جستجوی مقالات مرتبط با کلیدواژه « ریحان » در نشریات گروه « علوم پایه »

Priming is the exposure of organisms or cells to a small amount of physically or chemically damaging agents that prepare the organism for subsequent stress exposure through an enhanced response. Accordingly, in this study, the effect of pretreatment of four different LED lights including red LED light, red LED light (70%) + blue light (30%), blue LED light and white LED light in comparison with greenhouse light on two green and purple genotypes of sweet basil was studied under control and salinity stress with a concentration of 150 mmol NaCl. For research, seeds of two genotypes of green and purple sweet basil were planted in pots containing sandy loam soil. After 50 days, 48 pots were transferred to a chamber containing LED lamps and 12 pots were kept in the greenhouse. After 2 weeks, the pots were transferred from the chamber containing LED lamps to the greenhouse and salinity treatment was applied for 2 weeks. The results showed that 150 mM NaCl treatment reduced the fresh and dry weight of shoot and chlorophyll a and increased the amount of hydrogen peroxide, catalase activity and total phenolic compounds in both genotypes under greenhouse light conditions. In light control conditions in both genotypes, red + blue LED light increased the fresh and dry weight of aerial parts, chlorophyll a and total phenolic compounds and decreased the content of hydrogen peroxide compared to other lights. In saline conditions, the results showed that pretreatment with red + blue LED light in green genotype and red LED in purple genotype increased shoot fresh weight (65% and 52%, respectively) and shoot dry weight (2 and 73%, respectively), chlorophyll a (98% and 58%, respectively), total phenolic compounds (2 times and 20%, respectively) and the activity of antioxidant enzymes and reduction of hydrogen peroxide content (33% and 72%, respectively) compared to plants not pre-treated with these lights. According to the results, the use of LED pretreatment (red + blue LED light in green genotype and red LED in purple genotype) by strengthening support mechanisms such as reducing membrane lipid peroxidation, increasing the activity of antioxidant enzymes, phenolic compounds and photosynthetic pigments have played an important role in improving the condition of basil in both control and salinity conditions.

Foliar application of micronutrient such as zinc is a quick and easy way to eliminate or reduce the deficiency of these nutrients in plants. In order to evaluate the effects of foliar application of ordinary and nanoparticles of zinc on the growth and antioxidant responses in medicinal plant basil (Ocimum basilicum L.), this research was conducted by complete randomized design with three replicates under greenhouse conditions. The treatments were four levels zinc oxide (0, 25, 50, 100 mg.L-1) and four levels zinc oxide nanoparticles (0, 25, 50, 100 mg.L-1). Results showed that under zinc oxide treatment at 100 mg/L, the shoot and root length, and the shoot and root dry weights were significantly increased, in compare to control. The zinc nanoparticle treatment under different levels, especially at 100 mg.L-1 had a significant increase on all growth parameters including shoot and root length, inflorescence number and length, and shoot and root dry weights in comparison to control plants. By increasing concentration of both treatments (ordinary zinc and nano-zinc), the activities of antioxidant enzymes catalase, ascorbate peroxidase and guaiacol peroxidase were elevated. Minimum and maximum amounts of growth traits and antioxidant enzymes activities were observed in control and 100 mg.L-1 zinc nanoparticle, respectively. The results from this study indicate positive and obvious effect of zinc oxide nanoparticle, compared to ordinary zinc oxide, on the growth and antioxidant enzyme activity in pharmaceutical plant basil.

Recognition of environmental factors has an important role in the success of medicinal plants cultivation. Growth-promoting bacteria, through their effects on biosynthesis cycles, cause changes in plant products. In ord levels of control (field capacity), 20% FC, 40% FC, 60% FC and 80% FC. Characteristics such as plant height, , number of leaves, leaf area fresh and dry weight of the shoot, as well as essential oil percentage and and analyzed by GC/MS yield were measured. The results showed with increasing the drought stress the growth and yield in basis decreased. But inoculation of plants with PGPR increased the growth under drought stress conditions and improved the plant performance in such conditions. The highest fresh and dry weight of shoot was in inoculated plants and irrigation control (FC) treatment and the least amount of these traits were obtained in non-inoculated plants and 20% FC treatment, these traits were reduced by 50% and 70%, respectively, compared to plants inoculated with bacteria and FC irrigation. Also, the highest percentage of basil essential oil was obtained in bacteria inoculated plants and 40% FC treatment. The highest yield of essential oil was observed in the control treatment and the effect of the bacteria was not observed. The use of growth-promoting rhizobacteria (PGPR) can improve the production of medicinal plants in environmental stresses such as drought stress and greatly repair the effects of this stress.

In order to study the effect of three types of superabsorbent polymers on biochemical characteristics of basil cultivar Keshkeni luveluo under salinity stress, an pot experiment was conducted at the research greenhouse of Ferdowsi University of Mashhad as factorial based on completely randomized design with four levels of salinity (0, 40, 80 and 120 mM NaCl in irrigation water) and four levels of superabsorbent polymers included (control, Ackoasorb, Stockosorb and Terracottem) in three replications in 2017. In first harvesting time chlorophyll a, chlorophyll b, carotenoid and total chlorophyll increased by using Terracottem 29.48, 25.20, 17.24 and 10.84 percent, respectively. At the same salinity, antioxidant activity decreased 18.25 percent with the use Stockosorb and total phenol decreased 26.31 percent by using Terracottem; proline decreased 50 percent by Ackoasorb and RWC increased 13 percent by Ackoasorb superabsorbent polymers application. In second harvesting time chlorophyll a, chlorophyll b, carotenoid and total chlorophyll increased by using Terracottem 22.58, 34.78, 10.71 and 26.66 percent, respectively. RWC increased 22.06 percent by Ackoasorb superabsorbent polymers application. Antioxidant activity, total phenolic and proline content by using Terracottem and soluble carbohydrate with the use Stockosorb and electrolyte leakage by using Ackoasorb decreased 19.93, 7.81, 44.77, 39.13 and 26.02 percent, respevtively. The results of this study showed that Terracottem was more effective than the other supearabsorbents. So that the use of this super absorbent is recommended in salt stress condition.

Basil (Ocimum basillicum L.), one of the most important medicinal plants, contains monoterpene and sesquiterpene compounds. Linalool synthase (LIS) and Germacrene D synthase (GDS) are two key genes involved in terpenes biosynthesis. In the current investigation, cleaved amplified polymorphic sequence (CAPS) markers and sequencing were used to identify single nucleotide polymorphisms (SNPs) in both genes in five different basil populations. For this means, fragments of 600 and 583 bp from the coding sequences of these genes were amplified and digested by using Pst1 and Mse1 restriction enzymes. After retrieval of the sequences of the amplified gene fragments, SNPs were identified based on multiple sequence alignment in both genes in studied basil genotypes. Out of the nine SNPs identified in LIS gene, five occurred in exon region while the number of SNPs identified in intron was four. Of the total SNPs detected in this gene, the proportion of transition was 77.8%, with frequencies of A/G: 44.4% and T/C: 33.3% and C/G and C/A (transversion) with the same frequencies of 22.2%. In GDS gene, in total, 28 SNPs was detected (seven in exon and 21 in intron) of which 67.8% was transient with a frequency of G/A: 35.7% and C/T: 32.1%, and 32.1% transversion (T/A: 7.15%, G/C: 14.3% and C/A: 10.7%). The results of the sequence alignments revealed that the highest number of the identified SNPs in the studied genes are A/G and TC.

Basil (Ocimum basillicum L.) belonging to the Lamiaceae familyis an important herbal medicinal plant that essential oils from the aerial parts of the plant have been used in food industry as an antibacterial agent and perfumery. This study was conducted in 2014 at the research farm of Department of Horticulture, Faculty of Agriculture, Ferdowsi University of Mashhad, Iran. The treatments were arranged a factorial experiment based on randomized complete blocks design with three replications. The experimental treatments were two basil populations including Varam in and Qaen and different amounts of macro and micro-elements in nine levels. The traits in this study included plant height, leaf length, leaf width, dry weight, number of leaves, number of sub branches, Chlorophyll a and b, Carotenoid and essential oil. The results revealed that the majority of these traits affected by experimental treatments.The result of mean comparisons were showed that the highest dry weight (77.66 g/m2) belonged toVaram in population by application of nano- zinc chelate fertilizer at 1.5 kg/h. Based on the results, the highest chlorophyll a (6.5 g/mg FW) was obtained in Qaen population using urea fertilizer at 60kg/ha. The Varam in population with 0.93 percent essential oil had a significant superiority to the Qaen population with an average of 0.77%V/W essential oil. In addition, application of nitrox in fertilizer at 3 kg/ha had the highest amount of essential oil (1. 09%). The Varam in population with 0.93% essential oil was better than Qaen population. Application of nitroxin bio fertilizer at 3 kg/ha also had the highest essential oil (1. 09%). The results of the present study showed that different treatments concentrations had different results on the measurement traits. It seems that application of nano chelate fertilizer and nitroxin bio fertilizer can be effectively used to improve soil, environment and human health and serve as a good substitute of chemical fertilizers.

Zinc and copper are essential elements for plant growth and development. Basil (Ocimum basilicum) is an important herb of medicine and nutrition. The aim of this study was to investigate the effect of these elements on Basil. In this study, seeds were planted in pots containing cocopeat and perlite and the four-leaf seedlings were treated with zinc sulfate at of 0, 350 and 550 micro-molar concentrations and 0, 20 and 40 micro-molar copper sulfate in three replications. After a month, accumulation of these elements, proline, soluble sugars, total proteins, photosynthetic pigment and malon dialdehyde contents, leaf area, number of leaves were investigated. The results showed that different concentrations of copper and zinc effects were not significant on germination percentage, number of leaves and stem length. However increased zinc and copper were significantly increased fresh and dry weight of root and shoot. Copper and zinc treatment had no significant effects on peroxidase and catalase enzyme activities while malondialdehyde, proline, soluble sugars, total proteins contents increased. In this study, with increased concentrations of copper and zinc in the medium, copper and zinc accumulation increased in the root. The root accumulates more ions than the shoot. The accumulation of copper (shoot and roots) and zinc (shoot) decrease with increasing concentrations of copper and zinc in the medium which shows the interaction between the two elements. No significant decrease in chlorophyll content indicates that basil is resistant to copper and zinc metals in these concentrations. Antioxidant enzymes do not activate in these concentrations

In order to investigate effects of Azomite application in reducing salinity stress in basil herb, a pot factorial experiment based on completely randomized design with three replications was conducted in the research greenhouse of Agriculture Faculty, Ferdowsi University of Mashhad. Treatments were consisted of salinity stress at three levels (0, 50 and 100 mM) as the first factor and the application of Azomite mixed with soil before cultivation at four levels (0, 3, 6 and 9 g per kg of soil) as the second factor. Vegetative traits such as plant height, number of branches, inflorescence length, leaf length and leaf fresh and dry weight were significantly decreased with increasing salinity stress. Application of 9 g/kg Azomite at high levels of salinity stress improved these traits compared to control plants (non-application of Azomite). Also, the highest chlorophyll a content was obtained in control plants (non-salinity stress) and 50 mM salinity stress treatments with application of 9 g/kg Azomite which were 8.33 and 7.48 mg/g.FW, respectively. The highest antioxidant activity (90%), total phenol (0.93 mg/g.FW) and proline (0.4 mg/g.DW) was observed in 100 mM salinity stress treatment and application 9 g/kg Azomite. The highest relative water content (RWC) was obtained under non salinity stress conditions (control) and application of 9 g/kg Azomite. In general, it could be concluded that using of Azomit as a natural substance consistent with sustainable agriculture under salt stress conditions can increase plant growth and improve Basil's biochemical traits.

Ocimum basilicum L.from Lamiaceae is used as a herb, spice and fresh vegetable. Since medicinal plants have different reactions to drought stress in the production of effective compounds, Diagnosis of medicinal plants growth under different irrigation conditions and drought stress can be a guide for growing plants in dry and low water conditions. Therefore, in order to evaluate the effect of drought stress on morphological characteristics and essential oil content, especially linalool, in different stages of plant growth of Basil plant, a completely randomized factorial design was carried out in 3 replications. The experimental treatments included three levels of dryness (no stress, mild stress and severe stress) in potted conditions, in vegetative, pre-flowering, flowering and fruit-growing stages. The results showed that drought stress had a significant effect on evaluated characteristics. So, with decreasing of soil moisture content, plant height, number and leaf area, decreased in all stages of growth and Stem diameter increased at all stages, especially in severe stress and root length, increased during flowering stage. In reproductive stages, drought stress caused a significant reduction in the number of flowers than the control. Extreme stress in flowering and fruiting stages has had decrease in the amount of essential oil production, especially linalool. However, mild stress showed increase in the production of these compounds in both steps. The highest percentage of essential oil was related to mild drought stress at flowering stage and the highest amount of linalool was due to mild drought stress in the fruiting stage.

Nickel is an essential microelement for plant growth, but upper levels of this element serve as heavy metal which create toxic effects on plants and human. Application of mineral nutrition is a useful strategy for overcoming of this serious problem. In order to investigate the effects silicon nutrition on growth and physiology indices of basil (Ocimum basilicum L.) under nickel stress condition a factorial experiment based on completely randomized design with four replication was conducted in Research Greenhouse of Mohaghegh Ardabili University at 2014-2015. Experimental factors included nickel stress(0, 75, 100 and 150 ppm) and foliar spraying of plants with 1Mm concentration of silicon and control (spraying with water). During this experiment traits such as plant height, plant dry weight, root and stem dry weight, leaf and stem number, leaf area, chlorophyll index, electrolyte leakage, relative water contents, photosynthetic pigments and antioxidant enzymes and nickel accumulation in root and aerial part of plants were measured. Results indicated that the effect of nickel stress on all of traits were significant. At 150 ppm concentration of nickel, vegetative growth criteria and biochemical characteristic of basil plants reduced significantly. Foliar spraying of silicon could be alleviated the unfavorable effects of nickel stress via increases in chlorophyll b, carotenoid and carbohydrate content of leaves and increases in catalase enzyme activity also reduction in nickel content in aerial part of plants.

Zinc (Zn
2+is one of the essential micronutrient elements for plant growth. In the present study, effect of different concentrations of zinc on some physiological and biochemical properties of basil (Ocimum basilicum) was investigated. Basil seedlings were exposed to six zinc (ZnSO 4 levels (0, 50, 100, 200, 400, and 800 mg/L) in 3 days’ intervals for a period of 30 days. The root and shoot growth, leaf number and area, photosynthetic pigments content, total soluble sugars and proteins, phenolic compounds, antioxidant power and mineral elements contents including zinc and potassium were significantly increased in effect of zinc levels up to 200 mg/L. Inversely, ferrous and calcium contents was drastically decreased concomitant with increasing zinc concentration but magnesium content remained unchanged. Our results indicated a dual role of zinc with optimum concentration of 200 mg/L, and a decrease in the root and shoot growth, pigment and phenolic contents under and over optimum concentration, whereas sugars and protein accumulation were occurred concomitantly with increasing zinc in the medium. However, the decrease of these parameters at the highest zinc concentration did not reach the level of control plants, which means that this species has a high resistance against zinc metal stress and because of the relative accumulation of zinc in polluted areas may has an important role for human nutrition. In general, the results point to important role of zinc in maintaining and protecting of basil seedlings against radical oxygen species

The aim of this study was to evaluate the effects of salicylic acid on lead toxicity in basil following lead addition to soil. This experiment was conducted as Randomized Complete Block with Factorial arrangement. Factors included the 4 levels of lead nitrate; 0 (control), 100, 200 and 300 mg per kg of soil and foliar application of salicylic acid at 3 levels of 0, 50 and 100 ppm. Phytotoxicity of Lead was determined as plant growth, concentration of photosynthetic pigments and catalase enzymes. Addition of lead significantly reduced dry weight of shoots and roots and photosynthetic pigments and increased soluble carbohydrates, catalase and peroxidase. In addition, salicilic acid spraying had a significant influence on all traits. In this study the interaction between salicylic acid and lead on shoot fresh and dry weight, root fresh weight, chlorophyll a and b, carotenoids, carbohydrates, catalase and peroxidase were significant, and salicilic acid play moderating role and reducing the negative effects of lead toxicity. The results of this experiment suggested salicylic acid application in basil can be reduced lead toxicity by increasing growth and concentration of photosynthetic pigments.

The aim of the present study was to map the morphological traits in Iranian Basil accessions (Oscillum Oscillos) by Inter Simple Sequence Repeats (ISSRs) markers.  In this experimental study, 50 Iranian basil accessions from different geographical regions were used and the experiment was based on a completely randomized design. Extracting DNA and PCR was performed with 12 ISSR primers for Basil accessions. Components of variance, general heritability, and genetic and phenotypic variation coefficients were calculated by formula. Bayesian method, linear mixed model as well as Minitab 17, DARwin 5, Structure 2.3.3, Tassel 3, and SPSS 20 software were used.  There was a positive correlation between the majority of traits for basil accessions. The highest coefficient of genetic variation was observed in stem diameter and internode length and the lowest was observed in flower number. Heritability varied between 3.63% and 94.24%. Foutrteen loci with 7 traits were recognized. The range of phenotypic changes varied from 3% to 29%. The highest number of locus was obtained for stem diameter traits and the lowest was obtained for lateral branch number. Six loci were specifically associated with only one trait and other loci were common in traits. The phenotypic variation varied between 17% and 29%.  Traits have a wide variety in Basil accessions and there is a positive correlation between the majority of them. The heritability of the traits varies from 3.63% to 94.24% and the range of the phenotypic changes varies from 3% to 29%. The highest number is for stem diameter traits and lowest is for lateral branch number. Six loci are specifically associated with only one trait and other loci are common in traits. The phenotypic variation varies between 29% ‐17%.

Chavicol -O-methyl transferase (CVOMT) is a key enzyme in phenylpropanoid pathway in basil (Ocimum basilicum L.), which is a medicinal and aromatic plant of the Lamiaceae family. In this study, the effect of chitosan elicitor on essential oils yield, phenylpropanoid components and chavicol -O- methyl transfrase gene expression under water deficit was evaluated. The plants under different irrigation regimes were treated with 0.2 and 0.4 g/L chitosan in three stages of growth. Phenylpropanoid compounds were identified by Gas Chromatography and Gas Chromatography/Mass Spectrometry (GC/MS) and the level of gene expression was monitored by Semi quantitative RT-PCR. An analysis of variance indicated that oil yield and CVOMT gene expression and methylchavicol increased under water deficit and chitosan elicitor compared to untreated plants. The changes observed in methylchavicol components were in accordance with the changes of gene expression of chavicol -O-methyl transferase. Thus, chitosan as a biotic elicitor could increase phenylpropanoid components in purple basil by increased gene expression and activity of chavicol -O-methyl transferase.

Seed pre-treatment technique has been introduced as a germination and establishment enhancer under environmental stress. In order to study the effects of priming on germination characteristics growth and some antioxidant enzymes activity of basil (Ocimum basilicum L.) under drought stress conditions, a factorial experiment in a completely randomized design with four replications, at the physiology lab of the Islamic Azad University of Ardebil in 2013 was carried out. Experimental treatments include drought stress at four levels (0, -4, -8 and -12 bar) and three pre-treatments including potassium nitrate with concentrations of 1% and 2%, water as hydro priming and control treatment. The results showed that the effect of drought stress and priming on germination components and antioxidant enzymes was significant. The results showed that drought stress reduced the percentage of germination, pace of germination, rootlet length, seedling length and increased activity of superoxide dismutase, glutathione peroxidase, catalase and ascorbate peroxidase enzymes. The results of the comparison of mean interactions of drought stress and priming showed that the maximum activity of Antioxidant enzymes were obtained by pre-treatment of potassium nitrate with a concentration of 1% in a -12 bar drought level. In general, it can be concluded that basil seed pre-treatment with 1% potassium nitrate improves the basil germination parameters under drought stress conditions and increased the tolerance of basil plant to drought stress by increasing the activity of antioxidant enzymes in the germination stage.

Use of superabsorbent polymers is one strategy for increasing irrigation efficiency and optimal use of rainfall in arid and semi-arid region. In order to increasing the water use efficiency in basil production as a valuable medicinal plants and sensitive to water stress, was conducted the research as a factorial experiment on the basis of randomized complete blocks design with three replications. The treatments were two superabsorbent polymers Stockosorb® (industrial) and malva leaf (Herbal) in four concentrations (0, 0.1%, 0.2% and 0.3% w/w on the basis of soil weight) with two application methods (mixed with soil only and mixed with soil roots). The results showed that all treatments and especially their interaction had significant and positive effects on some biochemical, biological, morphological traits and water use efficiency characteristic, except seeds swelling index. Both hydrophilic polymer (Stockosorb 0.2% mixed with soil and malva leaf 0.3% mixed with soil root) were able to reduce the drought stress intensity and improved water use efficiency (60%) in basil cultivation. Stockosorb® treatment %0.2 (mixed with soil), increased leaf number (149.89 per plant) and seed number (2125 number). Whereas the maximum content of chlorophyll “a” (30.74 mg. g-1) and one thousand seed weight (1.69 g/ per plant) were detected by using Stockosorb® (%0.2) when applied on soil roots. The best results were obtained for dry matter (2.34 g/ per plant) and biochemical traits (chlorophyll b (10.93 mg. g-1) and antioxidant capacity (87.03%)) with malva leaf treatment (%0.3) applied on soil roots and root respectively.

Copper is an essential micronutrient for plant, so that its shortage will affect plant metabolism. High levels of Cu can cause phytotoxicity through the generation of reactive oxygen species. This study aimed to investigate the effect of different concentrations of nanoparticles and chloride solution, 0,1,5,10 ppm on growth and morphology of basil. The findings indicated that reduction of germination percentage, germination speed and germination index in the presence of copper chloride solution was more than that of copper nanoparticles. The measurement of length, wet and dry weight of root and aerial organ showed the negative effect of increased concentrations of copper nanoparticles and copper chloride solution on these parameters. Chlorophyll a level in all plants under treatment was reduced with an increase in copper chloride concentrations. Also, increased concentration of copper chloride solution significantly increased flavonoid and total phenol in comparison with copper nanoparticles. Anthocyanin level in the plants under the influence of copper nanoparticles was reported to be higher than that of copper chloride. The results of this study revealed that copper nanoparticles exerted less toxicity effect on the basil plant growth than copper chloride solution.

This study was carried out to evaluate the total flavonoide, phenols, antioxidant, anti-pain and anti-inflammatory in different extracts of Ocimum ebasillicum var. purpurescens in comparison with opioid drug (morphine) in male rats. The male Wistar rats with 250±10 g weighing was used and randomly divided to five groups. Group I (treated by 0.1mg/kg acetic acid, II-IV (treated by 0.7, 0.9 and 1 mg/kgof plantextract) , V (treated by 0.1 mg/kg morphine) and evaluated by Writhing test. The total phenol and flavonoids content was evaluated by follin-ciocalteus reagent, Ammonium chloride, the antioxidant activity was measured by DPPH method and serum levels of PGE2 and SOD activity measured by ELISA Kits. According to results, the ethanol extract of plant had more content of secondary metabolites with total phenol (288.3±51.5 mg EGA/g) content, flavonoide content (154.7±1.04mg EGU/g) and the highest ability of free radicals scavenging (79.4±4.1%). There was a significant correlation between phenol- flavonoid ingredients to antioxidant activity rate and free radicals scavenging of plant (P

Drought stress is a limiting factor for production in agriculture. In order to evaluate the impact of plant growth regulators, Salicylic acid and Paclobutrazol on growth and physiological traits of Sweet Basil (Ocimum basilicum) under drought stress condition, a factorial pot experiment based on Randomized complete design with 4 replication was carried out at research greenhouse of Mohaghegh Ardabili University, at 2012. experimental treatments were including water deficit stress (100, 60 and 30% percent of field capacity), two times foliar spraying with 100 and 200 ppm of salicylic acid and Paclobutrazol with two weeks interval. Controls sprayed by distillated water. Results indicated that the effects of water deficit stress, salicylic acid and Paclobutrazol foliar spraying on plant height, leaf dry matter, number of leaves, leaf area, stomatal conductance, relative water content and phosphorous content of leaves were significant (p&le0.01x). Parallel to raising water deficit stress, plant height, leaf dry weight, leaf surface area, phosphorus content and relative water content were reduced. Foliar spraying of salicylic acid and Paclobutrazol significantly increased relative water content, chlorophyll and proline content of basil leaves under drought stress condition. for conclusion, the research work revealed that application of salicylic acid enhanced tolerance against drought stress in basil plants, and the highest values for most of traits obtained by 200 ppm foliar spraying of salicylic acid.

The current experiment was designed to evaluate the effect of plant growth promoting rhizobactria (PGPR) on chlorophyll fluorescence and some physiological parameters in basil (Ocimum basilicum L.) leaf under salinity stress. The experiment was conducted in factorial arrangement based on completely randomized design. Treatments were four levels of salt stress (0, 40, 80 and 120 mM of NaCl) and three levels of PGPR inoculation (control, coinoculation with either Azotobacter̺Ⲧ⫢陛 or Azospirillum㻇깶覨鶫㸅Ꜣ陛). The results showed that increasing salinity stress significantly increased both minimum and maximum fluorescences (Fo and Fm) and quantum yield of non-regulated non-photochemical quantum efficiency [Y(NO)], while decreased variable fluorescence (Fv), maximum photochemical quantum yield of photosystem II (Fv/Fm) and photochemical quantum yield of photosystem II [Y(II)]. The trend of chlorophyll content and chlorophyll a and b (in control treatment) increased at low and medium level of salinity while decreased at higher salinity levels. However, with increasing the salinity level the relative water content (RWC) as well as the amount of carotenoids decreased and electrolyte leakage increased. Inoculation of basil plants with PGPR significantly reduced Fo and Y(NO) while increased Fv, Fv/Fm and NPQ as compared to the uninoculted control. Among the biological treatments, Azospirillum㻇깶覨鶫㸅Ꜣ陛 by 12% increase in Y(II) and 16% decrease in Y(NO), showed the most positive effects on plant photosynthetic system. Biological treatment also improved chlorophyll content, chlorophyll a and RWC and reduced electrolyte leakage. In conclusion, the current results indicated that the ameliorate effect of PGPR particularly coinoculation of Azospirillum㻇깶覨鶫㸅Ꜣ陛 on chlorophyll fluorescence and physiological parameters improvement of basil seedling leaves under salinity stress.