methyl-jasmonate and benzo-1-2-3-thiadiazole

Proanthocyanidins (PAs) are phenolic compounds present in skins and seeds of wine grapes and have great implications for plant physiology and wine quality. There are several strategies to increase PA concentration, such as application of elicitors methyl jasmonate (MeJ) and benzothiadiazole (BTH), compounds that can stimulate defence responses like phenolic compound biosynthesis in wine grapes, which have been applied mainly at veraison (beginning of ripening). We recently evaluated the application of MeJ and BTH on Vitis vinifera cv. Monastrell grapes during veraison and mid-ripening (3 weeks after veraison). Grapes treated at mid-ripening showed higher anthocyanin concentrations than those at veraison. In this trial, over two seasons, we evaluated whether time of application (veraison or mid-ripening) of MeJ and BTH on 'Monastrell' grapes is a determining factor in the biosynthesis and composition of PAs in grapes and their subsequent release into wines.. Application of elicitors at different ripening times produced significant differences in the PAs of 'Monastrell' grapes, since those treated at mid-ripening recorded a higher PAs concentration in skin and seeds, and then in the wines produced, compared to grapes treated at veraison.. Results suggest that despite different environmental conditions endured in each of the two seasons evaluated, application of elicitors at mid-ripening of Monastrell grapes could be used to harvest grapes with higher PA concentration, increasing the functional value of the wines, without altering their organoleptic quality. © 2022 Society of Chemical Industry.

Topics: Anthocyanins; Fruit; Oxylipins; Phenols; Proanthocyanidins; Vitis; Wine

In recent years, it has been demonstrated that the application of elicitors such as methyl-jasmonate (MeJ) and benzothiadiazole (BTH) to wine grapes can increase their phenolic and aromatic compounds if they are treated at the beginning of ripening (veraison). However, the veraison period is short, and it is not always possible to apply the treatments in a few days. Therefore, it would be of great interest to optimize the moment of elicitor application or extend the treatment period. The aim of this paper was to analyze during two consecutive years (2016-2017) the foliar application of MeJ, BTH, and a combination of both, during two different ripening periods of Monastrell grapes (veraison and mid-ripening), and determine the more appropriate moment to increase the concentration of anthocyanins. To carry out this aim, analysis of anthocyanins by HPLC in grapes and wines was mainly performed. The most suitable period for the application of MeJ, BTH, and MeJ + BTH was at mid-ripening, since the grapes showed a greater accumulation of anthocyanins at harvest. However, the MeJ + BTH treatment applied during veraison also obtained similar results, which would allow extending the application period if necessary. However, the increase in the anthocyanin content of grapes was not reflected in all the wines, which may have been due to reinforcement of the skin cell wall as a result of the application of elicitors. Further analysis is needed to improve the maceration process of the Monastrell grapes and the extraction of the anthocyanins that were increased by the treatments applied in the vineyard.

Topics: Acetates; Anthocyanins; Chromatography, High Pressure Liquid; Color; Cyclopentanes; Discriminant Analysis; Fruit; Oxylipins; Phenols; Plant Growth Regulators; Thiadiazoles; Vitis; Wine

Holm oak trees (Quercus ilex L.) mortality is increasing worryingly in the Mediterranean area in the last years. To a large degree this mortality is caused by the oomycete Phytophthora spp., which is responsible for forest decline and dieback in evergreen oak forest areas of the southwestern Iberian Peninsula. This study is based on the possibility of applying chemical elicitors or filtered oomycete extracts to holm oak somatic embryos (SE) in order to induce epigenetic memory, priming, that may increase tolerance to the pathogen in future infections. To this end, we first examined the effect of priming treatments on SE development and its oxidative stress state, to avoid elicitors that may cause damage to embryogenic tissues. Both, the sterile oomycete extracts and the chemical elicitor methyl jasmonate (MeJA) did not produce any detrimental effect on SE growth and development, unlike the elicitors benzothiadiazole (BTH) and p-aminobenzoic acid (PABA) that reduced the relative weight gain and resulted in necrotic and deformed SE when were applied at high concentrations (25 µM BTH or 50 µM PABA) in accordance with their high malondialdehyde content. No significant differences among elicitation treatments were found in dual culture bioassays, although those SEs elicited with 50 µM MeJA increased H

Topics: 4-Aminobenzoic Acid; Acetates; Cyclopentanes; Forests; Host Microbial Interactions; Hydrogen Peroxide; Malondialdehyde; Oxylipins; Phytophthora; Plant Diseases; Proteins; Quercus; Seeds; Spain; Thiadiazoles

Topics: Acetates; Cold Temperature; Cyclopentanes; Fermentation; Oxylipins; Polyphenols; Thiadiazoles; Vitis; Wine

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.

Topics: Acetates; Cell Wall; Cyclopentanes; Lignin; Multivariate Analysis; Oxylipins; Phenols; Plant Proteins; Seasons; Spectrophotometry; Temperature; Thiadiazoles; Vitis; Wine

This work studied the effect of preharvest application in Monastrell grapes of four different elicitors [methyl jasmonate (MeJ), benzothiadiazole (BTH), chitosan from fungi (CHSf), and chitosan from seafood (CHSs)] on wine polysaccharide and oligosaccharide fractions. The polysaccharide and oligosaccharide fractions were isolated and characterized. Neutral monosaccharides were released after hydrolysis of polysaccharides and quantified by gas chromatography (GC). Sugar composition of oligosaccharides was determined after solvolysis by GC of their per-O-trimethylsilylated methyl glycoside derivatives. MeJ, BTH, CHSf, and particularly CHSs decrease the polysaccharide content in wine. The oligosaccharide concentration was also reduced after both CHS treatments. These results pointed to a lower degradation of the skin cell wall from treated grapes. We suggested that the cause would be a reinforcement of the skin cell wall as a result of the action of these elicitors. In conclusion, the application of any of these four elicitors in the clusters of the vineyard affected the complex carbohydrate composition of elaborated wine.

Topics: Acetates; Chitosan; Cyclopentanes; Dietary Carbohydrates; Fruit; Fungi; Humans; Oligosaccharides; Oxylipins; Polysaccharides; Thiadiazoles; Vitis; Wine

The effect of the application of benzothiadiazole (BTH) and methyl jasmonate (MeJ) at veraison on the phenolic composition of grapes from three varieties (Monastrell, Syrah and Merlot) was studied during the ripening period, using HPLC techniques to measure flavonols, anthocyanins and tannins.. The effects of the treatments differed in the three varieties, and the maximum concentration of phenolic compounds was not always reached at the end of the ripening period but some days before harvest. At the end of ripening both treated Syrah grapes only differed from control grapes in the flavonol concentration, whereas MeJ-treated Merlot grapes presented higher anthocyanin and skin tannin contents than the control and BTH-treated grapes. Only the anthocyanin content was significantly higher in treated Monastrell grapes at the moment of harvest.. The results indicate that the moment of elicitor treatment should be more studied since differences between treated and control grapes were, in general greater several days before harvest in all three varieties. © 2016 Society of Chemical Industry.

Topics: Acetates; Aerosols; Agrochemicals; Anthocyanins; Antioxidants; Chromatography, High Pressure Liquid; Crop Production; Crops, Agricultural; Cyclopentanes; Flavonols; Fruit; Humans; Nutritive Value; Oxylipins; Phenols; Pigments, Biological; Plant Epidermis; Spain; Species Specificity; Spectrometry, Mass, Electrospray Ionization; Spectrophotometry, Ultraviolet; Tannins; Thiadiazoles; Vitis

Amaranthus cruentus (Ac) plants were treated with the synthetic systemic acquired resistance (SAR) inducer benzothiadiazole (BTH), methyl jasmonate (MeJA) and the incompatible pathogen, Pseudomonas syringae pv. syringae (Pss), under greenhouse conditions. The treatments induced a set of marker genes in the absence of pathogen infection: BTH and Pss similarly induced genes coding for pathogenesis-related and antioxidant proteins, whereas MeJA induced the arginase, LOX2 and amarandin 1 genes. BTH and Pss were effective when tested against the Gram negative pathogen Ps pv. tabaci (Pst), which was found to have a compatible interaction with grain amaranth. The resistance response appeared to be salicylic acid-independent. However, resistance against Clavibacter michiganensis subsp. michiganensis (Cmm), a Gram positive tomato pathogen also found to infect Ac, was only conferred by Pss, while BTH increased susceptibility. Conversely, MeJA was ineffective against both pathogens. Induced resistance against Pst correlated with the rapid and sustained stimulation of the above genes, including the AhPAL2 gene, which were expressed both locally and distally. The lack of protection against Cmm provided by BTH, coincided with a generalized down-regulation of defense gene expression and chitinase activity. On the other hand, Pss-treated Ac plants showed augmented expression levels of an anti-microbial peptide gene and, surprisingly, of AhACCO, an ethylene biosynthetic gene associated with susceptibility to Cmm in tomato, its main host. Pss treatment had no effect on productivity, but compromised growth, whereas MeJA reduced yield and harvest index. Conversely, BTH treatments led to smaller plants, but produced significantly increased yields. These results suggest essential differences in the mechanisms employed by biological and chemical agents to induce SAR in Ac against bacterial pathogens having different infection strategies. This may determine the outcome of a particular plant-pathogen interaction, leading to resistance or susceptibility, as in Cmm-challenged Ac plants previously induced with Pss or BTH, respectively.

Topics: Acetates; Amaranthus; Cyclopentanes; Gene Expression Regulation, Plant; Gram-Negative Bacteria; Gram-Positive Bacteria; Oxylipins; Plant Diseases; Pseudomonas syringae; Thiadiazoles

Leaf-to-leaf systemic immune signaling known as systemic acquired resistance is poorly understood in monocotyledonous plants. Here, we characterize systemic immunity in barley (Hordeum vulgare) triggered after primary leaf infection with either Pseudomonas syringae pathovar japonica (Psj) or Xanthomonas translucens pathovar cerealis (Xtc). Both pathogens induced resistance in systemic, uninfected leaves against a subsequent challenge infection with Xtc. In contrast to systemic acquired resistance in Arabidopsis (Arabidopsis thaliana), systemic immunity in barley was not associated with NONEXPRESSOR OF PATHOGENESIS-RELATED GENES1 or the local or systemic accumulation of salicylic acid. Instead, we documented a moderate local but not systemic induction of abscisic acid after infection of leaves with Psj. In contrast to salicylic acid or its functional analog benzothiadiazole, local applications of the jasmonic acid methyl ester or abscisic acid triggered systemic immunity to Xtc. RNA sequencing analysis of local and systemic transcript accumulation revealed unique gene expression changes in response to both Psj and Xtc and a clear separation of local from systemic responses. The systemic response appeared relatively modest, and quantitative reverse transcription-polymerase chain reaction associated systemic immunity with the local and systemic induction of two WRKY and two ETHYLENE RESPONSIVE FACTOR (ERF)-like transcription factors. Systemic immunity against Xtc was further associated with transcriptional changes after a secondary/systemic Xtc challenge infection; these changes were dependent on the primary treatment. Taken together, bacteria-induced systemic immunity in barley may be mediated in part by WRKY and ERF-like transcription factors, possibly facilitating transcriptional reprogramming to potentiate immunity.

Topics: Abscisic Acid; Acetates; Cyclopentanes; Ethylenes; Hordeum; Oxylipins; Plant Diseases; Plant Growth Regulators; Plant Immunity; Plant Leaves; Pseudomonas syringae; Salicylic Acid; Thiadiazoles; Xanthomonas

Benzothiadiazole (BTH) and methyl jasmonate (MeJ) have been described as exogenous elicitors of some plant defense compounds, polyphenols among them. Given that they activate different arrays of biochemical reactions to induce resistance, the objective of this study was to determine whether the joint application of BTH and MeJ to grape clusters affects the level of the main flavonoid compounds in grapes and in the resulting wines. The results are compared with those obtained when abscisic acid (ABA), a plant growth regulator involved in several physiological processes, was sprayed in the same vineyard. The results obtained indicated that, although the application of ABA increased the content of skin anthocyanins and tannins, these positive effects were not reflected in the wines made from these grapes. BTH+MeJ-treated grapes also presented higher anthocyanin and flavonol contents, and in this case, their wines presented better chromatic characteristics that the wine made from control grapes.

Topics: Abscisic Acid; Acetates; Anthocyanins; Cyclopentanes; Flavonoids; Fruit; Oxylipins; Plant Growth Regulators; Thiadiazoles; Vitis; Wine

Benzothiadiazole (BTH) and methyl jasmonate (MeJ) have been described as exogenous elicitors of some plant defense compounds, polyphenols among them. The objective of this study was to determine whether the application of BTH or MeJ to grape clusters at the beginning of the ripening process had any effect on the accumulation of the main flavonoid compounds in grapes (anthocyanins, flavonols, and flavanols) and the technological significance of these treatments in the resulting wines. The results obtained after a 2 year experiment indicated that both treatments increased the anthocyanin, flavonol, and proanthocyanidin content of grapes. The wines obtained from the treated grapes showed higher color intensity and total phenolic content than the wines made from control grapes. The exogenous application of these elicitors, as a complement to fungicide treatments, could be an interesting strategy for vine protection, increasing, at the same time, the phenolic content of the grapes and the resulting wines.

Topics: Acetates; Cyclopentanes; Female; Humans; Male; Oxylipins; Phenols; Taste; Thiadiazoles; Vitis; Wine

Salicylic acid (SA) is a phytohormone required for a full resistance against some pathogens in Arabidopsis, and NPR1 (Non-Expressor of Pathogenesis Related Genes 1) is the only gene with a strong effect on resistance induced by SA which has been described. There can be additional components of SA perception that escape the traditional approach of mutagenesis. An alternative to that approach is searching in the natural variation of Arabidopsis. Different methods of analyzing the variation between ecotypes have been tried and it has been found that measuring the growth of a virulent isolate of Pseudomonas syringae after the exogenous application of SA is the most effective one. Two ecotypes, Edi-0 and Stw-0, have been crossed, and their F2 has been studied. There are two significant quantitative trait loci (QTLs) in this population, and there is one QTL in each one of the existing mapping populations Col-4 × Laer-0 and Laer-0 × No-0. They have different characteristics: while one QTL is only detectable at low concentrations of SA, the other acts after the point of crosstalk with methyl jasmonate signalling. Three of the QTLs have candidates described in SA perception as NPR1, its interactors, and a calmodulin binding protein.

Topics: Acetates; Arabidopsis; Biomass; Chromosome Mapping; Colony Count, Microbial; Cyclopentanes; Ecotype; Genetic Variation; Genotype; Models, Biological; Oxylipins; Phenotype; Plant Diseases; Plant Immunity; Pseudomonas syringae; Quantitative Trait Loci; Salicylic Acid; Signal Transduction; Thiadiazoles

This study was designed to address whether applications of methyl jasmonate (MJ) or Benzothiadiazole (BTH) to cultivated tomato, Lycopersicon esculentum, induced elevated densities of defense-related glandular trichomes on new leaves. Four-leaf tomato plants were sprayed with MJ, BTH, or control solutions, and the density of type VI glandular trichomes on new leaves was subsequently determined at 3, 7, 14, 21, and 28 d. At 7, 14, and 21 d, the density of type VI glandular trichomes on new leaves was significantly higher on MJ-treated plants than on BTH- or control-treated plants. At 7 and 14 d after treatment, the mean density of glandular trichomes on new leaves of MJ-treated plants was ninefold higher than on leaves of control-treated plants. We observed entrapment of immature western flower thrips in trichomes on MJ-treated plants at higher rates than on BTH or control plants. Studies to evaluate potential trade-offs between reductions in pest populations by increased trichome density and possible negative impacts of trichome induction on biological control agents are needed.

Topics: Acetates; Cyclopentanes; Oxylipins; Pest Control, Biological; Plant Growth Regulators; Plant Leaves; Solanum lycopersicum; Thiadiazoles

Salicylic acid is a messenger molecule in the activation of defense responses in plants. In this study, we isolated four cDNA clones representing salicylic acid-induced genes in Chinese cabbage (Brassica rapa subsp. pekinensis) by subtractive hybridization. Of the four clones, the BC5-2 clone encodes a putative glucosyltransferase protein. The BC5-3 clone is highly similar to an Arabidopsis gene encoding a putative metal-binding farnesylated protein. The BC6-1 clone is a chitinase gene with similarities to a rapeseed class IV chitinase. Class IV chitinases have deletions in the chitin-binding and catalytic domains and the BC6-1 chitinase has an additional deletion in the catalytic domain. The BCP8-1 clone is most homologous to an Arabidopsis gene that contains a tandem array of two thiJ-like sequences. These four cabbage genes were barely expressed in healthy leaves, but were strongly induced by salicylic acid and benzothiadiazole. Expression of the three genes represented by the BC5-2, BC5-3 and BCP8-1 clones were also induced by Pseudomonas syringae pv. tomato, a nonhost pathogen that elicits a hypersensitive response in Chinese cabbage. None of these four genes, however, was strongly induced by methyl jasmonate or by ethylene.

Topics: Acetates; Amino Acid Sequence; Brassica rapa; Chitinases; Cyclopentanes; Ethylenes; Gene Expression Regulation, Plant; Genes, Plant; Glycosyltransferases; Molecular Sequence Data; Oxylipins; Pseudomonas; Salicylic Acid; Sequence Alignment; Sequence Homology, Amino Acid; Thiadiazoles

The activation of mitogen-activated protein kinases (MAPKs) has been previously implicated in signal transduction during plant responses to pathogen attack as well as to various environmental stresses. We have isolated from rice a new MAPK cDNA, OsBIMK1 ( O ryza s ativa L. BTH-induced MAPK 1), which encodes a 369-amino-acid protein with moderate to high nucleotide sequence similarity to previously reported plant MAPK genes. OsBIMK1 contains all 11 of the MAPK conserved subdomains and the phosphorylation-activation motif, TEY. We analyzed in detail the expression of OsBIMK1 upon treatment with various chemical and biological inducers of resistance responses in rice and in both incompatible and compatible interactions between rice and Magnaporthe grisea. Expression of OsBIMK1 was activated rapidly upon treatment with benzothiadiazole (BTH) as well as with dichloroisonicotinic acid, probenazole, jasmonic acid and its methyl ester, Pseudomonas syringae pv. syringae, or wounding. Expression of OsBIMK1 was induced rapidly during the first 36 h after inoculation with M. grisea in BTH-treated rice seedlings and in an incompatible interaction between M. grisea and a blast-resistant rice genotype. BTH treatment induced a systemic activation of OsBIMK1 expression. These results suggest that OsBIMK1 plays an important role in rice disease resistance.

Topics: Acetates; Amino Acid Sequence; Base Sequence; Cloning, Molecular; Cyclopentanes; DNA, Complementary; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Plant; Immunity, Innate; Isonicotinic Acids; Magnaporthe; Mitogen-Activated Protein Kinases; Molecular Sequence Data; Oryza; Oxylipins; Phylogeny; Plant Diseases; Pseudomonas; Sequence Analysis, DNA; Sequence Homology, Amino Acid; Signal Transduction; Stress, Mechanical; Thiadiazoles; Thiazoles