Application Of SA Research Articles

Salicylic acid and thiourea mitigate the salinity and drought stress on physiological traits governing yield in pearl millet- wheat.

Plant growth is often affected with hampered physiological and cellular functioning due to salinity and drought stress. To assess the effectiveness of plant bioregulators (PBRs) in mitigating abiotic stresses, a double spilt plot field study was conducted with three replications at ICAR-CSSRI, research farm, Nain, Panipat. The study comprised of three deficit irrigation regimes viz., 100, 80 and 60% of crop evapo-transpiration (ETc) (I1, I2 and I3), four levels of irrigation water salinity i.e. 2, 4, 8, 12 dS m−1 (S0, S1, S2 and S3) and two PBRs salicylic acid (SA; G1) and thiourea (TU; G2). Irrigations, as per regimes and salinity, were applied at identified critical stages of wheat and if needed in pearl millet. PBRs were applied as seed priming and foliar sprays at two sensitive stages of respective crops. The trend of plant height, and physiological and biochemical traits was similar under different treatments at both stages, but differed significantly only at reproductive stage. Water deficit caused significant reduction in pearl millet (5.1%) and wheat (6.7%) grain yields. The reduction in grain yield under 8 and 12 dS m−1 was 12.90 and 22.43% in pearl millet and 7.68 and 32.93% in wheat, respectively compared to 2 dS m−1. Application of either SA (G1) or TU (G2) significantly enhanced plant height and grain yield, but magnitude of the increment was higher with SA in pearl millet and with TU in wheat. Application of SA and TU increased grain yield by 14.42 and 12.98 in pearl millet, and 12.90 and 17.36% in wheat, respectively. The plant height, RWC, TC, MI, LP, proline, Fv/Fm and Na/K ratio significantly reduced by salinity stress in pearl millet and both water and salinity stress in wheat. Application of both PBRs proved beneficial to mitigate adverse effect of water deficit and salt stress by significantly improving physiological traits, biochemical traits and ultimately grain yield in both crops.

Exogenously applied growth promoters modulate the antioxidant enzyme system to improve the cotton productivity under water stress conditions

Great climatic inconsistency and increased frequent occurrences of severe conditions results in plants being exposed to water stress at various growth stages, thus adversely affecting the productivity. This investigation was planned to minimize the water stress induced-losses to cotton plants with the exogenous application of growth promoters i.e. distilled water, salicylic acid (0.5 mM), jasmonic acid (50 μM) and moringa leaf extract (MLE30) including control (un sprayed). Cotton plants were exposed to water stress with the application of irrigation water at 10 (well watered) and 30 day intervals (severe water stress). Results indicated that water stress severely reduced the cotton productivity. It was observed that exogenous application of salicylic acid and moringa leaf extract improved the productivity both under well watered and water stress conditions as compared to other treatments. However, exogenous application of salicylic acid had greater influence on the studied parameters than MLE, although the insignificant differences were documented in most of the traits. Exogenous application of salicylic acid reduced the cell injury percentage, improved the cell membrane thermostability and produced significantly higher content of leaf protein, superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) that modulated the negative influence of water stress on yield contributing attributes and produced maximum seed cotton yield. These results indicate that exogenous application of SA and MLE helped the cotton plants to become more tolerant to water stress-induced losses by adjusting the membrane characteristics and improving their antioxidant defense mechanism.

Salicylic acid regulates photosynthetic electron transfer and stomatal conductance of mung bean (Vigna radiata L.) under salinity stress

Abstract The role of salicylic acid (0, 1 and 1.5 mM) on photosynthetic electron transfer chain of mung-bean plants grown under salt stress (0, 3, 6 and 9 dS/m2) was studied using chlorophyll a fluorescence (ChlF) measurements. Results indicated that accumulation of K+ content decreased but, Na+ content increased with increasing salt stress. SA-treated plants had more K+ and less Na+ content compared with the non-SA treated plants. Application of SA, especially with 1 mM, increased the I–P step of the OJIP transient curve of fluorescence. Salt stress decreased gs, CCI, FV, FM, SM and PIabs in plants. However, the time taken to reach FM (TFM) increased with increasing salt stress. Application of different concentrations of SA significantly improved gs, CCI, FV, SM, and PIabs of plants. Photosynthetic efficiency of plants improved as a result of SA application via decreasing Fo and increasing FV/FM, FV/Fo, SM/TFM and Area under both saline and non-saline conditions. Accumulation of Na+ had negative, but K+ had a positive correlation with gs, CCI and most of the chlorophyll a fluorescence parameters (except, Fo and TFM). A positive correlation was found between gS and CCI with PIabs. This research indicated that low gs under saline condition seems to cause losses in PSII efficiency, but the application of SA with 1 mM concentration is the best treatment for the alleviation of salt stress injuries on PSII activity of mung bean plants.

Is gastrointestinal motility related to alkaloids of Charred Semen Arecae?

Ethnopharmacological relevanceSemen Arecae (SA) is one of the most commonly used Traditional Chinese Medicine. Charred Semen Arecae (CSA) is the processed product of SA. Alkaloids are considered as pharmacological mechanisms of SA and CSA on gastrointestinal motility. Recent studies have shown alkaloids decreased quickly after procession. However, the promoting on gastrointestinal motility were not decreased.Is gastrointestinal motility related to alkaloids of CSA? This study explored the effects of SA, CSA, Semen Arecae-Removal (SA-R), and Charred Semen Arecae-Removal (CSA-R) on gastrointestinal motility, Gastric Inhibitory Polypeptide (GIP), Glucagon Like Peptide-1 (GLP-1), gastric juice and bile in rats. Material and methodsRats were randomly divided into six groups, including the Control group, SA group, CSA group, SA-R group, CSA-R group, and Positive drug group (Mosapride). Alkaloids of samples were knocked out by using the “target constituent removal” strategy. Gastric residue and intestinal propulsion rate were evaluated in rats. Serum levels of GIP and GLP-1 were measured by Enzyme-Linked Immunosorbent Assay (ELISA). Gastric juice and bile were examined, respectively. ResultsCSA-R and SA-R have been investigated by the Preparative Thin-layer Chromatography (PTLC) method. Intestinal propulsion and gastric residue assessments confirmed the effectiveness of CSA and CSA-R. CSA-R was higher than SA-R in the GLP-1, pepsin activity, the secretion of bile, Bilirubin (BIL), and Cholesterol (CHO). The statistical comparison demonstrated that there is no difference between the CSA group and CSA-R group. ConclusionsAfter processing, the promoting gastrointestinal motility might be not related to alkaloids. Maillard reaction could be produced to promote the secretion of GLP-1, bile, and CHO for gastrointestinal motility. Our findings provide a pharmacological reference for the clinical application of SA and CSA in the treatment of digestive diseases.

Role of salicylic acid in regulating ethylene and physiological characteristics for alleviating salinity stress on germination, growth and yield of sweet pepper.

BackgroundDuring a preliminary study, effects of 0, 20, 40, and 60 mM NaCl salinity were assessed on germination rate in relation to electrolyte leakage (EL) in sweet pepper. Results explored significant rises in ethylene evolution from seeds having more EL. It was, therefore, hypothesized that excessive ethylene biosynthesis in plants due to salinity stress might be a root cause of low crop productivity. As salicylic acid is one of the potent ethylene inhibitors, thus SA was used to combat effects of ethylene produced under salinity stress of 60 mM NaCl on different physiological and morphological characteristics of sweet pepper.MethodologyThe effect of 0.05, 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6 mM SA was evaluated on seed germination, growth and yield of sweet pepper cv. Yolo wonder at salinity stress on 60 mM NaCl. Seeds were primed with SA concentrations and incubated till 312 h in an incubator to study germination. Same SA concentrations were sprayed on foliage of plants grown in saline soil (60 mM NaCl).ResultsSeeds primed by 0.2 to 0.3 mM SA improved germination rate by 33% due to suppression of ethylene from 3.19 (control) to 2.23–2.70 mg plate−1. Electrolyte leakage reduced to 20.8–21.3% in seeds treated by 0.2–0.3 mM SA compared to 39.9% in untreated seeds. Results also explored that seed priming by 0.3 mM improved TSS, SOD and chlorophyll contents from 13.7 to 15.0 mg g−1 FW, 4.64 to 5.38 activity h−1 100 mg−1 and 89 to 102 ug g−1 compared to untreated seeds, respectively. Results also explore that SA up to 0.2 mM SA applied on plant foliage improved LAI (5–13%), photosynthesis (4–27%), WUE (11–57%), dry weight (5–20%), SOD activity (4–20%) and finally fruit yield (4–20%) compared to untreated plants by ameliorating effect of 60 mM NaCl. Foliar application of SA also caused significant increase in nutrient use efficiency due to significant variations in POD and SOD activities.ConclusionSalicylic acid suppressed ethylene evolution from germinating seeds up to 30% under stress of 60 mM NaCl due to elevated levels of TSS and SOD activity. Foliar application of SA upgraded SOD by lowering POD activity to improve NUE particularly K use efficiency at salinity stress of 60 mM NaCl. Application of 0.2 and 0.3 mM SA emerged as the most effective concentrations of SA for mitigating 60 mM NaCl stress on different physiological and morphological characteristics of sweet pepper.

Genotypic‐specific response to exogenous applied salicylic acid in tall fescue under different irrigation conditions

AbstractSalicylic acid (SA) is one of the endogenous plant growth regulators that play an important role in the regulation of plant growth and development in response to water deficit. Genotypic‐specific response to exogenous applied SA in terms of physiological, enzymatic activity, and yield traits is poorly understood in tall fescue [Lolium arundinaceum (Schreb.) Wimm. syn. Festuca arundinacea Schreb.]. Twenty genotypes of tall fescue (selected from a broad germplasm) were assessed at field condition for morphological and physiological characteristics during 2016 and 2017 under three irrigation levels (normal, mild, and intense drought stress) in the presence of two SA concentrations (0 and 1 mM). Mild and intense drought stress conditions led to depression in photosynthetic pigments including chlorophyll a and b and total chlorophyll contents, plant height, crown diameter, and forage yield, despite increases in proline content, carotenoids, catalase, peroxidase, and ascorbate peroxidase activities. Application of SA decreased the adverse effects of drought stress by elevation of photosynthetic pigments and nonenzyme and enzymatic antioxidant activities and could enhance forage yield and drought tolerance in tall fescue genotypes. High genetic variation was observed among the genotypes in their response to the application of SA under drought stress conditions, and genotypes 3L and 1E were recognized as drought tolerant and stable genotypes for future breeding programs.

Effect of biotic and abiotic elicitors on isoflavone biosynthesis during seed development and in suspension cultures of soybean (Glycine max L.).

The present investigation aimed to look at the effects of biotic and abiotic elicitors during Soybean seed development and cell suspension culture in isoflavones accumulation. The expression levels of four major genes viz., CHS7, CHS8, IFS2, and IFS1 involved on isoflavones biosynthesis during seed developmental stages from R5L-R7 was seen in both MAUS-2 and JS-335 Soybean varieties. The R7 stage showed 1.24-fold upregulation of IFS1transcript level and considered as the control for Soybean seed development. Both varieties during R6-R8 stages responded differently to the foliar application of 10µM SA, 10µMMJ and 0.1% Aspergillus niger. The IFS2 transcripts were upregulated by SA at the R7 stage with 5.21- and 4.68-fold in JS-335 and MAUS-2, respectively. IFS1 expression was significantly increased by A. niger treatment at R7 stage with 3.98- and 3.21-fold in MAUS-2 and JS-335, respectively. The expression of CHS7 and CHS8 by 10μM SA at R7 level revealed maximum up-regulation of 0.51- and 1.01-fold in MAUS-2; 0.37- and 0.82-fold in JS-335, respectively. In the soybean callus suspension culture, biosynthetic genes were used to validate the effects of elicitor on isoflavones. Both biotic and abiotic treatments contribute to the upregulation of IFS1 and IFS2 expression, that in turn, leads to the accumulation of isoflavone in seed development as well as in suspension cultures. These data further suggested that the IFS2 is the key gene responsible for the isoflavone accumulation during elicitor treatment.

Influence of Exogenous Salicylic Acid and Nitric Oxide on Growth, Photosynthesis, and Ascorbate-Glutathione Cycle in Salt Stressed Vigna angularis.

The present study was carried out to investigate the beneficial role of exogenous application of salicylic acid (1 mM SA) and nitric oxide (100 μM NO) in preventing the oxidative damage in Vigna angularis triggered by salinity stress. Salinity (100 mM NaCl) stress reduced growth, biomass accumulation, chlorophyll synthesis, photosynthesis, gas exchange parameters, and photochemical efficiency (Fv/Fm) significantly. Exogenous application of SA and NO was affective in enhancing these growth and photosynthetic parameters. Salinity stress reduced relative water content over control. Further, the application of SA and NO enhanced the synthesis of proline, glycine betaine, and sugars as compared to the control as well as NaCl treated plants contributing to the maintenance of tissue water content. Exogenous application of SA and NO resulted in up-regulation of the antioxidant system. Activities of enzymatic antioxidants including superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), and glutathione reductase (GR), as well as the content of non-enzymatic components, were more in SA + NO treated seedlings as compared to control and salinity stressed counterparts resulting in significant alleviation of the NaCl mediated oxidative damage. Content of nitrogen, potassium, and calcium increased due to SA and NO under normal conditions and NaCl stress conditions while as Na and Cl content reduced significantly.

Interactive effect of salinity stress and foliar application of salicylic acid on some physiochemical traits of chicory (Cichorium intybus L.) genotypes

Chicory (Cichorium intybus) is an important medicinal, food and feed plant. Salinity can affect its growth and quality to some extent. However, adverse effects of salinity may be alleviated upon selecting salt tolerant genotypes and application of salicylic acid. Therefore, a 2-year pot experiment was conducted with three salinity levels (control, 65 mM and 130 mM NaCl), three levels of foliar application of salicylic acid (0, 0.5 mM and 1 mM SA) and seven chicory genotypes (Ardestan, Hamedan, Shiraz, Mazandaran, Sanandaj, Kashan and Yazd). Treatment characterized with 65 and 130 mM salinity levels led to significant decrease in relative water content (RWC), membrane stability index (MSI), chlorophyll a(Chl a), chlorophyll b (Chl b) and carotenoid (Car) contents and shoot dry weight (SDW) while significant increase in leaf proline (LPC) and malondialdehyde (MDA) contents. Moreover, the highest changes in measured traits were observed at salinity level of 130 mM. Salicylic acid application at levels of 0.5 and 1 mM SA significantly ameliorated all measured traits and the greatest values were attributed to 1 mM SA. Among genotypes, Sanandaj accounted for the highest measured traits but the lowest content of MDA while Ardestan characterized with the lowest measured traits and the highest content of MDA. Salinity decreased MSI, Car and SDW while it increased LPC and MDA in all genotypes with different magnitude. Application of SA reduced MDA in all genotypes and also led to increase in RWC, MSI, Chl a, Chl b, Car, LPC and SDW and diminution in MDA under control and specially under salt stress conditions. Sanandaj with the application of 1 mM SA under control and saline conditions was the best genotype among all genotypes. The results suggested that SA may improve performance of chicory genotypes under control and saline conditions by announcing physiochemical traits.

The role of phytochromes in Nicotiana tabacum against Chilli veinal mottle virus

It has been reported that phytochrome A (phyA) and phytochrome B (phyB) are potent regulators of plant defense. However, the mechanisms that phytochromes use to interfere with plant resistance to viral infection remain largely unclear. In this study, Chilli veinal mottle virus (ChiVMV) was used to investigate the role of phytochromes in response to biotic stress. Our results showed that the phytochromes mutant phyAphyB28 plants displayed more serious necrosis and dwarf phenotypes compared to that of wild type plants (WT) after ChiVMV infection. qRT-PCR and Western blot analyses indicated that the expression and accumulation of ChiVMV were higher in phyAphyB28 mutants than that in WT plants. The leakage (EL) and the content of thiobarbituric acid-reactive substance (TBARS) suggested that phyAphyB28 mutants suffered more severe membrane damage than that of WT plants. In addition, extensive ROS accumulated in phyAphyB28 mutants after ChiVMV infection, whereas ROS production in WT plants were much less than mutant plants. The activities of antioxidant enzymes were down-regulated in phyAphyB28 mutants when compared with that in WT plants under ChiVMV infection. Besides, the contents of endogenous SA, JA and the expression of both hormones signaling related genes were lower in phyAphyB28 mutants compared to that in WT plants. Application of exogenous SA and JA could alleviate disease symptoms. Taken together, these results demonstrated that phyA and phyB positively regulated plant defense responses to ChiVMV infection and this process was dependent on the SA and JA defense pathways.

Influence of Salicylic Acid on Growth, Yield and Macro-elements Absorption of Fennel (Foeniculum vulgare Mill.) under Water Stress

The present study was conducted in order to investigate the effect of salicylic acid on growth, yield and macro-elements absorption of fennel in split-plot as base on randomized complete block design (RCBD) with three replications in Tehran, Iran. Irrigation regime as main plot was undergone in 5 levels that included: I1: full irrigation, I2: cut off irrigation at stem elongation stage, I3: cut off at budding stage, I4: cut off irrigation at 50% flowering stage and I5: cut off irrigation at grain filling stage. Foliar application of SA (0, 3, 6, and 8 mM) as sub plot was applied at stem elongation, budding and 50% flowering stages. Result indicated application of SA was resulted to increase biological yield in all irrigation regimes. However, application of 6 mM SA had the most biomass under water stress at grain filling stage. Interaction of water stress and SA demonstrated that application of 3 mM SA had the most grain yield under full irrigation, water stress at stemming and water stress at grain filling stages, while application of 9 mM SA had the highest grain yield under water stress at budding and 50% flowering stages.

Salicylic acid modulates cutting-induced physiological and biochemical responses to delay senescence in two gerbera cultivars

The postharvest longevity of gerbera (Gerbera jamesonii) flowers has a critical importance in determining their commercial value; and therefore, there is a commercial demand for prolonging their vase life (VL). Here, we tested the efficacy of salicylic acid (SA, 150 µM) preservative in extending longevity of cut flower of two gerbera cultivars, namely the ‘Sunway’ and ‘Bayadere’, of which water-held ‘Bayadere’ has longer VL than water-held ‘Sunway’. The results indicated that exogenous SA could significantly prolong the VL of cut flowers of both ‘Sunway’ and ‘Bayadere’ cultivars, with better preservative effect being observed on ‘Sunway’. SA preservative was more effective in ameliorating relative water uptake and relative fresh weight in ‘Sunway’ than in ‘Bayadere’, which was accompanied by a greater decrease in proline accumulation. Application of SA prolonged the VL of two cut gerbera flower cultivars by inhibiting the activity of polyphenol oxidase involved in browning reaction, and decreasing oxidative stress through improving reactive oxygen species-scavenging antioxidant capacity, which included accumulation of total phenolic compounds and total flavonoids, and enhancement of enzymatic antioxidant activities. As a result, membrane lipid peroxidation levels were reduced in cut flowers of both cultivars, with higher reduction level being observed in ‘Sunway’ than in ‘Bayadere’. Additionally, SA preservative was more efficient in maintaining a greater content of total soluble proteins in ‘Sunway’ than in ‘Bayadere’. These findings clearly demonstrated that SA has higher preservative effects on extending VL of ‘Sunway’ than that of ‘Bayadere’. Taken together, SA can be recommended to farmers for postharvest treatments to maintain quality and delay senescence of gerbera flowers.

Reduced complexity satellite broadcast receiver with interference mitigation in correlated noise

Summary The recent commercial trends towards using smaller dish antennas for satellite receivers and the growing density of broadcasting satellites necessitate the application of robust adjacent sa...

Morpho-physiological and yield responses to exogenous moringa leaf extract and salicylic acid in maize (Zea mays L.) under water stress

ABSTRACTTwo field experiments were executed to investigate the effects of foliar-applied moringa (Moringa oleifera) leaf extract (MLE; 1:30 w/v) and salicylic acid (SA; 0.5 mmol), singly or in combination, on growth, physio-biochemical, yield attributes and water use efficiency (WUE) of maize (Zea mays L., Three Ways Cross 329) under full and deficit irrigation conditions. Deficit irrigation was carried out by withholding water for 36 d from 12 to 48 days after sowing (DAS). At vegetative stage, deficit irrigation significantly decreased all growth criteria, chlorophyll a concentration, and relative water content (RWC). In contrast, deficit irrigation considerably increased the concentrations of carotenoids, proline, membrane permeability (MP) and malondialdehyde (MDA). Similarly, grain yield, most yield components and WUE were significantly depressed in drought-stressed plants. However, foliar-applied treatments particularly MLE+SA significantly increased growth traits, photosynthetic pigments, RWC and proline accumulation associated with a simultaneous decrease in MP and MDA concentration under full and deficit irrigation conditions. The application of MLE+SA markedly increased grain yield, yield components and WUE over control (spray tap water). Overall, the combined application of MLE and SA could be used for alleviating the adverse effects of growth, physiology, yield criteria and WUE in drought-stressed maize plants.

Seed pretreatment and salt tolerance of dill: Osmolyte accumulation, antioxidant enzymes activities and essence production

Abstract A Factorial experiment based on randomized complete block design with three replications was carried out to evaluate performance of dill (Anethum graveolens L.) plants under a non-saline (control) and three saline (4, 8 and 12 dS m−1 NaCl) conditions in response to seed polymer coating and priming with SA and GA3. The dill plants accumulated high Na+ in roots rather than in leaves. Whereas, higher K+ content was recorded in leaves, compared with roots. Proline, glycine betaine and soluble sugars of dill leaves were enhanced by increasing salinity. Leaf water content did not change up to 8 dS m−1, mainly due to the maintenance of K+ and accumulation of osmolytes. Seed coating with hydrophilic polymer resulted in holding more Na+ ions around the seeds, leading to higher absorption of this ion by roots and leaves, thereby limiting K+ content. The reduction in K+ content of the plants limited the activity of antioxidant enzymes such as SOD, AXP and POX, leading to the reduction of essential oil content and yield of dill organs under severe salinity. However, application of GA3 and SA in particular enhanced K+/Na+ ratio, accumulation of osmolytes (such as proline, glycine betaine and soluble sugars), antioxidant enzymes activities and finally essence production of dill organs under different levels of salinity. These results suggest that seed priming with GA3 and especially SA can considerably reduce some of the harmful effects of NaCl toxicity on dill plants.

Application of Salicylic Acid Improves Filling of Inferior Grains of Rice during Late Maturity under Mild Cold Stress

Medium‐ or late‐maturing varieties of rice (Oryza sativa L.) that are planted in agroecosystems in the middle and lower reaches of the Yangtze Valley of China always encounter cold stress during the late grain‐filling stage. Generally, grain yield and yield components are adversely affected under such circumstances. To alleviate these negative effects, salicylic acid (SA; i.e., SA0 [control, 0 mg L−1], SA100 [100 mg L−1], SA200 [200 mg L−1], SA300 [300 mg L−1], and SA400 [400 mg L−1]) was exogenously sprayed on plants of three rice cultivars at full heading in the field at the experimental base of China National Rice Research Institute (CNRRI) in Fuyang City, China (30°03′ N, 119°57′ E, 11 m asl). The results indicated that the mean grain‐filling rate and grain weight of the inferior grains were significantly increased under the SA200 (200 mg L−1) treatment and correspondingly contributed to a grain yield increase of 5.0 to 10.1% in comparison with the control. Further analysis showed that the SA200 treatment significantly increased the activity of the starch branching enzyme in inferior grains over the entire grain‐filling stage. Additionally, the photosynthetic rate, chlorophyll content, and soluble protein content of the flag leaf, which precisely reflected the senescence status, were significantly increased under the SA200 treatment, especially during late maturity under mild cold stress. We speculated that improved physiological changes during the late grain‐filling stage account for the increased grain weight and grain yield. Therefore, application of SA was a promising method of alleviating the adverse effects that were induced by mild cold stress on the grain yield of rice in the middle and lower reaches of the Yangtze Valley of China.

Salicylic Acid Enhances Growth and Productivity in Cabbage (Brassica oleracea var. Capitata L.) Grown Under Saline Condition

Introduction: This experiment was set up to investigate the beneficial effect of salicylic acid to reduce the harmful consequence of salinity on cabbage productivity where Salt stress severely limits plant growth, development and yield.Methods: We had grown cabbage plants under different levels of NaCl salinity (0, 4, 8 dS m -1) alone or supplemented with foliar spray of different concentrations of salicylic acid (SA, 0, 0.25 and 0.5 mM). This experiment was laid out in a randomized complete block design with three replications. Collected all data were statistically analyzed following the analysis of variance (ANOVA) technique using MSTAT-C program and the mean differences were adjudged by least significant difference (LSD) test at 5% level of significance.Results: Results showed that, higher concentrated salt treated plants give the significant lower growth and head yield. Plant growth as well as yield of cabbage such as heads thickness, diameter and weight were decreased with increased level of salinity such as 8 dS m-1 compared with other treatment. While, foliar application of SA increased growth and yield also hindered stress induced growth and production inhibition. The improvement in plant height, leaf number, leaf length and breadth, foliage coverage, number of root and weight, head thickness, diameter and weight were increased with increased concentration of SA and higher value were recorded from 0.50 mM SA. Conclusions: It can be concluded that SA improve the plant defense system to resist the toxic effect of salinity.

Enhancing the Defensive Mechanism of Lead Affected Barley (Hordeum vulgare L.) Genotypes by Exogenously Applied Salicylic Acid

Lead is a non-essential element reduced plant growth and development that may cause multifarious disturbance in physiological, biochemical and structural integrity of plants. SA is an efficient signal molecule induces systemic resistance responses that control local defense reactions in plants. To evaluate the effect of SA on photosynthetic activity of Pb affected plants therefore a pot experiment was conducted on barley genotype Juo- 93 and Juo- 87 in the Old Botanical Garden, University Of Agriculture, Faisalabad, Pakistan. Three treatment levels (0, 100 and 200 µM) of lead sulphate (PbSO4) were applied in thrice replication with or without SA (0.5 mM) along half strength of Hoagland’s solution till the termination of experiment. The experiment was arranged in a completely randomized design. During course of study growth and pigments modulations were recorded. The result indicated that growth parameters such as root and shoot length, leaf area, fresh weight of shoot and root, dry weight of shoot and root were reduced under lead toxicity. Pb stress damaged the photosynthetic pigments such as Chlorophyll a, chlorophyll b, total chlorophyll and carotenoids but chlorophyll a/b was increased under Pb stress whereas exogenous application of SA alleviated the negative effect of lead toxicity. Juo- 93 showed more tolerance to Pb toxicity as compared to Juo-87.

Salicylic Acid Enhanced Photosynthesis, Secondary Metabolites, Antioxidant and Lipoxygenase Inhibitory Activity (LOX) in Centella asiatica

Aims: The primary aim of this work was to investigate the impact of foliar application of SA on the leaf gas exchange, the accumulation of secondary metabolites and Lipoxygenase Inhibitory activity (LOX) in medicinal plant C. asiatica. Study Design: The study used randomized complete block design (RCBD) replicated three rwith three replications Place and Duration of Study: Department of Biology, Universiti Putra Malaysia between January 2014 and March 2014. Methodology: Cantella asiatica was propagated in individual poly bags filled with sand, coco dust and compost in the ratio of 1:1:1 and chicken dung (50 g) per poly bag. The plant was left for a month in a nursery to be acclimatized until they were ready for SA treatment. After a month, the plants were sprayed with two concentrations (1 µM and 10 µM) of salicylic acid solution (SA). Control plants (0 µM) were sprayed with same solution but without SA. The leaf gas exchange, total flavonoid, saponin, Glutathione (GSH), Oxidized Glutathione (GSSG), Phenyll alanine lyase (PAL), Chalcone synthase activity (CHS) and Lipoxygenase inhibitory activity (LOX) was measured. Results: It was found that production of secondary metabolites (total flavonoids and saponin), GSH, GSSG, PAL, CHS and LOX were solely contributed by interaction of SA levels and plant parts in the descending manner came in leaf treated with 10 µM SA> leaf-1 µM SA>leaf 0 µM SA> stem 10 µM SA> stem 1 µM SA> stem -0 µM SA> root 10 µM SA> root-1 µM SA > root 0 µM SA. High concentration of salicylic acid application (10 µM) was found to be more effective in enhancing the leaf gas exchange traits compared to low concentration (1 µM). Interestingly, it was found that increase in net photosynthesis have a high significant correlation with total flavonoid, total saponin, GSH, GSSG and LOX, indicating that up-regulation of photosynthetic capacity of C. asiatica treated with SA, enhanced the production of secondary metabolites, antioxidant and Lipoxygenase inhibitory activity (LOX). This study also showed that there was involvement of CHS and PAL activity in an increase in the production of secondary metabolites and antioxidant activities under SA application. Conclusion: It was found that SA enhances photosynthetic capacity of C. asiatica. This might be due to increase in PAL and CHS activity that was observed during the study. Furthermore, the production of secondary metabolites, antioxidant enzyme and Lipoxygenase inhibitory activity was elevated during the foliar SA application.

Salicylic Acid and Calcium Treatments Improves Wheat Vigor, Lipids and Phenolics Under High Salinity.

Seed vigor is a complex physiological trait required to ensure the rapid and uniform emergence of plants in the field under different environmental conditions. Therefore, salicylic acid (SA, 0.5 mM) and calcium (Ca2+, 50 mM) priming were used as exogenous growth enhancers to stimulate wheat (Triticum durum Desf. cv. Yelken) seed vigor under high salinity. The main aim was to address whether priming of wheat with SA, Ca2+ and SA+Ca (SA, 0.5 mM + Ca2+, 50 mM; their combination) could bring about supplementary agronomic benefits particularly under stressful environments such as salinity. Exogenous application of SA or Ca2+ alone improved plant behavior in the presence of salinity stress. Nevertheless, the best results in terms of growth, seed vigor and total phenolic - flavonoids, chlorophyll - carotenoids contents and phenylalanine ammonia-lyase (PAL), ascorbic acide oxidase (AAO) activities and lipid peroxidation levels (LPO) were obtained in response to the combined SA+Ca treatment.