Influence Of Methyl Jasmonate Research Articles

The SmMYC2-SmMYB36 complex is involved in methyl jasmonate-mediated tanshinones biosynthesis in Salviamiltiorrhiza.

The jasmonic acid (JA) signaling pathway plays an important role in promoting the biosynthesis of tanshinones. While individual transcription factors have been extensively studied in the context of tanshinones biosynthesis regulation, the influence of methyl jasmonate (MeJA)-induced transcriptional complexes remains unexplored. This study elucidates the positive regulatory role of the basic helix-loop-helix protein SmMYC2 in tanshinones biosynthesis in Salvia miltiorrhiza. SmMYC2 not only binds to SmGGPPS1 promoters, activating their transcription, but also interacts with SmMYB36. This interaction enhances the transcriptional activity of SmMYC2 on SmGGPPS1, thereby promoting tanshinones biosynthesis. Furthermore, we identified three JA signaling repressors, SmJAZ3, SmJAZ4, and SmJAZ8, which interact with SmMYC2. These repressors hindered the transcriptional activity of SmMYC2 on SmGGPPS1 and disrupted the interaction between SmMYC2 and SmMYB36. MeJA treatment triggered the degradation of SmJAZ3 and SmJAZ4, allowing the SmMYC2-SmMYB36 complex to subsequently activate the expression of SmGGPPS1, whereas SmJAZ8 inhibited MeJA-mediated degradation due to the absence of the LPIARR motif. These results demonstrate that the SmJAZ-SmMYC2-SmMYB36 module dynamically regulates the JA-mediated accumulation of tanshinones. Our results reveal a new regulatory network for the biosynthesis of tanshinones. This study provides valuable insight for future research on MeJA-mediated modulation of tanshinones biosynthesis.

Influence of methyl jasmonate and methyl jasmonate plus urea foliar applications on amino acids composition throughout ‘Tempranillo’ grape ripening over two seasons

This work studies the impact of foliar application of methyl jasmonate (MeJA) and methyl jasmonate plus urea (MeJA + Ur) on the evolution of amino acid content in ‘Tempranillo’ grapes during ripening, across two vintages. To achieve this goal, sample grapes were harvested at five different timing. Fol1: 1 day before first foliar application; Fol2: 1 day before second foliar application; Preharvest: 15 days after second foliar application; Harvest: the day of harvest; and Postharvest: 15 days after harvest. The effect of foliar treatments was season dependent, being effective to improve the amino acids content of grapes only in the first vintage. Among the treatments studied, foliar application of MeJA-Ur showed better results. The evolution of amino acids during ripening also was different among seasons. Overall, in the 2019, amino acids reached their highest content at Preharvest or Harvest samples, whereas in the 2020 season, these highest concentrations were reached at Postharvest. Asparagine might serve as a suitable amino acid for controlling grape ripening, as its content decreased from Fol1 to Postharvest in the two vintages. Moreover, differences on the total amino acids content at Harvest date between vintages were observed, probably due to different climatological conditions. Therefore, this study pioneers the examination of the impact of foliar applications of MeJA and MeJA + Ur on the amino acids evolution in ‘Tempranillo’ grapes during ripening. The need for further research is clear to comprehend the complex interaction between foliar treatments and grape amino acids dynamics for optimizing nitrogen quality of grapes.

Methyl Jasmonate Elicitation for In Vitro Lycorine Accumulation in Three Zephyranthes Species and Comparative Analysis of Tissue-Cultured and Field Grown Plants

Lycorine is an important Amaryllidaceae alkaloid showing anti-cancerous activity on numerous cell lines; and it also demonstrates antiviral activity against several viruses including SARS-CoV-2 responsible for COVID-19. The in vitro cultivation of plant parts is a good alternative for elicitor mediated secondary metabolite synthesis, mass propagation, and cloning of elite genotypes. In this study, the quantification of lycorine from Zephyranthes candida, Zephyranthes grandiflora, and Zephyranthes citrina was evaluated, and the influence of methyl jasmonate (MJ) treatments on accumulation of lycorine yield was observed in the in vitro cultivated tissues. The influence of methyl jasmonate (MJ) on accumulation of lycorine was investigated for the first time in in vitro regenerated bulb, leaf, and root tissues of Zephyranthues. The efficient in vitro shoot regeneration was achieved in Z. candida (73.9%), Z. grandiflora (85.5%), and Z. citrina (76.5%) on Murashige and Skoog (MS) medium amended with 2.0 mg·L−1 Naphthalene acetic acid + 0.5 mg·L−1 Benzylaminopurine. The regenerants had the highest i.e., 7.46 mean numbers of bulblets per shoot. The best root induction (80.66%) was achieved on 2.0 mg/L Indole butyric acid (IBA). The lycorine content was quantified through High performance thin layer chromatography (HPTLC) in three field grown Zephyranthes species, was highest in Z. candida (1.93 µg g−1 dry wt.), followed by Z. grandiflora (1.87 µg g−1 dry wt.) and Z. citrina (1.62 µg g−1 dry wt.). The yield of lycorine was observed in this order i.e., bulb > leaf > root. The regenerated plants were supplemented with MJ and maximum lycorine yield was noted at 100 µM in bulb tissues of Z. candida (2.74 µg g−1 dry wt.) with an increase in percentage of 39.08. The enhancement could be due to MJ-induced stress as the biochemical attributes and anti-oxidant enzyme activity were high with elevated level of MJ. This enrichment may auger commercial manufacturing and utilization of lycorine in future.

The Influence of Methyl Jasmonate on Expression Patterns of Rosmarinic Acid Biosynthesis Genes, and Phenolic Compounds in Different Species of Salvia subg. Perovskia Kar L.

Salvia yangii B.T. Drew and Salvia abrotanoides Kar are two important fragrant and medicinal plants that belong to the subgenus Perovskia. These plants have therapeutic benefits due to their high rosmarinic acid (RA) content. However, the molecular mechanisms behind RA generation in two species of Salvia plants are still poorly understood. As a first report, the objectives of the present research were to determine the effects of methyl jasmonate (MeJA) on the rosmarinic acid (RA), total flavonoid and phenolic contents (TFC and TPC), and changes in the expression of key genes involved in their biosynthesis (phenylalanine ammonia lyase (PAL), 4-coumarate-CoA ligase (4CL), and rosmarinic acid synthase (RAS)). The results of High-performance liquid chromatography (HPLC) analysis indicated that MeJA significantly increased RA content in S. yungii and S. abrotanoides species (to 82 and 67 mg/g DW, respectively) by 1.66- and 1.54-fold compared with untreated plants. After 24 h, leaves of Salvia yangii and Salvia abrotanoides species treated with 150 M MeJA had the greatest TPC and TFC (80 and 42 mg TAE/g DW, and 28.11 and 15.14 mg QUE/g DW, respectively), which was in line with the patterns of gene expression investigated. Our findings showed that MeJA dosages considerably enhanced the RA, TPC, and TFC contents in both species compared with the control treatment. Since increased numbers of transcripts for PAL, 4CL, and RAS were also detected, the effects of MeJA are probably caused by the activation of genes involved in the phenylpropanoid pathway.

Influence of Methyl Jasmonate and Salicylic Acid as Components of the Cultivation Medium for Rhizobium on Formation of Different-Efficiency Symbiotic Systems Glycine max — Bradyrhizobium japonicum

Phytohormones are important in the main pathways of transduction of symbiotic signals between macro- and microsymbionts, and understanding of their participation in integration with other metabolic pathways, including prooxidant-antioxidant systems, is crucial in the formation of different-efficiency symbiotic systems. Aim. To investigate the effect of salicylic acid (SA, 50 μM) and methyl jasmonate (MJ, 0.75 μM) as components of the cultivation media of different in the activity and virulence rhizobia 604k and B1-20 on the peculiarities of the formation of symbiotic systems in terms of intensity and activity of catalase, as well as on the course of nodulation and nitrogen fixation. Methods. Microbiological (cultivation of nitrogen-fixing microorganisms, seed inoculation), physiological (vegetation experiment), biochemical (spectrophotometry, gas chromatography), and statistical. Results. It was found that the use of SA (50 μM) as an additional component of the culture medium of active rhizobia Tn5-mutant B1-20 for seed inoculation induces increased levels of peroxide production and catalase activity in soybean roots in the early stages of symbiosis, which contributes to the effectiveness of its symbiotic apparatus. Addition of MJ (0.75 μM) to the culture medium of rhizobia B1-20 does not affect changes in peroxide content and catalase activity in the roots, however, stimulates the processes of nodulation and reduces nitrogen fixation. It has been shown that modification of the cultivation medium of inactive rhizobia of the highly virulent strain 604k using SA (50 μM) or MJ (0.75 μM) does not change the peroxide content and leads to an increase in catalase activity in soybean roots during the formation of an ineffective symbiotic system with activation of nodulation processes. Conclusions. When using SA (50 μM) or MJ (0.75 μM) as components of the culture medium for rhizobia of different activity and virulence (604k and B1-20), differences were recorded in the levels of functioning of pro-antioxidant systems, in particular, in the production of peroxides and active catalase complexes, at the early stages of the formation of symbiotic systems of Glycine max — Bradyrhizobium japonicum, which affects the intensity of the processes of nodulation and nitrogen fixation.

Analysis of the initial response pattern of <italic>Chlamydomonas reinhardtii</italic> to methyl jasmonate (MeJA) treatment

As a chemical elicitor of plants, methyl jasmonate (MeJA) is a regulator of many secondary metabolisms in plants, which participates in the regulation of isoprenoid metabolism and has an important impact on the synthesis of isoprenoids in <italic>Chlamydomonas reinhardtii</italic> (<italic>C. reinhardtii</italic>). In order to explore how <italic>C. reinhardtii</italic> responds rapidly to MeJA treatment, the physiological parameters such as growth rate and photosynthetic efficiency of <italic>C. reinhardtii</italic> under MeJA treatment were measured. The changes in the expression levels of key genes in the 2-C-methnatureyl-D-rythritol-4-phosphate (MEP) pathway and in the carotenoid and sterol synthesis pathway within 24 hours of MeJA treatment were focused. The results showed that MeJA treatment dramatically reduced biomass accumulation and photosynthetic activity of <italic>C. reinhardtii</italic>, prominently activated the expression of key genes in MEP pathway and sterol synthesis, inhibited key genes of carotenoid synthesis pathway. The results at the transcriptional and physiological levels suggested that the influence of MeJA on <italic>C. reinhardtii</italic> was rapid and dose-dependent. This study provides a theoretical reference for exploring the mechanism of isoprene synthesis and metabolism in microalgae.

Near-harvest application of methyl jasmonate affected phenolic content and antioxidant properties in "Thompson Seedless" grape.

The influence of methyl jasmonate (MJ) preharvest treatment was investigated on some polyphenols and antioxidant systems in the “Thompson Seedless” table grape. The clusters were sprayed in the vineyard 2 days before harvest with 0, 1, 5, and 10 mM MJ. After picking, berries were stored for 6 days at 15°C, simulating marketing conditions. Total phenols and flavonoids were affected by MJ treatment, especially at 10 mM concentration, whereas total tannins were found to be unchanged. Antioxidant activity of the treated skin was noticeably higher compared with the control, together with PAL and POD activity. Although MJ had little effect on catechin and epicatechin, the levels of quercetin and rutin were noticeable. In addition, 5 and 10 mM MJ exerted a pronounced effect on transresveratrol content. These data showed that a single preharvest application close to the harvest time could be an effective treatment to promote the antioxidant properties of the grape.

Methyl jasmonate alleviates the reduced release of aroma‐related esters in ‘Nanguo’ pears by regulating ethylene biosynthesis and signal transduction

SummaryCryopreserved fruits usually develop symptoms, which affects the release of aroma. Our study investigated the impact of exogenous methyl jasmonate (MeJA) upon the synthesis of aromatic esters in ‘Nanguo’ pears after cold storage. It found that exogenous MeJA enhanced ethylene accumulation via improving the activity of 1‐aminocyclopropane‐1‐carboxylic‐acid (ACC) synthase (ACS) and ACC oxidase (ACO) and the expression levels of PuACS1 and PuACO1. After cryopreservation for 90 days, the ester aroma of ‘Nanguo’ pears was effectively improved by MeJA during normal temperature shelf life. In addition, the expression of PuERS1, PuETR1, PuEIN4, PuEIN2 and PuERF1 in MeJA‐treated fruits were obviously increased. Therefore, we infer that the influence of MeJA on production of aroma‐related esters in ‘Nanguo’ pears is closely connected with ethylene biosynthesis and signal transduction, namely increase activity of ACS and ACO, and upregulation of the expression level of PuACS1, PuACO1, PuERS1, PuETR1, PuEIN2, PuEIN4 and PuERF1.

INDUCED RESISTANCE AND DIFFERENTIAL ALLOCATION OF HERBIVORE DEFENSIVE CHEMICALS: A CASE STUDY WITH INTERNODE BORER CHILO SACCHARIPHAGUS INDICUS (KAPUR) IN SUGARCANE

Methyl jasmonate (MeJA), a known resistance inducer molecule, when applied was found to give protection against the attack of internode borer (INB) Chilo sacchariphagus indicus (Kapur) (Lepidoptera: Crambidae) in sugarcane to the extent of 86.67% as against 73.33% damage in control plants. Estimation of 12 phenolic compounds in leaf and stem tissues, following external application of 100 ppm MeJA, indicated wide variation with a 19-fold higher production in leaf than in stem tissue implying differential allocation of these chemicals within by the plant. Among all the phenolics, ferulic acid was expressed at the highest levels in both leaf and stem tissues. Such differential allocation of defensive chemicals is resorted to by the host plant to economize its resources by directing the chemicals to the site of initial attack, i.e. leaf tissue in the present case, rather than systemically deploying throughout the plant. From the observations, reduced INB attack and production of phenolics under the influence of MeJA, it is hypothesized that plant recognizes feeding by herbivores in their early stages and triggers differential production of defensive chemicals to target the early and vulnerable stage of the pest to limit losses.

Methyl jasmonate improves metabolism and growth of NaCl-stressed Glycyrrhiza uralensis seedlings

Background and AimsSalinity is one of the major factors that affect growth and metabolism in plants. However, limited information is available on the influence of methyl jasmonate (MeJA) on antioxidant defense, carbon (C) and nitrogen (N) metabolisms in Glycyrrhiza uralensis Fisch. (G. uralensis) under salt stress. Here, this experiment was conducted to investigated the responses of antioxidant defense, C and N metabolisms of salt-stressed G. uralensis to MeJA at different concentrations. MethodsG.uralensis plant seeds were grown under six conditions: control, 200 mM NaCl, and 200 mM NaCl combined with 15, 30, 45 and 60 μM MeJA. Key ResultsResults showed that salt stress inhibited G. uralensis growth and this adverse effect was reversed by MeJA at different concentrations. MeJA also affected antioxidant system and C and N metabolisms. In general, MeJA from 45 to 60 μM significantly enhanced superoxide dismutase (SOD), ascorbate peroxidase (APX) and glutathione peroxidase (GPX) activities in salt-stressed G. uralensis seedlings, MeJA from 15 to 30 μM increased peroxidases (POD) and catalase (CAT) activities, and ascorbate peroxidase (AsA) and glutathione (GSH) contents. Thus, these changes caused a decrease in hydrogen peroxide (H2O2), superoxide radical (O2−) and malondialdehyde (MDA) contents correspondingly. Moreover, 60 μM MeJA enhanced sucrose synthase (SS), sucrose phosphate synthase (SPS) and nitrate reductase (NR) activities in salt-stressed G. uralensis seedlings. ConclusionsMeJA promoted growth of salt-stressed G. uralensis seedlings by alleviating oxidative stress and strengthening C and N metabolism, these effect depended on the applied concentrations of MeJA.

Influence of Methyl Jasmonate on Production of Ecdysteroids from Hairy Roots of Silene linicola C.C. Gmelin

Hairy roots cultures are being considered as a promising system for producing valuable second metabolites. These genetically transformed root cultures are characterized by high growth rate, genetic stability and growth in hormone free media. Using A. rhizogenes-mediated transformation method (strain А4), we have obtained hairy roots cultures of the ecdysteroid-containing species of Silene linicola. HPLC analysis of the sample studied revealed that 20-hydroxyecdysone (20E), turkesterone and polypodin B were synthesized under the specified experimental conditions. Application of methyl jasmonate at a concentration of 100 μM resulted in stimulation of 20E biosynthesis (up 74%) after three days of cultivation and turkesterone up to 35% at six days. It was noted that total ecdysteroid content in sample tested varied: turkesterone from 25 to 60%, and 20E from 8 to 30%. At the same time, the level of 20E biosynthesis decreased from 0.023 to 0.014% in the samples without methyl jasmonate treatment. Hairy roots lines of S. linicola with different responses to the presence of elicitors in the culture medium can be used to study the pathways of ecdysteroid biosynthesis.

Influence of methyl jasmonate and benzothiadiazole on the composition of grape skin cell walls and wines.

Phenolic compounds are very important in crop plants, particularly in grapes. The different strategies to increase their levels include the use of elicitors such as methyl jasmonate (MeJ) and benzothiadiazole (BTH). In an attempt to improve the quality of wines, our aim was to evaluate the effect of preharvest application of these elicitors on the composition and structure of the skin cell walls of Monastrell, Merlot and Cabernet Sauvignon grapes, and to ascertain any relationship with the extractability of phenolic compounds during winemaking. The results indicated that the exogenous application of MeJ and BTH during veraison caused significant changes in several components of the skin cell walls, such as phenolic compounds, proteins and structural sugars. However these changes manifested themselves in different proportions in each variety and year, pointing to the varietal and meteorological dependence of the response to the application of these elicitors. The treatments delayed the maturation process in all varieties when rainfall was low. This observation, together with the observed increase in proteins and phenols in the skin cell wall of Monastrell and Cabernet Sauvignon, could contribute to the strength necessary to maintain the integrity of berries and to increasing resistance to fungal pathogens as the phenolic compounds evolve, thus improving the phenolic profile. However, the structural integrity of Merlot variety tended to decrease in the same conditions.

Influence of methyl jasmonate on ginsenoside biosynthesis in suspension cultures of Panax quinquefolium L.

&lt;p&gt;Panax quinquefolium L., belonging to the Araliaceae family, along with P. ginseng is one of the well-known species of ginseng. Multidirectional pharmacological action of this plant is attributed to triterpene saponins called ginsenosides. Pharmacopoeial raw material are roots obtained from the field crops which are time-consuming and require expensive agrotechnical procedures. Therefore, the new sources of ginseng biomass are sought such as in vitro suspension cultures. P. quinquefolium L. cell cultures, treated with the elicitation of methyl jasmonate (MJ) in concentration 50 and 250 μmol L-1, synthesize more ginsenosides than control cultures. The highest increase (2.2-fold) of all examined compounds was noted using 250 μmol L-1 MJ. In this condition, the predominantly quantitative metabolite was Rb1 ginsenoside belonging to protopanaxadiol derivatives.&lt;/p&gt;

The Influence of Methyl Jasmonate on Growth and Caffeic Acid Derivative Contents of In vitro Shoot and Roots in Echinaceae (Echinacea Purpurea)

Abstract: This study was carried out to determine the effects of methyl jasmonate (MeJA) applications on growth and accumulation of caffeic acid derivatives (CADs) in shoots and roots grown in vitro. For this aim, 28 days old plants obtained from seeds were cultured in ½ Murashige and Skoog media containing different concentrations of MeJA (0, 10, 50 and 100 μM) and plants were harvested in three times at 15 days intervals. After harvest, growth parameters and CADs in shoot and roots were determined, separately. All growth parameters decreased in line with the elevating level of MeJA applications. But MeJA applications increased the CADs both shoots and roots compared to the controls. The highest cichoric acid, the main CAD of Echinacea, was found in shoots and roots applied with 100 μM MeJA and harvested in 45 days after application. Key words: Echinacea Purpurea, Methyl Jasmonate, Caffeic Acid Derives, Cichoric Acid

Methyl jasmonate treatment increases podophyllotoxin production in Podophyllum hexandrum roots under glasshouse conditions

Background and aimThe endangered Podophyllum hexandrum is an important industrial source of podophyllotoxin, which is a precursor for the anticancer drugs etoposide and teniposide. Attempts to obtain podophyllotoxin through cell cultures or chemical synthesis have still a long way to go before being economical feasible. The objective of this study was to increase the root formation and podophyllotoxin production of P. hexandrum cultivated in a glasshouse.MethodsRoot formation and podophyllotoxin production of P. hexandrum in sand or peat-perlite soil at 15 °C or 25 °C was determined. Furthermore, the influence of methyl jasmonate on the podophyllotoxin production was determined.ResultsMore root formation was observed in peat-perlite soil than in sand soil. Furthermore, root formation was higher at 15 °C than at 25 °C. This resulted in the highest podophyllotoxin production per plant in peat-perlite at 15 °C (160 ± 22 mg/plant d.w.). Furthermore, methyl jasmonate treatment of the leaves increased the podophyllotoxin production in the roots by 21%.ConclusionWe were able to cultivate P. hexandrum in a glasshouse in the Netherlands and improve the root formation and podophyllotoxin production. This paves the way for large-scale cultivation of P. hexandrum in the temperate latitudes for the production of the pharmaceutical interesting podophyllotoxin.

The influence of methyl jasmonate on the biosynthesis of phospholipids in germinating yellow lupine seeds

The influence of methyl jasmonate on the biosynthesis of phospholipids in germinating yellow lupine seeds

The Influence of Methyl Jasmonate and Salicylic Acid on Secondary Metabolite Production in Rehmannia Glutinosa Libosch. Hairy Root Culture

Abstract Rehmannia glutinosa hairy roots were used to evaluate the effect of methyl jasmonate (MeJa) and salicylic acid (SA) on increase of root biomass and production of iridoids (catalpol, harpagide) and phenylethanoids (verbascoside and isoverbascoside). The elicitors were added to 23-day-old culture separately at concentrations between 50 and 200 μM or in combinations at concentrations of 50 and 100 μM. Roots were harvested 72 h and 120 h after elicitation. The type of elicitor, its concentration and exposure time were found to strongly affect the content of each analyzed compound. A 72-hour treatment with 200 μM MeJa was the most effective in increase of verbascoside content (60.07 mg·DW−1 equivalent to 845.45 mg·L−1) and isoverbascoside (1.77 mg·DW−1 equivalent to 24.94 mg·L−1): these respective amounts were roughly 10- and 6.4-fold higher than the control values (unelicited roots). Exposure to 150 μM MeJa provided optimal harpagide content after 72 hours (0.136 mg·DW−1; 7.5-fold increase compared to the control), and catalpol content after 120 hours (up to 2.145 mg·DW−1). The combination of MeJa and SA also resulted in higher levels of secondary metabolites compared to the control culture, although these levels were lower than those observed for MeJa alone at the optimal concentration and exposure time. SA alone was less efficient in enhancing metabolite production than MeJa.

Methyl Jasmonate Elicitation Affects Expression of Genes Involved in Biosynthesis and Turnover of 2-Phenylethylamine in Maize Seedlings

Abstract The objective of the study was to assess the influence of methyl jasmonate (MJ) vapors on accumulation of 2-phenylethylamine (PEA), phenylacetic acid (PAA) and 2-phenylethanol (PE) in leaves and roots of maize (Zea mays L. subsp. mays, saccharata group, cv. Złota Karłowa) seedlings. Furthermore, we analyzed the expression patterns of eight genes (ADH1, ADH2, AO2, CAO, PDC1, PDC2, PTA and LOX, encoding alcohol dehydrogenase 1 and 2, primary amine oxidase, aldehyde oxidase 2, phenylalanine decarboxylase 1 and 2, phenylalanine (histidine) transaminase and lipoxygenase, respectively) involved in biosynthesis and turnover of PEA in maize tissues. In addition, the effect of MJ application on fresh biomass and growth of the tested seedlings was recorded. One-day MJ exposure increased the fresh weight of aerial parts and roots of Z. mays seedlings, whereas the opposite tendency occurred after 4-day of MJ treatment. One-day application of MJ resulted in an increase in the length of roots and its fluctuations in the aerial parts of maize plants, but extended exposure declined the growth of both parts of the seedlings. Methyl jasmonate elicitation caused various changes in the contents of PEA, PAA and PE in the maize seedlings. MJ treatments led to high upregulation of most genes, with the exception of three genes (i.e., ADH1, ADH2 and AO2) whose expression was downregulated after a 4-day exposure.

Methyl Jasmonate: An Alternative for Improving the Quality and Health Properties of Fresh Fruits.

Methyl jasmonate (MeJA) is a plant growth regulator belonging to the jasmonate family. It plays an important role as a possible airborne signaling molecule mediating intra- and inter-plant communications and modulating plant defense responses, including antioxidant systems. Most assessments of this compound have dealt with post-harvest fruit applications, demonstrating induced plant resistance against the detrimental impacts of storage (chilling injuries and pathogen attacks), enhancing secondary metabolites and antioxidant activity. On the other hand, the interactions between MeJA and other compounds or technological tools for enhancing antioxidant capacity and quality of fruits were also reviewed. The pleiotropic effects of MeJA have raisen numerous as-yet unanswered questions about its mode of action. The aim of this review was endeavored to clarify the role of MeJA on improving pre- and post-harvest fresh fruit quality and health properties. Interestingly, the influence of MeJA on human health will be also discussed.

Methyl jasmonate vapors affect the composition and peroxidation of major fatty acids in common buckwheat seedlings

The effect of methyl jasmonate (MJ) vapors on the composition and peroxidation of major fatty acids in the organs of common buckwheat seedlings was investigated. The composition of fatty acids in the hypocotyl and cotyledons of seedlings changed significantly under exposure to MJ vapors in closed jars. Four-day exposure to MJ led to a significant reduction in the concentrations of stearic, linoleic, and linolenic acids in the hypocotyl, whereas oleic acid levels increased approximately 3.5-fold. A decrease in stearic acid levels and an increase in the content of linolenic acid were noted in cotyledons, whereas oleic acid levels decreased in roots. Seven-day exposure to MJ vapor caused a further reduction in stearic acid content and an increase in oleic acid and linoleic acid levels in the hypocotyl. At the same time, the linoleic acid content of roots and linolenic acid levels in cotyledons were doubled, but a 5-fold reduction in linolenic acid concentrations was observed in roots. Methyl jasmonate intensified fatty acid peroxidation in cotyledons after 4 and 7 days and in roots after 4 days of exposure. Peroxidation was inhibited in the hypocotyl and roots after 7 days. The noted changes in the composition and peroxidation of fatty acids are probably indicative of senescence in buckwheat seedlings under the influence of MJ. Senescence seems to proceed faster in cotyledons than in other organs of buckwheat seedlings.