Seed priming is an effective seed pretreatment technology that enhances germination and overall crop performance by optimizing seed hydration and metabolic processes before planting.Seed quality is a critical determin...Seed priming is an effective seed pretreatment technology that enhances germination and overall crop performance by optimizing seed hydration and metabolic processes before planting.Seed quality is a critical determinant of cotton(Gossypium hirsutum)crop performance,influencing germination,plant vigor,and yield.This study evaluates the effects of seed priming with potassium salts(1%and 2%KCl and K2SO4)on germination,morphological traits,and Cry1Ac gene expression in three Bt cotton cultivars(IUB-2013,NIAB-878B,FH-142)as Cry1Ac enhance the pest resistance in Bt cotton and reduce the plant’s dependence on chemical insecticides.Seeds were primed for six hours,air-dried,and sown in the field.Germination rates,plant height,number of bolls per plant,boll weight,seed cotton yield,and ginning outturn(GOT)were assessed at crop maturity.Cry1Ac gene expression was quantified to explore the influence of priming treatments on transgene activity.Results demonstrated that 1%K2SO4 priming significantly enhanced germination and yield-related traits,with Cry1Ac expression peaking in the IUB-2013 cultivar under 1%K2SO4 treatment.These findings suggest that potassium-based halopriming improves cotton seedling establishment and Bt gene expression.This study addresses the critical gaps in understanding the effects of seed halopriming on morphological traits,germination,and expression of the Cry1Ac gene in Bt cotton while providing a novel eco-friendly and cost-effective halopriming approach,offering the potential to improve cotton production.展开更多
Frequent drought events severely restrict global crop productivity,especially those occurring in the reproductive stages.Moderate drought priming during the earlier growth stages is a promising strategy for allowing p...Frequent drought events severely restrict global crop productivity,especially those occurring in the reproductive stages.Moderate drought priming during the earlier growth stages is a promising strategy for allowing plants to resist recurrent severe drought stress.However,the underlying mechanisms remain unclear.Here,we subjected wheat plants to drought priming during the vegetative growth stage and to severe drought stress at 10 days after anthesis.We then collected leaf samples at the ends of the drought priming and recovery periods,and at the end of drought stress for transcriptome sequencing in combination with phenotypic and physiological analyses.The drought-primed wheat plants maintained a lower plant temperature,with higher stomatal openness and photosynthesis,thereby resulting in much lower 1,000-grain weight and grain yield losses under the later drought stress than the non-primed plants.Interestingly,416 genes,including 27 transcription factors(e.g.,MYB,NAC,HSF),seemed to be closely related to the improved drought tolerance as indicated by the dynamic transcriptome analysis.Moreover,the candidate genes showed six temporal expression patterns and were significantly enriched in several stress response related pathways,such as plant hormone signal transduction,starch and sucrose metabolism,arginine and proline metabolism,inositol phosphate metabolism,and wax synthesis.These findings provide new insights into the physiological and molecular mechanisms of the long-term effects of early drought priming that can effectively improve drought tolerance in wheat,and may provide potential approaches for addressing the challenges of increasing abiotic stresses and securing food safety under global warming scenarios.展开更多
The impacts of drought stress on crop yield and quality are substantial. Drought priming during the early growth stage of plants has been shown to improve tolerance to drought stress during the reproductive stage, alt...The impacts of drought stress on crop yield and quality are substantial. Drought priming during the early growth stage of plants has been shown to improve tolerance to drought stress during the reproductive stage, although its effects on grain quality remain elusive. This study investigated the influence of drought priming on starch and protein levels in grains under drought stress during grain filling. Our results revealed that drought stress leads to a reduction in the contents of starch and its constituents, while simultaneously increasing glutenin macropolymers and protein fractions. Notably, drought primed plants under drought stress(PD) exhibited mitigated declines in the contents of starch and its components, leading to improvements in starch swelling power and pasting properties. In addition, PD resulted in a slight increase in the protein fractions, limiting the overall rise in total protein content compared to drought stress alone. The results of our study underscore the efficacy of drought priming as a strategy to counteract the negative effects of drought stress on grain quality, particularly by minimizing starch losses and restraining protein content elevation.展开更多
Nitrogen(N)priming is a microbially mediated biochemical process as affected by different incorporation practices.However,little information is known about the microbial mechanisms driving the response of N priming to...Nitrogen(N)priming is a microbially mediated biochemical process as affected by different incorporation practices.However,little information is known about the microbial mechanisms driving the response of N priming to co-operation of Chinese milk vetch(CMV,Astragalus sinicus L.)and different rates of chemical fertilizers in paddy soils in South China.Here,an anaerobic incubation experiment was conducted to study N priming effects(PE)and their relationships with soil microbial functional genes after CMV incorporation alone(M),co-incorporation of CMV with 100%(normal dosage)chemical fertilizers(MC100),and co-incorporation of CMV with 80% chemical fertilizers(MC80).Co-incorporation of CMV and chemical fertilizers enhanced the short-time scale(the first 20 d of incubation)positive PE of N,while no significant differences existed among the three treatments on day 60 or 90 of incubation(P>0.05).Compared with the M treatment,gross priming effect(GPE)in the MC100 and MC80 treatments significantly increased by 34.0% and 31.3%,respectively,and net priming effect(NPE)increased by 47.7% and 47.8%,respectively,during the first 20 d of incubation(P<0.05).This was likely attributed to soil nutrient availability and added substrate quality.The MC100 and MC80 treatments increased the gdhA gene abundance by 5.0% and 9.8%,increased the gdh2 gene abundance by 12.7% and 45.7%,and increased the nasB gene abundance by 9.5% and 41.4%,respectively,in comparison with the M treatment on day 20 of incubation.Correlation analyses indicated that soil microbial functional genes involved in N mineralization(gdhA and gdh2),assimilatory nitrate reduction(nasB),and nitrification(amoB)were significantly correlated with N priming under different incorporation practices during the incubation period(P<0.05).Thus,co-incorporation of CMV and chemical fertilizers can regulate soil microbial community functional gene structure,which may accelerate mineralization and assimilatory nitrate reduction and inhibit nitrification,thereby increasing the short-term positive PE of N in the present study.展开更多
Stem cell expansion in vitro and transplantation in the cytokine-rich proinflammatory milieu in the injured tissue generate immense oxidative stress that interferes with the cells’survival,stemness,and repairability....Stem cell expansion in vitro and transplantation in the cytokine-rich proinflammatory milieu in the injured tissue generate immense oxidative stress that interferes with the cells’survival,stemness,and repairability.Stem cell priming has gained popularity to overcome these issues.Given melatonin’s oxidative-scavenging properties,Gu et al have used periodontal ligament stem cells cultured under oxidative stress as an in vitro model to study the cytoprotective effects of melatonin.Our letter to the editor delves into melatonin-induced stem cell priming and the underlying molecular mechanism,focusing on the intriguing role of Yesassociated protein signaling in alleviating oxidative stress.We stress the importance of understanding the distinction between in vitro and in vivo oxidative stress conditions,a crucial aspect of stem cell research that invokes a sense of critical thinking in the readership.The study by Gu et al presents a novel approach to oxidative stress management,offering exciting possibilities for future research and applications.展开更多
Mesenchymal stromal/stem cells(MSCs)have garnered significant attention in the field of regenerative medicine due to their remarkable therapeutic potential.MSCs play a pivotal role in maintaining tissue homeostasis an...Mesenchymal stromal/stem cells(MSCs)have garnered significant attention in the field of regenerative medicine due to their remarkable therapeutic potential.MSCs play a pivotal role in maintaining tissue homeostasis and possess diverse functions in tissue repair and recovery in various organs.These cells are charac-terized by easy accessibility,few ethical concerns,and adaptability to in vitro cultures,making them a valuable resource for cell therapy in several clinical conditions.Over the years,it has been shown that the true therapeutic power of MSCs lies not in cell engraftment and replacement but in their ability to produce critical paracrine factors,including cytokines,growth factors,and exosomes(EXOs),which modulate the tissue microenvironment and facilitate repair and regeneration processes.Consequently,MSC-derived products,such as condi-tioned media and EXOs,are now being extensively evaluated for their potential medical applications,offering advantages over the long-term use of whole MSCs.However,the efficacy of MSC-based treatments varies in clinical trials due to both intrinsic differences resulting from the choice of diverse cell sources and non-standardized production methods.To address these concerns and to enhance MSC therapeutic potential,researchers have explored many priming strategies,including exposure to inflammatory molecules,hypoxic conditions,and three-dimensional culture techniques.These approaches have optimized MSC secretion of functional factors,empowering them with enhanced immunomodulatory,angiogenic,and regenerative properties tailored to specific medical conditions.In fact,various priming strategies show promise in the treatment of numerous diseases,from immune-related disorders to acute injuries and cancer.Currently,in order to exploit the full therapeutic potential of MSC therapy,the most important challenge is to optimize the modulation of MSCs to obtain adapted cell therapy for specific clinical disorders.In other words,to unlock the complete potential of MSCs in regenerative medicine,it is crucial to identify the most suitable tissue source and develop in vitro manipulation protocols specific to the type of disease being treated.展开更多
Seed priming is a pre-germinated technique that can enhance seed germination percentage,faster and synchro-nized germination,better seedling growth,and yield under stress conditions.To ascertain the most effective see...Seed priming is a pre-germinated technique that can enhance seed germination percentage,faster and synchro-nized germination,better seedling growth,and yield under stress conditions.To ascertain the most effective seed priming method that would ensure the potential yield of wheat in Bangladesh,two experiments were carried out from December 2021 to March 2022 at the Department of Agronomy,Bangladesh Agricultural University.Two wheat varieties namely BARI Gom-28 and BWMRI Gom-1 were subjected to a range of priming chemicals in both lab and pot tests.These compounds included the following:control(no priming),hydropriming(distilled water),10000 ppm KNO_(3),15000 ppm KNO_(3),40000 ppm Mannitol,60000 ppm Mannitol,10000 ppm NaCl,20000 ppm NaCl,100 ppm PEG,150 ppm PEG,500 ppm NaOCl,1000 ppm NaOCl,10000 ppm CaCl_(2),20000 ppm CaCl_(2),10000 ppm KCl and 20000 ppm KCl.A complete randomized design(CRD)with three repli-cations was used to set up the experiments.The results showed that BARI Gom-28 and BWMRI Gom-1 responded best to KCl priming in terms of rapid seed germination and strong seedling development.On the other hand,the best priming agents for plant growth and productivity turned out to be CaCl_(2) and KCL.The results of this study support the possibility of using seed priming as a technique to improve wheat plant development and output by raising seed emergence and survival rates.展开更多
Chilling is one of the major abiotic stresses for plants,especially for rice cultivation.Many essential metabolic processes for growth and development are temperature-dependent.In that case,reducing the negative effec...Chilling is one of the major abiotic stresses for plants,especially for rice cultivation.Many essential metabolic processes for growth and development are temperature-dependent.In that case,reducing the negative effects of cold stress using exogenous chemicals is a possible option.Therefore,the current study examined the effects of pre-sowing seed treatment with different chemicals,viz.hydrogen peroxide(H_(2)O_(2)),salicylic acid(SA),calcium chloride(CaCl_(2)),thiourea(TU),and citric acid(CA)on the germination of rice seeds(cv.BRRI dhan28)under chilling environments.Rice seeds were soaked in distilled water(control),10 mM CA,2 mM SA,10 mM CaCl_(2),10 mM H_(2)O_(2),and 10 mM TU solutions for 24 h.After that,seeds were exposed to chilling stress by incubating at 4±1℃ for 8 h,followed by at 25±2℃ for 16 h for 7 days.Exposure to chilling stress significantly reduced thefinal germination percent(13.6%),germination rate index(36.0%),coefficient of the velocity(25.0%),shoot fresh weight(44.4%),and root fresh weight(60.5%).Moreover,chilling induced oxidative damage and reduced the activity of antioxidant enzymes(catalase and ascorbate peroxidase).In contrast,treatments with H_(2)O_(2),SA,CaCl_(2),TU,and CA considerably enhanced germination indices and seedling growth compared to chilling stress condi-tions.The study showed that priming with H_(2)O_(2),SA,CaCl_(2),TU,and CA significantly boosted antioxidant enzyme activities and reduced MDA and H_(2)O_(2) contents in chilling-stressed rice plants,indicating less oxidative stress and improved tolerance.Principal component analysis showed that among these priming agents,H_(2)O_(2),SA,and CA are most effective in chilling stress mitigation.Therefore,using seed-treating chemicals to combat the effect of chilling stress can help rice seedlings grow better in the winter season.展开更多
Objective:Injury can lead to long-term changes that increase the sensitivity of afferent nerve endings to subsequent stimulation and pain can transition from acute to chronic.This phenomenon is known as hyperalgesic p...Objective:Injury can lead to long-term changes that increase the sensitivity of afferent nerve endings to subsequent stimulation and pain can transition from acute to chronic.This phenomenon is known as hyperalgesic priming(HP).This study aimed to understand the mechanisms underlying the effect of electroacupuncture(EA)on HP and optimize acupoint selection for EA to prevent pain transition.Methods:A rat HP model was established using sequential intraplantar injections of carrageenan(Cg)and prostaglandin E2(PGE2).The pain thresholds were measured using von Frey filaments.EA on bilateral Zusanli(ST36)and Kunlun(BL60)was used to prevent pain transition.The number of mast cells in the ipsilateral hindpaw skin was determined using toluidine blue or fluorescencelabeled avidin staining.The protein expression levels of protein kinase C epsilon(PKCε)in the lumbar dorsal root ganglions(DRGs)were detected by western blotting 24 h after PGE2 injection.Serial pharmacological experiments were conducted to evaluate the relationship between mast cells and pain transition.Finally,EA on the bilateral ST36 and Chongyang(ST42)or a novel combination(ST36 and ST42 on the ipsilateral side,and ST36 and BL60 on the contralateral side)was used to prevent pain transition.Results:Although EA applied to ST36 and BL60 alleviated acute pain induced by Cg injection,it failed to prevent the pain transition caused by PGE2 injection.Mast cell accumulation in the ipsilateral hind paw was observed 7 days after Cg injection.Furthermore,mast cell degranulation may be responsible for PKCεactivation in the DRG,a marker of pain transition.EA significantly decreased the number of mast cells in the skin of the ipsilateral hind paw when applied at ST36 and ST42,but not when applied at ST36 and BL60.Furthermore,EA employed to ST36 and ST42 significantly reversed long-term hyperalgesia induced by PGE2 injection,even when administered before injection.However,EA did not alleviate acute pain caused by Cg injection.By using a novel acupoint combination,EA simultaneously alleviated acute pain and prevented pain transition.Conclusions:Our study suggests that mast cells play a critical role in both HP and the transition from acute to chronic pain,whereas EA can prevent pain transition by decreasing the number of mast cells in the local tissue.展开更多
Mesenchymal stromal/stem cells(MSCs)have shown significant therapeutic potential,and have therefore been extensively investigated in preclinical studies of regenerative medicine.However,while MSCs have been shown to b...Mesenchymal stromal/stem cells(MSCs)have shown significant therapeutic potential,and have therefore been extensively investigated in preclinical studies of regenerative medicine.However,while MSCs have been shown to be safe as a cellular treatment,they have usually been therapeutically ineffective in human diseases.In fact,in many clinical trials it has been shown that MSCs have moderate or poor efficacy.This inefficacy appears to be ascribable primarily to the heterogeneity of MSCs.Recently,specific priming strategies have been used to improve the therapeutic properties of MSCs.In this review,we explore the literature on the principal priming approaches used to enhance the preclinical inefficacy of MSCs.We found that different priming strategies have been used to direct the therapeutic effects of MSCs toward specific pathological processes.Particularly,while hypoxic priming can be used primarily for the treatment of acute diseases,inflammatory cytokines can be used mainly to prime MSCs in order to treat chronic immune-related disorders.The shift in approach from regeneration to inflammation implies,in MSCs,a shift in the production of functional factors that stimulate regenerative or anti-inflammatory pathways.The opportunity to fine-tune the therapeutic properties of MSCs through different priming strategies could conceivably pave the way for optimizing their therapeutic potential.展开更多
Peltophorum dubium seeds provided by Anhembi, SP were scarified in 98% H2SO4 for 15 min to overcome mechani-cal dormancy. Seeds were primed in solutions of 0.2% Captan at 10 C and 27C, PEG 6000 -1.0 MPa at 10C and 27...Peltophorum dubium seeds provided by Anhembi, SP were scarified in 98% H2SO4 for 15 min to overcome mechani-cal dormancy. Seeds were primed in solutions of 0.2% Captan at 10 C and 27C, PEG 6000 -1.0 MPa at 10C and 27C, 0.5 mol KNO3, 0.75 Mol KNO3, 1.0 Mol KNO3. Eight treatments including the primed seeds and nonprimed seeds, five replicates with 100 seeds for each treatment, were set to 15-cm-Petri dish with double filter paper moistened with testing solution PEG in refrigerator at 27C. For the experiments of all the groups, osmotic potential were 0.0, -0.2, -0.4, -0.6, -0.8, -1.0, -1.2, and -1.4 MPa. P. dubium seeds were also set to water stress experiment in rolled paper with PEG solutions from 0.0 to -1.0 M Pa. Germination percentage decreased with the increase of PEG concentration. Control group had a better germination percentage than other groups. Germination hardly occurred in PEG -1.4 MPa.展开更多
Anticipated more frequent extreme events due to changes in global climatic variability requires adaptation of crop species to multi-occurrence abiotic stresses hereby sustaining the food security. Priming, by pre-expo...Anticipated more frequent extreme events due to changes in global climatic variability requires adaptation of crop species to multi-occurrence abiotic stresses hereby sustaining the food security. Priming, by pre-exposure of plants to an eliciting factor, enables plants to be more tolerant to later biotic or abiotic stress events. Priming induced “stress memory” exists in both present generation and the offspring. Thus, priming is suggested to be a promising strategy for plants to cope with the abiotic stresses under global change scenarios. In this review, the underlying physiological and molecular mechanisms of priming induced enhancement of stress tolerance to the major abiotic stresses of drought and waterlogging, and high and low temperature in crop plants were discussed, and the potential to utilize the priming effect for sustaining crop productivity in future climates was also suggested.展开更多
This study examined the influence of semantic and phonological priming on L2 speech planning,as well as the difference between native and non-native speakers of English in terms of lemma activation.Two potential expla...This study examined the influence of semantic and phonological priming on L2 speech planning,as well as the difference between native and non-native speakers of English in terms of lemma activation.Two potential explanations for the contrast between the performance of L2 speakers and native controls were considered.The first of which was that L2 speakers’ phonological forms are activated before selection of syntactic frame occurred,whereas the reverse is true for native speakers.The second explanation posits that the organisation of the speech production procedure is fundamentally similar in native and L2 speakers,and the disparity in performance arises from difference in the levels of activation of stored items.The results of the present experiment suggest that lemma selection is indeed what drives syntactic frame selection.However,lemmas in L2 speakers can be primed through a chain of connections demonstrated as:L2 phonological form →L1 phonological form → L1 lemma.展开更多
The effects of different priming treatments and priming durations on germination percentage at different temperatures in parsley seeds were studied. The seeds were treated for 2, 4, 6 and 8 days with the PEG 6000 (–0...The effects of different priming treatments and priming durations on germination percentage at different temperatures in parsley seeds were studied. The seeds were treated for 2, 4, 6 and 8 days with the PEG 6000 (–0.5 MPa, –1.0 MPa and –1.5 MPa), KNO3 (0.30 mol/L and 0.35 mol/L), Mannitol (0.50 mol/L and 0.60 mol/L) and hydropriming (12h, 24h, 36h and 48h) and unprimed (control). Germination studies were made at 5, 10, 15, 20 and 25°C. Percentage of germination at different temperatures was significantly affected by priming treatments. Hydropriming (12h, 24h and 36 h) and mannitol 0.60 mol/L at 2 day generally had the highest germination percentages. In general, the highest germination percentage with priming was determined at 10°C. It may be said that seed priming treatments increased seed germination percentage at both low and high temperatures. The highest germination percentages were observed in both hydropriming and mannitol treatments as compared with PEG and KNO3 treatments. The PEG and KNO3 (2 and 4 days) treatments were better than unprimed treatment in all of the temperatures.展开更多
Tolerance to water and salt stress during germination and growth of agricultural species might have superior results when seeds are submitted to priming processes. The objective of the present study was to evaluate th...Tolerance to water and salt stress during germination and growth of agricultural species might have superior results when seeds are submitted to priming processes. The objective of the present study was to evaluate the use of hydropriming and hormonal priming with gibberellic acid (GA3) on the tolerance of divergent genotypes of sorghum to salt and water stress during germination and seedling growth. The genotypes analyzed were cultivar BRS 330 and lineage 201420, which are the most and least tolerant to water and salt stress, respectively. Sowing was undertaken under control (no stress), water stress (-0.6 MPa), and salt stress (20 dS·m-1) conditions, and the seeds were subjected to the following treatments: control-no immersion;hydropriming-immersion for 2 hours in distilled water;and hormonal priming-immersion in GA3 solutions, at concentrations of 50, 75, and 100 ppm, for 2 hours. After soaking, the seeds were dried for 24 hours at a temperature of 30°C ± 2°C. The variables analyzed were percentage and germination speed index, root and shoot lengths, and root/shoot ratio. The stress conditions analyzed negatively affected the two genotypes;however, the seeds that underwent priming processes improved the performance of the genotypes under salt and water stress conditions, especially when using seeds of the more tolerant genotype (BRS 330) subjected to hormonal priming at 100 ppm GA3 concentration.展开更多
Low temperature stress during germination and early seedling growth is an important constraint of global production of maize. The effects of seed priming with 0.25%, 0.50%, and 0.75% （w/v） chitosan solutions at 15 ...Low temperature stress during germination and early seedling growth is an important constraint of global production of maize. The effects of seed priming with 0.25%, 0.50%, and 0.75% （w/v） chitosan solutions at 15 ℃ on the growth and physiological changes were investigated using two maize （Zea rnays L.） inbred lines, HuangC （chilling-tolerant） and Mo17 （chilling-sensitive）. While seed priming with chitosan had no significant effect on germination percentage under low temperature stress, it enhanced germination index, reduced the mean germination time （MGT）, and increased shoot height, root length, and shoot and root dry weights in both maize lines. The decline of malondialdehyde （MDA） content and relative permeability of the plasma membrane and the increase of the concentrations of soluble sugars and proline, peroxidase （POD） activity, and catalase （CAT） activity were detected both in the chilling-sensitive and chilling-tolerant maize seedlings after priming with the three concentrations of chitosan. HuangC was less sensitive to responding to different concentrations of chitosan. Priming with 0.50% chitosan for about 60-64 h seemed to have the best effects. Thus, it suggests that seed priming with chitosan may improve the speed of germination of maize seed and benefit for seedling growth under low temperature stress.展开更多
Low germination and vigor of rice seed associated with dry-seed broadcasting are common problems encountered by rice growers.The objectives of this study were to evaluate the role of potassium nitrate（KNO3）on the pa...Low germination and vigor of rice seed associated with dry-seed broadcasting are common problems encountered by rice growers.The objectives of this study were to evaluate the role of potassium nitrate（KNO3）on the pattern of seed imbibition and to determine the effect of seed priming with KNO3 on the germination percentage,speed and uniformity of germination in rice seed.Experiment 1 compared the patterns of seed imbibition of six concentrations of KNO3（0,0.25,0.50,1.00,1.50,and 2.00%）in two rice cultivars-KDML105 and RD15.The results showed that soaking rice seed in KNO3 at higher concentrations could delay the imbibition time.The higher concentrations of KNO3 delayed the imbibition time of rice seed and took a longer time to reach the end of phases 1 and 2 compared to the lower concentrations.The patterns of seed imbibition using distilled water of both rice cultivars（KDML105 and RD15）were quite similar,but with different concentrations of KNO3,the imbibition time taken to reach the end of phases 1 and 2 was slightly postponed in KDML105 suggesting that different rice cultivars may need different imbibition times for soaking seed in the priming process.Experiment 2 evaluated the effects of seed priming with 1.0 and 2.0%KNO3 at different imbibition times.It was found that priming with 1.0%KNO3 showed better seed germination than priming with 2.0%KNO3 and seed priming with 1.0%KNO3 at the imbibition time of early phase 2（or 28 h for KDML105）improved seed germination and increased both the speed and uniformity of seed germination.The results of this study show promise for the use of priming with 1.0%KNO3 soaked until early phase 2 of seed imbibition for improving the seed germination and vigor of rice in dry seed broadcasting.展开更多
Drought stress is a limiting factor for wheat production and food security.Drought priming has been shown to increase drought tolerance in wheat.However,the underlying mechanisms are unknown.In the present study,the g...Drought stress is a limiting factor for wheat production and food security.Drought priming has been shown to increase drought tolerance in wheat.However,the underlying mechanisms are unknown.In the present study,the genes encoding the biosynthesis and metabolism of abscisic acid(ABA)and jasmonic acid(JA),as well as genes involved in the ABA and JA signaling pathways were up-regulated by drought priming.Endogenous concentrations of JA and ABA increased following drought priming.The interplay between JA and ABA in plant responses to drought priming was further investigated using inhibitors of ABA and JA biosynthesis.Application of fluridone(FLU)or nordihydroguaiaretic acid(NDGA)to primed plants resulted in lower chlorophyll-fluorescence parameters and activities of superoxide dismutase and glutathione reductase,and higher cell membrane damage,compared to primed plants(PD)under drought stress.NDGA+ABA,but not FLU+JA,restored priming-induced tolerance,as indicated by a finding of no significant difference from PD under drought stress.Under drought priming,NDGA induced the suppression of ABA accumulation,while FLU did not affect JA accumulation.These results were consistent with the expression of genes involved in the biosynthesis of ABA and JA.They suggest that ABA and JA are required for priming-induced drought tolerance in wheat,with JA acting upstream of ABA.展开更多
基金National Natural Science Foundation of China(3216045632360474+2 种基金32360486)grants from the Provincial Basic Research Program(Natural Science)([2020]1Z018)Provincial Key Technology R&D Program([2021]YiBan272).
文摘Seed priming is an effective seed pretreatment technology that enhances germination and overall crop performance by optimizing seed hydration and metabolic processes before planting.Seed quality is a critical determinant of cotton(Gossypium hirsutum)crop performance,influencing germination,plant vigor,and yield.This study evaluates the effects of seed priming with potassium salts(1%and 2%KCl and K2SO4)on germination,morphological traits,and Cry1Ac gene expression in three Bt cotton cultivars(IUB-2013,NIAB-878B,FH-142)as Cry1Ac enhance the pest resistance in Bt cotton and reduce the plant’s dependence on chemical insecticides.Seeds were primed for six hours,air-dried,and sown in the field.Germination rates,plant height,number of bolls per plant,boll weight,seed cotton yield,and ginning outturn(GOT)were assessed at crop maturity.Cry1Ac gene expression was quantified to explore the influence of priming treatments on transgene activity.Results demonstrated that 1%K2SO4 priming significantly enhanced germination and yield-related traits,with Cry1Ac expression peaking in the IUB-2013 cultivar under 1%K2SO4 treatment.These findings suggest that potassium-based halopriming improves cotton seedling establishment and Bt gene expression.This study addresses the critical gaps in understanding the effects of seed halopriming on morphological traits,germination,and expression of the Cry1Ac gene in Bt cotton while providing a novel eco-friendly and cost-effective halopriming approach,offering the potential to improve cotton production.
基金supported by the projects of the National Key Research and Development Program of China(2023YFD2300202)the Natural Science Foundation of Jiangsu Province,China(BK20241543)+5 种基金the National Natural Science Foundation of China(32272213,32030076,U1803235,and 32021004)the Fundamental Research Funds for the Central Universities,China(XUEKEN2023013)the Jiangsu Innovation Support Program for International Science and Technology Cooperation Project,China(BZ2023049)the Jiangsu Agriculture Science and Technology Innovation Fund,China(CX(22)1006)the China Agriculture Research System(CARS-03)the Jiangsu Collaborative Innovation Center for Modern Crop Production,China(JCIC-MCP)。
文摘Frequent drought events severely restrict global crop productivity,especially those occurring in the reproductive stages.Moderate drought priming during the earlier growth stages is a promising strategy for allowing plants to resist recurrent severe drought stress.However,the underlying mechanisms remain unclear.Here,we subjected wheat plants to drought priming during the vegetative growth stage and to severe drought stress at 10 days after anthesis.We then collected leaf samples at the ends of the drought priming and recovery periods,and at the end of drought stress for transcriptome sequencing in combination with phenotypic and physiological analyses.The drought-primed wheat plants maintained a lower plant temperature,with higher stomatal openness and photosynthesis,thereby resulting in much lower 1,000-grain weight and grain yield losses under the later drought stress than the non-primed plants.Interestingly,416 genes,including 27 transcription factors(e.g.,MYB,NAC,HSF),seemed to be closely related to the improved drought tolerance as indicated by the dynamic transcriptome analysis.Moreover,the candidate genes showed six temporal expression patterns and were significantly enriched in several stress response related pathways,such as plant hormone signal transduction,starch and sucrose metabolism,arginine and proline metabolism,inositol phosphate metabolism,and wax synthesis.These findings provide new insights into the physiological and molecular mechanisms of the long-term effects of early drought priming that can effectively improve drought tolerance in wheat,and may provide potential approaches for addressing the challenges of increasing abiotic stresses and securing food safety under global warming scenarios.
基金supported by the projects of the National Key Research and Development Program of China (2023YFD2300202)the National Natural Science Foundation of China (32272213 and 31771693)+1 种基金the China Agriculture Research System (CARS-03)the Jiangsu Collaborative Innovation Center for Modern Crop Production, China (JCIC-MCP)。
文摘The impacts of drought stress on crop yield and quality are substantial. Drought priming during the early growth stage of plants has been shown to improve tolerance to drought stress during the reproductive stage, although its effects on grain quality remain elusive. This study investigated the influence of drought priming on starch and protein levels in grains under drought stress during grain filling. Our results revealed that drought stress leads to a reduction in the contents of starch and its constituents, while simultaneously increasing glutenin macropolymers and protein fractions. Notably, drought primed plants under drought stress(PD) exhibited mitigated declines in the contents of starch and its components, leading to improvements in starch swelling power and pasting properties. In addition, PD resulted in a slight increase in the protein fractions, limiting the overall rise in total protein content compared to drought stress alone. The results of our study underscore the efficacy of drought priming as a strategy to counteract the negative effects of drought stress on grain quality, particularly by minimizing starch losses and restraining protein content elevation.
基金supported by the Youth Talent Program of Fujian Academy of Agricultural Sciences,China(No.YC2019006)the External Cooperation Program of Fujian Academy of Agricultural Sciences,China(No.DWHZ-2022-20)+5 种基金the Foundation of Fujian Academy of Agricultural Sciences,China(No.CXTD2021012-2)the Special Fund of Fundamental Scientific Research at Nonprofit Research Institutions in Fujian,China(No.2022R1025001)the Special Fund of Fundamental Scientific Research at Nonprofit Research Institutions in Fujian,China(No.2022R1025001)the Natural Science Foundation of Fujian Province,China(No.2020J011358)the Modern Agro-Industry Technology Research System-Green Manure,China(No.CARS-22-G-01)“5511”Collaborative Innovation Engineering,China(No.XTCXGC2021009)。
文摘Nitrogen(N)priming is a microbially mediated biochemical process as affected by different incorporation practices.However,little information is known about the microbial mechanisms driving the response of N priming to co-operation of Chinese milk vetch(CMV,Astragalus sinicus L.)and different rates of chemical fertilizers in paddy soils in South China.Here,an anaerobic incubation experiment was conducted to study N priming effects(PE)and their relationships with soil microbial functional genes after CMV incorporation alone(M),co-incorporation of CMV with 100%(normal dosage)chemical fertilizers(MC100),and co-incorporation of CMV with 80% chemical fertilizers(MC80).Co-incorporation of CMV and chemical fertilizers enhanced the short-time scale(the first 20 d of incubation)positive PE of N,while no significant differences existed among the three treatments on day 60 or 90 of incubation(P>0.05).Compared with the M treatment,gross priming effect(GPE)in the MC100 and MC80 treatments significantly increased by 34.0% and 31.3%,respectively,and net priming effect(NPE)increased by 47.7% and 47.8%,respectively,during the first 20 d of incubation(P<0.05).This was likely attributed to soil nutrient availability and added substrate quality.The MC100 and MC80 treatments increased the gdhA gene abundance by 5.0% and 9.8%,increased the gdh2 gene abundance by 12.7% and 45.7%,and increased the nasB gene abundance by 9.5% and 41.4%,respectively,in comparison with the M treatment on day 20 of incubation.Correlation analyses indicated that soil microbial functional genes involved in N mineralization(gdhA and gdh2),assimilatory nitrate reduction(nasB),and nitrification(amoB)were significantly correlated with N priming under different incorporation practices during the incubation period(P<0.05).Thus,co-incorporation of CMV and chemical fertilizers can regulate soil microbial community functional gene structure,which may accelerate mineralization and assimilatory nitrate reduction and inhibit nitrification,thereby increasing the short-term positive PE of N in the present study.
文摘Stem cell expansion in vitro and transplantation in the cytokine-rich proinflammatory milieu in the injured tissue generate immense oxidative stress that interferes with the cells’survival,stemness,and repairability.Stem cell priming has gained popularity to overcome these issues.Given melatonin’s oxidative-scavenging properties,Gu et al have used periodontal ligament stem cells cultured under oxidative stress as an in vitro model to study the cytoprotective effects of melatonin.Our letter to the editor delves into melatonin-induced stem cell priming and the underlying molecular mechanism,focusing on the intriguing role of Yesassociated protein signaling in alleviating oxidative stress.We stress the importance of understanding the distinction between in vitro and in vivo oxidative stress conditions,a crucial aspect of stem cell research that invokes a sense of critical thinking in the readership.The study by Gu et al presents a novel approach to oxidative stress management,offering exciting possibilities for future research and applications.
文摘Mesenchymal stromal/stem cells(MSCs)have garnered significant attention in the field of regenerative medicine due to their remarkable therapeutic potential.MSCs play a pivotal role in maintaining tissue homeostasis and possess diverse functions in tissue repair and recovery in various organs.These cells are charac-terized by easy accessibility,few ethical concerns,and adaptability to in vitro cultures,making them a valuable resource for cell therapy in several clinical conditions.Over the years,it has been shown that the true therapeutic power of MSCs lies not in cell engraftment and replacement but in their ability to produce critical paracrine factors,including cytokines,growth factors,and exosomes(EXOs),which modulate the tissue microenvironment and facilitate repair and regeneration processes.Consequently,MSC-derived products,such as condi-tioned media and EXOs,are now being extensively evaluated for their potential medical applications,offering advantages over the long-term use of whole MSCs.However,the efficacy of MSC-based treatments varies in clinical trials due to both intrinsic differences resulting from the choice of diverse cell sources and non-standardized production methods.To address these concerns and to enhance MSC therapeutic potential,researchers have explored many priming strategies,including exposure to inflammatory molecules,hypoxic conditions,and three-dimensional culture techniques.These approaches have optimized MSC secretion of functional factors,empowering them with enhanced immunomodulatory,angiogenic,and regenerative properties tailored to specific medical conditions.In fact,various priming strategies show promise in the treatment of numerous diseases,from immune-related disorders to acute injuries and cancer.Currently,in order to exploit the full therapeutic potential of MSC therapy,the most important challenge is to optimize the modulation of MSCs to obtain adapted cell therapy for specific clinical disorders.In other words,to unlock the complete potential of MSCs in regenerative medicine,it is crucial to identify the most suitable tissue source and develop in vitro manipulation protocols specific to the type of disease being treated.
基金The authors are very much grateful to Bangladesh Agricultural University Research System(BAURES)Bangladesh Agricultural University,Mymensingh-2202,Bangladesh for the financial support through the research project entitled“Induction of Heat and Drought Tolerance in Wheat through Seed Priming”(Project No.2021/35/BAU)to carry out the research work.
文摘Seed priming is a pre-germinated technique that can enhance seed germination percentage,faster and synchro-nized germination,better seedling growth,and yield under stress conditions.To ascertain the most effective seed priming method that would ensure the potential yield of wheat in Bangladesh,two experiments were carried out from December 2021 to March 2022 at the Department of Agronomy,Bangladesh Agricultural University.Two wheat varieties namely BARI Gom-28 and BWMRI Gom-1 were subjected to a range of priming chemicals in both lab and pot tests.These compounds included the following:control(no priming),hydropriming(distilled water),10000 ppm KNO_(3),15000 ppm KNO_(3),40000 ppm Mannitol,60000 ppm Mannitol,10000 ppm NaCl,20000 ppm NaCl,100 ppm PEG,150 ppm PEG,500 ppm NaOCl,1000 ppm NaOCl,10000 ppm CaCl_(2),20000 ppm CaCl_(2),10000 ppm KCl and 20000 ppm KCl.A complete randomized design(CRD)with three repli-cations was used to set up the experiments.The results showed that BARI Gom-28 and BWMRI Gom-1 responded best to KCl priming in terms of rapid seed germination and strong seedling development.On the other hand,the best priming agents for plant growth and productivity turned out to be CaCl_(2) and KCL.The results of this study support the possibility of using seed priming as a technique to improve wheat plant development and output by raising seed emergence and survival rates.
文摘Chilling is one of the major abiotic stresses for plants,especially for rice cultivation.Many essential metabolic processes for growth and development are temperature-dependent.In that case,reducing the negative effects of cold stress using exogenous chemicals is a possible option.Therefore,the current study examined the effects of pre-sowing seed treatment with different chemicals,viz.hydrogen peroxide(H_(2)O_(2)),salicylic acid(SA),calcium chloride(CaCl_(2)),thiourea(TU),and citric acid(CA)on the germination of rice seeds(cv.BRRI dhan28)under chilling environments.Rice seeds were soaked in distilled water(control),10 mM CA,2 mM SA,10 mM CaCl_(2),10 mM H_(2)O_(2),and 10 mM TU solutions for 24 h.After that,seeds were exposed to chilling stress by incubating at 4±1℃ for 8 h,followed by at 25±2℃ for 16 h for 7 days.Exposure to chilling stress significantly reduced thefinal germination percent(13.6%),germination rate index(36.0%),coefficient of the velocity(25.0%),shoot fresh weight(44.4%),and root fresh weight(60.5%).Moreover,chilling induced oxidative damage and reduced the activity of antioxidant enzymes(catalase and ascorbate peroxidase).In contrast,treatments with H_(2)O_(2),SA,CaCl_(2),TU,and CA considerably enhanced germination indices and seedling growth compared to chilling stress condi-tions.The study showed that priming with H_(2)O_(2),SA,CaCl_(2),TU,and CA significantly boosted antioxidant enzyme activities and reduced MDA and H_(2)O_(2) contents in chilling-stressed rice plants,indicating less oxidative stress and improved tolerance.Principal component analysis showed that among these priming agents,H_(2)O_(2),SA,and CA are most effective in chilling stress mitigation.Therefore,using seed-treating chemicals to combat the effect of chilling stress can help rice seedlings grow better in the winter season.
基金the Zhejiang Provincial Natural Science Fund of China(LY24H270003)the National Natural Science Fund of China(82174490,82374561)+1 种基金the Zhejiang Medical and Health Science and Technology Program(2021RC098)the Research Project of Zhejiang Chinese Medical University(2022JKZKTS44).
文摘Objective:Injury can lead to long-term changes that increase the sensitivity of afferent nerve endings to subsequent stimulation and pain can transition from acute to chronic.This phenomenon is known as hyperalgesic priming(HP).This study aimed to understand the mechanisms underlying the effect of electroacupuncture(EA)on HP and optimize acupoint selection for EA to prevent pain transition.Methods:A rat HP model was established using sequential intraplantar injections of carrageenan(Cg)and prostaglandin E2(PGE2).The pain thresholds were measured using von Frey filaments.EA on bilateral Zusanli(ST36)and Kunlun(BL60)was used to prevent pain transition.The number of mast cells in the ipsilateral hindpaw skin was determined using toluidine blue or fluorescencelabeled avidin staining.The protein expression levels of protein kinase C epsilon(PKCε)in the lumbar dorsal root ganglions(DRGs)were detected by western blotting 24 h after PGE2 injection.Serial pharmacological experiments were conducted to evaluate the relationship between mast cells and pain transition.Finally,EA on the bilateral ST36 and Chongyang(ST42)or a novel combination(ST36 and ST42 on the ipsilateral side,and ST36 and BL60 on the contralateral side)was used to prevent pain transition.Results:Although EA applied to ST36 and BL60 alleviated acute pain induced by Cg injection,it failed to prevent the pain transition caused by PGE2 injection.Mast cell accumulation in the ipsilateral hind paw was observed 7 days after Cg injection.Furthermore,mast cell degranulation may be responsible for PKCεactivation in the DRG,a marker of pain transition.EA significantly decreased the number of mast cells in the skin of the ipsilateral hind paw when applied at ST36 and ST42,but not when applied at ST36 and BL60.Furthermore,EA employed to ST36 and ST42 significantly reversed long-term hyperalgesia induced by PGE2 injection,even when administered before injection.However,EA did not alleviate acute pain caused by Cg injection.By using a novel acupoint combination,EA simultaneously alleviated acute pain and prevented pain transition.Conclusions:Our study suggests that mast cells play a critical role in both HP and the transition from acute to chronic pain,whereas EA can prevent pain transition by decreasing the number of mast cells in the local tissue.
文摘Mesenchymal stromal/stem cells(MSCs)have shown significant therapeutic potential,and have therefore been extensively investigated in preclinical studies of regenerative medicine.However,while MSCs have been shown to be safe as a cellular treatment,they have usually been therapeutically ineffective in human diseases.In fact,in many clinical trials it has been shown that MSCs have moderate or poor efficacy.This inefficacy appears to be ascribable primarily to the heterogeneity of MSCs.Recently,specific priming strategies have been used to improve the therapeutic properties of MSCs.In this review,we explore the literature on the principal priming approaches used to enhance the preclinical inefficacy of MSCs.We found that different priming strategies have been used to direct the therapeutic effects of MSCs toward specific pathological processes.Particularly,while hypoxic priming can be used primarily for the treatment of acute diseases,inflammatory cytokines can be used mainly to prime MSCs in order to treat chronic immune-related disorders.The shift in approach from regeneration to inflammation implies,in MSCs,a shift in the production of functional factors that stimulate regenerative or anti-inflammatory pathways.The opportunity to fine-tune the therapeutic properties of MSCs through different priming strategies could conceivably pave the way for optimizing their therapeutic potential.
基金This work is Supported by CAPES Brazil. Open research laboratory of forest plant ecology NEFU. The State's tenth five-year "211 Project"-supported key academic discipline program of ECNU。
文摘Peltophorum dubium seeds provided by Anhembi, SP were scarified in 98% H2SO4 for 15 min to overcome mechani-cal dormancy. Seeds were primed in solutions of 0.2% Captan at 10 C and 27C, PEG 6000 -1.0 MPa at 10C and 27C, 0.5 mol KNO3, 0.75 Mol KNO3, 1.0 Mol KNO3. Eight treatments including the primed seeds and nonprimed seeds, five replicates with 100 seeds for each treatment, were set to 15-cm-Petri dish with double filter paper moistened with testing solution PEG in refrigerator at 27C. For the experiments of all the groups, osmotic potential were 0.0, -0.2, -0.4, -0.6, -0.8, -1.0, -1.2, and -1.4 MPa. P. dubium seeds were also set to water stress experiment in rolled paper with PEG solutions from 0.0 to -1.0 M Pa. Germination percentage decreased with the increase of PEG concentration. Control group had a better germination percentage than other groups. Germination hardly occurred in PEG -1.4 MPa.
基金supported by the National Key Research andDevelopment Program of China (2016YFD0300107)the National Natural Science Foundation of China (31325020, 31401326, 31471445, 31771693)+3 种基金the earmarked fund for China Agriculture Research System (CARS-03)the Project funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions, Chinathe Fundamental Research Funds for the Central Universities, China (KJQN201505)the Jiangsu Collaborative Innovation Center for Modern Crop Production, China (JCIC-MCP)
文摘Anticipated more frequent extreme events due to changes in global climatic variability requires adaptation of crop species to multi-occurrence abiotic stresses hereby sustaining the food security. Priming, by pre-exposure of plants to an eliciting factor, enables plants to be more tolerant to later biotic or abiotic stress events. Priming induced “stress memory” exists in both present generation and the offspring. Thus, priming is suggested to be a promising strategy for plants to cope with the abiotic stresses under global change scenarios. In this review, the underlying physiological and molecular mechanisms of priming induced enhancement of stress tolerance to the major abiotic stresses of drought and waterlogging, and high and low temperature in crop plants were discussed, and the potential to utilize the priming effect for sustaining crop productivity in future climates was also suggested.
文摘This study examined the influence of semantic and phonological priming on L2 speech planning,as well as the difference between native and non-native speakers of English in terms of lemma activation.Two potential explanations for the contrast between the performance of L2 speakers and native controls were considered.The first of which was that L2 speakers’ phonological forms are activated before selection of syntactic frame occurred,whereas the reverse is true for native speakers.The second explanation posits that the organisation of the speech production procedure is fundamentally similar in native and L2 speakers,and the disparity in performance arises from difference in the levels of activation of stored items.The results of the present experiment suggest that lemma selection is indeed what drives syntactic frame selection.However,lemmas in L2 speakers can be primed through a chain of connections demonstrated as:L2 phonological form →L1 phonological form → L1 lemma.
文摘The effects of different priming treatments and priming durations on germination percentage at different temperatures in parsley seeds were studied. The seeds were treated for 2, 4, 6 and 8 days with the PEG 6000 (–0.5 MPa, –1.0 MPa and –1.5 MPa), KNO3 (0.30 mol/L and 0.35 mol/L), Mannitol (0.50 mol/L and 0.60 mol/L) and hydropriming (12h, 24h, 36h and 48h) and unprimed (control). Germination studies were made at 5, 10, 15, 20 and 25°C. Percentage of germination at different temperatures was significantly affected by priming treatments. Hydropriming (12h, 24h and 36 h) and mannitol 0.60 mol/L at 2 day generally had the highest germination percentages. In general, the highest germination percentage with priming was determined at 10°C. It may be said that seed priming treatments increased seed germination percentage at both low and high temperatures. The highest germination percentages were observed in both hydropriming and mannitol treatments as compared with PEG and KNO3 treatments. The PEG and KNO3 (2 and 4 days) treatments were better than unprimed treatment in all of the temperatures.
文摘Tolerance to water and salt stress during germination and growth of agricultural species might have superior results when seeds are submitted to priming processes. The objective of the present study was to evaluate the use of hydropriming and hormonal priming with gibberellic acid (GA3) on the tolerance of divergent genotypes of sorghum to salt and water stress during germination and seedling growth. The genotypes analyzed were cultivar BRS 330 and lineage 201420, which are the most and least tolerant to water and salt stress, respectively. Sowing was undertaken under control (no stress), water stress (-0.6 MPa), and salt stress (20 dS·m-1) conditions, and the seeds were subjected to the following treatments: control-no immersion;hydropriming-immersion for 2 hours in distilled water;and hormonal priming-immersion in GA3 solutions, at concentrations of 50, 75, and 100 ppm, for 2 hours. After soaking, the seeds were dried for 24 hours at a temperature of 30°C ± 2°C. The variables analyzed were percentage and germination speed index, root and shoot lengths, and root/shoot ratio. The stress conditions analyzed negatively affected the two genotypes;however, the seeds that underwent priming processes improved the performance of the genotypes under salt and water stress conditions, especially when using seeds of the more tolerant genotype (BRS 330) subjected to hormonal priming at 100 ppm GA3 concentration.
基金Project supported by the Major Science and Technology Special Project (priority subject) of Zhejiang Province (No. 2008C12005-1)the Key Project of Education Department of Zhejiang Province (No. 20070147), China
文摘Low temperature stress during germination and early seedling growth is an important constraint of global production of maize. The effects of seed priming with 0.25%, 0.50%, and 0.75% （w/v） chitosan solutions at 15 ℃ on the growth and physiological changes were investigated using two maize （Zea rnays L.） inbred lines, HuangC （chilling-tolerant） and Mo17 （chilling-sensitive）. While seed priming with chitosan had no significant effect on germination percentage under low temperature stress, it enhanced germination index, reduced the mean germination time （MGT）, and increased shoot height, root length, and shoot and root dry weights in both maize lines. The decline of malondialdehyde （MDA） content and relative permeability of the plasma membrane and the increase of the concentrations of soluble sugars and proline, peroxidase （POD） activity, and catalase （CAT） activity were detected both in the chilling-sensitive and chilling-tolerant maize seedlings after priming with the three concentrations of chitosan. HuangC was less sensitive to responding to different concentrations of chitosan. Priming with 0.50% chitosan for about 60-64 h seemed to have the best effects. Thus, it suggests that seed priming with chitosan may improve the speed of germination of maize seed and benefit for seedling growth under low temperature stress.
基金financially supported by a Kasetsart University 72 Year Anniversary Graduate Scholarship, from the Graduate School, Kasetsart University, Thailand
文摘Low germination and vigor of rice seed associated with dry-seed broadcasting are common problems encountered by rice growers.The objectives of this study were to evaluate the role of potassium nitrate（KNO3）on the pattern of seed imbibition and to determine the effect of seed priming with KNO3 on the germination percentage,speed and uniformity of germination in rice seed.Experiment 1 compared the patterns of seed imbibition of six concentrations of KNO3（0,0.25,0.50,1.00,1.50,and 2.00%）in two rice cultivars-KDML105 and RD15.The results showed that soaking rice seed in KNO3 at higher concentrations could delay the imbibition time.The higher concentrations of KNO3 delayed the imbibition time of rice seed and took a longer time to reach the end of phases 1 and 2 compared to the lower concentrations.The patterns of seed imbibition using distilled water of both rice cultivars（KDML105 and RD15）were quite similar,but with different concentrations of KNO3,the imbibition time taken to reach the end of phases 1 and 2 was slightly postponed in KDML105 suggesting that different rice cultivars may need different imbibition times for soaking seed in the priming process.Experiment 2 evaluated the effects of seed priming with 1.0 and 2.0%KNO3 at different imbibition times.It was found that priming with 1.0%KNO3 showed better seed germination than priming with 2.0%KNO3 and seed priming with 1.0%KNO3 at the imbibition time of early phase 2（or 28 h for KDML105）improved seed germination and increased both the speed and uniformity of seed germination.The results of this study show promise for the use of priming with 1.0%KNO3 soaked until early phase 2 of seed imbibition for improving the seed germination and vigor of rice in dry seed broadcasting.
基金supported by the National Key Research and Development Program of China(2016YFD0300107)the National Natural Science Foundation of China(31771693,U1803235)+3 种基金the Fundamental Research Funds for the Central Universities(KYZ201807)the China Agricultural Research System(CARS-03)the Jiangsu Collaborative Innovation Center for Modern Crop Production(JCIC-MCP)the 111 Project(B16026)。
文摘Drought stress is a limiting factor for wheat production and food security.Drought priming has been shown to increase drought tolerance in wheat.However,the underlying mechanisms are unknown.In the present study,the genes encoding the biosynthesis and metabolism of abscisic acid(ABA)and jasmonic acid(JA),as well as genes involved in the ABA and JA signaling pathways were up-regulated by drought priming.Endogenous concentrations of JA and ABA increased following drought priming.The interplay between JA and ABA in plant responses to drought priming was further investigated using inhibitors of ABA and JA biosynthesis.Application of fluridone(FLU)or nordihydroguaiaretic acid(NDGA)to primed plants resulted in lower chlorophyll-fluorescence parameters and activities of superoxide dismutase and glutathione reductase,and higher cell membrane damage,compared to primed plants(PD)under drought stress.NDGA+ABA,but not FLU+JA,restored priming-induced tolerance,as indicated by a finding of no significant difference from PD under drought stress.Under drought priming,NDGA induced the suppression of ABA accumulation,while FLU did not affect JA accumulation.These results were consistent with the expression of genes involved in the biosynthesis of ABA and JA.They suggest that ABA and JA are required for priming-induced drought tolerance in wheat,with JA acting upstream of ABA.
