Combined Application Of Salicylic Acid Research Articles

Boosting Drought Resistance in Pepper (Capsicum annuum L.) with the Aid of Arbuscular Mycorrhizal Fungi and Key Phytohormones

Drought is a primary abiotic stressor that markedly impairs pepper growth and quality. This study aimed to investigate the effects of foliar applications of phytohormones, including salicylic acid (SA), jasmonic acid (JA), and root application of arbuscular mycorrhizal fungi (AMF), on severe and moderate drought stress of 38-day-old ‘Anemon F1’ pepper plants. The results showed that drought stress led to a considerable decrease in plant growth parameters, nutrient uptake, leaf water content, and chlorophyll content, and it increased leaf temperature, phenolic and flavonoid contents, and antioxidant enzyme activity. Nevertheless, the combined application of AMF with SA and JA demonstrated substantial synergistic effects, resulting in a notable improvement in the ability to alleviate the detrimental impacts of drought stress. Furthermore, the combined application of AMF and phytohormones exhibited a stronger effect on drought stress compared with the individual application of AMF or phytohormones alone. The application of AMF+SA and AMF+JA not only improves the availability of essential nutrients but also leads to an increase in fresh shoot weight, relative water content, leaf area, and chlorophyll and antioxidant capacity. Consequently, the combined application of SA and JA with mycorrhiza emerged as a promising treatment for enhancing pepper growth under drought-stress conditions. The positive results observed in pepper cultivation through the combined use of phytohormones and mycorrhizae in regions with limited water availability emphasize the importance of investigating the effectiveness of similar approaches in other agricultural crops.

Phytohormones and arbuscular mycorrhizal Rhizoglomus intraradices together modulate defense mechanisms in mungbean to reduce Ni toxicity

The roles of Salicylic acid (SA), Nitric Oxide (NO) and Rhizoglomus intraradices in imparting tolerance to Vigna radiata (mungbean) in Nickel (Ni) contaminated soil have been studied individually but not cumulatively. In this study, pot experiments were conducted to compare the individual and synergistic role of phytohormones, with/without R. intraradices in modulating soil properties and curbing the generation of reactive carbonyl species, reactive oxygen species in mungbean plants subjected to Ni (0, 150 mgkg−1) stress. Ni had a negative correlation with growth and productivity potential of plants. Application of phytohormones and arbuscular mycorrhiza (AM) improved the yielding potential by successfully boosting the functioning of enzymes involved in glyoxalase pathway and antioxidant defense system. AM improved the functional efficiency of plants by modulating soil properties and various defense mechanisms to a maximum extent followed by SA and least by NO. Moreover, exogenous application of phytohormones to AM inoculated plants increased the colonisation capacity of fungal partner significantly, which in turn enhanced the synthesis of glomalin and improved the activity of soil enzymes responsible for nutrient cycling. However, combined application of SA with AM functioned in a more synergistic manner than the combined application of NO with AM. Interestingly, the cumulative treatment of the two phytohormones along with R. intraradices was the most efficient in re-establishing mungbean plants under Ni-stress. The study suggested the use of this cost-effective ameliorative strategy involving the combined use of phytohormones with AM to improve the agricultural outputs of mungbean cultivation even under Ni-stressed environments. The study recommends combined applications of phytohormones with AM to impart Ni tolerance to mungbean plants. However, field studies are suggested to be carried out for the authentication of present result findings.

A New Approach for Extending Shelf-Life of Pomegranate Arils with Combined Application of Salicylic Acid and Methyl Jasmonate

The consumption of fresh-cut pomegranate fruits (arils) has risen recently due to their bioactive compounds and benefits for consumers. However, pomegranate arils have a limited shelf-life and vastly lose their valuable compounds. Therefore, in this study, we investigated the effects of exogenous postharvest treatment with salicylic acid (SA), methyl Jasmonate (MeJA), and their combination on the shelf-life and chemical composition of pomegranate arils under refrigerated storage (5 °C and 90 ± 2% relative humidity) for 15 days. The results indicated that individual or combined application of SA at 2 mM + MeJA at 0.5 mM decreased weight loss, respiration rate, hue angle (h°), and soluble solids content (SSC) compared to the control. All treatments maintained vitamin C, titratable acidity (TA), anthocyanin content, flavonoids, phenolic compounds, and antioxidant capacity under cold conditions compared to the control. The combined application was more effective than the individual application. In conclusion, SA + MeJA application could be applied during the preparation of fresh-cut pomegranate for maintaining quality and bioactive compounds.

Kadmiyum Bulaştırılmış Yetiştirme Ortamda Mısır Fidesinin (Zea mays L.) Gelişimine, Kadmiyum İçeriğine ve Alımına Mikoriza ve Salisilik Asit Uygulamalarının Etkisi

Cadmium (Cd) pollution is an important problem today. In this study, the effects of mycorrhiza (M) and salicylic acid (SA) applications on plant height, fresh weight, dry weight, number of leaves, and Cd content and uptake of maize (Zea mays L.) seedlings grown in Cd treated environments were determined. For this purpose, 3 kg pots with and without mycorrhizae were used with two doses of salicylic acid (SA1: 1.0 mM and SA2: 2.0 mM). The study was carried out in three replications. As a result of the measurements, mycorrhiza and Salicylic acid applications significantly increased plant height, fresh and dry weight of corn seedlings. On the other hand, mycorrhiza and Salicylic acid applications decreased Cd content and uptake. The lowest plant height was 26.63 cm, the number of leaves was 5.6, the fresh weight was 3.74 g and the dry weight was 1.63 g in the control group, which was not treated with mycorrhiza and SA. The highest plant height was 56.17 cm, the number of leaves was 7.50, and the fresh weight was 21.46 g, with 2.0 mM SA application without mycorrhiza treatment. The highest dry weight was determined with 5.70 g in mycorrhiza and 2.0 mM SA application. While the highest Cd content of corn seedlings was 3.37 mg kg-1 and its uptake was 5.95 mg kg-1 in the control application, the lowest Cd content was 0.307 mg kg-1 and uptake were 1.48 mg kg-1 with mycorrhiza with 2.0 mM SA and 1.0 mM SA. detected in applications. When the results of our study were examined, mycorrhiza and SA applications had positive effects on corn seedlings grown in Cd-contaminated environments. The combined application of salicylic acid and mycorrhiza will contribute significantly to yield and nutrient content in agricultural production against heavy metal pollution.

Влияние совместной обработки эндофитным штаммом бактерий Bacillus thuringiensis B-5351 и салициловой кислотой на устойчивость растений картофеля к Phytophthora infestans (Mont.) de Bary

Влияние совместной обработки эндофитным штаммом бактерий Bacillus thuringiensis B-5351 и салициловой кислотой на устойчивость растений картофеля к Phytophthora infestans (Mont.) de Bary

Salicylic Acid and Calcium Signaling Induce Physiological and Phytochemical Changes to Improve Salinity Tolerance in Red Amaranth (Amaranthus tricolor L.)

Amaranth (Amaranthus tricolor L.) is a plant that is rich in vitamins, minerals, and phytochemicals. It is grown as a leafy vegetable in marginal environments, but high salinity levels in the soil can have a detrimental effect on its growth. These deleterious effects of salinity can be alleviated by exogenously applying signaling compounds such as salicylic acid (SA) and calcium (Ca), which can improve plant adaptation to stressful conditions. The present study evaluated the physiological and phytochemical responses of red amaranth (Amaranthus tricolor L.) to foliar-applied salicylic acid (SA; 0.005 mM) and calcium (CaSO4??2H2O; Ca, 2.5 mM) either alone or in combination (SA + Ca) under conditions of 100 mM NaCl salinity. The set-up was placed under greenhouse condition from May to October 2017. Treatments without salinity and applied with SA or Ca were used as controls for comparison. Salinity stress reduced the growth and biomass, total chlorophyll contents, and increased electrolyte leakage with Na+ and Cl??? accumulation in shoot and roots. Nonetheless, exogenous applied SA and/or Ca2+ reduced the adverse effects of salinity by modulating growth, Na+ exclusion from roots, and increased total phenolics, flavonoids, and antioxidant activity in red amaranth. The combined application of salicylic acid and calcium can be a better strategy for improving the salinity tolerance of amaranth under salt-stressed conditions.

Mitigation of salinity in chickpea by Plant Growth Promoting Rhizobacteria and salicylic acid

For growth or development of pulses, biotic and abiotic environmental factors are more conspicuous under stress conditions. For the survival against abiotic stresses, salicylic acid (SA) is reported a universal remedy. At the Soil Bacteriology Section, Ayub Agricultural Research Institute, Faisalabad, a pot study was conducted to monitor the role of Plant Growth Promoting Rhizobacteria (PGPR) and Salicylic acid in chickpea under salt stress. Eight treatments including control PGPR inoculation and Salicylic acid with their different combination were used. Results revealed that positive response of PGPR on productivity of chickpea but more enunciated response about grain yield was observed with the combined application of SA and PGPR compared to control. Growth parameters i.e root length, root mass, number of nodules and shoot mass were highly affected where SA was applied along with PGPR. From the study, it is proposed that under salt stress the combination of SA + PGPR can be a suitable practice for more production of chickpean Pakistan.

Changes in some antioxidant enzymes and physiological indices of purple coneflower (Echinacea purpurea L.) in response to water deficit and foliar application of salicylic acid and spermine under field condition

Echinacea purpurea is an important industrial and ornamental plant that its quality and physiological parameters may be negatively affected by drought, however, negative effects of drought could be reversed by application of plant growth regulators such as salicylic acid (SA) and spermine (SPM). Therefore, this experiment was conducted to investigate the effects of irrigation regimes (irrigation after 20, 40 and 60% soil water depletion) and, SA and SPM treatments (no spray, 75 mg L−1 SA, 150 mg L−1 SA, 70 mg L−1 SPM, 75 mg L−1 SA + 70 mg L−1 SPM and 150 mg L−1 SA + 70 mg L−1 SPM) on the activities of antioxidant enzymes catalase (CAT), peroxidase (POX), ascorbate peroxidase (APX) and superoxide dismutase (SOD), shoot dry mass (SDM), chlorophyll (Chl), carotenoid (Caro), proline (Pro), phenol, flavonoid and Malondialdehyde (MDA) in purple coneflower (Echinacea purpurea L.). Water deficit increased the activities of enzymes, and the contents of carotenoids, proline, MDA, phenol and flavonoid while it decreased chlorophyll content and shoot dry mass. Among tested enzymes, CAT showed the highest increase in response to water deficit. SA and SPM application increased antioxidant enzymes activities, shoot dry mass and the contents of chlorophyll, carotenoid, proline and flavonoid (only by SA application), but decreased phenol and MDA contents. SOD was the most responsive enzyme to SA and SPM. However, the magnitude of SA and SPM effects was dependent on the level of soil available water. The positive effects of SA were greater than those of SPM. The superiority of SA over SPM was more pronounced at higher level of water deficit. The effects of SA application were greater at 150 than at 75 mg L−1. The highest plant biomass was produced under combined application of SA and SPM. These results indicated that SA and SPM improve purple coneflower growth under water deficit by stimulating antioxidant defense system, alleviating lipid peroxidation and increasing osmotic adjustment. The results also suggest that growers can use SA and SPM to increase productivity of purple coneflower under drought stress.

Effect of Salicylic Acid and Potassium Application on Yield and Grain Nutritional Quality of Wheat under Drought Stress Condition

Drought stress severely reduces wheat productivity and affects grain quality. In this study the effects of combined application of salicylic acid (SA) and potassium (K) on yield and grain quality of wheat under drought stress condition was investigated. Winter wheat cultivar Minaminokaori was grown in pots in a greenhouse, and subjected to 3 levels of K (50, 100 and 200 kg ha−1) fertilizer applications. The plants were foliar sprayed with SA (0.7 mM) at heading stage, and then imposed to the drought stress until grain maturity. Drought stress decreased grain yield by 41.1%, starch content by 10.2% and water-soluble pentosan content by 3.5% in comparison to well-irrigated control. However, grain crude protein content, total pentosan content and phytate phosphorus content were increased by 33.0%, 17.9%, and 13.4% respectively. Under the same drought condition, the application of combined SA and high K levels has increased grain yield (13.3%), starch (12.2%) and water-soluble pentosan content (20.3%) compared to SA-untreated with low level of K fertilizer. In addition, SA application decreased the percentage of phytate phosphorus to total phosphorus under drought stress. These results suggested that combined treatment of SA foliar application and a higher doses of K fertilizer can partially improve wheat productivity, grain nutritional quality, particularly water-soluble pentosan that influences the bread-making quality, without increasing the anti-nutrient component phytate under drought stress condition.

Determination of the role of salicylic acid and Benzothiadiazole on physico-chemical alterations caused by Cucumber mosaic virus in tomato

Shoe-string disease caused by Cucumber mosaic virus (CMV) is one of the major threats to tomato production worldwide. The alteration in some biochemical parameters in leaves of the susceptible tomato genotype (Nagina) associated with CMV infection and the effect of exogenous application of salicylic acid (SA) and benzothiadiazole (BTH) were studied in this paper. Results showed that exogenous treatment with SA and BTH not only led to plants which gave significantly more yield than diseased controls (DC), but also delayed symptom expression and reduced disease severity. Analysis of biochemical parameters indicated that exogenous application of elicitors and viral infection, significantly affected the activity of peroxidase (POD), superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX). Compared to the DC plants, minimum disease severity and maximum number of fruit were recorded after a single dose of SA + BTH. Maximum plant height was recorded after weekly application of SA and maximum fruit yield per plant was gained with single dose of SA. Moreover, the activity of POD was significantly elicited many-fold after weekly application of SA + BTH, while higher amount of SOD was recorded with single dose of SA. The activity of CAT was also significantly accelerated after weekly application of SA + BTH while increased level of APX was noticed with single dose of BTH. In conclusion, the combined application of SA and BTH played an important role in induction of defense mechanism against CMV infection and can be useful in tomato disease management programs.

Modulation of salt stress effects on the growth, physio-chemical attributes and yields of Phaseolus vulgaris L. plants by the combined application of salicylic acid and Moringa oleifera leaf extract

Two field experiments were aimed to study the effects of salicylic acid (SA; 1mM) and Moringa oleifera leaf extract (MLE; 1 extract: 30 tap water), used singly or in combination on the growth, physio-chemical attributes and yields of common bean (Phaseolus vulgaris L.) plants grown on a saline soil (EC=6.23–6.28dSm−1). The SA or MLE application, used as seed soaking or foliar spray, improved growth characteristics (i.e., shoot length, number and area of leaves per plant, and plant dry weight) and physio-chemical attributes (i.e., RWC% and MSI%, concentrations of total chlorophylls, total carotenoids, total soluble sugars, free proline and ascorbic acid, contents of N, P, K and Ca, and ratios of K/Na and Ca/Na) in bean plants. In addition, green pod and dry seed yields were improved when compared with the controls (tap water seed soaking or foliar spray). Combined treatments of SA and MLE (i.e., seed soaking in SA+ foliar spray with SA, seed soaking in SA+foliar spray with MLE, seed soaking in MLE+foliar spray with SA, and seed soaking in MLE+foliar spray with MLE) significantly increased all abovementioned parameters compared to the control (seed soaking in tap water+foliar spray with tap water). In contrast, there were significant reductions in leaf EL% and Na% under these combined treatments. The combined seed soaking in SA+foliar spray with MLE treatment was found to be highly effective at improving the growth and yields of bean plants by alleviating the inhibitory effects of soil salinity stress.

外源SA和NO对NaCl胁迫下番茄幼苗生长、光合及离子分布的影响

以番茄（<em>Lycopersicon esculentum</em> Mill.）品种‘秦丰保冠’为试材，采用营养液培养法，研究单独和复配施用外源水杨酸（SA）、一氧化氮（NO）供体硝普钠（SNP）对100mmol/L NaCl胁迫下番茄幼苗生长、光合及离子分布的影响。结果表明：（1）单独和复配外施SA、SNP均能有效抑制NaCl胁迫下番茄幼苗叶片光合色素（Chla、Chlb、Chla+b和Car）含量、Chla/b值、净光合速率（<em>P</em>_n）、蒸腾速率（<em>T</em>_r）、气孔导度（<em>G</em>_s）、瞬时水分利用效率（WUE_t）、表观光能利用效率（LUE_app）和表观CO₂利用效率（CUE_app）的下降及Car/Chla+b值和胞间CO₂浓度（<em>C</em>_i）的升高，并以SA 和SNP复配处理效果最明显。（2）NaCl胁迫下，外源SA、SNP单独和复配处理的番茄幼苗各器官（叶、茎和根）中Cl^-、Na⁺含量和Na⁺/K⁺、Na⁺/Ca²⁺、Na⁺/Mg²⁺值显著降低，而K⁺、Ca²⁺和Mg²⁺的含量却不同程度提高，其中以SA 和SNP复配处理效果最好。（3）单独和复配外施SA、SNP均能有效减轻NaCl胁迫对番茄幼苗生长的抑制作用，并促进各器官生物量的积累和壮苗的形成，且以SA 和SNP复配处理效果更佳。研究表明，复配外施SA和SNP在诱导番茄幼苗提高抗（耐）盐能力方面具有协同增效作用。

Induction of Resistance in Tomato Plants Against Fusarium Oxysporum F. SP. Lycopersici Mediated Through Salicylic Acid and Trichoderma Harzianum

The effect of a soil application of salicylic acid (SA) and a biocontrol agent, Trichoderma harzianum (TH) on the induction of phenolic accumulation content and defense enzymes in tomato plants infected with Fusarium oxysporum f. sp. lycopersici (F. oxys- porum) was investigated. The phenolic content was recorded to be higher in all the treatments viz. F. oxysporum, F. oxysporum + TH, F. oxysporum + SA and F. oxysporum + TH + SA than that of the healthy plants and reached its maximum level in the plants treated with F. oxysporum + TH + SA. Tomato plants treated with different concentrations of SA (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 mM) showed significant increases in the activities of both peroxidase and polyphenol oxidase where a prominent enhancement was observed at a 1.5 mM concentration of SA. F. oxysporum infection resulted in the induction of both of the enzyme activities but at a lower level. The activities of both peroxidase and polyphenol oxidase reached their maximum on the 28th day, when the plants were treated with F. oxysporum and SA (1.5 mM). The combined application of SA (1.5 mM) and TH in Fusarium infected tomato plants, also enhanced the activities of both of the enzymes.