Seed viability of 18 576 accessions of 23 crops was monitored. After 10-12 years storage in National Crop Genebank ofChina (NCGC), more than 96.12% of the accessions maintained high germination percentage (>85%). T...Seed viability of 18 576 accessions of 23 crops was monitored. After 10-12 years storage in National Crop Genebank ofChina (NCGC), more than 96.12% of the accessions maintained high germination percentage (>85%). The germination of95 accessions, accounting for 0.51% of the total, declined significantly from above 80% to below 70%. For each crop ofcarrot (Daucus carota var. sativa DC.), lettuce (Lactuca sativa L.), cotton (Gossypium sp. L.), flax (Linum usitatissimumL.) and castor-oil plant (Ricinus communis L.), the mean monitored germination percentage declined significantly as awhole, of which carrot and lettuce seeds lost viability more rapidly. Seed initial germination percentage and pre-storageenvironments affect subsequent seed viability in storage.展开更多
This study aimed to observe the viability of the pollen grains of Malpighia emarginata DC. (West Indian cherry) and the action of a lectin in their germination. Lectins are proteins that specifically interact with car...This study aimed to observe the viability of the pollen grains of Malpighia emarginata DC. (West Indian cherry) and the action of a lectin in their germination. Lectins are proteins that specifically interact with carbohydrates, but don’t modify them and bind with high affinity and specificity, promoting a transfer of information that is clearly central to many cellular processes in living beings. For the viability test was used aniline blue in lactophenol. The in vitro germination test used was the hanging drop method, in control medium containing sucrose, boric acid, calcium nitrate and agar. The experiment dealt with three different treatments in order to pollen germination: growing medium without addition of lectin, with 1.0 μg/ml and with 3.0 μg/ml CPL lectin. This lectin is extracted from seeds of Crotalaria pallida L.-Leguminosae. Data on pollen grains were analyzed by one-way ANOVA, with 95% reliability and comparison of averages by Turkey test at 5% probability. It was found that despite previous high viability of the pollen grains (c. 70%), a germinability rate has been low, yet exceptionally larger in pollen samples placed on a growing medium with addition of 3.0 μg/ml of CPL lectin (24%). There was no significant difference among the pollen grains germinate in medium without lectin and those in medium with the addition of only 1.0 μg/ml. According to data obtained in the treatments, CPL lectin, with concentration of 3.0 μg/ml, influenced the formation of the pollen tube and thus more pollen germinated in Malpighia emarginata.展开更多
Ex situ conservation in seed banks is a potential complementary conservation strategy for native plant species.It is well established that ex situ seed banking of native wild plants prolongs seed viability and thereby...Ex situ conservation in seed banks is a potential complementary conservation strategy for native plant species.It is well established that ex situ seed banking of native wild plants prolongs seed viability and thereby preserves genetic and species diversity for future use.We evaluated ex situ storage potential of eight halophytic species from deserts in the United Arab Emirates(UAE)by studying seed germination.Specifically,we examined the germinability of freshly collected seeds and seeds stored for three years in a seed bank.We also examined the effect of light conditions on fresh and stored seed germination.Fresh seeds of seven of the eight species tested had a higher germination rates under 12/12 h light/dark fluctuations than did those exposed to total darkness.Storage reduced light sensitivity in Halocnemum strobilaceum,Suaeda aegyptiaca,Salsola drummondii and Salsola imbricata,but increased the requirement for light in Arthrocnemum macrostachyum.In Anabasis setifera,storage decreased germination percentage when there was a 12-hour light/dark fluctuation,but increased germination rate when exposed to the dark treatment.Storage significantly reduced germination in both the light/dark and dark treatments in Suaeda vermiculata and S.aegyptiaca.Germination speed also responded differently to storage;whereas Timson's index significantly increased in A.macrostachyum and H.strobilaceum,it significantly decreased for S.drummondii,S.aegyptiaca and S.vermiculata.Germination of these species at a range of temperatures requires further testing;additionally,we strongly suggest that these laboratory findings be complemented by field studies.展开更多
Strontium has similar chemical properties to calcium and has recently been recognized as a non-essential beneficial element for plants.In order to compare the effects of strontium and calcium on improving salt toleran...Strontium has similar chemical properties to calcium and has recently been recognized as a non-essential beneficial element for plants.In order to compare the effects of strontium and calcium on improving salt tolerance of Chinese cabbage during the germination stage,2,4,and 8 mmol/L of SrCl_(2),CaCl_(2) or an equimolar mixture of both were added separately to a 150 mmol/L NaCl solution.The results showed that Ca-Sr addition significantly increased seed viability,seed vigor,seed germination rate and seed germination uniformity of Chinese cabbage compared with the salt-control group.The differences in germination percentage(GP)and germination energy(GE)among the Ca-addition and Sr-addition groups were not significant,and the differences in coefficient of rate of germination(CRG),index of rate of germination(IRG)and coefficient of variation of the germination time(CVT)were relatively small,but clear differences were observed in germination index(GI),vigor index(VI)and coefficient of uniformity of germination(CUG).The results of GI and VI indicated that the higher the concentration of Ca-addition or Sr-addition,the more significant the enhancement of seed vigor.Under saline stress(150 mmol/L NaCl),the Ca-Sr co-addition outperformed Sr-treatment alone,and Ca-addition achieved the highest seed vigor at equivalent concentrations.Furthermore,all Ca-Sr treatments significantly enhanced the uniformity of Chinese cabbage sprouts exposed to 150 mM NaCl,with the best uniformity improved by the addition of 2 and 4 mmol/L SrCl_(2).Ca-Sr treatments increased the salt tolerance of Chinese cabbage sprouts during the germination stage mainly because the Ca2+and Sr2+significantly enhanced plasma membrane stability and reduced oxidative stress(as indicated by decreased contents of malondialdehyde and O2⋅-contents)in sprouts.The decrease of soluble sugar and proline content caused by Ca-Sr addition implies that elevated levels of these osmolytes were not the primary contributors to improved seed germinability in Chinese cabbage.These findings demonstrate that Sr is a beneficial element for enhancing salt tolerance in plants,laying a theoretical foundation for the development and application of strontium in agriculture.展开更多
A double haploid population, derived from anther culture of F, hybrid between a typical indica and a japonica (ZYQ8/JX17), has been used to investigate the low temperature germinability (LTG) at 15℃. The low temperat...A double haploid population, derived from anther culture of F, hybrid between a typical indica and a japonica (ZYQ8/JX17), has been used to investigate the low temperature germinability (LTG) at 15℃. The low temperature germinability of two parents was significantly different. In 6-11 d, the germination percentage of ZYQ8 was higher than that of JX17. In 12-16 d, the germination percentage of JX17 was higher than that of ZYQ8. The quantitative trait loci (QTLs) of every day for low temperature germinabilityhave been mapped based on a molecular linkage map constructed from this population. In 8-11 d, qLTG-9 was identified in C397B-RZ617B on chromosome 9, the additive effect was positive, showing that, the allele from JX17 could increase low temperature germinability. In 12-16 d, qLTG-4 was mapped between RG908 and CT563 on chromosome 4, the additive effect was negative, showing that the allele from ZYQ8 could increase low temperature germinability. These two QTLs were detected at different stages,展开更多
The oilseed crop Camelina sativa exhibits salinity tolerance,but the effects on early growth stages across a range of different salts and in combination with salicylic acid(SA)have not been thoroughly evaluated.In thi...The oilseed crop Camelina sativa exhibits salinity tolerance,but the effects on early growth stages across a range of different salts and in combination with salicylic acid(SA)have not been thoroughly evaluated.In this study,seeds were germinated in varying concentrations of six salts(NaCl,CaCl_(2),ZnCl_(2),KCl,MgSO_(4),and Na2SO_(4))with or without 0.5 mM SA.Using the halotime model,we estimated salt thresholds for germination and parameters of seedling growth.Germination and seedling growth parameters of camelina significantly decreased with increasing salt concentration across all salt types.Salts containing Zn and SO_(4) were most detrimental to germination and seedling growth.Except for KCl,0.5 mM SA generally reduced the salinity tolerance threshold(Saltb(50))of camelina.Specifically,Saltb(50)was 21.5%higher for KCl and 16.1%,25.0%,54.9%,21.0%,and 5.6%lower for CaCl_(2),NaCl,MgSO_(4),Na2SO_(4),and ZnCl_(2),respectively,when 0.5 mM SA was compared to 0 mM SA.Furthermore,camelina seedling growth was consistently more sensitive than germination across all salt types.SA did not significantly enhance germination or seedling growth and was harmful when combined with certain salts or at the germination stage.It can be concluded that both the type of salt and the concentration of SA are as critical as the salt concentration in saline irrigation water.展开更多
[Objectives]To identify the drought resistance of main wheat varieties in Shandong Province and screen suitable cultivars for dryland cultivation.[Methods]Employing eight varieties including Jimai 60 as test materials...[Objectives]To identify the drought resistance of main wheat varieties in Shandong Province and screen suitable cultivars for dryland cultivation.[Methods]Employing eight varieties including Jimai 60 as test materials,this study simulated drought stress using 20%PEG-6000 and measured changes in germination-stage indicators.A comprehensive evaluation was conducted using the membership function method,incorporating relative coleoptile length,relative germ length,relative radicle length,relative germination rate,relative germination potential,and stress germination index.[Results]Drought stress not only reduced wheat seed germination rate but also inhibited the growth of the germ,coleoptile,and radicle.The D values of the eight varieties were ranked as follows:Jimai 60>Linmai 9>Yannong 999>Shannong 30>Shannong 28>Luyuan 502>Yannong 1212>Jimai 22.Based on D values,the eight dominant wheat varieties were classified into three categories:highly drought-resistant varieties(Linmai 9 and Jimai 60),moderately drought-resistant varieties(Yannong 999 and Shannong 30),and sensitive varieties(the others).Linmai 9 and Jimai 60 are recommended as suitable wheat varieties for dryland cultivation in Shandong Province.[Conclusions]Drought stress induced by 20%PEG-6000 reduced germination rate,germination potential,and germination index of wheat varieties while inhibiting the growth of coleoptiles and radicles.These indicators can provide a preliminary assessment of drought resistance in wheat cultivars.However,since filter paper was selected as the growth medium,root length measurement errors were introduced during root washing,leading to variations in final experimental results.Futuer studies could attempt using sterilized sand as an alternative growth medium.展开更多
The present study examines the toxicological effects and bioaccumulation of strontium(Sr^(2+))in two Moroccan wheat species,Triticum durum(Nachit)and Triticum aestivum(Ibtissam).Germination rates and seedling growth p...The present study examines the toxicological effects and bioaccumulation of strontium(Sr^(2+))in two Moroccan wheat species,Triticum durum(Nachit)and Triticum aestivum(Ibtissam).Germination rates and seedling growth parameters were evaluated under Sr^(2+)concentrations of 0,10,100,and 1000 mM.Results revealed a significant decline in germination rates as Sr^(2+)concentrations increased,with T.aestivum showing higher sensitivity compared to T.durum.Low Sr^(2+)concentrations(10 mM)initially promoted stem growth in T.aestivum,but growth declined sharply at higher concentrations.Both species sustained growth at moderate Sr^(2+)concentrations(100 mM),but experienced a substantial reduction at 1000 mM,with T.durum demonstrating slightly better tolerance.Elevated Sr^(2+)concentrations notably affected root length and stem branching,indicating severe phytotoxic effects.Enzyme activity assays showed that at low Sr^(2+)concentration(10 mM),GST,CAT,POD,and SOD activities were similar to the control.At moderate concentrations(100 mM),GST and POD activities increased,suggesting enhanced detoxification.At high concentrations(1000 mM),all enzyme activities were significantly elevated,reflecting a robust antioxidative defense mechanism.This study provides valuable insights into the toxicological impacts and physiological responses of these wheat species to Sr^(2+)stress.展开更多
Roasting is important for improving the content of bioactive compounds and enhancing the flavor of flaxseed oil.However,the effect of roasting time on germinated flaxseed oil(GFO)is unclear.Herein,the influence of roa...Roasting is important for improving the content of bioactive compounds and enhancing the flavor of flaxseed oil.However,the effect of roasting time on germinated flaxseed oil(GFO)is unclear.Herein,the influence of roasting time(0–50 min)at a specific temperature of 160?C on the physicochemical properties,bioactive compounds,antioxidant capacity,and volatile compounds of GFO from three flaxseed varieties was examined.An extension in roasting time increased the a^(*)value of GFO,while the L^(*)and b^(*)values of GFO decreased.Higher chlorophylls(1.63±0.01–2.18±0.01 mg/kg),carotenoids(2.25±0.00–2.69±0.02 mg/kg),total phenolic content(156.75±2.93–200.03±6.29 mg GAE/kg),phytosterol(1801.93±30.64–1965.23±13.71 mg GAE/kg)and DPPH(320.11±18.22–432.19±14.95μmol TE/kg)and ABTS radical scavenging activity(810.68±16.29–1119.01±14.25μmol TE/kg)were detected in GFO after roasting for 20–30 min.However,the total tocopherol and unsaturated fatty acid content declined,and the composition of fatty acids changed insignificantly(P>0.05).GC–MS recognized 68 volatile compounds in GFO,in which pyrazine imparted a nutty flavor to the GFO.This study provides important information for the development of high-quality GFO.展开更多
Pinus koraiensis is the dominant and constructive species of the zonal vegetation in Northeast China,known as the mixed broadleaf-Korean pine forest.Although carbohydrate metabolism pathways in the seed embryo are kno...Pinus koraiensis is the dominant and constructive species of the zonal vegetation in Northeast China,known as the mixed broadleaf-Korean pine forest.Although carbohydrate metabolism pathways in the seed embryo are known to play crucial roles during seed dormancy and germination in P.koraiensis,it remains unclear whether these metabolic pathways function differentially across tissues.P.koraiensis seeds that had undergone different durations of moist chilling in their natural environment,yielding seeds with relatively deeper primary physiological dormancy(DDS)and seeds with released primary physiological dormancy(RDS).A non-targeted metabolomic analysis was conducted on the radicle and hypocotyl-cotyledon portions of both DDS and RDS,before and after a two-week incubation under favorable conditions.Under germination conditions,RDS and DDS showed divergent metabolic profiles,especially regarding carbohydrate metabolism.Specifically,RDS seeds showed significantly reduced substrates of respiratory metabolic pathways in both radicles and hypocotyl-cotyledons.Conversely,the intermediates of the carbohydrate metabolism pathway(particularly the tricarboxylic acid cycle)accumulating in radicles of DDS seeds under germination conditions.Moreover,in RDS,the carbohydrate metabolic pathways were more prevalent in the hypocotyl-cotyledon,while lysine degradation and ascorbate and aldarate metabolism were the dominant metabolic pathways in radicles.In contrast,the tricarboxylic acid cycle showed higher activity in DDS radicles compared to hypocotyl-cotyledons.We further demonstrated that carbohydratemetabolic pathways continue to play a dominant role in both dormancy maintenance and germination processes of P.koraiensis seeds.Notably,the carbohydratemetabolism in radicles likely exerts more critical regulatory functions in these two physiological processes compared to that in cotyledon and hypocotyl tissues.展开更多
Salt stress is a major threat to crop agricultural productivity.Salinity affects plants’physiological and biochemical functions by hampering metabolic functions and decreasing photosynthetic rates.Salinity causes hyp...Salt stress is a major threat to crop agricultural productivity.Salinity affects plants’physiological and biochemical functions by hampering metabolic functions and decreasing photosynthetic rates.Salinity causes hyperosmotic and hyperionic stress,directly impairing plant growth.In this study,eggplant seeds primed with moringa leaf extract(5%,10%,and 15%),nano-titaniumdioxide(0.02%,0.04%,and 0.06%),and ascorbic acid(0.5,1,and 2 mM)at different NaCl salt(0,75,and 150 mM)concentration were grown.The germination attributes(final germination percentage,germination index,mean germination time,and mean germination rate)and growth(root length,shoot length,fresh biomass,and dry biomass)were enhanced in the primed seedlings by the different priming agents,more prominently in ascorbic acid primed seedlings.The accumulation of hydrogen peroxide was greater in seedlings with higher salt levels.Similarly,the activity of antioxidant enzymes(superoxide dismutase,peroxidase,and catalase)was higher in primed seedlings compared to the control.At 150 mM,the antioxidant capacity was higher than 75 mM,and the seedlings’sodiumand chloride content was higher.The results demonstrate that seedling germination,growth,and activity of the antioxidant enzymes in ascorbic acid-primed seedlings increase their tolerance to salinity.Therefore,using different ascorbic acid concentrations(0.5,1,and 2 mM)as a priming agent to enhance germination and growth in saline conditions has proven effective.展开更多
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
In grape breeding programs,the extensive planting of seedlings is a crucial aspect.However,grape seeds display distinct dormancy traits,necessitating a prolonged cold stratification process for dormancy release.In ord...In grape breeding programs,the extensive planting of seedlings is a crucial aspect.However,grape seeds display distinct dormancy traits,necessitating a prolonged cold stratification process for dormancy release.In order to enhance the efficiency of breeding programs,this study presents an innovative in vitro embryo germination technique that eliminates the requirement for cold stratification of seeds.The method involves the disruption of peripheral tissue in grape seed embryos using a straightforward mechanical technique,resulting in the efficient production of a substantial quantity of seed embryos,with a germination rate of up to 88% for these isolated embryos.These embryos are subsequently cultured in vitro to facilitate germination into seedlings,thereby eliminating the need for cold stratification.Consequently,grape seedlings can be obtained within a significantly reduced timeframe of 30-38 d,expediting the overall grape breeding process.This novel approach not only accelerates grape hybridization but also streamlines the selection of new grape varieties,contributing to an efficient and time-sensitive breeding methodology.展开更多
The application of fungicides is an effective strategy for controlling plant diseases.Among these agents,plant-derived antifungal metabolites are particularly promising due to their eco-friendly and sustainable nature...The application of fungicides is an effective strategy for controlling plant diseases.Among these agents,plant-derived antifungal metabolites are particularly promising due to their eco-friendly and sustainable nature.Plant secondary metabolites typically exhibit broad-spectrum antifungal activity without selective toxicity against pathogens.However,only a small fraction of antifungal metabolites have been identified from the tens of thousands of known plant secondary metabolites.In this study,we conducted a metabolomic analysis on both blast-resistant(Digu)and-susceptible(Lijiangxintuanheigu)rice varieties to uncover novel metabolites that enhance blast resistance.We found that 24 and 48 h post-inoculation with Magnaporthe oryzae were critical time points for metabolomic profiling,based on the infected status of M.oryzae in rice and the observed differences in shikimate accumulation between the two varieties.Following metabolomic analysis,we identified nine flavonoids that were differentially accumulated and are considered potential candidates for disease control.Among these,apigenin-7-glucoside,rhamnetin,and spireoside were found to be effective in controlling blast disease,with spireoside demonstrating the most pronounced efficacy.We discovered that spireoside controlled blast disease by inhibiting both spore germination and appressorium formation in M.oryzae,primarily through disrupting cell membrane integrity.However,spireoside did not induce rice immunity.Furthermore,spireoside was also effective in controlling sheath blight disease.Thus,spireoside shows considerable promise as a candidate for the development of a fungicide for controlling plant diseases.展开更多
Low-temperature(LT)stress is a significant abiotic stress in rice growth,especially under direct seeding cultivation,where low temperatures can significantly affect seed germination and seedling growth of direct-seede...Low-temperature(LT)stress is a significant abiotic stress in rice growth,especially under direct seeding cultivation,where low temperatures can significantly affect seed germination and seedling growth of direct-seeded rice,thereby impacting the final yield of rice.In this study,we have identified a trehalose synthesis pathway gene,trehalose-6-phosphate phosphatase 3(Os TPP3),involved in the regulation of low-temperature(LT)germination in rice,as well as its upstream regulatory factor,the ABA signaling pathway gene OsbZIP23.LT stress induced the accumulation of ABA by upregulating the expression of Os NCED3.Consistently,the overexpression of Os NCED3 significantly inhibited seed germination under LT.RT-q PCR experiments found that the expression of OsbZIP23 was also significantly induced under LT stress and ABA treatment.Overexpression of OsbZIP23 has increased the sensitivity to LT stress of rice seed,resembling the phenotype of Os NCED3 overexpressing seeds.Furthermore,both LT stress and exogenous ABA treatment increased the trehalose content in WT seeds by upregulating the expression of Os TPP3.Enhancing the expression of Os TPP3 or application of exogenous trehalose have significantly increased the sensitivity to LT stress during seed germination.Transcriptional activation and yeast one-hybrid assays demonstrated that OsbZIP23 bound to the promoter of Os TPP3 and activated its expression,which was intensified by LT stress or the application of ABA.Our study discovered an ABAdependent OsbZIP23–Os TPP3 module that responds to LT stress,inhibiting seed germination under LT conditions by increasing trehalose accumulation,thus might balance the growth and stress resistance and provide a new insight into the genetic improvement of rice cultivars with better LT germination performance.展开更多
Porcine epidemic diarrhea virus(PEDV),an enteric coronavirus,is widely spread worldwide and causes huge economic losses.The effective measure to control the viral infection is to develop ideal vaccines.Here,the collag...Porcine epidemic diarrhea virus(PEDV),an enteric coronavirus,is widely spread worldwide and causes huge economic losses.The effective measure to control the viral infection is to develop ideal vaccines.Here,the collagenase equivalent domain(COE)of PEDV was displayed on the surface of nanoparticles(NPs)in order to develop a newer,safer and more effective subunit vaccine against PEDV.The monomeric COE was displayed on the mi3 protein,which self-assembles into nanoparticles composed of 60 subunits,using the SpyTag/SpyCatcher system.The size,zeta potential,microstructure of the COE-mi3 virus-like particles(VLPs)were investigated.The COE-mi3 VLPs that possessed good security,stability and better retention can be more efficiently taken up by antigen-presenting cells(APCs)and help promote dendritic cells(DCs)maturation.Moreover,COE-mi3 VLPs could prominently improve specifc antibody levels including neutralizing antibodies(NAbs),and serum IgG,mucosal IgA.Moreover,COE-mi3 VLPs elicited more activation of CD4^(+)and CD8^(+)T cells and production of IFN-γand IL-4 cytokines.In particular,COE-mi3 VLPs is an effectual antigen-delivery platform to enhance germinal center(GC)B cell responses.This structure-based self-assembly of NP gives great potential to be developed as a new subunit vaccines attractive platform,and may also provide new ideas for the development of other enteric coronavirus vaccines.展开更多
Rice seed germination marks the start of cultivation and influences subsequent seedling growth,and is affected by hormones and environmental factors.Ubiquitination plays a critical role in this process by regulating h...Rice seed germination marks the start of cultivation and influences subsequent seedling growth,and is affected by hormones and environmental factors.Ubiquitination plays a critical role in this process by regulating hormonal homeostasis.In the ubiquitination cascade,ubiquitin-conjugating enzymes(UBCs)function as ubiquitin carriers to determine linkage specificity of ubiquitin chains.In rice(Oryza sativa),39 UBC genes are identified,but only one gene OsUBC12 has been functionally studied to promote seed germination under low-temperatures in japonica rice.To elucidate the role of UBCs in seed germination,we generated CRISPR-Cas9 mutants for 23 UBC genes and overexpressed 20 members in rice.Among them,seven UBC genes(OsUBC4/6/7/12/25/27/48)were found to regulate seed germination,with OsUBC27 and OsUBC48 acting through the ABA pathway.Exogenous ABA inhibitors restored the germination rate of osubc27^(CR).RT-qPCR analysis revealed that the ABA synthesis genes OsNCED1-5 were significantly upregulated in the mutants.Further differential ubiquitination proteomics in knockout mutants and wild-type plants showed that OsUBC27 regulates ABA homeostasis by modulating ubiquitination of the ABA-degrading protein OsABA8ox1,thereby balancing seed dormancy and germination.Sequence analysis identified distinct haplotypes of the seven OsUBCs that showed differential distribution between japonica and indica subspecies.Our study provides valuable molecular targets for developing rice varieties resistant to seed vivipary.展开更多
Consecutive stresses,such as initial submergence during germination followed by water deficit during the seedling stage,pose significant challenges to direct-seeded rice cultivation.By Linkage disequilibrium analysis,...Consecutive stresses,such as initial submergence during germination followed by water deficit during the seedling stage,pose significant challenges to direct-seeded rice cultivation.By Linkage disequilibrium analysis,Sub1 and Dro1(Δbp:10 Mb),as well as Sub1 and TPP7(Δbp:6 Mb)were identified to exhibit long-range linkage disequilibrium(LRLD).Meta-QTL analysis further revealed that Sub1 and TPP7 co-segregated for tolerance to submergence at the germination and seedling stages.Based on this,we hypothesized that LRLD might influence plant responses to consecutive stresses.To test this hypothesis,we developed a structured recombinant inbred line population from a cross between Bhalum 2 and Nagina 22,with alleles(Sub1 and TPP7)in linkage equilibrium.Mendelian randomization analysis validated that the parental alleles,rather than the recombinant alleles of Sub1 and TPP7,significantly influenced 13 out of 41 traits under consecutive stress conditions.Additionally,16 minor additive effect QTLs were detected between the genomic regions,spanning Sub1 and TPP7 for various traits.A single allele difference between these genomic regions enhanced crown root number,root dry weight,and specific root area by 11.45%,15.69%,and 33.15%,respectively,under flooded germination conditions.Candidate gene analysis identified WAK79 and MRLK59 as regulators of stress responses during flooded germination,recovery,and subsequent water deficit conditions.These findings highlight the critical role of parental allele combinations and genomic regions between Sub1 and TPP7 in regulating the stress responses under consecutive stresses.Favourable haplotypes derived from these alleles can be utilized to improve stress resilience in direct-seeded rice.展开更多
Multiple phytohormones,including gibberellin(GA),abscisic acid(ABA),and indole-3-acetic acid(IAA),regulate seed germination.In this study,a barley aldehyde oxidase 1(HvAO1)gene was identified,which is located near the...Multiple phytohormones,including gibberellin(GA),abscisic acid(ABA),and indole-3-acetic acid(IAA),regulate seed germination.In this study,a barley aldehyde oxidase 1(HvAO1)gene was identified,which is located near the SD2(seed dormancy 2)region at the telomeric end of chromosome 5H.A doubledhaploid population(AC Metcalfe/Baudin)was used to characterize HvAO1 and validated its association with seed germination and malting quality.Aldehyde oxidase is predicted to catalyse the oxidation of various aldehydes,such as indoleacetaldehyde and abscisic aldehyde,into IAA and ABA,which is the final step of IAA/ABA biogenesis.This process influences the final IAA/ABA concentration in the seed,affecting the seed dormancy.Sequence analysis revealed substantial variations in the HvAO1 promoter regions between AC Metcalfe and Baudin.The combining seed germination tests,genetic variation analysis,gene expression,and phytohormone measurements showed that Baudin,which displays strong seed dormancy,has a specific sequence variation in the promoter region of the HvAO1 gene.This variation is associated with a higher expression level of the HvAO1 gene and an increased level of ABA than those in AC Metcalfe,which shows weak dormancy and lacks this sequence variation.In addition to its strong effect on the SD2 gene,HvAO1 shows excellent potential to fine-tune malting quality and seed dormancy,as evidenced by genotyping with HvAO1-specific markers,dormancy phenotypes,and malting quality.Our findings provide a new strategy for introducing favourable HvAO1 alleles to achieve the desired level of seed dormancy and high malting quality in barley.展开更多
文摘Seed viability of 18 576 accessions of 23 crops was monitored. After 10-12 years storage in National Crop Genebank ofChina (NCGC), more than 96.12% of the accessions maintained high germination percentage (>85%). The germination of95 accessions, accounting for 0.51% of the total, declined significantly from above 80% to below 70%. For each crop ofcarrot (Daucus carota var. sativa DC.), lettuce (Lactuca sativa L.), cotton (Gossypium sp. L.), flax (Linum usitatissimumL.) and castor-oil plant (Ricinus communis L.), the mean monitored germination percentage declined significantly as awhole, of which carrot and lettuce seeds lost viability more rapidly. Seed initial germination percentage and pre-storageenvironments affect subsequent seed viability in storage.
文摘This study aimed to observe the viability of the pollen grains of Malpighia emarginata DC. (West Indian cherry) and the action of a lectin in their germination. Lectins are proteins that specifically interact with carbohydrates, but don’t modify them and bind with high affinity and specificity, promoting a transfer of information that is clearly central to many cellular processes in living beings. For the viability test was used aniline blue in lactophenol. The in vitro germination test used was the hanging drop method, in control medium containing sucrose, boric acid, calcium nitrate and agar. The experiment dealt with three different treatments in order to pollen germination: growing medium without addition of lectin, with 1.0 μg/ml and with 3.0 μg/ml CPL lectin. This lectin is extracted from seeds of Crotalaria pallida L.-Leguminosae. Data on pollen grains were analyzed by one-way ANOVA, with 95% reliability and comparison of averages by Turkey test at 5% probability. It was found that despite previous high viability of the pollen grains (c. 70%), a germinability rate has been low, yet exceptionally larger in pollen samples placed on a growing medium with addition of 3.0 μg/ml of CPL lectin (24%). There was no significant difference among the pollen grains germinate in medium without lectin and those in medium with the addition of only 1.0 μg/ml. According to data obtained in the treatments, CPL lectin, with concentration of 3.0 μg/ml, influenced the formation of the pollen tube and thus more pollen germinated in Malpighia emarginata.
文摘Ex situ conservation in seed banks is a potential complementary conservation strategy for native plant species.It is well established that ex situ seed banking of native wild plants prolongs seed viability and thereby preserves genetic and species diversity for future use.We evaluated ex situ storage potential of eight halophytic species from deserts in the United Arab Emirates(UAE)by studying seed germination.Specifically,we examined the germinability of freshly collected seeds and seeds stored for three years in a seed bank.We also examined the effect of light conditions on fresh and stored seed germination.Fresh seeds of seven of the eight species tested had a higher germination rates under 12/12 h light/dark fluctuations than did those exposed to total darkness.Storage reduced light sensitivity in Halocnemum strobilaceum,Suaeda aegyptiaca,Salsola drummondii and Salsola imbricata,but increased the requirement for light in Arthrocnemum macrostachyum.In Anabasis setifera,storage decreased germination percentage when there was a 12-hour light/dark fluctuation,but increased germination rate when exposed to the dark treatment.Storage significantly reduced germination in both the light/dark and dark treatments in Suaeda vermiculata and S.aegyptiaca.Germination speed also responded differently to storage;whereas Timson's index significantly increased in A.macrostachyum and H.strobilaceum,it significantly decreased for S.drummondii,S.aegyptiaca and S.vermiculata.Germination of these species at a range of temperatures requires further testing;additionally,we strongly suggest that these laboratory findings be complemented by field studies.
基金funded by the Natural Science Foundation of Shandong Province(ZR2020MC144)the Scientific Research Training Program for Undergraduates of Qufu Normal University(XJ2024016).
文摘Strontium has similar chemical properties to calcium and has recently been recognized as a non-essential beneficial element for plants.In order to compare the effects of strontium and calcium on improving salt tolerance of Chinese cabbage during the germination stage,2,4,and 8 mmol/L of SrCl_(2),CaCl_(2) or an equimolar mixture of both were added separately to a 150 mmol/L NaCl solution.The results showed that Ca-Sr addition significantly increased seed viability,seed vigor,seed germination rate and seed germination uniformity of Chinese cabbage compared with the salt-control group.The differences in germination percentage(GP)and germination energy(GE)among the Ca-addition and Sr-addition groups were not significant,and the differences in coefficient of rate of germination(CRG),index of rate of germination(IRG)and coefficient of variation of the germination time(CVT)were relatively small,but clear differences were observed in germination index(GI),vigor index(VI)and coefficient of uniformity of germination(CUG).The results of GI and VI indicated that the higher the concentration of Ca-addition or Sr-addition,the more significant the enhancement of seed vigor.Under saline stress(150 mmol/L NaCl),the Ca-Sr co-addition outperformed Sr-treatment alone,and Ca-addition achieved the highest seed vigor at equivalent concentrations.Furthermore,all Ca-Sr treatments significantly enhanced the uniformity of Chinese cabbage sprouts exposed to 150 mM NaCl,with the best uniformity improved by the addition of 2 and 4 mmol/L SrCl_(2).Ca-Sr treatments increased the salt tolerance of Chinese cabbage sprouts during the germination stage mainly because the Ca2+and Sr2+significantly enhanced plasma membrane stability and reduced oxidative stress(as indicated by decreased contents of malondialdehyde and O2⋅-contents)in sprouts.The decrease of soluble sugar and proline content caused by Ca-Sr addition implies that elevated levels of these osmolytes were not the primary contributors to improved seed germinability in Chinese cabbage.These findings demonstrate that Sr is a beneficial element for enhancing salt tolerance in plants,laying a theoretical foundation for the development and application of strontium in agriculture.
基金This work was supported by the National Natural Science Foundation of China (Grant No. 39970471) and the Natural Science Foundation of Zhejiang Province (Grant No. 300220).
文摘A double haploid population, derived from anther culture of F, hybrid between a typical indica and a japonica (ZYQ8/JX17), has been used to investigate the low temperature germinability (LTG) at 15℃. The low temperature germinability of two parents was significantly different. In 6-11 d, the germination percentage of ZYQ8 was higher than that of JX17. In 12-16 d, the germination percentage of JX17 was higher than that of ZYQ8. The quantitative trait loci (QTLs) of every day for low temperature germinabilityhave been mapped based on a molecular linkage map constructed from this population. In 8-11 d, qLTG-9 was identified in C397B-RZ617B on chromosome 9, the additive effect was positive, showing that, the allele from JX17 could increase low temperature germinability. In 12-16 d, qLTG-4 was mapped between RG908 and CT563 on chromosome 4, the additive effect was negative, showing that the allele from ZYQ8 could increase low temperature germinability. These two QTLs were detected at different stages,
基金the Genetics and Agricultural Biotechnology Institute of Tabarestan (GABIT) Sari Agricultural Sciences and Natural Resources University (SANRU) for the use of the services and financial supports of this research
文摘The oilseed crop Camelina sativa exhibits salinity tolerance,but the effects on early growth stages across a range of different salts and in combination with salicylic acid(SA)have not been thoroughly evaluated.In this study,seeds were germinated in varying concentrations of six salts(NaCl,CaCl_(2),ZnCl_(2),KCl,MgSO_(4),and Na2SO_(4))with or without 0.5 mM SA.Using the halotime model,we estimated salt thresholds for germination and parameters of seedling growth.Germination and seedling growth parameters of camelina significantly decreased with increasing salt concentration across all salt types.Salts containing Zn and SO_(4) were most detrimental to germination and seedling growth.Except for KCl,0.5 mM SA generally reduced the salinity tolerance threshold(Saltb(50))of camelina.Specifically,Saltb(50)was 21.5%higher for KCl and 16.1%,25.0%,54.9%,21.0%,and 5.6%lower for CaCl_(2),NaCl,MgSO_(4),Na2SO_(4),and ZnCl_(2),respectively,when 0.5 mM SA was compared to 0 mM SA.Furthermore,camelina seedling growth was consistently more sensitive than germination across all salt types.SA did not significantly enhance germination or seedling growth and was harmful when combined with certain salts or at the germination stage.It can be concluded that both the type of salt and the concentration of SA are as critical as the salt concentration in saline irrigation water.
基金Supported by National Wheat Industry Technology System"Linyi Integrated Experimental Station"(CARS-03-66)Shandong Provincial Modern Agricultural Industry Technology System"Linyi Integrated Experimental Station"(SDATT-01-18).
文摘[Objectives]To identify the drought resistance of main wheat varieties in Shandong Province and screen suitable cultivars for dryland cultivation.[Methods]Employing eight varieties including Jimai 60 as test materials,this study simulated drought stress using 20%PEG-6000 and measured changes in germination-stage indicators.A comprehensive evaluation was conducted using the membership function method,incorporating relative coleoptile length,relative germ length,relative radicle length,relative germination rate,relative germination potential,and stress germination index.[Results]Drought stress not only reduced wheat seed germination rate but also inhibited the growth of the germ,coleoptile,and radicle.The D values of the eight varieties were ranked as follows:Jimai 60>Linmai 9>Yannong 999>Shannong 30>Shannong 28>Luyuan 502>Yannong 1212>Jimai 22.Based on D values,the eight dominant wheat varieties were classified into three categories:highly drought-resistant varieties(Linmai 9 and Jimai 60),moderately drought-resistant varieties(Yannong 999 and Shannong 30),and sensitive varieties(the others).Linmai 9 and Jimai 60 are recommended as suitable wheat varieties for dryland cultivation in Shandong Province.[Conclusions]Drought stress induced by 20%PEG-6000 reduced germination rate,germination potential,and germination index of wheat varieties while inhibiting the growth of coleoptiles and radicles.These indicators can provide a preliminary assessment of drought resistance in wheat cultivars.However,since filter paper was selected as the growth medium,root length measurement errors were introduced during root washing,leading to variations in final experimental results.Futuer studies could attempt using sterilized sand as an alternative growth medium.
文摘The present study examines the toxicological effects and bioaccumulation of strontium(Sr^(2+))in two Moroccan wheat species,Triticum durum(Nachit)and Triticum aestivum(Ibtissam).Germination rates and seedling growth parameters were evaluated under Sr^(2+)concentrations of 0,10,100,and 1000 mM.Results revealed a significant decline in germination rates as Sr^(2+)concentrations increased,with T.aestivum showing higher sensitivity compared to T.durum.Low Sr^(2+)concentrations(10 mM)initially promoted stem growth in T.aestivum,but growth declined sharply at higher concentrations.Both species sustained growth at moderate Sr^(2+)concentrations(100 mM),but experienced a substantial reduction at 1000 mM,with T.durum demonstrating slightly better tolerance.Elevated Sr^(2+)concentrations notably affected root length and stem branching,indicating severe phytotoxic effects.Enzyme activity assays showed that at low Sr^(2+)concentration(10 mM),GST,CAT,POD,and SOD activities were similar to the control.At moderate concentrations(100 mM),GST and POD activities increased,suggesting enhanced detoxification.At high concentrations(1000 mM),all enzyme activities were significantly elevated,reflecting a robust antioxidative defense mechanism.This study provides valuable insights into the toxicological impacts and physiological responses of these wheat species to Sr^(2+)stress.
基金supported by Shaanxi Province Qin Chuangyuan“Scientist+Engineer”team construction project(2024QCY-KXJ-079)Shaanxi Science and Technology Innovation Team Project(2024RSCXTD-70)for the financial support。
文摘Roasting is important for improving the content of bioactive compounds and enhancing the flavor of flaxseed oil.However,the effect of roasting time on germinated flaxseed oil(GFO)is unclear.Herein,the influence of roasting time(0–50 min)at a specific temperature of 160?C on the physicochemical properties,bioactive compounds,antioxidant capacity,and volatile compounds of GFO from three flaxseed varieties was examined.An extension in roasting time increased the a^(*)value of GFO,while the L^(*)and b^(*)values of GFO decreased.Higher chlorophylls(1.63±0.01–2.18±0.01 mg/kg),carotenoids(2.25±0.00–2.69±0.02 mg/kg),total phenolic content(156.75±2.93–200.03±6.29 mg GAE/kg),phytosterol(1801.93±30.64–1965.23±13.71 mg GAE/kg)and DPPH(320.11±18.22–432.19±14.95μmol TE/kg)and ABTS radical scavenging activity(810.68±16.29–1119.01±14.25μmol TE/kg)were detected in GFO after roasting for 20–30 min.However,the total tocopherol and unsaturated fatty acid content declined,and the composition of fatty acids changed insignificantly(P>0.05).GC–MS recognized 68 volatile compounds in GFO,in which pyrazine imparted a nutty flavor to the GFO.This study provides important information for the development of high-quality GFO.
基金supported by the National Natural Science Foundation of China(31901300).
文摘Pinus koraiensis is the dominant and constructive species of the zonal vegetation in Northeast China,known as the mixed broadleaf-Korean pine forest.Although carbohydrate metabolism pathways in the seed embryo are known to play crucial roles during seed dormancy and germination in P.koraiensis,it remains unclear whether these metabolic pathways function differentially across tissues.P.koraiensis seeds that had undergone different durations of moist chilling in their natural environment,yielding seeds with relatively deeper primary physiological dormancy(DDS)and seeds with released primary physiological dormancy(RDS).A non-targeted metabolomic analysis was conducted on the radicle and hypocotyl-cotyledon portions of both DDS and RDS,before and after a two-week incubation under favorable conditions.Under germination conditions,RDS and DDS showed divergent metabolic profiles,especially regarding carbohydrate metabolism.Specifically,RDS seeds showed significantly reduced substrates of respiratory metabolic pathways in both radicles and hypocotyl-cotyledons.Conversely,the intermediates of the carbohydrate metabolism pathway(particularly the tricarboxylic acid cycle)accumulating in radicles of DDS seeds under germination conditions.Moreover,in RDS,the carbohydrate metabolic pathways were more prevalent in the hypocotyl-cotyledon,while lysine degradation and ascorbate and aldarate metabolism were the dominant metabolic pathways in radicles.In contrast,the tricarboxylic acid cycle showed higher activity in DDS radicles compared to hypocotyl-cotyledons.We further demonstrated that carbohydratemetabolic pathways continue to play a dominant role in both dormancy maintenance and germination processes of P.koraiensis seeds.Notably,the carbohydratemetabolism in radicles likely exerts more critical regulatory functions in these two physiological processes compared to that in cotyledon and hypocotyl tissues.
文摘Salt stress is a major threat to crop agricultural productivity.Salinity affects plants’physiological and biochemical functions by hampering metabolic functions and decreasing photosynthetic rates.Salinity causes hyperosmotic and hyperionic stress,directly impairing plant growth.In this study,eggplant seeds primed with moringa leaf extract(5%,10%,and 15%),nano-titaniumdioxide(0.02%,0.04%,and 0.06%),and ascorbic acid(0.5,1,and 2 mM)at different NaCl salt(0,75,and 150 mM)concentration were grown.The germination attributes(final germination percentage,germination index,mean germination time,and mean germination rate)and growth(root length,shoot length,fresh biomass,and dry biomass)were enhanced in the primed seedlings by the different priming agents,more prominently in ascorbic acid primed seedlings.The accumulation of hydrogen peroxide was greater in seedlings with higher salt levels.Similarly,the activity of antioxidant enzymes(superoxide dismutase,peroxidase,and catalase)was higher in primed seedlings compared to the control.At 150 mM,the antioxidant capacity was higher than 75 mM,and the seedlings’sodiumand chloride content was higher.The results demonstrate that seedling germination,growth,and activity of the antioxidant enzymes in ascorbic acid-primed seedlings increase their tolerance to salinity.Therefore,using different ascorbic acid concentrations(0.5,1,and 2 mM)as a priming agent to enhance germination and growth in saline conditions has proven effective.
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 Natural Science Foundation of Beijing Academy of Agriculture and Forestry Sciences(Grant No.QNJJ202301)the Youth Research Foundation of Institute of Forestry and Pomology+2 种基金Beijing Academy of Agriculture and Forestry Science(Grant No.LGJJ202202)the BAAFS Funding for the Development of Distinguished Scientist(Grant No.JKZX202402)the Beijing Natural Science Foundation(Grant No.6242019)。
文摘In grape breeding programs,the extensive planting of seedlings is a crucial aspect.However,grape seeds display distinct dormancy traits,necessitating a prolonged cold stratification process for dormancy release.In order to enhance the efficiency of breeding programs,this study presents an innovative in vitro embryo germination technique that eliminates the requirement for cold stratification of seeds.The method involves the disruption of peripheral tissue in grape seed embryos using a straightforward mechanical technique,resulting in the efficient production of a substantial quantity of seed embryos,with a germination rate of up to 88% for these isolated embryos.These embryos are subsequently cultured in vitro to facilitate germination into seedlings,thereby eliminating the need for cold stratification.Consequently,grape seedlings can be obtained within a significantly reduced timeframe of 30-38 d,expediting the overall grape breeding process.This novel approach not only accelerates grape hybridization but also streamlines the selection of new grape varieties,contributing to an efficient and time-sensitive breeding methodology.
基金supported by the National Natural Science Foundation of China(Grant Nos.32172419,32372555,32121003,32425005,32072407,and 32272033)the National Key Research and Development Program of China(Grant No.2021YFA1300702)the Sichuan Science and Technology Program,China(Grant Nos.2023NSFSC0005,2023NSFSC1996,2024NSFSC0322,2024YFNH0014,2022NSFSC1755,2022-NSFSC1650,2022NSFSC0156,and 2022NSFSC0166).
文摘The application of fungicides is an effective strategy for controlling plant diseases.Among these agents,plant-derived antifungal metabolites are particularly promising due to their eco-friendly and sustainable nature.Plant secondary metabolites typically exhibit broad-spectrum antifungal activity without selective toxicity against pathogens.However,only a small fraction of antifungal metabolites have been identified from the tens of thousands of known plant secondary metabolites.In this study,we conducted a metabolomic analysis on both blast-resistant(Digu)and-susceptible(Lijiangxintuanheigu)rice varieties to uncover novel metabolites that enhance blast resistance.We found that 24 and 48 h post-inoculation with Magnaporthe oryzae were critical time points for metabolomic profiling,based on the infected status of M.oryzae in rice and the observed differences in shikimate accumulation between the two varieties.Following metabolomic analysis,we identified nine flavonoids that were differentially accumulated and are considered potential candidates for disease control.Among these,apigenin-7-glucoside,rhamnetin,and spireoside were found to be effective in controlling blast disease,with spireoside demonstrating the most pronounced efficacy.We discovered that spireoside controlled blast disease by inhibiting both spore germination and appressorium formation in M.oryzae,primarily through disrupting cell membrane integrity.However,spireoside did not induce rice immunity.Furthermore,spireoside was also effective in controlling sheath blight disease.Thus,spireoside shows considerable promise as a candidate for the development of a fungicide for controlling plant diseases.
基金funded by the Science and Technology Innovation Program of Hunan Province(2023NK1010,2024NK1010,2023NK2002)National Natural Science Foundation of China(U21A20208,32171927)+3 种基金Natural Science Foundation of Hunan Province(2025JJ30010,2023JJ40318)Guangdong Basic and Applied Basic Research Foundation(2022A1515111230)Shenzhen Science and Technology Program(JCYJ20220531103803008)the Hong Kong Research Grant Council(Ao E/M-05/12,Ao E/M-403/16,GRF12102423,12101722,12105824)。
文摘Low-temperature(LT)stress is a significant abiotic stress in rice growth,especially under direct seeding cultivation,where low temperatures can significantly affect seed germination and seedling growth of direct-seeded rice,thereby impacting the final yield of rice.In this study,we have identified a trehalose synthesis pathway gene,trehalose-6-phosphate phosphatase 3(Os TPP3),involved in the regulation of low-temperature(LT)germination in rice,as well as its upstream regulatory factor,the ABA signaling pathway gene OsbZIP23.LT stress induced the accumulation of ABA by upregulating the expression of Os NCED3.Consistently,the overexpression of Os NCED3 significantly inhibited seed germination under LT.RT-q PCR experiments found that the expression of OsbZIP23 was also significantly induced under LT stress and ABA treatment.Overexpression of OsbZIP23 has increased the sensitivity to LT stress of rice seed,resembling the phenotype of Os NCED3 overexpressing seeds.Furthermore,both LT stress and exogenous ABA treatment increased the trehalose content in WT seeds by upregulating the expression of Os TPP3.Enhancing the expression of Os TPP3 or application of exogenous trehalose have significantly increased the sensitivity to LT stress during seed germination.Transcriptional activation and yeast one-hybrid assays demonstrated that OsbZIP23 bound to the promoter of Os TPP3 and activated its expression,which was intensified by LT stress or the application of ABA.Our study discovered an ABAdependent OsbZIP23–Os TPP3 module that responds to LT stress,inhibiting seed germination under LT conditions by increasing trehalose accumulation,thus might balance the growth and stress resistance and provide a new insight into the genetic improvement of rice cultivars with better LT germination performance.
基金supported by the Major Scientific and Technological Project of the Henan Province,China(221100110600)the Beijing Life Science Academy,China(2024500CA0010)+1 种基金the Major Program of National Natural Science Foundation of China(32192452)the Chinese Postdoctoral Science Foundation(2023M743209)。
文摘Porcine epidemic diarrhea virus(PEDV),an enteric coronavirus,is widely spread worldwide and causes huge economic losses.The effective measure to control the viral infection is to develop ideal vaccines.Here,the collagenase equivalent domain(COE)of PEDV was displayed on the surface of nanoparticles(NPs)in order to develop a newer,safer and more effective subunit vaccine against PEDV.The monomeric COE was displayed on the mi3 protein,which self-assembles into nanoparticles composed of 60 subunits,using the SpyTag/SpyCatcher system.The size,zeta potential,microstructure of the COE-mi3 virus-like particles(VLPs)were investigated.The COE-mi3 VLPs that possessed good security,stability and better retention can be more efficiently taken up by antigen-presenting cells(APCs)and help promote dendritic cells(DCs)maturation.Moreover,COE-mi3 VLPs could prominently improve specifc antibody levels including neutralizing antibodies(NAbs),and serum IgG,mucosal IgA.Moreover,COE-mi3 VLPs elicited more activation of CD4^(+)and CD8^(+)T cells and production of IFN-γand IL-4 cytokines.In particular,COE-mi3 VLPs is an effectual antigen-delivery platform to enhance germinal center(GC)B cell responses.This structure-based self-assembly of NP gives great potential to be developed as a new subunit vaccines attractive platform,and may also provide new ideas for the development of other enteric coronavirus vaccines.
基金supported by the Zhejiang Provincial Natural Science Foundation,China(ZCLMS25C1302)the Central Public-interest Scientific Institution Basal Research Fund(CPSIBRF-CNRRI-202408)the Agricultural Science and Technology Innovation Program(ASTIP)
文摘Rice seed germination marks the start of cultivation and influences subsequent seedling growth,and is affected by hormones and environmental factors.Ubiquitination plays a critical role in this process by regulating hormonal homeostasis.In the ubiquitination cascade,ubiquitin-conjugating enzymes(UBCs)function as ubiquitin carriers to determine linkage specificity of ubiquitin chains.In rice(Oryza sativa),39 UBC genes are identified,but only one gene OsUBC12 has been functionally studied to promote seed germination under low-temperatures in japonica rice.To elucidate the role of UBCs in seed germination,we generated CRISPR-Cas9 mutants for 23 UBC genes and overexpressed 20 members in rice.Among them,seven UBC genes(OsUBC4/6/7/12/25/27/48)were found to regulate seed germination,with OsUBC27 and OsUBC48 acting through the ABA pathway.Exogenous ABA inhibitors restored the germination rate of osubc27^(CR).RT-qPCR analysis revealed that the ABA synthesis genes OsNCED1-5 were significantly upregulated in the mutants.Further differential ubiquitination proteomics in knockout mutants and wild-type plants showed that OsUBC27 regulates ABA homeostasis by modulating ubiquitination of the ABA-degrading protein OsABA8ox1,thereby balancing seed dormancy and germination.Sequence analysis identified distinct haplotypes of the seven OsUBCs that showed differential distribution between japonica and indica subspecies.Our study provides valuable molecular targets for developing rice varieties resistant to seed vivipary.
基金supported by the Director General,Indian Council of Agricultural Research(ICAR),New Delhithe Director,ICAR-National Rice Research Institute,Cuttack.
文摘Consecutive stresses,such as initial submergence during germination followed by water deficit during the seedling stage,pose significant challenges to direct-seeded rice cultivation.By Linkage disequilibrium analysis,Sub1 and Dro1(Δbp:10 Mb),as well as Sub1 and TPP7(Δbp:6 Mb)were identified to exhibit long-range linkage disequilibrium(LRLD).Meta-QTL analysis further revealed that Sub1 and TPP7 co-segregated for tolerance to submergence at the germination and seedling stages.Based on this,we hypothesized that LRLD might influence plant responses to consecutive stresses.To test this hypothesis,we developed a structured recombinant inbred line population from a cross between Bhalum 2 and Nagina 22,with alleles(Sub1 and TPP7)in linkage equilibrium.Mendelian randomization analysis validated that the parental alleles,rather than the recombinant alleles of Sub1 and TPP7,significantly influenced 13 out of 41 traits under consecutive stress conditions.Additionally,16 minor additive effect QTLs were detected between the genomic regions,spanning Sub1 and TPP7 for various traits.A single allele difference between these genomic regions enhanced crown root number,root dry weight,and specific root area by 11.45%,15.69%,and 33.15%,respectively,under flooded germination conditions.Candidate gene analysis identified WAK79 and MRLK59 as regulators of stress responses during flooded germination,recovery,and subsequent water deficit conditions.These findings highlight the critical role of parental allele combinations and genomic regions between Sub1 and TPP7 in regulating the stress responses under consecutive stresses.Favourable haplotypes derived from these alleles can be utilized to improve stress resilience in direct-seeded rice.
基金supported by the Engineering Research Center of Ecology and Agricultural Use of Wetland,Ministry of Education(KFT202302)the National Natural Science Foundation of China(32372052).
文摘Multiple phytohormones,including gibberellin(GA),abscisic acid(ABA),and indole-3-acetic acid(IAA),regulate seed germination.In this study,a barley aldehyde oxidase 1(HvAO1)gene was identified,which is located near the SD2(seed dormancy 2)region at the telomeric end of chromosome 5H.A doubledhaploid population(AC Metcalfe/Baudin)was used to characterize HvAO1 and validated its association with seed germination and malting quality.Aldehyde oxidase is predicted to catalyse the oxidation of various aldehydes,such as indoleacetaldehyde and abscisic aldehyde,into IAA and ABA,which is the final step of IAA/ABA biogenesis.This process influences the final IAA/ABA concentration in the seed,affecting the seed dormancy.Sequence analysis revealed substantial variations in the HvAO1 promoter regions between AC Metcalfe and Baudin.The combining seed germination tests,genetic variation analysis,gene expression,and phytohormone measurements showed that Baudin,which displays strong seed dormancy,has a specific sequence variation in the promoter region of the HvAO1 gene.This variation is associated with a higher expression level of the HvAO1 gene and an increased level of ABA than those in AC Metcalfe,which shows weak dormancy and lacks this sequence variation.In addition to its strong effect on the SD2 gene,HvAO1 shows excellent potential to fine-tune malting quality and seed dormancy,as evidenced by genotyping with HvAO1-specific markers,dormancy phenotypes,and malting quality.Our findings provide a new strategy for introducing favourable HvAO1 alleles to achieve the desired level of seed dormancy and high malting quality in barley.
