Malic acid is a crucial determinant of apple(Malus domestica)fruit quality,influencing acidity and flavor.While transcriptional regulation of malic acid metabolism is well-studied,post-transcriptional control and the ...Malic acid is a crucial determinant of apple(Malus domestica)fruit quality,influencing acidity and flavor.While transcriptional regulation of malic acid metabolism is well-studied,post-transcriptional control and the role of jasmonate(JA)remain largely unexplored.We identify a novel regulatory pathway involving JA signaling,a micro RNA(mi RNA),and vacuolar transport regulators that control malic acid accumulation in apple fruit.We show that mdm-mi R858,which increases during fruit maturation,directly targets and cleaves Md MYB73 transcripts.Md MYB73 is a known positive regulator of vacuolar H+-pumping and malate transport,activating genes like Md VHA-A,Md VHP,and Md ALMT9.Overexpression of mdm-mi R858 suppressed Md MYB73,thereby reducing Md VHA-A,Md VHP,and Md ALMT9 expression and malic acid content in apple calli,fruits,and GL-3plantlets,while silencing mdm-mi R858 had opposite effects.Crucially,the JA-responsive transcription factor Md MYC2,the expression of which increases during fruit maturation,directly binds the mdm-mi R858 promoter and activates its expression.Furthermore,the Mediator complex subunit Md MED25 interacts with Md MYC2,enhancing this activation.Manipulating Md MYC2 or Md MED25expression altered mdm-mi R858 levels,Md MYB73expression,and malic acid accumulation,mirroring exogenous methyl jasmonate(Me JA)treatment effects.A mi R858-resistant Md MYB73 variant confirmed the miRNA-target interaction's specificity and functional significance.Our findings reveal a novel JA-Md MYC2/MdMED25-mi R858-Md MYB73regulatory cascade controlling malic acid accumulation in apple,providing a mechanistic link between hormonal signaling and post-transcriptional regulation of fruit acidity.This discovery offers new targets for manipulating fruit quality.展开更多
Verticillium wilt,caused by Verticillium dahliae,seriously restricts the yield and quality improvement of cotton.Previous studies have revealed the involvement of WRKY members in plant defense against V.dahliae,but th...Verticillium wilt,caused by Verticillium dahliae,seriously restricts the yield and quality improvement of cotton.Previous studies have revealed the involvement of WRKY members in plant defense against V.dahliae,but the underlying mechanisms involved need to be further elucidated.Here,we demonstrated that Gossypium hirsutum WRKY DNA-binding protein 33(GhWRKY33) functions as a negative regulator in plant defense against V.dahliae.GhWRKY33 expression is induced rapidly by V.dahliae and methyl jasmonate,and overexpression of GhWRKY33 reduces plant tolerance to V.dahliae in Arabidopsis.Quantitative RT-PCR analysis revealed that expression of several JA-associated genes was significantly repressed in GhWRKY33 overexpressing transgenic plants.Yeast one-hybrid analysis revealed that GhWRKY33 may repress the transcription of both AtERF1 and GhERF2 through its binding to their promoters.Protein-protein interaction analysis suggested that GhWRKY33 interacts with G.hirsutum JASMONATE ZIM-domain protein 3(GhJAZ3).Similarly,overexpression of GhJAZ3 also decreases plant tolerance to V.dahliae.Furthermore,GhJAZ3 acts synergistically with GhWRKY33 to suppress both AtERF1 and GhERF2 expression.Our results imply that GhWRKY33 may negatively regulate plant tolerance to V.dahliae via the JA-mediated signaling pathway.展开更多
Background Thidiazuron(TDZ)is a widely used chemical defoliant in commercial cotton production and is often combined with the herbicide Diuron to form the commercial defoliant mixture known as TDZ·Diuron(T·D...Background Thidiazuron(TDZ)is a widely used chemical defoliant in commercial cotton production and is often combined with the herbicide Diuron to form the commercial defoliant mixture known as TDZ·Diuron(T·D,540 g·L^(-1)suspension).However,due to increasing concerns about the environmental and biological risks posed by Diuron,there is an urgent need to develop safer and more effective alternatives.Jasmonic acid(JA)and its derivatives are key phytohormones in organ senescence and abscission.Results Greenhouse experiments at the seedling stage revealed that Me-JA(0.8 mmol·L^(-1))alone did not induce defoliation.However,its co-application with TDZ(0.45 mmol·L^(-1))at concentrations of 0.6,0.8,and 1.0 mmol·L^(-1)significantly enhanced defoliation efficacy.The most effective combination—TDZ with 0.8 mmol·L^(-1)Me-JA—achieved a 100%defoliation rate at 5 days after treatment(DAT),23.7 percentage points higher than TDZ alone,and comparable to the commercial TDZ·Diuron formulation with equivalent TDZ content.Field trials conducted in Beijing(Shangzhuang),Hebei(Hejian),and Xinjiang(Shihezi)confirmed that the combination of 0.6 mmol·L^(-1)Me-JA with 1.70 mmol·L^(-1)TDZ provided optimal defoliation performance.At 21 DAT,the defoliation rate increased by 13.5–16.3 percentage points compared with TDZ alone.Furthermore,boll opening rates improved by 5.7–12.7 percentage points relative to TDZ-only treatments.Phytohormonal analyses from the Shangzhuang site showed that the combined treatment significantly altered hormone levels in both leaves and petioles.Compared with TDZ alone,the mixture reduced concentrations of auxin(IAA),cytokinins(Z+ZR,iP+iPA,DHZ+DHZR),and gibberellic acid(GA3),while increasing levels of JA,abscisic acid(ABA),and brassinosteroids(BR).These hormonal shifts may underlie the enhanced defoliation observed with the combined treatment.Importantly,the TDZ-Me-JA combination did not adversely affect cotton yield,yield components,or fiber quality.Conclusion The combination of Me-JA and TDZ has a good defoliation effect without affecting crop yield or fiber quality.And it provides a promising foundation for the development of novel,environmentally friendly cotton defoliants.展开更多
Jasmonates(JAs)are essential phytohormones that coordinate plant defense and development in response to unpredictable environments.Recent advances have highlighted the SCF COI1-JAZ-MYC2-MED25 module as a central hub f...Jasmonates(JAs)are essential phytohormones that coordinate plant defense and development in response to unpredictable environments.Recent advances have highlighted the SCF COI1-JAZ-MYC2-MED25 module as a central hub for JA signaling,orchestrating transcriptional repression,derepression,activation,amplification,and feedback termination.This review summarizes current insights into the roles of JA in the regulation of biotic and abiotic stress responses and agronomic traits,including root development,regeneration,fertility,flowering,leaf senescence,and seed development,with a particular emphasis on the crosstalk between JA and a wound-induced peptide hormone,systemin,which mediates systemic wound responses.A deeper understanding of the JA regulatory mechanisms will provide valuable strategies for engineering crops with enhanced stress resilience and improved yields.We further propose JA-based strategies as a promising avenue for crop improvement.展开更多
As sessile organisms,plants must adapt various stresses.Accordingly,they have evolved several plant-specific growth and developmental processes.WRKY53 is a member of the WRKY transcription factor family,which plays a ...As sessile organisms,plants must adapt various stresses.Accordingly,they have evolved several plant-specific growth and developmental processes.WRKY53 is a member of the WRKY transcription factor family,which plays a crucial role in rice growth and development,stress response,and hormone signal transduction.This review discusses the role of WRKY53 in stress response,focusing on its functions in cold tolerance,salt tolerance,disease resistance,and pest defense,and explores its role in regulating rice leaf senescence and seed germination.This article also proposes future research directions,including functional genomics studies,protein interaction network analyses,hormone signal transduction pathways,genetic improvement strategies,applications of gene editing technologies,molecular basis of stress responses,cross-species functional conservation,and bioinformatics and comparative genomics research.This review highlights the importance of WRKY53 in rice biology and provides new perspectives and strategies for future research and genetic improvement of rice.展开更多
[Objective] This study was carried out to determine the induction effect of jasmonic acid（JA）on powdery mildew resistance in wheat,the activation effect on the expressions of plant disease resistance related genes,a...[Objective] This study was carried out to determine the induction effect of jasmonic acid（JA）on powdery mildew resistance in wheat,the activation effect on the expressions of plant disease resistance related genes,and to investigate the relationship between the induced resistance and the gene expression patterns.[Method] Three powdery mildew susceptible cultivars of ＂Chinese Spring＂,＂Pumai 9＂ and ＂Zhoumai 18＂ typically representing different phenotypes in the field were employed.The powdery mildew was assessed by detached leaf assay,and real time quantitative RT-PCR was used to determine the expression patterns of 9 disease resistance related genes of PR1（PR1.1）,PR2（β,1-3 glucanase）,PR3（chitinase）,PR4（wheatwin1）,PR5（thaumatin-like protein）,PR9（TaPERO,peroxidase）,PR10,TaGLP2a（germin-like）and Ta-JA2（jasmonate-induced protein）in leaf of the three cultivars.[Result] MeJA application enhanced the powdery mildew resistances of ＂Chinese Spring＂,＂Pumai 9＂ and ＂Zhoumai 18＂.The induced powdery mildew resistance could be detected from 12 h to 96 h after MeJA treatment,and the peak value was at 24 h.Though there were differences between the three cultivars,MeJA significantly effect on the expressions of the 8 disease resistance related genes except TaGLP2a,and the peak values were at 12 h,24 h or 48 h after treatments.The strongest activation of MeJA was on PR9 and PR1 that their expressions could reach more than 100 times of the untreated samples.MeJA strongly activated PR2、PR4、PR5、PR3、PR10 and Ta-JA2,their expression could reach 10 to 70 times,and there was almost no activation effect on TaGLP2a.The induced powdery mildew resistance positively correlated with the induced expressions of the 8 disease related genes.[Conclusion] The induced powdery mildew resistance positively correlated with the induced expressions of the disease related genes.Jasmonate signalling plays a role in defence against Blumeria graminis f.sp.tritici.and future manipulation of this pathway may improve powdery mildew resistance in wheat.展开更多
The contents of seven different phenolic acids such as gallic acid, catechinic acid, pyrocatechol, caffeic acid, coumaric acid, ferulic acid and benzoic acid in the poplar leaves （Populus Simonii×Populus Pyramib...The contents of seven different phenolic acids such as gallic acid, catechinic acid, pyrocatechol, caffeic acid, coumaric acid, ferulic acid and benzoic acid in the poplar leaves （Populus Simonii×Populus Pyramibalis c.v and Populus deltoids） suffocated by Methyl jasmonate （MeJA） and Methyl salicylate （MeSA） were monitored for analyzing their functions in interplant communications by using high-pressure liquid chromatography （HPLC）.The results showed that the contents of phenolic acids had obviously difference in leaves exposed to either MeSA or MeJA.When P.deltoides leaves exposed to MeJA or MeSA, the level of gallic acid, coumaric acid, caffeic acid, ferulic acid and benzoic acid was increased, gallic acid in leaves treated with MeJA comes to a peak at 24 h while to a peak at 12-d having leaves treated with MeSA.When P.Simonii ×P.Pyramibalis c.v leaves were exposed to MeJA or MeSA, the level of gallic acid, pyrocatechol and ferulic acid was increased; The catechinic acid and benzoic acid had a little drop; The caffeic acid and coumaric acid were undetected in both suffocated and control leaves.This changed pattern indicated that MeJA and MeSA can act as airborne signals to induce defense response of plants.展开更多
Methyl jasmonate （MeJA） is a plant-signaling molecule that regulates plant morphogenesis and expression of plant defense genes. To determine the role of the endogenous MeJA levels in the development of plants, trans...Methyl jasmonate （MeJA） is a plant-signaling molecule that regulates plant morphogenesis and expression of plant defense genes. To determine the role of the endogenous MeJA levels in the development of plants, transgenic soybean [Glycine max （L.） Merrill] plants harboring NTR1 gene encoding for jasmonic acid carboxyl methyltransferase （JMT） were produced. The activation of NTR1 gene expression resulted in the production of MeJA. Overexpression of the NTR1 cDNA under the regulation of cauliflower mosaic virus （CaMV） 35S promoter in the transgenic soybean plants was confirmed using Northern blot analysis. The significant differences in leaf and root growth patterns were observed between the transgenic plants and the wild-type plants. The leaves of the transgenic plants were slightly elongated in length but dramatically narrowed in width compared with the nontrans-formed wild-type plants. In addition, elongation of primary root was inhibited in the overexpressed transgenic soybean plantlets, whereas the development of lateral root was stimulated relative to the nontransformed plants. The leaves of the transgenic plants showed 2-2.5-fold higher levels of MeJA than the control plants. These results indicated that the increased endogenous levels of MeJA is involved in regulation of morphogenesis in soybean plants.展开更多
[Objective]The aim was to explore the molecular mechanism of plant resistance to various stress response.[Method]The expression of LeWRKY1 in tomato seedlings under treatment with B.cinerea,exogenous JA and SA were ex...[Objective]The aim was to explore the molecular mechanism of plant resistance to various stress response.[Method]The expression of LeWRKY1 in tomato seedlings under treatment with B.cinerea,exogenous JA and SA were explored by real time quantitative RT-PCR technology.[Result]JA induced the expression of LeWRKY1,but SA did not.LeWRKY1 expression was up-regulated under B.cinerea infection.[Conclusion]LeWRKY1 might be involved in the tomato defense response to B.cinerea through JA dependent but SA independent signal pathway.展开更多
Zhaohui peaches(Prunus persica Batsch)were treated with 0(CK), 1, 10 or 100 μmol L-1 methyl jasmonate(MeJA)vapor at 20℃ for 24 h before stored at 0℃ for 35 d. The untreated fruits showed chilling injury(CD symptoms...Zhaohui peaches(Prunus persica Batsch)were treated with 0(CK), 1, 10 or 100 μmol L-1 methyl jasmonate(MeJA)vapor at 20℃ for 24 h before stored at 0℃ for 35 d. The untreated fruits showed chilling injury(CD symptoms after 4 wk of storage, as indicated by increased fruit firmness and reduced ex-tractable juice, which is referred as leatheriness. Treatment with 1 and 10 μmol L-1 MeJA promoted normal ripening and softening, maintained higher levels of extractable juice, titratable acidity, pectinesterase(PE)and polygalacturonase(PC)activities, inhibited increases in fruit fresh weight loss, decay incidence, electrolyte leakage and MDA content, and improved color development, thereby preventing chilling injury symptoms development and maintaining edible quality. MeJA treatment also delayed the climacteric rise in respiratory rate, but promoted ethylene production during the later period of cold storage, suggesting that ethylene may involve in CI development of peaches. These results indicate that 1 and 10 μmol L-1 MeJA treatments could be used to reduce CI development and decay incidence in peaches.展开更多
基金supported by the Earmarked Fund for Modern Agro-industry Technology Research System,China(CARS27)the National Natural Science Foundation of China(32072555)+1 种基金the Nationally Funded Postdoctoral Researcher Program(GZC20230863)the China Postdoctoral Science Foundation(2024M760968)。
文摘Malic acid is a crucial determinant of apple(Malus domestica)fruit quality,influencing acidity and flavor.While transcriptional regulation of malic acid metabolism is well-studied,post-transcriptional control and the role of jasmonate(JA)remain largely unexplored.We identify a novel regulatory pathway involving JA signaling,a micro RNA(mi RNA),and vacuolar transport regulators that control malic acid accumulation in apple fruit.We show that mdm-mi R858,which increases during fruit maturation,directly targets and cleaves Md MYB73 transcripts.Md MYB73 is a known positive regulator of vacuolar H+-pumping and malate transport,activating genes like Md VHA-A,Md VHP,and Md ALMT9.Overexpression of mdm-mi R858 suppressed Md MYB73,thereby reducing Md VHA-A,Md VHP,and Md ALMT9 expression and malic acid content in apple calli,fruits,and GL-3plantlets,while silencing mdm-mi R858 had opposite effects.Crucially,the JA-responsive transcription factor Md MYC2,the expression of which increases during fruit maturation,directly binds the mdm-mi R858 promoter and activates its expression.Furthermore,the Mediator complex subunit Md MED25 interacts with Md MYC2,enhancing this activation.Manipulating Md MYC2 or Md MED25expression altered mdm-mi R858 levels,Md MYB73expression,and malic acid accumulation,mirroring exogenous methyl jasmonate(Me JA)treatment effects.A mi R858-resistant Md MYB73 variant confirmed the miRNA-target interaction's specificity and functional significance.Our findings reveal a novel JA-Md MYC2/MdMED25-mi R858-Md MYB73regulatory cascade controlling malic acid accumulation in apple,providing a mechanistic link between hormonal signaling and post-transcriptional regulation of fruit acidity.This discovery offers new targets for manipulating fruit quality.
基金This work was supported by the National key R&D plan(2016YFD0101006)Yunnan Fundamental Research Projects(2019FA010).
文摘Verticillium wilt,caused by Verticillium dahliae,seriously restricts the yield and quality improvement of cotton.Previous studies have revealed the involvement of WRKY members in plant defense against V.dahliae,but the underlying mechanisms involved need to be further elucidated.Here,we demonstrated that Gossypium hirsutum WRKY DNA-binding protein 33(GhWRKY33) functions as a negative regulator in plant defense against V.dahliae.GhWRKY33 expression is induced rapidly by V.dahliae and methyl jasmonate,and overexpression of GhWRKY33 reduces plant tolerance to V.dahliae in Arabidopsis.Quantitative RT-PCR analysis revealed that expression of several JA-associated genes was significantly repressed in GhWRKY33 overexpressing transgenic plants.Yeast one-hybrid analysis revealed that GhWRKY33 may repress the transcription of both AtERF1 and GhERF2 through its binding to their promoters.Protein-protein interaction analysis suggested that GhWRKY33 interacts with G.hirsutum JASMONATE ZIM-domain protein 3(GhJAZ3).Similarly,overexpression of GhJAZ3 also decreases plant tolerance to V.dahliae.Furthermore,GhJAZ3 acts synergistically with GhWRKY33 to suppress both AtERF1 and GhERF2 expression.Our results imply that GhWRKY33 may negatively regulate plant tolerance to V.dahliae via the JA-mediated signaling pathway.
基金funded by the China Agriculture Research System(CARS–15–16)。
文摘Background Thidiazuron(TDZ)is a widely used chemical defoliant in commercial cotton production and is often combined with the herbicide Diuron to form the commercial defoliant mixture known as TDZ·Diuron(T·D,540 g·L^(-1)suspension).However,due to increasing concerns about the environmental and biological risks posed by Diuron,there is an urgent need to develop safer and more effective alternatives.Jasmonic acid(JA)and its derivatives are key phytohormones in organ senescence and abscission.Results Greenhouse experiments at the seedling stage revealed that Me-JA(0.8 mmol·L^(-1))alone did not induce defoliation.However,its co-application with TDZ(0.45 mmol·L^(-1))at concentrations of 0.6,0.8,and 1.0 mmol·L^(-1)significantly enhanced defoliation efficacy.The most effective combination—TDZ with 0.8 mmol·L^(-1)Me-JA—achieved a 100%defoliation rate at 5 days after treatment(DAT),23.7 percentage points higher than TDZ alone,and comparable to the commercial TDZ·Diuron formulation with equivalent TDZ content.Field trials conducted in Beijing(Shangzhuang),Hebei(Hejian),and Xinjiang(Shihezi)confirmed that the combination of 0.6 mmol·L^(-1)Me-JA with 1.70 mmol·L^(-1)TDZ provided optimal defoliation performance.At 21 DAT,the defoliation rate increased by 13.5–16.3 percentage points compared with TDZ alone.Furthermore,boll opening rates improved by 5.7–12.7 percentage points relative to TDZ-only treatments.Phytohormonal analyses from the Shangzhuang site showed that the combined treatment significantly altered hormone levels in both leaves and petioles.Compared with TDZ alone,the mixture reduced concentrations of auxin(IAA),cytokinins(Z+ZR,iP+iPA,DHZ+DHZR),and gibberellic acid(GA3),while increasing levels of JA,abscisic acid(ABA),and brassinosteroids(BR).These hormonal shifts may underlie the enhanced defoliation observed with the combined treatment.Importantly,the TDZ-Me-JA combination did not adversely affect cotton yield,yield components,or fiber quality.Conclusion The combination of Me-JA and TDZ has a good defoliation effect without affecting crop yield or fiber quality.And it provides a promising foundation for the development of novel,environmentally friendly cotton defoliants.
基金supported by the National Natural Science Foundation of China(32370332 and 32202481)the Natural Science Foundation of Hainan Province(325RC839).
文摘Jasmonates(JAs)are essential phytohormones that coordinate plant defense and development in response to unpredictable environments.Recent advances have highlighted the SCF COI1-JAZ-MYC2-MED25 module as a central hub for JA signaling,orchestrating transcriptional repression,derepression,activation,amplification,and feedback termination.This review summarizes current insights into the roles of JA in the regulation of biotic and abiotic stress responses and agronomic traits,including root development,regeneration,fertility,flowering,leaf senescence,and seed development,with a particular emphasis on the crosstalk between JA and a wound-induced peptide hormone,systemin,which mediates systemic wound responses.A deeper understanding of the JA regulatory mechanisms will provide valuable strategies for engineering crops with enhanced stress resilience and improved yields.We further propose JA-based strategies as a promising avenue for crop improvement.
基金supported by the Hubei Provincial Natural Science Foundation,China(Grant No.2024AFB917).
文摘As sessile organisms,plants must adapt various stresses.Accordingly,they have evolved several plant-specific growth and developmental processes.WRKY53 is a member of the WRKY transcription factor family,which plays a crucial role in rice growth and development,stress response,and hormone signal transduction.This review discusses the role of WRKY53 in stress response,focusing on its functions in cold tolerance,salt tolerance,disease resistance,and pest defense,and explores its role in regulating rice leaf senescence and seed germination.This article also proposes future research directions,including functional genomics studies,protein interaction network analyses,hormone signal transduction pathways,genetic improvement strategies,applications of gene editing technologies,molecular basis of stress responses,cross-species functional conservation,and bioinformatics and comparative genomics research.This review highlights the importance of WRKY53 in rice biology and provides new perspectives and strategies for future research and genetic improvement of rice.
基金Supported by The Key Project of Science and Technology of HenanProvince(102102110040)Innovation Scientists and the Innovation Fund for Outstanding Scholars of Henan Province(104200510013)~~
文摘[Objective] This study was carried out to determine the induction effect of jasmonic acid（JA）on powdery mildew resistance in wheat,the activation effect on the expressions of plant disease resistance related genes,and to investigate the relationship between the induced resistance and the gene expression patterns.[Method] Three powdery mildew susceptible cultivars of ＂Chinese Spring＂,＂Pumai 9＂ and ＂Zhoumai 18＂ typically representing different phenotypes in the field were employed.The powdery mildew was assessed by detached leaf assay,and real time quantitative RT-PCR was used to determine the expression patterns of 9 disease resistance related genes of PR1（PR1.1）,PR2（β,1-3 glucanase）,PR3（chitinase）,PR4（wheatwin1）,PR5（thaumatin-like protein）,PR9（TaPERO,peroxidase）,PR10,TaGLP2a（germin-like）and Ta-JA2（jasmonate-induced protein）in leaf of the three cultivars.[Result] MeJA application enhanced the powdery mildew resistances of ＂Chinese Spring＂,＂Pumai 9＂ and ＂Zhoumai 18＂.The induced powdery mildew resistance could be detected from 12 h to 96 h after MeJA treatment,and the peak value was at 24 h.Though there were differences between the three cultivars,MeJA significantly effect on the expressions of the 8 disease resistance related genes except TaGLP2a,and the peak values were at 12 h,24 h or 48 h after treatments.The strongest activation of MeJA was on PR9 and PR1 that their expressions could reach more than 100 times of the untreated samples.MeJA strongly activated PR2、PR4、PR5、PR3、PR10 and Ta-JA2,their expression could reach 10 to 70 times,and there was almost no activation effect on TaGLP2a.The induced powdery mildew resistance positively correlated with the induced expressions of the 8 disease related genes.[Conclusion] The induced powdery mildew resistance positively correlated with the induced expressions of the disease related genes.Jasmonate signalling plays a role in defence against Blumeria graminis f.sp.tritici.and future manipulation of this pathway may improve powdery mildew resistance in wheat.
基金This research is supported by National Natural Science Foundation of China (No.30170764)
文摘The contents of seven different phenolic acids such as gallic acid, catechinic acid, pyrocatechol, caffeic acid, coumaric acid, ferulic acid and benzoic acid in the poplar leaves （Populus Simonii×Populus Pyramibalis c.v and Populus deltoids） suffocated by Methyl jasmonate （MeJA） and Methyl salicylate （MeSA） were monitored for analyzing their functions in interplant communications by using high-pressure liquid chromatography （HPLC）.The results showed that the contents of phenolic acids had obviously difference in leaves exposed to either MeSA or MeJA.When P.deltoides leaves exposed to MeJA or MeSA, the level of gallic acid, coumaric acid, caffeic acid, ferulic acid and benzoic acid was increased, gallic acid in leaves treated with MeJA comes to a peak at 24 h while to a peak at 12-d having leaves treated with MeSA.When P.Simonii ×P.Pyramibalis c.v leaves were exposed to MeJA or MeSA, the level of gallic acid, pyrocatechol and ferulic acid was increased; The catechinic acid and benzoic acid had a little drop; The caffeic acid and coumaric acid were undetected in both suffocated and control leaves.This changed pattern indicated that MeJA and MeSA can act as airborne signals to induce defense response of plants.
基金This work was supported by the Shandong Provincial Education Department Foundation (No. J05K04).
文摘Methyl jasmonate （MeJA） is a plant-signaling molecule that regulates plant morphogenesis and expression of plant defense genes. To determine the role of the endogenous MeJA levels in the development of plants, transgenic soybean [Glycine max （L.） Merrill] plants harboring NTR1 gene encoding for jasmonic acid carboxyl methyltransferase （JMT） were produced. The activation of NTR1 gene expression resulted in the production of MeJA. Overexpression of the NTR1 cDNA under the regulation of cauliflower mosaic virus （CaMV） 35S promoter in the transgenic soybean plants was confirmed using Northern blot analysis. The significant differences in leaf and root growth patterns were observed between the transgenic plants and the wild-type plants. The leaves of the transgenic plants were slightly elongated in length but dramatically narrowed in width compared with the nontrans-formed wild-type plants. In addition, elongation of primary root was inhibited in the overexpressed transgenic soybean plantlets, whereas the development of lateral root was stimulated relative to the nontransformed plants. The leaves of the transgenic plants showed 2-2.5-fold higher levels of MeJA than the control plants. These results indicated that the increased endogenous levels of MeJA is involved in regulation of morphogenesis in soybean plants.
基金Supported by Beijing Nature Science Foundation(5102015)~~
文摘[Objective]The aim was to explore the molecular mechanism of plant resistance to various stress response.[Method]The expression of LeWRKY1 in tomato seedlings under treatment with B.cinerea,exogenous JA and SA were explored by real time quantitative RT-PCR technology.[Result]JA induced the expression of LeWRKY1,but SA did not.LeWRKY1 expression was up-regulated under B.cinerea infection.[Conclusion]LeWRKY1 might be involved in the tomato defense response to B.cinerea through JA dependent but SA independent signal pathway.
基金supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,Education Ministry of China(2002-247)the Natural Science Foundation of Jiangsu Province,China(BK2001206).
文摘Zhaohui peaches(Prunus persica Batsch)were treated with 0(CK), 1, 10 or 100 μmol L-1 methyl jasmonate(MeJA)vapor at 20℃ for 24 h before stored at 0℃ for 35 d. The untreated fruits showed chilling injury(CD symptoms after 4 wk of storage, as indicated by increased fruit firmness and reduced ex-tractable juice, which is referred as leatheriness. Treatment with 1 and 10 μmol L-1 MeJA promoted normal ripening and softening, maintained higher levels of extractable juice, titratable acidity, pectinesterase(PE)and polygalacturonase(PC)activities, inhibited increases in fruit fresh weight loss, decay incidence, electrolyte leakage and MDA content, and improved color development, thereby preventing chilling injury symptoms development and maintaining edible quality. MeJA treatment also delayed the climacteric rise in respiratory rate, but promoted ethylene production during the later period of cold storage, suggesting that ethylene may involve in CI development of peaches. These results indicate that 1 and 10 μmol L-1 MeJA treatments could be used to reduce CI development and decay incidence in peaches.
