to identify seed germination ability of rice under 100 mmol/L NaCl for 10 days. Six germination traits including imbibition rate, germination rate, germination index, root length, shoot length and vigor index were investigated. A mixed major gene and polygene inheritance model was applied to conduct genetic analysis for germination ability. Significant differences were detected in all the germination traits under salt stress among RILs in rice, and the early germination stage (0-5 days) might be the salt sensitive stage. The frequency distributions of the germination traits under salt stress in the RIL population showed continuous segregation, suggesting that they were quantitative traits controlled by several genes. The germination traits under salt stress were regulated by two or three major genes plus polygene, and mainly dominated by major genes with high heritability values, accounting for 12.5%-99.0% of the total phenotypic variation. Each trait was controlled by the specific genetic model: imbibition rate was controlled by two major genes, germination index and vigor index by two major genes plus polygene, germination rate and shoot length by three major genes plus polygene, and root length by two major genes or two major genes plus polygene.
基金supported by the Research Initiation Fund of Hunan Agricultural University(20154/5407419002)the Open Research Fund of the State Key Laboratory of Hybrid Rice,Hunan Hybrid Rice Research Center(2020KF05)+1 种基金the Hunan Science and Technology Major Project(2018NK1010)the Hunan Science and Technology Talents Support Project(2019TJ-Q08)。
文摘Crop yield loss due to soil salinization is an increasing threat to agriculture worldwide.Salt stress drastically affects the growth,development,and grain productivity of rice(Oryza sativa L.),and the improvement of rice tolerance to salt stress is a desirable approach for meeting increasing food demand.The main contributors to salt toxicity at a global scale are Na^(+)and Cl^(-)ions,which affect up to 50%of irrigated soils.Plant responses to salt stress occur at the organismic,cellular,and molecular levels and are pleiotropic,involving(1)maintenance of ionic homeostasis,(2)osmotic adjustment,(3)ROS scavenging,and(4)nutritional balance.In this review,we discuss recent research progress on these four aspects of plant physiological response,with particular attention to hormonal and gene expression regulation and salt tolerance signaling pathways in rice.The information summarized here will be useful for accelerating the breeding of salt-tolerant rice.
基金supported by the National Key Research and Development Program of China (2016YFD0100605)the Agricultural Science and Technology Innovation Program, China (ASTIP)
文摘The stress-associated protein (SAP) multigene family is conserved in both animals and plants. Its function in some an- imals and plants are known, but it is yet to be deciphered in wheat (Triticum aestivum L.). We identified the wheat gene TaSAP17-D, a member of the SAP gene family with an AN1/AN1 conserved domain. Subcellular localization indicated that TaSAP17-D localized to the nucleus, cytoplasm, and cell membrane. Expression pattern analyses revealed that TaSAP17-D was highly expressed in seedlings and was involved in NaCI response, polyethylene glycol (PEG), cold, and exogenous abscisic acid (ABA). Constitutive expression of TaSAP17-D in transgenic Arabidopsis resulted in enhanced tolerance to salt stress, confirmed by improved multiple physiological indices and significantly upregulated marker genes related to salt stress response. Our results suggest that TaSAP17-D is a candidate gene that can be used to protect crop plants from salt stress.
基金supported by the National Natural Science Foundation of China(32001445 and 31871534)the Natural Science Foundation of Jiangsu Province(BK20200557)the China Postdoctoral Science Foundation(2019M651846)。
文摘Salinity impairs plant growth, limiting agricultural development. It is desirable to identify genes responding to salt stress and their mechanism of action. We identified a function of the Zea mays WRKY transcription factor, Zm WRKY104, in salt stress response. Zm WRKY104 was localized in the nucleus and showed transcriptional activation activity. Phenotypic and physiological analysis showed that overexpression of Zm WRKY104 in maize increased the tolerance of maize to salt stress and alleviated salt-induced increases in O;accumulation, malondialdehyde(MDA) content, and percent of electrolyte leakage. Further investigation showed that Zm WRKY104 increased SOD activity by regulating Zm SOD4 expression. Yeast onehybrid, electrophoretic mobility shift test, and chromatin immunoprecipitation–quantitative PCR assay showed that Zm WRKY104 bound directly to the promoter of Zm SOD4 by recognizing the W-box motif in vivo and in vitro. Phenotypic, physiological, and biochemical analysis showed that Zm SOD4 increased salt tolerance by alleviating salt-induced increases in O;accumulation, MDA content, and percent of electrolyte leakage under salt stress. Taken together, our results indicate that Zm WRKY104 positively regulates Zm SOD4 expression to modulate salt-induced O;accumulation, MDA content, and percent of electrolyte leakage, thus affecting salt stress response in maize.
基金supported by the China Agricultural Research System (Sweetpotato)the National High-Tech Research and Development Program of China(2009AA10Z102)+1 种基金the National Transgenic Plants Project of China (2009ZX08009-064B)the National Natural Science Foundation of China (31071468)
文摘Iron-sulfur cluster biosynthesis involving the nitrogen fixation(Nif) proteins has been proposed as a general mechanism acting in various organisms.NifU-like protein may play an important role in protecting plants against abiotic and biotic stresses.Based on the EST sequence selected from salt-stressed suppression subtractive hybridization(SSH) cDNA library constructed with a salt-tolerant mutant LM79,a NFU gene,termed IbNFU1,was cloned from sweetpotato(Ipomoea batatas(L.) Lam.) via rapid amplification of cDNA ends(RACE).The cDNA sequence of 1 117 bp contained an 846 bp open reading frame encoding a 281 amino acids polypeptide with a molecular weight of 30.5 kDa and an isoelectric point(pI) of 5.12.IbNFU1 gene contained a conserved Cys-X-X-Cys motif in C-terminal of the iron-sulfur cluster domain.The deduced amino acid sequence had 66.08 to 71.99% sequence identity to NFU genes reported in Arabidopsis thaliana,Eucalyptus grandis and Vitis vinifera.Real-time quantitative PCR analysis revealed that the expression level of IbNFU1 gene was significantly higher in the roots of the mutant LM79 compared to the wild-type Lizixiang.Transgenic tobacco(cv.Wisconsin 38) plants expressing IbNFU1 gene exhibited significantly higher salt tolerance compared to the untransformed control plants.It is proposed that IbNFU1 gene has an important function for salt tolerance of plants.
基金supported by the National Key Research and Development Program of China (2016YFD0101005)the Agricultural Science and Technology Program for Innovation Team on Identification and excavation of Elite Crop Germplasm, Chinese Academy of Agricultural Sciences
文摘The NAC (NAM, ATAF1/2 and CUC2) transcription factor family plays a key role in plant development and responses to abiotic stress. GmNAC15 (Glyma 15g40510.1), a member of the NAC transcription factor family in soybean, was functionally characterized, especially with regard to its role in salt tolerance. In the present study, qRT-PCR (quantitative reverse transcription PCR) analysis indicated that GmNAC15 was induced by salt, drought, low temperature stress, and ABA treatment in roots and leaves. GmNAC15 overexpression in soybean (Glycine max) hairy roots enhanced salt tolerance. Transgenic hairy roots improved the survival of wild leaves; however, overexpression of GmNAC15 in hairy root couldn't influnce the expression level of GmNAC15 in leaf. GmNAC15 regulates the expression levels of genes responsive to salt stress. Altogether, these results provide experimental evidence of the positive effect of GmNAC15 on salt tolerance in soybean and the potential application of genetic manipulation to enhance the salt tolerance of important crops.
基金This work was supported by the National Natural Science Foundation of China(30471229)
文摘A cDNA clone encoding a vacuolar H+-pyrophosphatase (V-H+-PPase) was isolated from Hordeum brevisubulatum (Trin.) Link by using RACE method. Sequence analysis revealed that HbVP1 contained 2 319 nucleotides of open reading frame (ORF) and 420 nucleotides of 3′-untranslated region. Its encoding protein consisted of 773 amino acid residues, which includes 14 transmembrane helices. The predicated molecular mass is 80.4 kDa with pI of 4.90. The V-H+-PPases in higher plants shared low identity (40-55%) with those of protozoa, marine alga and archaebacteria. HbVP1 transcripts accumulated abundantly in roots, shoots and seeds, and it was also strongly induced by salt treatment.
基金supported by China Agriculture Research System(Sweetpotato)the National High-Tech R&D Program of China(2009AA10Z102)the National Transgenic Plants Project of China(2009ZX08009-064B)
文摘The production of transgenic sweetpotato (cv.Xushu 18) plants exhibiting enhanced salt tolerance using salt overly sensitive (SOS) genes was achieved through Agrobacterium tumefaciens-mediated transformation.A.tumefaciens strain EHA105 harbors a binary vector pCAMBIA3301 with SOS genes (SOS1,SOS2 and SOS3) and bar gene.Selection culture was conducted using 0.3 mg L^-1 phosphinothricin (PPT).A total of 40 plants were produced from the inoculated 170 cell aggregates via somatic embryogenesis.PCR analysis showed that 37 of the 40 regenerated plants were transgenic plants.The in vitro assay demonstrated that superoxide dismutase (SOD) and proline were significantly more accumulated and malonaldehyde (MDA) was significantly less accumulated in 21 transgenic plants than in control plants when they were exposed to 86 mmol L^-1 NaCl.Salt tolerance of these 21 plants was further evaluated with Hoagland solution containing 0,51,86,and 120 mmol L^-1 NaCl in the greenhouse.The results indicated that 6 of them had significantly better growth and rooting ability than the remaining 15 transgenic plants and control plants.Expression of SOS genes in the 6 salt-tolerant transgenic plants was demonstrated by RT-PCR analysis.This study provides an alternative approach for improving salt tolerance of sweetpotato.
文摘An F2 population derived from the cross between Jiucaiqing (Japonica) and IR36 (indica) was used to analyze the inheritance of salt tolerance in rice by genetic model of major-genes plus polygenes, and to map the corresponding QTLs by SSR molecular markers. Rice plants of P1, P2, F1 and F2 at 5- to 6- leaf stage were treated under 140 mmol/LNaCI for 10 days. Three indices representing the ability of salt tolerance of rice seedlings were measured, including salt tolerance rating (STR), Na+/K+ ratio in roots and dry matter weight of shoots (DWS). STR, Na+/K+ and DWS were all controlled by two major genes with modification by polygenes. Heritability of these traits from major genes was 17.8, 53.3 and 52.3%, respectively. The linkage map constructed by 62 SSR molecular markers covered a total length of about 1 142 cM. There were three QTLs detected for STR located on chromosome 1, 5 and 9, two QTLs for DWS on chromosomes 8 and 9, and two QTLs for Na+/K+ on chromosomes 2 and 6, one on each chromosome respectively. Single QTL accounted for 6.7 to 19.3% of phenotypic variation. Identification method of salt tolerance in rice and breeding of rice varieties with salt tolerance based on molecular markers assisted selection had been discussed.