外用不同浓度茉莉酸甲酯诱导的茶树挥发物的种类和时序变化

【目的】明确MeJA对茶树挥发物的诱导作用。【方法】采用顶空活体取样法对不同浓度MeJA处理后的茶苗挥发物进行抽提,并利用GC-MS对挥发物进行鉴定。【结果】不同剂量MeJA显著地影响茶树挥发物的种类组成和释放量,50μL MeJA处理可显著诱导茶树释放香叶烯、萜品油烯、罗勒烯等10种单萜类化合物,法呢烯、橙花叔醇和红没药烯等7种倍半萜类化合物,苯甲醇、苯乙腈和吲哚等5种氨基酸衍生物,以及3种未知化合物;而100μL MeJA处理仅能诱导茶树释放7种化合物。不同挥发物对MeJA处理的响应时间不同,但其释放量都具有昼高夜低的趋势。并且,释放量的大小明显受到光照强度的影响。【结论】外用MeJA喷雾处理可诱导茶树挥发物的产生和释放。     

A robust sampling approach for identification and quantification of methyl jasmonate in leaf tissue of oilseed rape for analysis of early signaling in sclerotinia sclerotiorum resistance

Introduction – Methyl jasmonate (MJA), which is a natrual hormonal regulator, is thought to be essential for the regulation of systemic defence responses. The information about MJA levels in plant tissues is helpful for the study of the disease resistance mechanism and genetically engineered cultivars with increased resistance. Therefore, the quantification of MJA levels in plant tissues by means of a sensitive and reliable method is of interest. Objective – Development of a film extraction method coupled with GC for determination of methyl jasmonate in leaf tisssue of oilseed rape for analysis of early signalling in sclerotinia sclerotiorum resistance. Methodology – A robust polydimethylsiloxane film was prepared and used for extraction of MJA in leaf tissues. By using in‐solution extraction mode, optimum extraction efficiency was achieved with methanol–water (1 : 5, v/v) as extraction medium at 40°C for 60 min. Results – Under the optimal conditions, a detection limit of 0.2 ng/mL was achieved. Excellent reproducibility was found over a linear range of 1–1000 ng/mL. MJA in leaves infected by sclerotinia sclerotiorum was determined, with the results showing that basal levels of MJA (15 ng/g) were present in noninfested controls, but increased to 313 ng/g 10 h after fungal attack. Conclusion – The film extraction method is a simple, rapid and inexpensive sampling technique for determination of endogenous MJA in plant tissues that can be applied to most plants. Copyright © 2009 John Wiley & Sons, Ltd.     

Relationship of viability and apoptosis to taxol production in Taxus sp. suspension cultures elicited with methyl jasmonate

Taxus cuspidata P991 in plant cell suspension culture is capable of producing the important anticancer agent Taxol (paclitaxel) and related taxanes. High-level production is obtained by elicitation with methyl jasmonate, but successful elicitation leads to loss of cell viability that cannot be recovered by subculture. Here, we test whether the loss of viability is due to a direct effect of methyl jasmonate. Upon subculture, the reduced viability continued in methyl jasmonate elicited cultures, but not in nonelicited control cultures. The growth reduction in elicited T. cuspidata P991 suspension cultures was evaluated by viability reduction measurements using phenosafranin and fluorescein diacetate. The viability reduction does not appear to be related to apoptosis based on DNA laddering analysis because it occurred very late (at day 35) in the culture period. DNA laddering was also found only after day 28 in T. canadensis C93AD (a Taxol-producing cell line) elicited with methyl jasmonate, implying that apoptosis is not the major death mechanism after elicitation. As compared to Taxol-producing cell lines, the viability of a nonproducing cell line, T. canadensis CO93D, was not severely affected by methyl jasmonate, indicating that methyl jasmonate itself is not the primary factor for viability reduction. Based on Northern analysis of taxadiene synthase mRNA from both elicited and nonelicited T. cuspidata P991, methyl jasmonate directly induces the production of this enzyme, which is the first committed step in the biosynthetic pathway for Taxol. As a result, both viability reduction and growth reduction appear related to a high production level of Taxol (and related taxanes) upon methyl jasmonate elicitation, rather than to the direct effect of methyl jasmonate.     

前体饲喂、诱导子和光照联合使用对葡萄细胞培养合成花青素的影响

苯丙氨酸前体饲喂分别和环糊精、葡聚糖、茉莉酸甲酯、黑曲霉和直喙镰孢菌提取液五种诱导子联合作用,其中以与茉莉酸甲酯的联合作用对葡萄细胞培养生产花青素的影响最大,可使单位鲜细胞花青素含量提高2.7倍,花青素产量提高3.4倍,实验证明两者在培养后第4天加入效果最好。在30μmol/L苯丙氨酸、218μmol/L茉莉酸甲酯和3000~4000lx光照条件下,不同花青素产量的细胞株都能显著提高花青素产量,但低产株VV06比高产株VV05具有更大的产率提高潜力。该条件下VV05和VV06花青素产量分别达到2975和4090CV/L,是对照组的2.5倍和5.2倍。     

Modulation of carrier-mediated uptake of abscisic acid by methyl jasmonate in Phaseolus coccineus L

The effects of methyl jasmonate and jasmonic acid on uptake of abscisic acid (ABA) by suspension-cultured runner-bean cells and subapical runner-bean root segments have been investigated. Increasing concentrations of methyl jasmonate inhibit ABA uptake by the cultured cells with a K _i of 22±3 M. This is not due to cytoplasmic acidification or to effects on metabolism of ABA, and is not additive with inhibition of radioactive ABA uptake by nonradioactive ABA. Uptake of indol-3-yl acetic acid (IAA) is unaffected by methyl jasmonate. The maximum effect of nonradioactive ABA in inhibiting uptake of radioactive ABA, previously shown to reflect saturation of an ABA carrier, is generally greater than the effect of maximally inhibitory concentrations of methyl jasmonate. Similar results were obtained with root segments, but longer incubation times were necessary to observe inhibitory effects of methyl jasmonate. Demethylation of methyl jasmonate to jasmonic acid does not appear to be required since similar concentrations of jasmonic acid had no observable direct effect on ABA uptake other than that attributable to cytoplasmic acidification. Histidine reagents, a proton ionophore and acidic external pH all affect in parallel the inhibition by methyl jasmonate and nonradioactive ABA of uptake of radioactive ABA by the cultured cells. There is no effect of ABA or nonradioactive methyl jasmonate on uptake of radioactive methyl jasmonate by the cultured cells. It is proposed that methyl jasmonate interacts with the ABA carrier. Various models for this interaction are discussed.Abbreviations ABA abscisic acid - DMO 5,5-dimethyloxazolidine-2,4-dione - IAA indol-3-yl acetic acid     

Effect of volatile methyl jasmonate on the oxylipin pathway in tobacco, cucumber, and arabidopsis.

The effect of atmospheric methyl jasmonate on the oxylipin pathway was investigated in leaves of tobacco (Nicotiana tabacum L.), cucumber (Cucumis sativa L.), and Arabidopsis thaliana (L.). Differential sensitivities of test plants to methyl jasmonate were observed. Thus, different concentrations of methyl jasmonate were required for induction of changes in the oxylipin pathway. Arabidopsis was the least and cucumber the most sensitive to methyl jasmonate. Methyl jasmonate induced the accumulation of lipoxygenase protein and a corresponding increase in extractable lipoxygenase activity. Atmospheric methyl jasmonate additionally induced hydroperoxide lyase activity and the enhanced production of several volatile six-carbon products. It is interesting that lipid hydroperoxidase activity, which is a measure of hydroperoxide lyase plus allene oxide synthase plus possibly other lipid hydroperoxide-metabolizing activities, was not changed by methyl jasmonate treatment. Methyl jasmonate selectively altered the activity of certain enzymes of the oxylipin pathway (lipoxygenase and hydroperoxide lyase) and increased the potential of leaves for greatly enhanced six-carbon-volatile production.     

The effect of methyl jasmonate on accumulation of 2-phenylethylamine and putrescine in seedlings of common buckwheat (<Emphasis Type="Italic">Fagopyrum esculentum</Emphasis>)

The effects of exogenously applied methyl jasmonate on content of biogenic amines: putrescine, spermidine, tyramine, cadaverine and 2-phenylethylamine in seedlings of common buckwheat (Fagopyrum esculentum Moench) were investigated. The studies have shown that methyl jasmonate stimulates the conversion of l-phenylalanine into 2-phenylethylamine and increases the endogenous levels of putrescine in hypocotyls and cotyledons of buckwheat seedlings. Simultaneous feeding the seedlings with l-phenylalanine and methyl jasmonate has indicated that conversion of l-phenylalanine into 2-phenylethylamine can be one of possible reasons, caused by the methyl jasmonate suppression of anthocyanins synthesis in hypocotyls. To our knowledge, the stimulation of conversion of l-phenylalanine into 2-phenylethylamine by methyl jasmonate, as found in the present study, is described for the first time in higher plants.     

茉莉酮酸甲酯对水稻化感物质的诱导效应

在室内和田间条件下 ,外源茉莉酮酸甲酯均能显著地诱导水稻化感物质的合成 ,而且这种诱导效应与施用茉莉酮酸甲酯的浓度和诱导时间显著相关。 0 .4 m mol/L浓度和处理后 4 8h,茉莉酮酸甲酯对水稻化感物质的诱导效应最强。同样 ,不同的水稻品种对茉莉酮酸甲酯的诱导响应也有显著差异。水稻化感品种 PI312 777和丰华占在茉莉酮酸甲酯的诱导下能很快合成大量的化感物质 ,而水稻非化感品种华粳籼的化感物质的含量虽也有所增加 ,但达不到能显示化感作用的浓度。进一步实验证明 :茉莉酮酸甲酯在处理 4 8h后虽能诱导水稻品种合成大量的化感物质 ,但这一诱导效应并不能长期维持。研究揭示 :水稻化感物质的合成可在外部因子的作用下动态变化 ,这对揭示和充分利用水稻的化感作用机制有重要意义。     

Fungal elicitor preparations and methyl jasmonate enhance rosmarinic acid accumulation in suspension cultures of Coleus blumei

bstract Suspension cultures of Coleus blumei (Lamiaceae) treated with either an elicitor preparation from the culture medium of the phytopathogenic oomycete Pythium aphanidermatum or with methyl jasmonate enhanced accumulation of rosmarinic acid approximately threefold. The specific activities of phenylalanine ammonia lyase and rosmarinic acid synthase were also enhanced after addition of the fungal elicitor. The addition of methyl jasmonate transiently increased activities of phenylalanine ammonia lyase and hydroxyphenylpyruvate reductase, whereas the activity of rosmarinic acid synthase was not stimulated and the activity of tyrosine aminotransferase was slightly and constantly enhanced. Methyl jasmonate stimulated rosmarinic acid accumulation not only when added directly to the culture medium, but also when it could reach the cells only via the gas phase. Received: 2 April 1997 / Revision received:16 June 1997 / Accepted: 15 September 1997     

Jasmonate and ethylene signalling and their interaction are integral parts of the elicitor signalling pathway leading to beta-thujaplicin biosynthesis in Cupressus lusitanica cell cultures

Roles of jasmonate and ethylene signalling and their interaction in yeast elicitor-induced biosynthesis of a phytoalexin, beta-thujaplicin, were investigated in Cupressus lusitanica cell cultures. Yeast elicitor, methyl jasmonate, and ethylene all induce the production of beta-thujaplicin. Elicitor also stimulates the biosynthesis of jasmonate and ethylene before the induction of beta-thujaplicin accumulation. The elicitor-induced beta-thujaplicin accumulation can be partly blocked by inhibitors of jasmonate and ethylene biosynthesis or signal transduction. These results indicate that the jasmonate and ethylene signalling pathways are integral parts of the elicitor signal transduction leading to beta-thujaplicin accumulation. Methyl jasmonate treatment can induce ethylene production, whereas ethylene does not induce jasmonate biosynthesis; methyl jasmonate-induced beta-thujaplicin accumulation can be partly blocked by inhibitors of ethylene biosynthesis and signalling, while blocking jasmonate biosynthesis inhibits almost all ethylene-induced beta-thujaplicin accumulation. These results indicate that the ethylene and jasmonate pathways interact in mediating beta-thujaplicin production, with the jasmonate pathway working as a main control and the ethylene pathway as a fine modulator for beta-thujaplicin accumulation. Both the ethylene and jasmonate signalling pathways can be regulated upstream by Ca(2+). Ca(2+) influx negatively regulates ethylene production, and differentially regulates elicitor- or methyl jasmonate-stimulated ethylene production.     

Nitrogen storage and remobilization in Brassica napus L. during the growth cycle: identification, characterization and immunolocalization of a putative taproot storage glycoprotein.

In taproot of oilseed rape (Brassica napus L.), a 23 kDa polypeptide has been recently identified as a putative vegetative storage protein (VSP) because of its accumulation during flowering and its specific mobilization to sustain grain filling when N uptake is strongly reduced. The objectives were to characterize this protein more precisely and to study the effect of environmental factors (N availability, daylength, temperature, water deficit, wounding) or endogenous signals (methyl jasmonate, abscisic acid) that might change the N source/sink relationships within the plant, and may therefore trigger its accumulation. The 23 kDa putative VSP has two isoforms, is glycosylated and both isoforms share the same N-terminal sequence which had been used to produce specific polyclonal antibodies. Low levels of an immunoreactive protein of 24 kDa were found in leaves and flowers. In taproot, the 23 kDa putative VSP seems to accumulate only in the vacuoles of peripheral cortical parenchyma cells, around the phloem vessels. Among all treatments tested, the accumulation of this protein could only be induced by abscisic acid and methyl jasmonate. When compared to control plants, application of methyl jasmonate reduced N uptake by 89% after 15 d, induced a strong remobilization of N from senescing leaves and a concomitant accumulation of the 23 kDa putative VSP. These results suggested that, in rape, the 23 kDa protein is used as a storage buffer between N losses from senescing leaves promoted by methyl jasmonate and grain filling.     

Methyl jasmonate conditions parsley suspension cells for increased elicitation of phenylpropanoid defense responses.

Pre-incubation of suspension-cultured parsley cells with methyl jasmonate greatly enhances their ability to respond to fungal elicitors by secretion of coumarin derivatives. The effect is most pronounced at relatively low elicitor concentration and also observed for the incorporation of esterified hydroxycinnamic acids and of "lignin-like" polymers into the cell wall. These three responses correspond to defense reactions induced locally when a fungal pathogen attacks plant cells. In contrast, the conditioning of parsley cells by the signal substance methyl jasmonate is reminiscent of the developmental nature of systemic acquired resistance and renders the cells more effective for the elicitor-induced local defense reactions.     

Inhibitory effect of methyl jasmonate and its related compounds on kinetin-induced retardation of oat leaf senescence

The senescence-promoting activities of methyl jasmonate and its related compounds were compared with respect to structure-activity relationships. The activities were assayed by using oat ( A vena saliva L. cv. Victor) leaf segments in the presence of 2 μg/ml kinetin. Dextrorotatory methyl jasmonate prepared from an authentic sample of the racemate mixture was less active than the naturally occurring levorotatory form especially at its low concentrations (0.1 to 2.5 μg/ml). The activity of jasmonic acid, the free acid form of methyl jasmonate, was much less than the methyl ester, and this relationship was true for the other compounds tested. The reduction of the unsaturated bond in the substituent at the C-2 position and the keto group at the C-3 position greatly reduced the activity. The length of the n -alkyl substituents at the C-2 position had also a significant effect on the activity. From these results, it is concluded that the important functional groups for the high senescence-promoting activity of the methyl jasmonate related compounds are the methyl acetate substituent at the C-l position, the 2' cis -pentenyl or n -pentyl group at the C-2, position and the keto group at the C-3 position in methyl jasmonate.     

Methyl jasmonate affects phenolic metabolism and gene expression in blueberry (Vaccinium corymbosum)

Blueberry (Vaccinium corymbosum) is a fruit very much appreciated by consumers for its antioxidant potential and health‐promoting traits. Its beneficial potential properties are mainly due to a high content of anthocyanins and their amount can change after elicitation with methyl jasmonate. The aim of this work is to evaluate the changes in expression of several genes, accumulation of phenolic compounds and alterations in antioxidant potential in two different blueberry cultivars (‘Duke’ and ‘Blueray’) in response to methyl jasmonate (0.1 mM). Results showed that 9 h after treatment, the expression of phenylalanine ammonium lyase, chalcone synthase and anthocyanidin synthase genes was stimulated more in the ‘Blueray’ variety. Among the phenols measured an increase was recorded also for epicatechin and anthocyanin concentrations. ‘Duke’ is a richer sourche of anthocyanins compared to ‘Blueray’, treatment with methyl jasmonate promoted in ‘Blueray’ an increase in pigments as well as in the antioxidant potential, especially in fully ripe berries, but treated ‘Duke’ berries had greater levels, which were not induced by methyl jasmonate treatment. In conclusion, methyl jasmonate was, in some cases, an effective elicitor of phenolic metabolism and gene expression in blueberry, though with different intensity between cultivars.     

Effects of elicitation on the production of saponin in cell culture of Panax ginseng

This study was initiated to investigate the impacts of elicitor concentration and elicitor-adding time on the saponin synthesis and the cell growth of Panax ginseng cell suspensions. Both of the elicitors tested, yeast extract and methyl jasmonate, significantly improved saponin production. The highest additive level of the seven ginsenosides tested was 2.07% (dry weight basis), which was 28-fold higher than that in the control. The optimum time to add either elicitor was found to be on the day of inoculation. The addition of either elicitor did not show as significant an influence on cell growth as on saponin production. It was advisable to remove 2,4-dichlorophenoxyacetic acid (2,4-D) from the medium when methyl jasmonate was used as the elicitor as methyl jasmonate interacts antagonistically with 2,4-D. These results suggest that the addition of an elicitor to ginseng cell suspension cultures could stimulate saponin production.     

Enhancement of phytosterols, taraxasterol and induction of extracellular pathogenesis-related proteins in cell cultures of Solanum lycopersicum cv Micro-Tom elicited with cyclodextrins and methyl jasmonate

Suspension-cultured cells of Solanum lycopersicum cv Micro-Tom were used to evaluate the effect of methyl jasmonate and cyclodextrins, separately or in combination, on the induction of defense responses. An extracellular accumulation of two sterols (isofucosterol and β-sitosterol) and taraxasterol, a common tomato fruit cuticular triterpene, were observed. Their levels were higher in Micro-Tom tomato suspension cultured cells elicited with cyclodextrins than in control and methyl jasmonate-treated cells. Also, their accumulation profiles during the cell growth phase were markedly different. The most striking feature in response to cyclodextrin treatments was the observed enhancement of taraxasterol accumulation. Likewise, the exogenous application of methyl jasmonate and cyclodextrins induced the accumulation of pathogenesis-related proteins. Analysis of the extracellular proteome showed the presence of amino acid sequences homologous to pathogenesis-related 1 and 5 proteins, a cationic peroxidase and a biotic cell death-associated protein, which suggests that methyl jasmonate and cyclodextrins could play a role in mediating defense-related gene product expression in S. lycopersicum cv Micro-Tom.     

Exogenous application of methyl jasmonate elicits defenses in Norway spruce (Picea abies) and reduces host colonization by the bark beetle Ips typographus

The terpenoid and phenolic constituents of conifers have been implicated in protecting trees from infestation by bark beetles and phytopathogenic fungi, but it has been difficult to prove these defensive roles under natural conditions. We used methyl jasmonate, a well-known inducer of plant defense responses, to manipulate the biochemistry and anatomy of mature Picea abies (Norway spruce) trees and to test their resistance to attack by Ips typographus (the spruce bark beetle). Bark sections of P. abies treated with methyl jasmonate had significantly less I. typographus colonization than bark sections in the controls and exhibited shorter parental galleries and fewer eggs had been deposited. The numbers of beetles that emerged and mean dry weight per beetle were also significantly lower in methyl jasmonate-treated bark. In addition, fewer beetles were attracted to conspecifics tunneling in methyl jasmonate-treated bark. Stem sections of P. abies treated with methyl jasmonate had an increased number of traumatic resin ducts and a higher concentration of terpenes than untreated sections, whereas the concentration of soluble phenolics did not differ between treatments. The increased amount of terpenoid resin present in methyl jasmonate-treated bark could be directly responsible for the observed decrease in I. typographus colonization and reproduction.     

Methyl jasmonate vapor increases the developmentally controlled synthesis of alkaloids in Catharanthus and Cinchona seedlings

Shortly after germination, alkaloids are rapidly synthesized in seedlings of both Catharanthus roseus L.G. Don and Cinchona ledgeriana Moens. The effect of low-level, atmospheric methyl jasmonate on this developmentally controlled process was studied. In both species, about 1 p.p.m. of methyl jasmonate vapor significantly enhanced alkaloid synthesis during germination, resulting in a doubling of alkaloid content in seedlings. Treatment with methyl jasmonate resulted in increased allocation of alkaloid precursors and in enhanced enzyme activities in alkaloid biosynthesis. The ability of methyl jasmonate to increase alkaloid biosynthesis decreased with age of the seedlings. Susceptibility of the process to methyl jasmonate was confined to a narrow time interval where the developmentally regulated onset of alkaloid synthesis occurred. When methyl jasmonate was applied at later developmental stages, its ability to enhance alkaloid content in the seedlings declined sharply.     

Expression profiling of metabolic genes in response to methyl jasmonate reveals regulation of genes of primary and secondary sulfur-related pathways in Arabidopsis thaliana

The treatment of Arabidopsis thaliana with methyl jasmonate was used to investigate the reaction of 2467 selected genes of primary and secondary metabolism by macroarray hybridization. Hierarchical cluster analysis allowed distinctions to be made between diurnally and methyl jasmonate regulated genes in a time course from 30 min to 24 h. 97 and 64 genes were identified that were up- or down-regulated more than 2–fold by methyl jasmonate, respectively. These genes belong to 18 functional categories of which sulfur-related genes were by far strongest affected. Gene expression and metabolite patterns of sulfur metabolism were analysed in detail, since numerous defense compounds contain oxidized or reduced sulfur. Genes encoding key reactions of sulfate reduction as well as of cysteine, methionine and glutathione synthesis were rapidly up-regulated, but none of the known sulfur-deficiency induced sulfate transporter genes. In addition, increased expression of genes of sulfur-rich defense proteins and of enzymes involved in glucosinolate metabolism was observed. In contrast, profiling of primary and secondary sulfur metabolites revealed only an increase in the indole glucosinolate glucobrassicin upon methyl jasmonate treatment. The observed rapid mRNA changes were thus regulated by a signal independent of the known sulfur deficiency response. These results document for the first time how comprehensively the regulation of sulfur-related genes and plant defense are connected. This interaction is discussed as a new approach to differentiate between supply- and demand-driven regulation of the sulfate assimilation pathway.     

The effect of methyl jasmonate and abscisic acid on differentiation of benzyladenine-induced bulblets inMuscari bulbs

Methyl jasmonate (JA-Me) at a concentration of 0.5% in lanolin paste totally inhibited bulblets formation induced by benzyladenine in intactMuscari bulbs. Lower concentrations of JA-Me delayed development and growth of bulblets induced by benzyladenine. It seems that methyl jasmonate acts as a powerful inhibitor of cell division induced by cytokinin in used test. In comparison with methyl jasmonate, abscisic acid did not show an inhibitory effect on bulblets formation induced by benzyladenine, even in a higher concentration.