Application Of Salicylic Acid Research Articles

Does Exogenous Application of salicylic acid induce salt stress tolerance in potentially high-yielding modern wheat cultivars?

Does Exogenous Application of salicylic acid induce salt stress tolerance in potentially high-yielding modern wheat cultivars?

Enhancing Wheat Growth, Physiology, Yield, and Water Use Efficiency under Deficit Irrigation by Integrating Foliar Application of Salicylic Acid and Nutrients at Critical Growth Stages

Transitioning from full to deficit irrigation (DI) has become a key strategy in arid regions to combat water scarcity and enhance irrigation water use efficiency (IWUE). However, implementing DI requires additional approaches to counter its negative effects on wheat production. One effective approach is the foliar application of salicylic acid (SA), micronutrients (Mic; zinc and manganese), and macronutrients (Mac; nitrogen, phosphorus, and potassium). However, there is a lack of knowledge on the optimal combinations and timing of foliar application for these components to maximize their benefits under arid conditions, which is the primary focus of this study. A two-year field study was conducted to assess the impact of the foliar application of SA alone and in combination with Mic (SA + Mic) or Mic and Mac (SA + Mic + Mac) at various critical growth stages on wheat growth, physiology, productivity, and IWUE under DI conditions. Our result demonstrated that the foliar application of different components, the timing of application, and their interaction had significant effects on all investigated wheat parameters with few exceptions. Applying different components through foliar application at multiple growth stages, such as tillering and heading or tillering, heading, and grain filling, led to significant enhancements in various wheat parameters. The improvements ranged from 7.7% to 23.2% for growth parameters, 8.7% to 24.0% for physiological traits, 1.4% to 21.0% for yield and yield components, and 14.8% to 19.0% for IWUE compared to applying the components only at the tillering stage. Plants treated with different components (SA, Mic, Mac) exhibited enhanced growth, production, and IWUE in wheat compared to untreated plants. The most effective treatment was SA + Mic, followed by SA alone and SA + Mic + Mac. The foliar application of SA, SA + Mic, and SA + Mic + Mac improved growth parameters by 1.2–50.8%, 2.7–54.6%, and 2.5–43.9%, respectively. Yield parameters were also enhanced by 1.3–33.0%, 2.4–37.2%, and 3.0–26.6% while IWUE increased by 28.6%, 33.0%, and 18.5% compared to untreated plants. A heatmap analysis revealed that the foliar application of SA + Mic at multiple growth stages resulted in the highest values for all parameters, followed by SA alone and SA + Mic + Mac applications at multiple growth stages. The lowest values were observed in untreated plants and with the foliar application of different components only at the tillering stage. Thus, this study suggested that the foliar application of SA + Mic at various growth stages can help sustain wheat production in arid regions with limited water resources.

Exogenous application of salicylic acid and low-dose ionizing radiation increases synthesis of bioactive compounds and upregulates phytosterol production of Bitter melon (Momordica charantia)

Exogenous application of salicylic acid and low-dose ionizing radiation increases synthesis of bioactive compounds and upregulates phytosterol production of Bitter melon (Momordica charantia)

Optimizing antidiabetic properties of Galega officinalis extract: Investigating the effects of foliar application of chitosan and salicylic acid

Optimizing antidiabetic properties of <i>Galega officinalis</i> extract: Investigating the effects of foliar application of chitosan and salicylic acid

Exogenous application of salicylic acid improves eradication of apple stem grooving virus and apple chlorotic leaf spot virus in apple

Exogenous application of salicylic acid improves eradication of apple stem grooving virus and apple chlorotic leaf spot virus in apple

The Alteration in Physiological Status, Growth and Essential Oil Profile of French Marigold (Tagetes patula L.) Owing to Seaweed Extract and Salicylic Acid Application

Abstract Purpose Medicinal plants show a relevant importance in human life and health. The use of natural substances in crop management is not only significant for the plant healthy growth and yield, but also for obtaining safe products. The study aimed to examine the effect of seaweed extract (SW) as a natural source of nutrition and salicylic acid (SA) on plant health, physiology and essential oil profile of French marigold (Tagetes patula L.). Methods Three levels of salicylic acid, SA50, SA100 and SA200, (50, 100, and 200 mg L− 1) and three levels of seaweed extract, SW2, SW4 and SW6 (2.0, 4.0, and 6.0 ml L− 1), in comparison with control treatment (tap water) were applied as foliar sprayings. The seven treatments were arranged in randomized complete block design and were replicated thrice in two growing seasons (2020 and 2021). Results Findings pointed out that SA200 increased plant height, branches number plant− 1, stem diameter, leaf area, leaves number plant− 1, plant fresh weight, and plant dry weight by 32.9, 112.2, 59.2, 34.4, 44.3, 33.0 and 56.9% (averages of the two seasons), respectively, compared to the control treatment (tap water). SW6 increased carotenoids content by 34.8 and 46.4% in 2020 and 2021 seasons, respectively. Salicylic acid at the rate of 200 mg L− 1 along seaweed extract at 6 ml L− 1 gave the highest values of total sugars and free amino acids. SA200 alone recorded the maximal value of peroxidase activity surpassing the other treatments. SW6 possessed the greatest essential oil content in both seasons, statistically equaling SA200 in the first season. Huge variations in essential oil profile were recorded under the tested trial treatments. Conclusion It could be concluded that salicylic acid and seaweed extract foliar application unveiled their involvement in diverse physiological and developmental responses; pigment formation, enzyme activities, flower induction, nutrient uptake, essential oil metabolism, and overall plant growth and development. It is recommended to use the highest concentrations of the tested substances (SA at 200 mg L− 1 or SW at 6.0 ml L− 1) for achieving distinctive improvements in physiological responses of French marigold plant.

Elicitation of salicylic acid and methyl jasmonate provides molecular and physiological evidence for potato susceptibility to infection by Erwinia carotovora subsp. carotovora

Among the range of severe plant diseases, bacterial soft rot caused by Erwinia carotovora is a significant threat to crops. This study aimed to examine the varying response patterns of distinct potato cultivars to the influence of E. carotovora. Furthermore, it seeks to highlight the potential role of salicylic acid (SA) and methyl jasmonate (MeJA) in stimulating the antioxidant defence system. We collected eight bacterial isolates from diseased and rotted tubers which were morphologically and physiologically identified as E. carotovora subsp. carotovora. We conducted a greenhouse experiment to analyse the antioxidant responses of three different potato cultivars (Diamont, Kara, and Karros) at various time intervals (2, 4, 6, 8, 12, and 24 h) after bacterial infection (hpi). We assessed the extent of disease damage by applying a foliar spray of 0.9 mM salicylic acid (SA) and 70 μM methyl jasmonate (MeJA). Inoculating with Ecc led to an increase in total phenolic levels, as well as the activities and gene expression of phenylalanine ammonia-lyase (PAL), polyphenol oxidase (PPO) and peroxidase (POX) as time progressed. Additionally, the application of SA and MeJA resulted in a further increase relative to the diseased treatments. The Karros cultivar, unlike the Diamont and Kara cultivars, demonstrated the highest expression levels of PAL, PPO and POX through inoculation, reflecting its higher levels of activity and resistance. Furthermore, the genetic response of potato cultivars to infection at 0 hpi varied depending on their susceptibility. The examination of the rate of PAL activity upregulation following SA or MeJA stimulation clarifies the cultivars' susceptibility over time. In conclusion, the study identified E. carotovora subsp. carotovora as the most virulent isolate causing soft rot disease in potato tubers. It further revealed that the Karros cultivar displayed superior resistance with high activities and gene expression of PAL, PPO and POX, while the cv. Diamont exhibited sensitivity. Additionally, foliar exposure to SA and MeJA induced antioxidant responses, enhancing the potato plants' resistance against Ecc pathogenesis and overall plant defence.

Genome-wide identification of the ICS family genes and its role in resistance to Plasmodiophora brassicae in Brassica napus L

The isochorismate synthase (ICS) proteins are essential regulators of salicylic acid (SA) synthesis, which has been reported to regulate resistance to biotic and abiotic stresses in plants. Clubroot caused by Plasmodiophora brassicae is a common disease that threatens the yield and quality of Oilseed rape (Brassica napus L.). Exogenous application of salicylic acid reduced the incidence of clubroot in oilseed rape. However, the potential importance of the ICS genes family in B. napus and its diploid progenitors has been unclear. Here, we identified 16, 9, and 10 ICS genes in the allotetraploid B. napus, diploid ancestor Brassica rapa and Brassica oleracea, respectively. These ICS genes were classified into three subfamilies (I-III), and member of the same subfamilies showed relatively conserved gene structures, motifs, and protein domains. Furthermore, many hormone-response and stress-related promoter cis-acting elements were observed in the BnaICS genes. Exogenous application of SA delayed the growth of clubroot galls, and the expression of BnaICS genes was significantly different compared to the control groups. Protein-protein interaction analysis identified 58 proteins involved in the regulation of ICS in response to P. brassicae in B. napus. These results provide new clues for understanding the resistance mechanism to P. brassicae.

Morphological and Physiological Responses of Different Cotton Genotypes Primed with Salicylic Acid Under Salinity Conditions

This study was conducted as both petri dishes and pot experiments on four different salt-sensitive cotton genotypes (Laser, May 505, May 455 and Selin) in order to investigate the role of exogenous salicylic acid applications in reducing the effects of salt stress. Six saline treatments; 0, 30, 60, 90, 120 mM NaCl were used. Each group divided into three sub-groups (hydo-primed control, 0.5 mM and 1.0 mM SA) on the basis of seed priming treatments. They were applied in three replications according to the randomized block design. In all genotypes, 90 mM and 120 mM salt stress negatively affected germination and seedling development. In salt stress up to 60 mM, it was recommended to May 505 and Selin genotypes with 0.5 mM salicylic acid pre-application to the seeds.

Short-term salicylic acid application induces the expression of GPPS and NEPS1 in catnip

The catnip plant, Nepeta cataria L., produces bioactive iridoid monoterpenes known as nepetalactones. These monoterpenes follow a noncanonical biosynthetic route starting as isoprene monomers in the methylerythritol (MEP) pathway after condensation via geranyl pyrophosphate synthase (GPPS) and later cyclization through the iridoid pathway via nepetalactol-related short-chain dehydrogenase enzymes (NEPS). Nepetalactones exhibit insect repellant properties against disease-carrying vectors such as mosquitoes, bed bugs and ticks. Chemical elicitors such as salicylic acid have been used to induce biochemical changes in medicinal and aromatic plant species including catnip that can temporarily increase the yield and quality of secondary metabolites. This is the first study to correlate the effects of short-term salicylic acid application on the genes in the nepetalactone biosynthetic pathway. Both 0.5 mM SA and 1.0 mM SA resulted in upregulation of GPPS and NEPS1. However, within the 24-h time course of the study significant changes in nepetalactone yield were not observed. Correlation analysis revealed a significant relationship between the mRNA transcript abundance for GPPS and NEPS1 demonstrating a low positive co-expression strength for the two genes.

Salicylic Acid and Water Stress: Effects on Morphophysiology and Essential Oil Profile of Eryngium foetidum.

The exogenous application of bioregulators, such as salicylic acid (SA), has exhibited promising outcomes in alleviating drought stress. Nevertheless, its impact on culantro (Eryngium foetidum L.) remains unexplored. Thus, the aim of this study was to assess how SA impacts the growth, morphophysiology, and essential oil composition of culantro when subjected to drought. To achieve this, culantro plants were grown under three different watering regimes: well-watered, drought-stressed, and re-watered. Additionally, they were either treated with SA (100 µM) or left untreated, with water serving as the control. SA application did not mitigate the effects of drought in biomass production but increased biomass, leaf number, leaf area, and photosynthetic pigments under well-irrigated and re-watered conditions. After a drought period followed by re-watering, plants recovered membrane integrity independently of SA application. Water stress and the exogenous application of SA also modulated the profile of essential oils. This is the first report about SA and drought affecting growth and essential oil composition in culantro.

The effect of pre-harvest salicylic acid and gibberellic acid applications on-tree storability in ‘Satsuma’ mandarins (Citrus unshiu Marc.)

Objective: Satsuma mandarin (Citrus unshiu Marc.), an important export product for Türkiye, is kept on the tree until the beginning of January. This study aimed to determine the effects of single and co-application of salicylic acid (SA) and gibberellic acid (GA3) on the storability of Satsuma mandarin on trees. &#x0D; Material and Methods: For this purpose, 20 ppm GA₃ two weeks before the color break period, 2 mM SA, and 1.5 ml/L Rezist at the color break period were applied alone and together to Satsuma mandarin fruit. Those without treatment were accepted controls. Various measurements and analyses were made in the samples taken at monthly intervals during storage on the tree. &#x0D; Results: It was harvested in three periods at approximately one-month intervals from the beginning of November. The applications of SA or GA₃ alone or together limited the fruit drop rate during on-tree storage, the increase in the shell thickness, and the decrease in the specific gravity. Applications involving GA₃ delayed the coloration of fruits. The maturity index of the fruits treated with Resist and GA₃ in the first harvest was lower. &#x0D; Conclusion: The results showed that the pre-harvest applications of Satsuma mandarin would have positive contributions to the storage of fruits on the tree until the beginning of January by preventing fruit drop, and delaying the peel and fruit aging.

A Mechanistic Action of Salicylic acid on Metabolic Profiling, Antioxidative Potential, and Growth Pattern of Amaranthus hybridus

This study has been conducted to investigate the effects of salicylic acid application on the growth and biomass of Amaranthus hybridus. The crop was grown in pots during July-August 2023, under natural weather conditions in the botanical garden of Banaras Hindu University, Varanasi. Different doses of SA (0.69 ppm – 13.8 ppm) was sprayed on the shoot of the plants. Compared to the control group, SA application at 0.69 ppm, 1.38 ppm, and 2.76 ppm showed increased growth and yield of the plants. SA applied at 1.38 ppm concentration, particularly, gave maximum increments in the length and biomass of the crop. SA application reduced the formation of oxidative stress markers (H2O2, SOR, MDA) by increasing the activities of antioxidants like SOD, POD, APX, total phenol, and proline. Salicylic acid treatment also increased the nutritive value of the crop by increasing the level of Ca, Mg, Fe, Zn, and protein, while reduced the levels of oxalic acid. The photosynthetic efficiency of the PSII was strengthened better with 1.38 ppm SA application by increasing chlorophyll content, allocation of absorbed light energy to drive the photochemical process, and quenching of the heat energy. The metabolic profiling via UHPLC-Q-TOF-MS/MS revealed increase in the number and proportion of secondary metabolites belonging to phenolic, alkaloids, terpenoid, flavonoids, betalains, and coumarins group by 240%, 127%, 37%, 182%, 83%, and 90% respectively. Hence, 1.38 ppm of SA has been considered as the suitable dose for spraying on Amaranthus hybridus for increased growth and biomass.

Comparative and interactive response of salicylic acid, 24–epibrassinolide or sodium nitroprusside against cadmium stress in Linum usitatissimum

AbstractConcerns regarding the effects of heavy metals (HMs) on agricultural productivity have grown over time. Because HM stress disrupts a number of the plants' physiological-biochemical and metabolic processes, it severely limits production. Phytohormones can effectively improve plants resistance to HM stress. This work was done to examine the comparative effectiveness of salicylic acid (SA), 24–epibrassinolide (EBL) and sodium nitroprusside (SNP) on photosynthetic attributes, growth, &amp; antioxidant enzymes activity in Linum usitatissimum cv. RLC–6 (flax) subjected to cadmium (Cd) stress during vegetative growth stages. Cd considerably decreases the length, biomass, leaf diameter, chlorophyll content, and photosynthetic traits; and further triggered ROS and MDA content in plant. Moreover, exogenous application of SA, EBL and SNP individually and in combination improved the antioxidant enzymatic machinery by increasing the levels of superoxide dismutase (SOD), peroxidase (POX), and catalase (CAT) and decrease the superoxide, hydrogen peroxide, scavenges ROS and MDA accumulation. Furthermore, submission of phytohormones also caused proline to accumulate and the activities of carbonic anhydrase (CA) and nitrate reductase (NR) to be activated which were impaired due to Cd stress. Among the phytohormones, the most effective method for dropping the damaging impacts of Cd and promoting plant growth and development was EBL. However, combined application of all three phytohormones (SA + EBL + SNP) proved to be the best. Thus, it can be concluded that, these augmented activity of antioxidants and proline elicited by application of phytohormones, would have continued to be able to give Linum usitatissimum exposed to Cd stress resistance.

Effect of Spermidine and Salicylic Acid Application on the Morphological and Physiological Characteristics of Quinoa (Chenopodium quinoa) Under Salt Stress Conditions

Effect of Spermidine and Salicylic Acid Application on the Morphological and Physiological Characteristics of Quinoa (Chenopodium quinoa) Under Salt Stress Conditions

Ácido salicílico reduz os efeitos prejudiciais do estresse salino em Tropaeolum majus

ABSTRACT Salt stress hampers the growth and physiology of nasturtium (Tropaeolum majus), due to biochemical, physiological, and anatomical disruptions. The application of salicylic acid stands as an alternative to alleviate the detrimental effects of salt stress, but studies on nasturtium are scarce. Thus, the aim of present study was to assess the effects of foliar application of salicylic acid on nasturtium cultivated under salt stress. The experiment followed a completely randomized design in a 3 x 3 factorial scheme, with 0 (no stress), 50 (moderate salt stress), and 100 (severe salt stress) mM of NaCl, and application of 0, 0.5, and 1 mM of salicylic acid, each with six replications. Growth (plant height, stem diameter, and number of leaves), gas exchange (stomatal conductance, photosynthesis, transpiration, internal CO2 concentration, intrinsic water use efficiency, instantaneous water use efficiency, and intrinsic carboxylation efficiency), as well as chlorophyll indices and chlorophyll a fluorescence were evaluated. Salt stress affected the variables analyzed in this study. The application of salicylic acid had a positive effect on mitigating the effects of severe salt stress, resulting in a significant increase in the number of leaves. The most effective dose was 1 mM, also leading to notable improvements in water use efficiency and photochemical efficiency. However, other combinations of salinity and salicylic acid reduced growth and gas exchange in nasturtium plants.

Ácido salicílico induz aclimatação ao déficit hídrico em genótipos de Phaseolus lunatus

ABSTRACT In Brazil, the lima bean is the second most economically significant legume within the genus Phaseolus. Climate change, particularly water scarcity, threatens the production of this species. The application of salicylic acid has mitigated the adverse effects of stress. This study aimed to assess the impact of salicylic acid on acclimatisation to water restriction in three genotypes of Phaseolus lunatus (‘Cara Larga’, ‘Cearense’, and ‘Orelha de Vó’). A completely randomised design with a triple factorial included three broad bean genotypes, two pre-conditionings with 1.0 mM salicylic acid and without this elicitor (0.0 mM), and three levels of water availability (75, 50, and 25%), totalling 18 treatments with eight replicates. Physiological and biochemical responses were evaluated after 60 days of treatment. The responses varied among the genotypes. ‘Cara Larga’ stood out regarding osmoregulatory and antioxidant parameters compared to the other genotypes. In contrast, ‘Cearense’ showed an increase only in carbohydrates and carotenoids concentrations, while ‘Orelha de Vó’ exhibited more efficient water use and higher levels of proline under greater water restriction, concurrently with a decline in other parameters. Overall, the ‘Cara Larga’ genotype appears to be the most responsive to the modulating effects induced by acid application, especially under a water restriction of 25%. Applying, applying salicylic acid under conditions of low water availability may be a strategy for modulating the synthesis of osmoregulatory and antioxidant responses in P. lunatus.

Enhancing Freeze Tolerance of Field-grown Lettuce with Salicylic Acid, Ascorbic Acid, and Calcium Chloride

With the climate continuing to change, specialty crop growers are particularly at risk for economic loss caused by erratic weather conditions, excess heat and rain, and frost damage. Although tolerant to cold, lettuce (Lactuca sativa) is a major horticultural crop at risk for exposure to freezing temperatures in late fall or early spring in the Midwest. Exogenous applications of salicylic acid, ascorbic acid, and calcium chloride have been shown to improve abiotic stress in plants, particularly with freezing tolerance. This research investigated the effects of the exogenous application of salicylic acid, ascorbic acid, and calcium chloride, in varying concentrations, on field-grown lettuce. The study was conducted at the Iowa State University Horticulture Research Station, Ames, IA, USA. Weekly applications of salicylic acid (0.5 and 1.0 mM), ascorbic acid (0.5 and 1.0 mM), and calcium chloride (10 and 20 mM) were applied until plants were a marketable size. A control treatment (no spray) was also included. Data regarding plant size, yield, leaf area, leaf number, plant dry weight, plant nutrient analysis, and freeze tolerance were collected. Freeze tolerance assessments were conducted through laboratory-simulated freeze events and the evaluation of natural in-field freeze events. Freeze injury was quantified through the electrolyte leakage method. Marketable weights in 2020 and 2021 were statistically similar, except for 1.0 mM salicylic acid in 2020, which showed a significantly lower marketable weight and head diameter. Trends during both years showed that stress protectant applications had the most effective freeze protection at −12 °C in laboratory-simulated freeze events. Calcium chloride at 20 mM had the highest protection at −12 °C, with 13.3% and 24.0% less injury compared with the control in 2020 and 2021, respectively. Salicylic acid 1.0 mM at −12 °C had 4.7% and 23.7% less injury compared with control during these two years, respectively. Ascorbic acid 1.0 mM at −12 °C also showed 6.8% and 9.5% less injury than the control in 2020 and 2021, respectively. Similar trends were observed after in-field freezing events, with 20 mM calcium chloride providing the highest protection against frost in 2020 and 2021. These findings advance the understanding of the capabilities of stress protectants on lettuce as chemical primers after freezing events. This research highlights the benefits of ascorbic acid, salicylic acid, and calcium chloride as stress protectants and encourages future research and further exploration of concentrations, methods of application, and timing of application of products.

Salicylic Acid and Gemma-Aminobutyric Acid Mediated Regulation of Growth, Metabolites, Antioxidant Defense System and Nutrient Uptake in Sunflower (Helianthus annuus L.) Under Arsenic Stress.

Arsenic (As) is a highly toxic and carcinogenic pollutant commonly found in soil and water, posing significant risks to human health and plant growth. The objectives of this study to evaluate morphological, biochemical, and physiological markers, as well as ion homeostasis, to alleviate the toxic effects of As in sunflowers through the exogenous application of salicylic acid (SA), γ-aminobutyric acid (GABA), and their combination. A pot experiment was conducted using two sunflower genotypes, FH-779 and FH-773, subjected to As stress (60mg kg-1) to evaluate the effects of SA at 100mg L-1, GABA at 200mg L-1, and their combination on growth and related physiological and biochemical attributes under As stress. The study revealed that As toxicity had a detrimental effect on various growth parameters, chlorophyll pigments, relative water content, total proteins, and nutrient uptake in sunflower plants. It also led to increased oxidative stress, as indicated by higher levels of malondialdehyde (MDA) and hydrogen peroxide (H2O2), along with As accumulation in the roots and leaves. However, the application of SA and GABA protected against As-induced damage by enhancing the enzymatic antioxidant defense system. This was achieved through the activation of superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) activities, as well as an increase in osmolytes. They also improved nutrient acquisition and plant growth under As toxicity. We investigated the regulatory roles of SA and GABA in mitigating arsenic-induced phytotoxic effects on sunflower. Our results revealed a significant interaction between SA and GABA in regulating growth, photosynthesis, metabolites, antioxidant defense systems, and nutrient uptake in sunflower under As stress. These findings provide valuable insights into plant defense mechanisms and strategies to enhance stress tolerance in contaminated environments. In the future, SA and GABA could be valuable tools for managing stress in other important crops facing abiotic stress conditions.

Effects of exogenous application of MeJA and SA on the physiological and molecular response of 'Dusa' avocado to Rosellinia necatrix.

Methyl jasmonate (MeJA) and salicylic acid (SA) are important in mediating plant responses to abiotic and biotic stresses and can act as elicitors by triggering plant defense responses similar to those induced by pathogens and may even provide long-term protection against them. Thus, exogenous application of MeJA and SA could protect susceptible avocado plants against white root rot (WRR) disease caused by the necrotrophic fungus Rosellinia necatrix, one of the main diseases affecting avocado orchards. This work evaluates the effects of MeJA or SA on the physiological and molecular response of susceptible 'Dusa' avocado rootstock, and their ability to provide some protection against WRR. MeJA and SA application in avocado increased photoprotective mechanisms (NPQ) and upregulated the glutathione S-transferase, suggesting the triggering of mechanisms closely related to oxidative stress relief and reactive oxygen species (ROS) scavenging. In contrast to SA, MeJA effects were more pronounced at the morpho-anatomical level, including functional traits such as high leaf mass area (LMA), high stomatal density, high root/shoot ratio, closely related to strategies to cope with water scarcity and WRR disease. Moreover, MeJA upregulated a greater number of defense-related genes than SA, including a glu protease inhibitor, a key gene in avocado defense against R. necatrix. The overall effects of MeJA increased 'Dusa' avocado tolerance to R. necatrix by inducing a primed state that delayed WRR disease symptoms. These findings point towards the use of MeJA application as an environmentally friendly strategy to mitigate the impact of this disease on susceptible avocado orchards.