Alginate oligosaccharides(AOS)enhance drought resistance in wheat(Triticum aestivum L.),but the definite mechanisms remain largely unknown.The physiological and transcriptome responses of wheat seedlings treated with ...Alginate oligosaccharides(AOS)enhance drought resistance in wheat(Triticum aestivum L.),but the definite mechanisms remain largely unknown.The physiological and transcriptome responses of wheat seedlings treated with AOS were analyzed under drought stress simulated with polyethylene glycol-6000.The results showed that AOS promoted the growth of wheat seedlings and reduced oxidative damage by improving peroxidase and superoxide dismutase activities under drought stress.A total of 10,064 and 15,208 differentially expressed unigenes(DEGs)obtained from the AOS treatment and control samples at 24 and 72 h after dehydration,respectively,were mainly enriched in the biosynthesis of secondary metabolites(phenylpropanoid biosynthesis,flavonoid biosynthesis),carbohydrate metabolism(starch and sucrose metabolism,carbon fixation in photosynthetic organisms),lipid metabolism(fatty acid elongation,biosynthesis of unsaturated fatty acids,alpha-linolenic acid metabolism,cutin,suberine and wax biosynthesis),and signaling transduction pathways.The up-regulated genes were related to,for example,chlorophyll a-b binding protein,amylosynthease,phosphotransferase,peroxidase,phenylalanine ammonia lyase,flavone synthase,glutathione synthetase.Signaling molecules(including MAPK,plant hormones,H_(2)O_(2) and calcium)and transcription factors(mainly including NAC,MYB,MYB-related,WRKY,bZIP family members)were involved in the AOS-induced wheat drought resistance.The results obtained in this study help underpin the mechanisms of wheat drought resistance improved by AOS,and provides a theoretical basis for the application of AOS as an environmentally sustainable biological method to improve drought resistance in agriculture.展开更多
A rice cyclase gene,OsCYL4b,identified as an alternative splice variant of the cyclase gene OsCYL4a,is involved in the regulation of drought stress and oxidative response.Compared with OsCYL4a,OsCYL4b lacks the second...A rice cyclase gene,OsCYL4b,identified as an alternative splice variant of the cyclase gene OsCYL4a,is involved in the regulation of drought stress and oxidative response.Compared with OsCYL4a,OsCYL4b lacks the second exon,which is located in the conserved motif 3,and may be a functionally important site.Our results suggested that OsCYL4b was responsive to multiple abiotic stresses,and was localized to both the cytoplasm and plasma membrane.The overexpression of OsCYL4b resulted in significantly enhanced drought and osmotic stress tolerance,reduced water loss,and increased abscisic acid(ABA)content compared with the wild type(WT).展开更多
Drought stress caused by insufficient irrigation or precipitation impairs agricultural production worldwide.In this study,a two-year field experiment was conducted to investigate the effect of coronatine(COR),a functi...Drought stress caused by insufficient irrigation or precipitation impairs agricultural production worldwide.In this study,a two-year field experiment was conducted to investigate the effect of coronatine(COR),a functional analog of jasmonic acid(JA),on maize drought resistance.The experiment included two water treatments(rainfed and irrigation),four COR concentrations(mock,0μmol L^(-1);A1,0.1μmol L^(-1);A2,1μmol L^(-1);A3,10μmol L^(-1))and two maize genotypes(Fumin 985(FM985),a drought-resistant cultivar and Xianyu 335(XY335),a drought-sensitive cultivar).Spraying 1μmol L^(-1)COR at seedling stage increased surface root density and size,including root dry matter by 12.6%,projected root area by 19.0%,average root density by 51.9%,and thus root bleeding sap by 28.2%under drought conditions.COR application also increased leaf area and SPAD values,a result attributed to improvement of the root system and increases in abscisic acid(ABA),JA,and salicylic acid(SA)contents.The improvement of leaves and roots laid the foundation for increasing plant height and dry matter accumulation.COR application reduced anthesis and silking interval,increasing kernel number per ear.COR treatment at 1μmol L^(-1)increased the yield of XY335 and FM985 by 7.9%and 11.0%,respectively.Correlation and path analysis showed that grain yields were correlated with root dry weight and projected root area,increasing maize drought resistance mainly via leaf area index and dry matter accumulation.Overall,COR increased maize drought resistance mainly by increasing root dry weight and root area,with 1μmol L-^(-1)COR as an optimal concentration.展开更多
Reliance on agriculture for food security is a constant in all modern societies.Global climate change and population growth have put immense pressure on sustainable agriculture,exacerbating the effects of environmenta...Reliance on agriculture for food security is a constant in all modern societies.Global climate change and population growth have put immense pressure on sustainable agriculture,exacerbating the effects of environmental stresses.Drought is one of the most pressing abiotic stresses that farmers face,presenting an annual threat to crop growth and yield.Crops have evolved extensive morphological,physiological,and molecular mechanisms to combat drought stress.Drought resistance is a polygenic trait,controlled by a complex genetic network and an array of genes working together to ensure plant survival.Many studies have aimed at dissecting the genetic mechanisms underlying drought resistance.Recent studies using linkage and association mapping have made progress in identifying genetic variations that affect drought-resistance traits.These loci may potentially be engineered by genetic transformation and genome editing aimed at developing new,stress-resistant crop cultivars.Here we summarize recent progress in elucidating the genetic basis of crop drought resistance.Molecular-breeding technologies such as marker-assisted selection,genome selection,gene transformation,and genome editing are currently employed to develop drought-resistant germplasm in a variety of crops.Recent advances in basic research and crop biotechnology covered in this review will facilitate delivery of drought-resistant crops with unprecedented efficiency.展开更多
Soluble sugars function not only as the energy and structural blocks supporting plants,but also as osmoregulators and signal molecules during plant adaptation to water deficit.Here,we investigated drought resistance i...Soluble sugars function not only as the energy and structural blocks supporting plants,but also as osmoregulators and signal molecules during plant adaptation to water deficit.Here,we investigated drought resistance in transgenic apple(Malus×domestica)overexpressing MdFRK2,a key gene regulating fructose content and sugar metabolism.There is no obvious phenotypic difference between MdFRK2-overexpressing transgenic plants and WT plants under the well-watered condition.However,the transgenic plants and the grafted plants using MdFRK2-overexpressing rootstock exhibited improved tolerance to drought stress.Overexpression of MdFRK2 significantly promoted the growth of root system under drought stress.RNA sequencing showed that under drought stress,genes involved in sugar metabolism,transcription regulation,signal transduction or hormone metabolism were differentially expressed in MdFRK2 transgenic plants.Consistent with the gene expression profile,the activities of enzyme(SDH,FRK and NI)involved in sugar metabolism in the roots of MdFRK2 transgenic plants were significantly higher than those of untransformed control plants after drought stress.Under drought stress,overexpression of MdFRK2 promoted the accumulation of IAA,and decreased the contents of ABA and CK in apple root system.In conclusion,these results suggest that MdFRK2 can promote the growth of apple roots under drought stress by regulating sugar metabolism and accumulation,hormone metabolism and signal transduction,and then resist drought stress.展开更多
Sixteen cotton cultivars widely planted in China were sowed under five different drought concentrations(0,2.5,5,7.5,and 10%)using PEG6000 to screen the indices of drought resistance identification and explore the drou...Sixteen cotton cultivars widely planted in China were sowed under five different drought concentrations(0,2.5,5,7.5,and 10%)using PEG6000 to screen the indices of drought resistance identification and explore the drought resistance of different cotton cultivars.Eighteen physiological indices including root,stem,and leaf water contents(RWC,SWC,and LWC),net photosynthetic rate(Pn),the maximum photochemical quantum yield(Fv/Fm),the actual photochemical quantum yield(ΦPSII),non-photochemical quenching coefficient(NPQ),leaf water potential(LWP),osmotic potential(Ψs),leaf relative conductivity(REC),leaf proline content(Pro),leaf and root soluble protein contents(LSPC and RSPC),leaf and root malondialdehyde(MDA)contents(LMDA and RMDA),root superoxide dismutase,peroxidase,and catalase activities(RSOD,RPOD,and RCAT)were measured.Results indicated the 18 physiological indices can be converted into five or six independent comprehensive indices by principal component analysis,and nine typical indices(Fv/Fm,SWC,LWP,Pro,LMDA,RSPC,RMDA,RSOD,and RCAT)screened out by a stepwise regression method could be utilized to evaluate the drought resistance.Moreover,the 16 cotton cultivars were divided into four types:drought sensitive,drought weak sensitive,moderate drought resistant,and drought resistant types.The resistance ability of two selected cotton cultivars(drought resistant cultivar,Dexiamian 1;drought sensitive cultivar,Yuzaomian 9110)with contrasting drought sensitivities were further verified by pot experiment.Results showed that the responses of final cotton biomass,yield,and yield composition to drought were significantly different between the two cultivars.In conclusion,drought resistant cultivar Dexiamian 1 and drought sensitive cultivar Yuzaomian 9110 were screened through hydroponics experiment,which can be used as ideal experimental materials to study the mechanism of different cotton cultivars with contrasting drought sensitivities in response to drought stress.展开更多
[Objective] To establish drought resistance evaluation index system of desert shrubs,and provide scientific support for selecting quality tree species.[Method] Taking 2-year-old seedlings of 12 desert shrubs in Ulan B...[Objective] To establish drought resistance evaluation index system of desert shrubs,and provide scientific support for selecting quality tree species.[Method] Taking 2-year-old seedlings of 12 desert shrubs in Ulan Buh Desert ecosystem as the test materials,7 water physiological indexes were tested,principal component analysis and cluster analysis were applied to explore drought resistance of the shrubs.[Results](a) Water potential of Ephedra distachya Linn.,Nitraia tangutorum Bobr.,Caragana korshinski Kom.was lower than that of the other 9 species;bound water content(V_a) and bound water/free water ratio(V_a/V_s) of Zygophyl um xanthoxylon Maxim.was 64.20% and 3.3,higher than the others';transpiration rate of Atraphaxis bracteata A.Los.,Nitraia tangutorum Bobr.and Tamarix elongata Ldb.was significantly lower than the others';constant weight time of Haloxylon ammodendron(C.A.Mey.) Bunge and Ephedra distachya Linn.was the longest(144 h);residual moisture content of Ammopiptanthus mongolicus Maxim.was the highest(44.80%).(b) Water potential,bound water/free water(V_a/V_s),residual moisture content,bound water,constant weight time,and transpiration rate had great impact on drought resistance of plant,and the accumulative variance contribution rate achieved 87.59%.[Conclusion] According to the drought resistance,the 12 species were classified into 3 categories,namely shrubs with strong drought resistance(Ephedra distachya Linn.),shrubs with moderate drought resistance(Haloxylon ammodendron(C.A.Mey.) Bunge,Nitraia tangutorum Bobr.,and Zygophyllum xanthoxylon Maxim.);shrubs with poor drought resistance(Hedysarunn scoparium Fisch,Hedysarum mongolicum Turcz.,Tamarix elongata Ldb.,Caragana korshinskii Kom.,Ammopiptanthus mongolicus Maxim.,Atraphaxis bracteata A.Los.,Cal igonum mongolicum Mattei.,and Caragana microphylla Lam.).展开更多
Improving turfgrass drought resistance and save-water features are very important to solve water deficiency in turfgrass production and management. This research did some surveys of systematic literature review about ...Improving turfgrass drought resistance and save-water features are very important to solve water deficiency in turfgrass production and management. This research did some surveys of systematic literature review about turfgrass drought tolerance morphological characteristics, physiological characteristics and water use efficiency, and provided the detailed information for enhancing turfgrass drought resistant and water use efficiency in the future.展开更多
As one of the important materials in landscaping for flower terrace and border, Petunia hybrida needs high environmental conditions and its growth is seriously influenced by the drought. Silicon is considered to be a ...As one of the important materials in landscaping for flower terrace and border, Petunia hybrida needs high environmental conditions and its growth is seriously influenced by the drought. Silicon is considered to be a necessary element for plant growth, and soluble silicon can improve plant resilience. To improve the drought resilience of Petunia hybrida, the silicon transporter protein OsLsi1 and OsLsi2 genes cloned from rice(Oryza sative) were transferred into Petunia hybrida by Agrobacterium-mediated method, and finally got 26 and 32 positive plants, respectively by PCR and RT-PCR detections. With a control of non-transgenic plants, the obtained transgenic plants were taken by drought treatment stress for 0, 4, 7, 10 and 14 days, then re-watered and measured physiological indexes as malondialdehyde(MDA) content, free proline(Pro) content, superoxide dismutase(SOD) activity and peroxidase(POD) activity to study the effect of Petunia's drought resistance. All the results proved that the silicon transporter protein OsLsi1 and OsLsi2 genes were normally transcripted and expressed in transgenic Petunia hybrida; OsLsi1 gene could improve the abilities of plants' drought resistance and recover after drought stress, while OsLsi2 gene could reduce the above abilities. The order of the drought resistance ability of the three strains from strong to weak was OsLsi1>CK>OsLsi2; and silicon indeed improved the ability of drought resistance as well. All these results provided a new way to improve the drought resistance of Petunia, and laid a foundation to improve the ability of garden plants' drought resistance and water saving.展开更多
Soybean(Glycine max(L.)Merr.)is an important cultivated crop,which requires much water during its growth,and drought seriously affects soybean yields.Studies have shown that the expression of small heat shock proteins...Soybean(Glycine max(L.)Merr.)is an important cultivated crop,which requires much water during its growth,and drought seriously affects soybean yields.Studies have shown that the expression of small heat shock proteins can enhance drought resistance,cold resistance and salt resistance of plants.In this experiment,soybean GmHsps_p23-like gene was successfully cloned by RT-PCR,the protein encoded by the GmHsps_p23-like gene was subjected to bioinformatics analysis,and the pCAMBIA3301-GmHsps_p23-like overexpression vector and pCBSG015-GmHsps_p23-like gene editing vector were constructed.Agrobacterium-mediated method was used to transform soybeans to obtain positive plants.RT-PCR detection,rehydration experiment and drought resistance physiological and biochemical index detection were performed on the T2 generation positive transgenic soybean plants identified by PCR and Southern hybridization.The results showed that the overexpression vector plant GmHsps_p23-like gene expression increased.After rehydration,the transgenic overexpression plants returned to normal growth,and the damage to the plants was low.After drought stress,the SOD and POD activities and the PRO content of the transgenic overexpression plants increased,while the MDA content decreased.The reverse was true for soybean plants with genetically modified editing vectors.The drought resistance of the overexpressed soybeans under drought stress was higher than that of the control group,and had a stronger drought resistance.It showed that the expression of soybean GmHsps_p23-like gene can improve the drought resistance of soybean.The cloning and functional verification of soybean GmHsps_p23-like gene had not been reported yet.This is the first time that PCR technology has been used to amplify the soybean GmHsps_p23-like gene and construct an expression vector for this gene.This research has laid the foundation for transgenic technology to improve plant drought resistance and cultivate new drought-resistant transgenic soybean varieties.展开更多
Maize is the main grain crop and important forage crop in China. The correlation between ASI and yield of maize inbred lines and whether ASI and the ASI extension time(Dct) of maize inbred lines could be used as a dir...Maize is the main grain crop and important forage crop in China. The correlation between ASI and yield of maize inbred lines and whether ASI and the ASI extension time(Dct) of maize inbred lines could be used as a direct indicator of drought resistance of maize inbred lines were explored. The results showed that the goodness of fit of ASI and Dct with DI were 0.478 and 0.829, respectively, and the ASI had an extremely significant negative correlation with yield per plant. ASI and Dct could be used as a parameter to evaluate drought resistance of maize inbred lines, but Dct was more effective than ASI in determining drought resistance index(DI) of maize inbred lines.展开更多
[Objectives]This study was conducted to improve the drought resistance of rice and cultivate new varieties of drought-tolerant rice to effectively alleviate the reduction in rice yield caused by drought.[Methods]Twent...[Objectives]This study was conducted to improve the drought resistance of rice and cultivate new varieties of drought-tolerant rice to effectively alleviate the reduction in rice yield caused by drought.[Methods]Twenty two indica and japonica rice varieties were tested to compare the yield differences under drought stress in the whole growth period and under drought stress in the flowering period.[Results]Drought stress in the whole growth period and flowering period significantly reduced rice yield,as well as the number of filled grains per plant,the number of filled grains per panicle and grain weight per plant.To evaluate the drought tolerance of rice varieties,relative yield could be used as the index under both drought stresses in the whole growth period and the flowering period.[Conclusions]This study provides a theoretical reference for drought-tolerant rice breeding and screening.展开更多
Rice is the main grain crop in China. With global warming, drought and water shortage have become one of the important factors limiting rice production. Improving the drought resistance of rice can effectively allevia...Rice is the main grain crop in China. With global warming, drought and water shortage have become one of the important factors limiting rice production. Improving the drought resistance of rice can effectively alleviate the loss of rice yield caused by drought. In this paper, the research progress on rice drought resistance and its evaluation methods, mapping of QTLs for drought resistance-related traits, and mining for drought resistance genes were reviewed, and molecular breeding for drought resistance in rice was prospected.展开更多
The water deficit in arid and semi-arid regions is the primary limiting factor for the development of urban greenery and forestation. In addition, planting the species that consume low levels of water is useful in ari...The water deficit in arid and semi-arid regions is the primary limiting factor for the development of urban greenery and forestation. In addition, planting the species that consume low levels of water is useful in arid and semi-arid regions that have poor water management measures. Leaf water potential(Ψ) is a physiological parameter that can be used to identify drought resistance in various species. Indeed, Ψ is one of the most important properties of a plant that can be measured using a pressure chamber. Drought avoiding or drought resistant species have a lower Ψ than plants that use normal or high levels of water. To determine drought resistance of species that are suitable for afforestation in arid urban regions, we evaluated twenty woody species in the Isfahan City, central Iran. The experimental design was random split-split plots with five replications. The species were planted outdoor in plastic pots and then subjected to treatments that consisted of two soil types and five drip irrigation regimes. To evaluate the resistance of each species to drought, we used the Ψ and the number of survived plants to obtain the drought resistance index(DRI). Then, cluster analysis, dendrogram, and similarity index were used to group the species using DRI. Result indicates that the evaluated species were classified into five groups:(1) high water consuming species(DRI>–60 MPa);(2) above normal water consuming species(–60 MPa≥DRI>–90 MPa);(3) normal water consuming species(–90 MPa≥DRI>–120 MPa);(4) semi-drought resistant species(–120 MPa≥DRI>–150 MPa);and(5) drought resistant species(DRI≤–150 MPa). According to the DRI, Salix babylonica L., Populus alba L., and P. nigra L. are high water consuming species, Platanus orientalis L. and Albizia julibrissin Benth are normal water consuming species, and Quercus infectoria Oliv. and Olea europaea L. can be considered as drought resistant species.展开更多
Rice is one of the most important crops, providing staple food for about half population of the world. Drought stress affects plant growth and development seriously. This article reviewed the research progress of the ...Rice is one of the most important crops, providing staple food for about half population of the world. Drought stress affects plant growth and development seriously. This article reviewed the research progress of the physiological and molecular biology mechanism including osmotic adjustment, scavenging oxidative radicals, endogenous hormones, drought-resistance genes and epigenetic modification, it may be afford interrelated reference for increasing rice drought resistance and breeding drought resistance rice varieties.展开更多
DNA-binding one zinc-finger(Dof)proteins constitute a family of transcription factors with a highly conserved Dof domain that contains a C2C2 zinc-finger motif.Although several studies have demonstrated that Dof prote...DNA-binding one zinc-finger(Dof)proteins constitute a family of transcription factors with a highly conserved Dof domain that contains a C2C2 zinc-finger motif.Although several studies have demonstrated that Dof proteins are involved in multiple plant processes,including development and stress resistance,the functions of these proteins in drought stress resistance are largely unknown.Here,we report the identification of the MdDof54 gene from apple and document its positive roles in apple drought resistance.After long-term drought stress,compared with nontransgenic plants,MdDof54 RNAi plants had significantly shorter heights and weaker root systems;the transgenic plants also had lower shoot and root hydraulic conductivity,as well as lower photosynthesis rates.By contrast,compared with nontransgenic plants,MdDof54-overexpressing plants had higher photosynthesis rates and shoot hydraulic conductivity under long-term drought stress.Moreover,compared with nontransgenic plants,MdDof54-overexpressing plants had higher survival percentages under short-term drought stress,whereas MdDof54 RNAi plants had lower survival percentages.MdDof54 RNAi plants showed significant downregulation of 99 genes and significant upregulation of 992 genes in response to drought,and 366 of these genes were responsive to drought.We used DAPseq and ChIP-seq analyses to demonstrate that MdDof54 recognizes cis-elements that contain an AAAG motif.Taken together,our results provide new information on the functions of MdDof54 in plant drought stress resistance as well as resources for apple breeding aimed at the improvement of drought resistance.展开更多
MdMYB88 and MdMYB124 have been demonstrated to be responsible for lignin accumulation in apple under drought stress.In this study,using a metabolomic approach,we identified differentially accumulated phenylpropanoid a...MdMYB88 and MdMYB124 have been demonstrated to be responsible for lignin accumulation in apple under drought stress.In this study,using a metabolomic approach,we identified differentially accumulated phenylpropanoid and flavonoid metabolites in MdMYB88/124 transgenic RNAi plants under control and long-term drought stress conditions in apple roots.We confirmed the regulation of phenylalanine by MdMYB88 and MdMYB124 via UPLC-MS in apple roots under both control and drought conditions.Using Electrophoretic Mobility Shift Assay(EMSA)and ChIPquantitative PCR(qPCR)analyses,we found that MdMYB88 positively regulates the MdCM2 gene,which is responsible for phenylalanine biosynthesis,through binding to its promoter region.Under long-term drought conditions,MdMYB88/124 RNAi plants consistently accumulated increased amounts of H2O2 and MDA,while MdMYB88 and MdMYB124 overexpression plants accumulated decreased amounts of H2O2 and MDA.We also examined the accumulation of metabolites in the phenylpropanoid biosynthesis pathway in the leaves of MdMYB88 and MdMYB124 transgenic apple plants after long-term drought stress.We found that metabolites responsible for plant defense,including phenylpropanoids and flavonoids,accumulated less in the RNAi plants but more in the overexpression plants under both control and drought conditions.We further demonstrated that MdMYB88/124 RNAi plants were more sensitive to Alternaria alternata f.sp.mali and Valsa mali,two pathogens that currently severely threaten apple production.In contrast,MdMYB88 and MdMYB124 overexpression plants were more tolerant to these pathogens.The cumulative results of this study provided evidence for secondary metabolite regulation by MdMYB88 and MdMYB124,further explained the molecular roles of MdMYB88 and MdMYB124 in drought resistance,and provided information concerning molecular aspects of their roles in disease resistance.展开更多
The function of serrate(SE)in miRNA biogenesis in Arabidopsis is well elucidated,whereas its role in plant drought resistance is largely unknown.In this study,we report that MdSE acts as a negative regulator of apple(...The function of serrate(SE)in miRNA biogenesis in Arabidopsis is well elucidated,whereas its role in plant drought resistance is largely unknown.In this study,we report that MdSE acts as a negative regulator of apple(Malus×domestica)drought resistance by regulating the expression levels of MdMYB88 and MdMYB124 and miRNAs,including mdm-miR156,mdm-miR166,mdm-miR172,mdm-miR319,and mdm-miR399.MdSE interacts with MdMYB88 and MdMYB124,two positive regulators of apple drought resistance.MdSE decreases the transcript and protein levels of MdMYB88 and MdMYB124,which directly regulate the expression of MdNCED3,a key enzyme in abscisic acid(ABA)biosynthesis.Furthermore,MdSE is enriched in the same region of the MdNECD3 promoter where MdMYB88/MdMYB124 binds.Consistently,MdSE RNAi transgenic plants are more sensitive to ABA-induced stomatal closure,whereas MdSE OE plants are less sensitive.In addition,under drought stress,MdSE is responsible for the biogenesis of mdm-miR399,a negative regulator of drought resistance,and negatively regulates miRNAs,including mdm-miR156,mdm-miR166,mdm-miR172,and mdm-miR319,which are positive regulators of drought resistance.Taken together,by revealing the negative role of MdSE,our results broaden our understanding of the apple drought response and provide a candidate gene for apple drought improvement through molecular breeding.展开更多
Th IPK2 is an inositol polyphosphate kinase gene cloned from Thellungiella halophila that participates in diverse cellular processes. Drought is a major limiting factor in wheat(Triticum aestivum L.) production. The p...Th IPK2 is an inositol polyphosphate kinase gene cloned from Thellungiella halophila that participates in diverse cellular processes. Drought is a major limiting factor in wheat(Triticum aestivum L.) production. The present study investigated whether the application of the Th IPK2 gene could increase the drought resistance of transgenic wheat. The codon-optimized Th IPK2 gene was transferred into common wheat through Agrobacterium-mediated transformation driven by either a constitutive maize ubiquitin promoter or a stress-inducible rd29 A promoter from Arabidopsis. Molecular characterization confirmed the presence of the foreign gene in the transformed plants. The transgenic expression of Th IPK2 in wheat led to significantly improve drought tolerance compared to that observed in control plants. Compared to the wild type(WT) plants, the transgenic plants showed higher seed germination rates, better developed root systems, a higher relative water content(RWC) and total soluble sugar content, and less cell membrane damage under drought stress conditions. The expression profiles showed different expression patterns with the use of different promoters. The codon-optimized Th IPK2 gene is a candidate gene to enhance wheat drought stress tolerance by genetic engineering.展开更多
There is evindence showing that stress susceptibility index(SSI)(1一Yd/Yp)/(1—(?)d/(?)p)used as a measure of drought resistance of crop on the field is an altered form of droughtresistance coefficient(DRC)(Yd/Yp).The...There is evindence showing that stress susceptibility index(SSI)(1一Yd/Yp)/(1—(?)d/(?)p)used as a measure of drought resistance of crop on the field is an altered form of droughtresistance coefficient(DRC)(Yd/Yp).The correlative coefficient SSI and DRC is r=-1.Therefore,the SSI doesn’t improve the defect of the DRC.After two years experiments per-formed by using thirty winter wheat varieties as trial materials,the concept of drought resistanceindex in crops was put forward.Its expressing equation is:the yield in drylan×drought resis-tance coefficient/average yield in dryland.It makes the drought resistance coefficient(physicalindex)correlate well with the yield in dryland(agronomy index)and is suitable for breeder.展开更多
基金This research was funded and supported by the National Natural Science Foundation of China(Grant Number 32001443)Zhengzhou Major Science and Technology Innovation Project of Henan Province of China(Grant Number 2020CXZX0085)Science and Technology Inovation Team of Henan Academy of Agricultural Sciences(Grant Number 2024TD2).
文摘Alginate oligosaccharides(AOS)enhance drought resistance in wheat(Triticum aestivum L.),but the definite mechanisms remain largely unknown.The physiological and transcriptome responses of wheat seedlings treated with AOS were analyzed under drought stress simulated with polyethylene glycol-6000.The results showed that AOS promoted the growth of wheat seedlings and reduced oxidative damage by improving peroxidase and superoxide dismutase activities under drought stress.A total of 10,064 and 15,208 differentially expressed unigenes(DEGs)obtained from the AOS treatment and control samples at 24 and 72 h after dehydration,respectively,were mainly enriched in the biosynthesis of secondary metabolites(phenylpropanoid biosynthesis,flavonoid biosynthesis),carbohydrate metabolism(starch and sucrose metabolism,carbon fixation in photosynthetic organisms),lipid metabolism(fatty acid elongation,biosynthesis of unsaturated fatty acids,alpha-linolenic acid metabolism,cutin,suberine and wax biosynthesis),and signaling transduction pathways.The up-regulated genes were related to,for example,chlorophyll a-b binding protein,amylosynthease,phosphotransferase,peroxidase,phenylalanine ammonia lyase,flavone synthase,glutathione synthetase.Signaling molecules(including MAPK,plant hormones,H_(2)O_(2) and calcium)and transcription factors(mainly including NAC,MYB,MYB-related,WRKY,bZIP family members)were involved in the AOS-induced wheat drought resistance.The results obtained in this study help underpin the mechanisms of wheat drought resistance improved by AOS,and provides a theoretical basis for the application of AOS as an environmentally sustainable biological method to improve drought resistance in agriculture.
基金supported by the Fundamental Research Funds for the Central Universities,South-Central Minzu University,China(Grant No.CZY23002)Hubei Province Natural Science Foundation of China(Grant No.2019CFB804).
文摘A rice cyclase gene,OsCYL4b,identified as an alternative splice variant of the cyclase gene OsCYL4a,is involved in the regulation of drought stress and oxidative response.Compared with OsCYL4a,OsCYL4b lacks the second exon,which is located in the conserved motif 3,and may be a functionally important site.Our results suggested that OsCYL4b was responsive to multiple abiotic stresses,and was localized to both the cytoplasm and plasma membrane.The overexpression of OsCYL4b resulted in significantly enhanced drought and osmotic stress tolerance,reduced water loss,and increased abscisic acid(ABA)content compared with the wild type(WT).
基金funded by National Key Research and Development Program of China(2017YFD0300405-2)。
文摘Drought stress caused by insufficient irrigation or precipitation impairs agricultural production worldwide.In this study,a two-year field experiment was conducted to investigate the effect of coronatine(COR),a functional analog of jasmonic acid(JA),on maize drought resistance.The experiment included two water treatments(rainfed and irrigation),four COR concentrations(mock,0μmol L^(-1);A1,0.1μmol L^(-1);A2,1μmol L^(-1);A3,10μmol L^(-1))and two maize genotypes(Fumin 985(FM985),a drought-resistant cultivar and Xianyu 335(XY335),a drought-sensitive cultivar).Spraying 1μmol L^(-1)COR at seedling stage increased surface root density and size,including root dry matter by 12.6%,projected root area by 19.0%,average root density by 51.9%,and thus root bleeding sap by 28.2%under drought conditions.COR application also increased leaf area and SPAD values,a result attributed to improvement of the root system and increases in abscisic acid(ABA),JA,and salicylic acid(SA)contents.The improvement of leaves and roots laid the foundation for increasing plant height and dry matter accumulation.COR application reduced anthesis and silking interval,increasing kernel number per ear.COR treatment at 1μmol L^(-1)increased the yield of XY335 and FM985 by 7.9%and 11.0%,respectively.Correlation and path analysis showed that grain yields were correlated with root dry weight and projected root area,increasing maize drought resistance mainly via leaf area index and dry matter accumulation.Overall,COR increased maize drought resistance mainly by increasing root dry weight and root area,with 1μmol L-^(-1)COR as an optimal concentration.
基金supported by the National Key Research and Development Program of China(2021YFD1200703)Beijing Outstanding Young Scientist Program(BJJWZYJH01201910019026)the National Natural Science Foundation of China(32171940)。
文摘Reliance on agriculture for food security is a constant in all modern societies.Global climate change and population growth have put immense pressure on sustainable agriculture,exacerbating the effects of environmental stresses.Drought is one of the most pressing abiotic stresses that farmers face,presenting an annual threat to crop growth and yield.Crops have evolved extensive morphological,physiological,and molecular mechanisms to combat drought stress.Drought resistance is a polygenic trait,controlled by a complex genetic network and an array of genes working together to ensure plant survival.Many studies have aimed at dissecting the genetic mechanisms underlying drought resistance.Recent studies using linkage and association mapping have made progress in identifying genetic variations that affect drought-resistance traits.These loci may potentially be engineered by genetic transformation and genome editing aimed at developing new,stress-resistant crop cultivars.Here we summarize recent progress in elucidating the genetic basis of crop drought resistance.Molecular-breeding technologies such as marker-assisted selection,genome selection,gene transformation,and genome editing are currently employed to develop drought-resistant germplasm in a variety of crops.Recent advances in basic research and crop biotechnology covered in this review will facilitate delivery of drought-resistant crops with unprecedented efficiency.
基金supported by the National Natural Science Foundation of China(Grant No.32001988)the National Natural Science Foundation of Shaanxi Province(Grant No.2020JC-21)+1 种基金the Open Project Program of State Key Laboratory of Crop Stress Biology for Arid Areas(Grant No.CSBAA2020002)the earmarked fund for the China Agriculture Research System(Grant No.CARS-27)。
文摘Soluble sugars function not only as the energy and structural blocks supporting plants,but also as osmoregulators and signal molecules during plant adaptation to water deficit.Here,we investigated drought resistance in transgenic apple(Malus×domestica)overexpressing MdFRK2,a key gene regulating fructose content and sugar metabolism.There is no obvious phenotypic difference between MdFRK2-overexpressing transgenic plants and WT plants under the well-watered condition.However,the transgenic plants and the grafted plants using MdFRK2-overexpressing rootstock exhibited improved tolerance to drought stress.Overexpression of MdFRK2 significantly promoted the growth of root system under drought stress.RNA sequencing showed that under drought stress,genes involved in sugar metabolism,transcription regulation,signal transduction or hormone metabolism were differentially expressed in MdFRK2 transgenic plants.Consistent with the gene expression profile,the activities of enzyme(SDH,FRK and NI)involved in sugar metabolism in the roots of MdFRK2 transgenic plants were significantly higher than those of untransformed control plants after drought stress.Under drought stress,overexpression of MdFRK2 promoted the accumulation of IAA,and decreased the contents of ABA and CK in apple root system.In conclusion,these results suggest that MdFRK2 can promote the growth of apple roots under drought stress by regulating sugar metabolism and accumulation,hormone metabolism and signal transduction,and then resist drought stress.
基金supported by the National Natural Science Foundation of China (31630051 and 31571606)the Jiangsu Collaborative Innovation Center for Modern Crop Production, China (JCIC-MCP)the earmarked fund for China Agriculture Research System (CARS-18-14)
文摘Sixteen cotton cultivars widely planted in China were sowed under five different drought concentrations(0,2.5,5,7.5,and 10%)using PEG6000 to screen the indices of drought resistance identification and explore the drought resistance of different cotton cultivars.Eighteen physiological indices including root,stem,and leaf water contents(RWC,SWC,and LWC),net photosynthetic rate(Pn),the maximum photochemical quantum yield(Fv/Fm),the actual photochemical quantum yield(ΦPSII),non-photochemical quenching coefficient(NPQ),leaf water potential(LWP),osmotic potential(Ψs),leaf relative conductivity(REC),leaf proline content(Pro),leaf and root soluble protein contents(LSPC and RSPC),leaf and root malondialdehyde(MDA)contents(LMDA and RMDA),root superoxide dismutase,peroxidase,and catalase activities(RSOD,RPOD,and RCAT)were measured.Results indicated the 18 physiological indices can be converted into five or six independent comprehensive indices by principal component analysis,and nine typical indices(Fv/Fm,SWC,LWP,Pro,LMDA,RSPC,RMDA,RSOD,and RCAT)screened out by a stepwise regression method could be utilized to evaluate the drought resistance.Moreover,the 16 cotton cultivars were divided into four types:drought sensitive,drought weak sensitive,moderate drought resistant,and drought resistant types.The resistance ability of two selected cotton cultivars(drought resistant cultivar,Dexiamian 1;drought sensitive cultivar,Yuzaomian 9110)with contrasting drought sensitivities were further verified by pot experiment.Results showed that the responses of final cotton biomass,yield,and yield composition to drought were significantly different between the two cultivars.In conclusion,drought resistant cultivar Dexiamian 1 and drought sensitive cultivar Yuzaomian 9110 were screened through hydroponics experiment,which can be used as ideal experimental materials to study the mechanism of different cotton cultivars with contrasting drought sensitivities in response to drought stress.
基金Sponsored by Scientific Research Program of National Forestry Public Welfare Trade(201504710)
文摘[Objective] To establish drought resistance evaluation index system of desert shrubs,and provide scientific support for selecting quality tree species.[Method] Taking 2-year-old seedlings of 12 desert shrubs in Ulan Buh Desert ecosystem as the test materials,7 water physiological indexes were tested,principal component analysis and cluster analysis were applied to explore drought resistance of the shrubs.[Results](a) Water potential of Ephedra distachya Linn.,Nitraia tangutorum Bobr.,Caragana korshinski Kom.was lower than that of the other 9 species;bound water content(V_a) and bound water/free water ratio(V_a/V_s) of Zygophyl um xanthoxylon Maxim.was 64.20% and 3.3,higher than the others';transpiration rate of Atraphaxis bracteata A.Los.,Nitraia tangutorum Bobr.and Tamarix elongata Ldb.was significantly lower than the others';constant weight time of Haloxylon ammodendron(C.A.Mey.) Bunge and Ephedra distachya Linn.was the longest(144 h);residual moisture content of Ammopiptanthus mongolicus Maxim.was the highest(44.80%).(b) Water potential,bound water/free water(V_a/V_s),residual moisture content,bound water,constant weight time,and transpiration rate had great impact on drought resistance of plant,and the accumulative variance contribution rate achieved 87.59%.[Conclusion] According to the drought resistance,the 12 species were classified into 3 categories,namely shrubs with strong drought resistance(Ephedra distachya Linn.),shrubs with moderate drought resistance(Haloxylon ammodendron(C.A.Mey.) Bunge,Nitraia tangutorum Bobr.,and Zygophyllum xanthoxylon Maxim.);shrubs with poor drought resistance(Hedysarunn scoparium Fisch,Hedysarum mongolicum Turcz.,Tamarix elongata Ldb.,Caragana korshinskii Kom.,Ammopiptanthus mongolicus Maxim.,Atraphaxis bracteata A.Los.,Cal igonum mongolicum Mattei.,and Caragana microphylla Lam.).
基金Supported by the National Nature Science Foundation (30871735 31272191)
文摘Improving turfgrass drought resistance and save-water features are very important to solve water deficiency in turfgrass production and management. This research did some surveys of systematic literature review about turfgrass drought tolerance morphological characteristics, physiological characteristics and water use efficiency, and provided the detailed information for enhancing turfgrass drought resistant and water use efficiency in the future.
基金Supported by the Fund of Science and Technology Research Project of Education Department in Heilongjiang Province(12531014)
文摘As one of the important materials in landscaping for flower terrace and border, Petunia hybrida needs high environmental conditions and its growth is seriously influenced by the drought. Silicon is considered to be a necessary element for plant growth, and soluble silicon can improve plant resilience. To improve the drought resilience of Petunia hybrida, the silicon transporter protein OsLsi1 and OsLsi2 genes cloned from rice(Oryza sative) were transferred into Petunia hybrida by Agrobacterium-mediated method, and finally got 26 and 32 positive plants, respectively by PCR and RT-PCR detections. With a control of non-transgenic plants, the obtained transgenic plants were taken by drought treatment stress for 0, 4, 7, 10 and 14 days, then re-watered and measured physiological indexes as malondialdehyde(MDA) content, free proline(Pro) content, superoxide dismutase(SOD) activity and peroxidase(POD) activity to study the effect of Petunia's drought resistance. All the results proved that the silicon transporter protein OsLsi1 and OsLsi2 genes were normally transcripted and expressed in transgenic Petunia hybrida; OsLsi1 gene could improve the abilities of plants' drought resistance and recover after drought stress, while OsLsi2 gene could reduce the above abilities. The order of the drought resistance ability of the three strains from strong to weak was OsLsi1>CK>OsLsi2; and silicon indeed improved the ability of drought resistance as well. All these results provided a new way to improve the drought resistance of Petunia, and laid a foundation to improve the ability of garden plants' drought resistance and water saving.
基金Jilin Province Education Department Science and Technology Research Project[JJKH20210350KJ]Jilin Province Science and Technology Guidance Program Project[20200402023NC]+1 种基金Jilin Provincial Natural Science Foundation Project[20200201027JC]Innovation and Entrepreneurship Training Program for College Students in Jilin Province[2021].
文摘Soybean(Glycine max(L.)Merr.)is an important cultivated crop,which requires much water during its growth,and drought seriously affects soybean yields.Studies have shown that the expression of small heat shock proteins can enhance drought resistance,cold resistance and salt resistance of plants.In this experiment,soybean GmHsps_p23-like gene was successfully cloned by RT-PCR,the protein encoded by the GmHsps_p23-like gene was subjected to bioinformatics analysis,and the pCAMBIA3301-GmHsps_p23-like overexpression vector and pCBSG015-GmHsps_p23-like gene editing vector were constructed.Agrobacterium-mediated method was used to transform soybeans to obtain positive plants.RT-PCR detection,rehydration experiment and drought resistance physiological and biochemical index detection were performed on the T2 generation positive transgenic soybean plants identified by PCR and Southern hybridization.The results showed that the overexpression vector plant GmHsps_p23-like gene expression increased.After rehydration,the transgenic overexpression plants returned to normal growth,and the damage to the plants was low.After drought stress,the SOD and POD activities and the PRO content of the transgenic overexpression plants increased,while the MDA content decreased.The reverse was true for soybean plants with genetically modified editing vectors.The drought resistance of the overexpressed soybeans under drought stress was higher than that of the control group,and had a stronger drought resistance.It showed that the expression of soybean GmHsps_p23-like gene can improve the drought resistance of soybean.The cloning and functional verification of soybean GmHsps_p23-like gene had not been reported yet.This is the first time that PCR technology has been used to amplify the soybean GmHsps_p23-like gene and construct an expression vector for this gene.This research has laid the foundation for transgenic technology to improve plant drought resistance and cultivate new drought-resistant transgenic soybean varieties.
基金Supported by National Key R&D Program of China(2016YFD0100103-18)。
文摘Maize is the main grain crop and important forage crop in China. The correlation between ASI and yield of maize inbred lines and whether ASI and the ASI extension time(Dct) of maize inbred lines could be used as a direct indicator of drought resistance of maize inbred lines were explored. The results showed that the goodness of fit of ASI and Dct with DI were 0.478 and 0.829, respectively, and the ASI had an extremely significant negative correlation with yield per plant. ASI and Dct could be used as a parameter to evaluate drought resistance of maize inbred lines, but Dct was more effective than ASI in determining drought resistance index(DI) of maize inbred lines.
基金Supported by Anhui Provincial Key Research and Development Program(202104f06020017,2022h11020011)Young Talent Fund of Anhui Academy of Agricultural SciencesAnhui Provincial Science and Technology Major Project(202003a06020005)。
文摘[Objectives]This study was conducted to improve the drought resistance of rice and cultivate new varieties of drought-tolerant rice to effectively alleviate the reduction in rice yield caused by drought.[Methods]Twenty two indica and japonica rice varieties were tested to compare the yield differences under drought stress in the whole growth period and under drought stress in the flowering period.[Results]Drought stress in the whole growth period and flowering period significantly reduced rice yield,as well as the number of filled grains per plant,the number of filled grains per panicle and grain weight per plant.To evaluate the drought tolerance of rice varieties,relative yield could be used as the index under both drought stresses in the whole growth period and the flowering period.[Conclusions]This study provides a theoretical reference for drought-tolerant rice breeding and screening.
基金Supported by Natural Science Foundation of Anhui Province (1908085MC93)Major Science and Technology Project of Anhui Province (2021d06050002)Anhui Province Joint Research on Improved Crop Varieties (Rice)。
文摘Rice is the main grain crop in China. With global warming, drought and water shortage have become one of the important factors limiting rice production. Improving the drought resistance of rice can effectively alleviate the loss of rice yield caused by drought. In this paper, the research progress on rice drought resistance and its evaluation methods, mapping of QTLs for drought resistance-related traits, and mining for drought resistance genes were reviewed, and molecular breeding for drought resistance in rice was prospected.
文摘The water deficit in arid and semi-arid regions is the primary limiting factor for the development of urban greenery and forestation. In addition, planting the species that consume low levels of water is useful in arid and semi-arid regions that have poor water management measures. Leaf water potential(Ψ) is a physiological parameter that can be used to identify drought resistance in various species. Indeed, Ψ is one of the most important properties of a plant that can be measured using a pressure chamber. Drought avoiding or drought resistant species have a lower Ψ than plants that use normal or high levels of water. To determine drought resistance of species that are suitable for afforestation in arid urban regions, we evaluated twenty woody species in the Isfahan City, central Iran. The experimental design was random split-split plots with five replications. The species were planted outdoor in plastic pots and then subjected to treatments that consisted of two soil types and five drip irrigation regimes. To evaluate the resistance of each species to drought, we used the Ψ and the number of survived plants to obtain the drought resistance index(DRI). Then, cluster analysis, dendrogram, and similarity index were used to group the species using DRI. Result indicates that the evaluated species were classified into five groups:(1) high water consuming species(DRI>–60 MPa);(2) above normal water consuming species(–60 MPa≥DRI>–90 MPa);(3) normal water consuming species(–90 MPa≥DRI>–120 MPa);(4) semi-drought resistant species(–120 MPa≥DRI>–150 MPa);and(5) drought resistant species(DRI≤–150 MPa). According to the DRI, Salix babylonica L., Populus alba L., and P. nigra L. are high water consuming species, Platanus orientalis L. and Albizia julibrissin Benth are normal water consuming species, and Quercus infectoria Oliv. and Olea europaea L. can be considered as drought resistant species.
文摘Rice is one of the most important crops, providing staple food for about half population of the world. Drought stress affects plant growth and development seriously. This article reviewed the research progress of the physiological and molecular biology mechanism including osmotic adjustment, scavenging oxidative radicals, endogenous hormones, drought-resistance genes and epigenetic modification, it may be afford interrelated reference for increasing rice drought resistance and breeding drought resistance rice varieties.
基金supported by the National Natural Science Foundation of China(31572106 and 31622049).
文摘DNA-binding one zinc-finger(Dof)proteins constitute a family of transcription factors with a highly conserved Dof domain that contains a C2C2 zinc-finger motif.Although several studies have demonstrated that Dof proteins are involved in multiple plant processes,including development and stress resistance,the functions of these proteins in drought stress resistance are largely unknown.Here,we report the identification of the MdDof54 gene from apple and document its positive roles in apple drought resistance.After long-term drought stress,compared with nontransgenic plants,MdDof54 RNAi plants had significantly shorter heights and weaker root systems;the transgenic plants also had lower shoot and root hydraulic conductivity,as well as lower photosynthesis rates.By contrast,compared with nontransgenic plants,MdDof54-overexpressing plants had higher photosynthesis rates and shoot hydraulic conductivity under long-term drought stress.Moreover,compared with nontransgenic plants,MdDof54-overexpressing plants had higher survival percentages under short-term drought stress,whereas MdDof54 RNAi plants had lower survival percentages.MdDof54 RNAi plants showed significant downregulation of 99 genes and significant upregulation of 992 genes in response to drought,and 366 of these genes were responsive to drought.We used DAPseq and ChIP-seq analyses to demonstrate that MdDof54 recognizes cis-elements that contain an AAAG motif.Taken together,our results provide new information on the functions of MdDof54 in plant drought stress resistance as well as resources for apple breeding aimed at the improvement of drought resistance.
基金supported by the National Key Research and Development Program of China(2018YFD1000100)the National Natural Science Foundation of China(31622049,31872080,and 31660565).
文摘MdMYB88 and MdMYB124 have been demonstrated to be responsible for lignin accumulation in apple under drought stress.In this study,using a metabolomic approach,we identified differentially accumulated phenylpropanoid and flavonoid metabolites in MdMYB88/124 transgenic RNAi plants under control and long-term drought stress conditions in apple roots.We confirmed the regulation of phenylalanine by MdMYB88 and MdMYB124 via UPLC-MS in apple roots under both control and drought conditions.Using Electrophoretic Mobility Shift Assay(EMSA)and ChIPquantitative PCR(qPCR)analyses,we found that MdMYB88 positively regulates the MdCM2 gene,which is responsible for phenylalanine biosynthesis,through binding to its promoter region.Under long-term drought conditions,MdMYB88/124 RNAi plants consistently accumulated increased amounts of H2O2 and MDA,while MdMYB88 and MdMYB124 overexpression plants accumulated decreased amounts of H2O2 and MDA.We also examined the accumulation of metabolites in the phenylpropanoid biosynthesis pathway in the leaves of MdMYB88 and MdMYB124 transgenic apple plants after long-term drought stress.We found that metabolites responsible for plant defense,including phenylpropanoids and flavonoids,accumulated less in the RNAi plants but more in the overexpression plants under both control and drought conditions.We further demonstrated that MdMYB88/124 RNAi plants were more sensitive to Alternaria alternata f.sp.mali and Valsa mali,two pathogens that currently severely threaten apple production.In contrast,MdMYB88 and MdMYB124 overexpression plants were more tolerant to these pathogens.The cumulative results of this study provided evidence for secondary metabolite regulation by MdMYB88 and MdMYB124,further explained the molecular roles of MdMYB88 and MdMYB124 in drought resistance,and provided information concerning molecular aspects of their roles in disease resistance.
基金supported by the National Key Research and Development Program of China(2019YFD1000100)the National Natural Science Foundation of China(31622049 and 31872080).
文摘The function of serrate(SE)in miRNA biogenesis in Arabidopsis is well elucidated,whereas its role in plant drought resistance is largely unknown.In this study,we report that MdSE acts as a negative regulator of apple(Malus×domestica)drought resistance by regulating the expression levels of MdMYB88 and MdMYB124 and miRNAs,including mdm-miR156,mdm-miR166,mdm-miR172,mdm-miR319,and mdm-miR399.MdSE interacts with MdMYB88 and MdMYB124,two positive regulators of apple drought resistance.MdSE decreases the transcript and protein levels of MdMYB88 and MdMYB124,which directly regulate the expression of MdNCED3,a key enzyme in abscisic acid(ABA)biosynthesis.Furthermore,MdSE is enriched in the same region of the MdNECD3 promoter where MdMYB88/MdMYB124 binds.Consistently,MdSE RNAi transgenic plants are more sensitive to ABA-induced stomatal closure,whereas MdSE OE plants are less sensitive.In addition,under drought stress,MdSE is responsible for the biogenesis of mdm-miR399,a negative regulator of drought resistance,and negatively regulates miRNAs,including mdm-miR156,mdm-miR166,mdm-miR172,and mdm-miR319,which are positive regulators of drought resistance.Taken together,by revealing the negative role of MdSE,our results broaden our understanding of the apple drought response and provide a candidate gene for apple drought improvement through molecular breeding.
基金supported by the Youth Foundation of Shandong Academy of Agricultural Science,China(2016YQN01)the National Science and Technology Major Project of the Ministry of Agriculture of China(2018ZX08009-10B)+3 种基金the National Natural Science Foundation of China(31601301,31501312,31401378)the Natural Science Foundation of Shandong Province,China(ZR2014CM006)the Youth Foundation of Crop Research Institute,Shandong Academy of Agricultural Sciences,China(3201-04)the Key Research and Development Plan of Shandong Province,China(2017GNC10113)。
文摘Th IPK2 is an inositol polyphosphate kinase gene cloned from Thellungiella halophila that participates in diverse cellular processes. Drought is a major limiting factor in wheat(Triticum aestivum L.) production. The present study investigated whether the application of the Th IPK2 gene could increase the drought resistance of transgenic wheat. The codon-optimized Th IPK2 gene was transferred into common wheat through Agrobacterium-mediated transformation driven by either a constitutive maize ubiquitin promoter or a stress-inducible rd29 A promoter from Arabidopsis. Molecular characterization confirmed the presence of the foreign gene in the transformed plants. The transgenic expression of Th IPK2 in wheat led to significantly improve drought tolerance compared to that observed in control plants. Compared to the wild type(WT) plants, the transgenic plants showed higher seed germination rates, better developed root systems, a higher relative water content(RWC) and total soluble sugar content, and less cell membrane damage under drought stress conditions. The expression profiles showed different expression patterns with the use of different promoters. The codon-optimized Th IPK2 gene is a candidate gene to enhance wheat drought stress tolerance by genetic engineering.
文摘There is evindence showing that stress susceptibility index(SSI)(1一Yd/Yp)/(1—(?)d/(?)p)used as a measure of drought resistance of crop on the field is an altered form of droughtresistance coefficient(DRC)(Yd/Yp).The correlative coefficient SSI and DRC is r=-1.Therefore,the SSI doesn’t improve the defect of the DRC.After two years experiments per-formed by using thirty winter wheat varieties as trial materials,the concept of drought resistanceindex in crops was put forward.Its expressing equation is:the yield in drylan×drought resis-tance coefficient/average yield in dryland.It makes the drought resistance coefficient(physicalindex)correlate well with the yield in dryland(agronomy index)and is suitable for breeder.
