Iranian Journal of Plant Physiology
Volume:11 Issue: 1, Autumn 2020

Organic fertilizers play a significant role in organic systems and sustainable soil management. In general, organic fertilizers increase soil fertilization so can reduce the negative effects of the excessive use of chemical fertilizers and synthetic man-made fertilizers. This study was carried out in the Medicinal Plants Farm of Shahid Bakeri Higher Education Center of Miandoab during summer 2017. Thus, the main objective of the present investigation was to study the effect of organic and chemical fertilizers on the morpho-physiological (Diameter of plant, Plant height, Number of branch, 1000-seed weight, and Seed yield), biochemical contents (amount of N, P, K, Soluble sugar, Carotenoids, Chlorophyll a, b, total phenol content, and Proline content) and essential oil content of ajowan. The results showed that the fertilizers could significantly enhance all determined factors as compared to control samples. Vermicompost had better effect than chemical fertilizer in some factors including total phenol, chlorophylls, carotenoids, total soluble sugar, nitrogen, phosphate and potassium contents (p <0.05). The vermicompost as a potential source of plant nutrients for sustainable ajowan production can reduce health and environmental problems.

Members of Ganoderma genus, belong to Basidiomycota, such as Ganoderma applanatum and Ganoderma lucidum have been noticed in traditional and modern medicine and pharmacology for their medicinal properties and bioactive compounds. The present study is undertaken to determine whether there is difference between chemical properties of G. applanatum and G. lucidum. The fresh mature fruiting bodies of fungi growing on common hornbeam (Carpinus betulus), were collected in Neka, a county in Mazandaran Province, Iran, and their antioxidant activity and bioactive compounds content were examined by spectrophotometer and HPLC method. According to the chemical analysis, the total phenols and flavonoids content, betulinic acid and also antioxidant activity measured by DPPH radical scavenging and FRAP methods in G. applanatum were higher than the other, but G. lucidum had higher content of total polysaccharides and proteins. Also the two other terpenoids (oleanolic acid and ursolic acid) were very low in these two fungi.

Cadmium (Cd) is a phytotoxic heavy metal (HM) that can induce generation of reactive oxygen species (ROS). Arbuscular mycorrhizal fungi (AMF) are considered as bio-ameliorators that help to mitigate HM-derived oxidative stress. The objective of this study was to assess AM fungus Rhizophagus irregularis on changes in enzymatic activity and transcription of antioxidants of Medicago sativa to Cd stress. Increased superoxide dismutase (SOD) and ascorbate peroxidase (APX) transcripts accumulation under Cd stress did not lead to improvement in their activities which could be related to inactivation of enzyme resulting from excess ROS or Cd binding to the active site. However, more pronouncedly enhanced the activity of CAT instead of SOD, APX and GR in the roots of M. sativa under Cd stress conditions suggested that antioxidant enzymes differed in sensitivities to Cd exposure. AMF symbiosis significantly reduced transcripts abundance of MsCu/Zn SOD and MsCAT genes compared with NM plants indicating that metal sequestration within hyphal fungi probably made Cd concentration insufficient in root cells for induction of these genes. However, GR activity was not affected by its gene expression under Cd stress. This phenomenon might be attributed to AMF-mediated post-transcription regulation. The results presented here could provide an enlightenment to capability of Cd-induced ROS-scavenging system in M. sativa colonized with R. irregularis..

African yam bean (Sphenostylis stenocarpa) is an underexploited legume with the potential of becoming an alternative food staple to alleviate the problem of food security. An assessment was carried out on the growth and yield of AYB affected by Telfairia mosaic virus (TeMV) Infection. Telfairia mosaic virus caused severe mosaic, leaf distortion and malformation on AYB. Analyses of results revealed that TeMV caused significant (P=0.05) reduction in growth parameters of AYB; leaf area, shoot height, number of leaves produced, leaf fresh weight (FW) and dry weight (DW), relative growth rate (RGR), net assimilation rate (NAR), leaf area ratio (LAR). Results depicted differences between healthy and infected plants with percentage reduction in leaf area, shoot height, leaf fresh and dry weight at 120 DAI of 41.5%, 48.4%, 29.6% and 25.5% respectively. Relative growth rate, NAR had reductions of 27.2%, 39.1% at 30 DAI and 27.0% for LAR at 120 DAI. Infection also led to significant (P=0.05) yield loses; reduction in pod length, pod width, pod weight, number of pod per plant, number of seed per pod, number of seed per plant, 100 seed weight. The virus caused insignificant reduction in seed length and breadth. Yield reduction due to TeMV infection in pod length of 24.7%, pod weight (40.8%), number of pod per plant (22.1%), number of seed per pod (25.6%) and number of seed per plant (40.5%). The reduction in growth and yield loses occasioned by TeMV may limit the potential of AYB from becoming an alternative food source in Nigeria.

Abstract Salinity is one of the most important factors limiting plant growth and production around the world. Gibberellic acid is known as a strong growth stimulator, effective on seed germination and breaking of seed dormancy in various plant species. In order to study the response of Safflower,Sofeh cultivar, to salinity stress, a factorial experiment was conducted based on a randomized complete block designwith three replications in Pardis Agricultural Research and Education Center, Saveh, Iran. The first factor was salinity at three levels including 0, 100, and 200 mMNaCal. The second factor was seed priming with gibberellin at three levels including 0, 20, and 40 mgl-1. Findings suggested that the salinity and seed priming improved biochemical indexes of proline and peroxidase in the seedlings under study, increasing their mean germination time, germination rate, germination percentage, and chlorophyll contents. The maximum proline contents were observed in the seedlings treated with 200 mM salinity and priming with 49 mgl-1gibberelin, 3.48 mg per gram fresh weight. The maximum mean germination time, germination rate, germination percentage, and chlorophyll contents were related to 0 mM salinity and 40 mgl-1gibberellin as 2.86 days, 26.16%, 76.6%, and 8.05%, respectively. In sum, the findings suggested that priming of safflower seeds with gibberellin under saline conditions improves the plants’ resistance against salinity and their germination and growth.

Green cumin is an herbaceous, annual, delicate, and aromatic plant in the family Apiaceae, also known with other names such as " kammun " and "senut", which is among the oldest and most economical as well as the second most popular medicinal plants after black pepper. In this study, pretreatment of cumin seed was studied with plasma technology without using chemicals through damage to seed for germination. To this end, cumin seeds were examined in a control group (no treatment) and treatment with cold plasma for 5 and 10 minutes in other groups. The physiological activities of catalase (CAT), peroxidase (POX), and superoxidase (SOD), as well as malondialdehyde and soluble sugars were studied in the samples. According to the results, mean growth of seeds in 5 min plasma treatment was higher than the control and 10 min exposure groups. Mean activities of CAT, POX, SOD, and soluble sugars were higher in plants obtained from 5 min plasma irradiation than the control and 10 min plasma treatment. It can be concluded that treatment of cumin seeds with plasma increases SOD and CAT antioxidant enzymes activities. Besides, seed treatment for 5 minutes led to the best results

Tomato is one of the important plants in the world as a food, medicine etc. it is sensitive to abiotic stresses and its crop is affected by them. Moreover, Ascorbic acid (AsA) is one of the universal of plant defence mechanism against the stresses specially salinity and drought to scavenger’s reactive oxygen species. According to global warming and scarcity of water resources, subsequently drying and salinization of soils; we need to investigation of AsA effects in tomato under salinity stress. In this context, effects of ascorbic acid and salinity stress on some of physiological parameters, key enzymes including SOD, APX and expression of LeNHX1 and SIERF16 genes that involved in antioxidant system were studied in Lycopersicon esculentum Mill. plants in hydroponic conditions. Our results showed that the Ascorbic acid treatments were increased activity of superoxide dismutase (SOD) and Ascorbate peroxidase (APX) and improved physiological parameters such as lipid peroxidation and Na+/K+ contents of tomato under salt stress via increases of LeNHX1 and SIERF16 genes expression.

Salinity stresses act as inhibitor factors of plant growth. They can change the physiological characteristics and limit the production of crops. Sodium nitroprusside (SNP) is a stable free radical which use as a signalling molecule in plants and participates in various plant’s physiological, biochemical and molecular processes and also in plant’s responses to environmental stresses. We investigated the effect of SNP on physiological parameters such as photosynthetic and non-enzymatic pigments, biochemical like APX and SOD enzymes and HKT1.2 and SLWRKY 8 genes expression as a molecular section on tomato under salt stress. In this study, SNP was used as nitric oxide (NO) donor. Tomato seedlings roots were subjected to various levels of salinity including 0, 40, 80 and 120 mM and SNP (0, 50 and 100 mM) for 20 days. The SNP had protective effects on photosynthetic parameters by increase in non-enzymatic and enzymatic antioxidants. It had also decrease and additive effect in HKT1.2 and SLWRKY 8 genes expression respectively.

The objective of current study was to determine the effects of non-thermal atmospheric plasma (NTAP) on physiological features of Black Cumin seeds. Black Cumin seeds were divided into 4 groups: one control group and three experimental groups. The experimental groups were exposed to NTAP for 5, 10 and 20 minutes, respectively. Then the seeds of the experimental and control groups grew for 21 days. Subsequently, total sugar levels, total flavonoid, malondialdehyde (MDA) levels and the activities of superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) enzymes were evaluated. The results showed that the concentration of sugar, total flavonoids and total proteins in the experimental groups increased significantly compared to the control group. SOD, CAT and APX activity decreased in all NTAP- treated plant significantly compared to the control group. It can be concluded that Black Cumin seed treating with non-thermal atmospheric plasma treatment may increase plant resistance by changing the enzymatic antioxidant system.

This study aimed to appraise the chemical features such as total phenol (TP), total flavonoid (TF), total antioxidant capacity based on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays of bran and grain in 10 genotypes of rice (Oryza sativa L.) grown in Iran. Based on two procedures of DPPH and FRAP, the results demonstrated that in terms of the amount of the antioxidants in the bran of genotypes of the tested rice, Genotype G4 reached the highest and genotype G6 reached the lowest mean. Also, the examination of the amount of the antioxidant in genotypes grain of the tested rice showed that genotype G4 reached the highest and genotype G6 reached the lowest mean in the antioxidant of the grain. Besides, the examination of phenol and flavonoid levels of grain and bran of the tested genotypes indicated that the genotype G3 reached the highest TP level and the genotype G4 reached the highest flavonoid level in this experiment and they were placed in group A in the mean comparison table. The correlation result between phenolic compounds and antioxidant procedures proved that there are significant correlations among traits in this study.

Salt stress is a serious problem facing plant growth and development. Selenium (Se) could improve plant growth and reduced stress. Hence, the aim of this study was to determine whether the Se application could alleviate salinity stress negative effects on Melissa officinalis L. Different salinity levels in this research were control (0), 50, 100 and 200 mM. Simultaneously, sodium selenate (Se) (0 and 50 mg L-1) was applied. Salinity showed adverse effects on different plant growth parameters as well as pigment content. Se at 50 mg L-1 increased the vegetative growth of M. officinalis plants under different salinity levels. Salt induced oxidative stress conditions by increasing malondialdehyde and proline content, and Se foliar spraying enhanced antioxidative enzyme activity such as superoxide dismutase and catalase. Compared with the control group, selenium accumulation in shoot and root significantly increased with Se levels increment. Selenium application increased N, Ca, K, and Mn accumulation. The foliar spray of Se increased Rosmarinic acid compared to salt and non-salt treated plants. It is concluded that the application of Se can mitigate salt stress damages on M. officinalis plants and enhanced mineral uptake.

Salinity of soil is a major abiotic stress limiting the crop production and growth of peppermint. The aim of study was assessment the plant growth regulators efficacy (salicylic acid (SA), jasmonic acid (JA), brassinosteroids (BRs), and non-application of hormone as control) on physiological traits of peppermint under salinity stress (0, 30, and 60 mM). The experiment was conducted using the completely randomized design (CRD) with three replications at a greenhouse in Varamin city, Iran. Results indicated that the salinity stress caused an increase in malondialdehyde and proline contents, activity of superoxide dismutase and catalase enzymes, and essential oil content while decreased total chlorophyll content and menthol percentage. In 60 mM salinity, we observed 20.10% decreases of total chlorophyll compared to the control treatment (free salinity). In the interaction effects of salinity and spraying, the highest MDA content was related to the non-application of plant growth regulators under 60 mM salinity (13.8 mol/g FW) and the lowest was the foliar application of SA under free salinity conditions (5.35 mol/g FW). The highest proline content was observed in the non-application of plant growth regulators under high level of salinity (60 mM) by 7.68 µmol/g FW, which had an increase of 73.5% compared to the control treatment. Finally, the application of growth regulators under salinity stress moderated the negative effects of salinity stress by increasing the synthesis of malondialdehyde, proline, and antioxidant enzymes.

Poor germination and low seedling growth of stevia are common problems in the cultivation of the plant. Nutri-priming is a newest, safe, easy, and effective method to increase germination characteristics and seedling tolerance against stress. The objective in this study was to assess the effect of nutri-priming with nano potassium (nano-K), paclobutrazol (PBZ), and salicylic acid (SA) on stevia seed germination indices and physiological traits under drought stress conditions (0, -3, -6, and -9 bar; induced by polyethylene glycol 8000). Results indicated that germination indices (germination percentage and rate, mean germination time, seedling length, and seedling vigor index) and photosynthetic pigment contents (chlorophyll a, b, and total) were negatively affected by drought stress. While drought stress increased activity of antioxidant enzymes (peroxidase, catalase, and superoxide dismutase) and proline content. Seed nutri-priming with nano-K + SA + PBZ was the best treatment in improving germination traits and physiological characteristics. The highest germination percentage was related to seeds that were treated by nano-K + SA + PBZ under control and -3 bar drought treatments (62.4 and 64.0%, respectively). In all drought levels, the lowest amounts of germination percentage were found in unprimed seeds. The minimum germination percentage was obtained from unprimed seeds at -9 bar (29.05% reduction compared to unprimed seeds under the osmotic potential of 0 bar). As a result, this study indicated that the use of nano-K+SA+PBZ as a pre-sowing seed treatment can promote the poor germination performance of stevia and protect from negative impacts of drought stress.

Sage (Salvia officinalis L.) is cultivated worldwide especially in Mediterranean regions in which the leaves of this herb are widely used in pharmaceutical and food industries. Brassinolides and paclobutrazol are naturally occurring substances which modulate plant growth and development events and have been known to improve the crops tolerance to biotic and abiotic stresses. The effects of spraying of 24-epibrassinolide (BRs: 0.0, 2.5, 3.0, and 3.5 µM) and paclobutrazol (PBZ: 17, 25, and 34 µM), different moisture conditions (I: normal irrigation or non-stress, reduced irrigation or non-stress, reduced irrigation or slight drought, and deficit irrigation or mild drought stress), and interaction effects of BRs × I and PBZ × I on the morphological and biochemical parameters of the S. officinalis leaves were investigated. Reduction in level irrigation led to decrease plant height, the numbers of branches, fresh herbal and dry weight, fresh roots and dry weight while it improved content of anthocyanin and chlorophyll. The spraying of BRs enhanced plant height, the numbers of branches, anthocyanin and chlorophyll with 3 µmolar concentration proving the best. The most values of fresh root and dry weight was associated with combination of the highest irrigation (I3) and applying 17µM PBZ. Highest value of chlorophyll a and total reached in I3×P3. Maximum content of anthocyanin and chlorophyll b were observed in BRs2×I3 and BRs2×P2 respectively. Finally, we can be concluded that the foliar spraying of BRs and PBZ improve most of the features of sage under deficit irrigation.