Iranian Journal of Plant Physiology
Volume:12 Issue: 4, Summer 2022

Globally environmental stress plays a significant role in the growth and development of plants,Every stress alters the signal system and eventually resulting in an end response.Combination of stress treatments can both negatively or positively effect the plant. A few studies were conducted in combination of stress treatments in ginger. In the present study the effect of different individual stress treatments and their combined treatments on the concentrations of gingerols in improved ginger variety (Zingiber officinale cv-varada) were analyzed. The different stress treatments were attempted using salicylic acid and zinc Sulphate. Along with these two, drought is also taken as a third stress. The results of Individual and combination of stress treatments were obtained. The present study gives an idea about the effect of individual as well as combined stress treatments in both morphological (yield and growth parameters) and the gingerol content. This also gives a clear picture about cross tolerance in which one stress influenced the effect of another.

A factorial experiment was conducted in a completely randomized design with four replications to investigate the effect of boron priming on the chemical and antioxidant content of seedlings of different quinoa genotypes.Experimental factors included seed priming(at six levels of control,hydropriming,and boron concentrations of 1g/L،2g/L،3g/Land4g/L) and 3 quinoa genotypes(Titicaca,Giza1 and Sajama).The traits in this study included chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, anthocyanins, saponins, total phenols, peroxidase,and superoxide dismutase.The results showed that boron priming has a significant effect on all traits.The highest levels of chlorophyll and carotenoids in Titicaca and Sajama genotypes were obtained by applying the level of boron concentrations of 2g/L,while the highest level of the mentioned traits was obtained by applying the level of 1g/L in the genotype of Giza1.In the studied genotypes,by increasing the concentration of boron solution,the saponin content increased(33.3%)and the highest level of saponin was observed in the Titicaca genotype(1.13 mg/gDW).The highest total phenol content in Titicaca and Sajama genotypes was obtained by applying boron concentrations of 1g/L,while boron priming reduced the total phenol content in Giza1 genotype,compared to hydropriming.In addition,the response of anthocyanin content to different levels of priming was different in different genotypes.The highest anthocyanin content was obtained in Titicaca genotype at 2g/L,in Giza1 genotype at 4g/L,and in Sajama genotype in control.At a boron concentration of 2g/L,the Titicaca and Sajama genotypes had the highest content of superoxide dismutase enzyme,while the genotype Giza1 had the highest level at a concentration of 1g/L.The highest peroxidase activity was observed in a boron concentration of 4g/L.

A factorial experiment was performed as a randomized complete block design with three replications in Sari Research Farm during 2016-2017. Three levels of stress, including drought stress on the time of tillering initiation (15 days after transplanting), in remobilization stage (the end of flowering and the beginning of grain filling stage), and no drought stress (control), were considered as the main factors. Four fertilizer sources, including vermicompost, Azolla compost, humic acid, and chemical fertilizers of nitrogen, phosphorus, potassium, along with two local Tarom and Shirodi cultivars, were considered as the sub-factor. The maximum paddy seed yield was obtained in the non-stress condition using humic acid in Shirodi and local Tarom cultivars. The highest harvest index in the first year under non-stress conditions was obtained from the use of humic acid fertilizer resources in the Shirodi cultivar (54.08%), and the maximum concentrations of chlorophylls a, b, and total chlorophyll were obtained under non-stress conditions. With applying stress, especially drought stress at the complete heading stage, the chlorophyll concentration significantly reduced, so that under drought stress at the heading stage, chlorophyll a, b, and total chlorophyll concentrations reduced by 3.8, 2.6, and 3.3, respectively, compared with the control. the use of humic acid is recommended to obtain the maximum functional and physiological traits of the studied rice cultivars under drought stress.

In this study, the effects of auxin and gibberellin on Euphorbia trigona plants, grown in a complete randomized blocks design under greenhouse conditions were investigated. One-minute pretreatments including auxin regulators NAA, IBA and IAA, (0, or 500 mg / l), followed by treatments containing IAA, IBA and NAA, 250 mg / l, and GA treatments,250 mg/l, without any pretreatments were utilized on 2 month cuttings. After 4 months, fresh and dry weight of shoots and roots, and shoot total terpenoid content were measured. In some samples, shoot extract was analyzed using GC-MS. Fresh and dry weight of shoot did not show any sensitivity to the treatments and pretreatments. NAA treatment had the most positive effect on root fresh and dry weight. The highest significant increase in terpenoid content was observed in NAA treatment and NAA and IBA pretreatments. GC-MS analysis showed that the type of chemical compounds in the extract were mainly including sesquiterpenes, diterpenes, fatty acids, esters and steroids with various medicinal and antimicrobial properties as well as industrial applications. Four compounds including bis-2-ethylhexyl phthalate, hexadecanoic acid, 6,10,14-trimethyl-2-pentadecanone (Hexahydrofarnesyl acetone) and neophytadiene were observed in all treatments and controls with different percentages: Bis-2-ethylhexyl phthalate in NAA treatment 49.31%, in control 9.59%; Hexadecanoic acid in NAA treatment 2.73%, in control 2.12%; 6,10,14-trimethyl-2-pentadecanone, in NAA treatment 3.16%, in control, 1.42%, Neophytadiene in control 0.94% and in gibberellin treatment 1.64%. This comparison prominently showed that hormone utilization could have a positive effect on terpenoids and fatty acids anabolic pathways in Euphorbia trigona.

This study aimed to investigate the effect of foliar application of Cycocel and micronutrients of iron and zinc on wheat yield and physiological traits under drought stress during the crop years of 2017-18 and 2018-19. The experiment was performed as a split factorial in a randomized complete block design in three replications. In this experiment, irrigation at two levels (I1: regular irrigation and I2: cut off irrigation at the beginning of the reproductive stage) was considered the main factor. Also, Cycocell at two levels (C1: non-consumption and C2: Cycocell consumption of 0.5 l.ha-1) and foliar application of micronutrients at four levels (F1: pure water, F2: foliar application of iron, F3: foliar application of zinc, and F4: foliar application of iron + zinc (each in a ratio of 3 per thousand)) were considered sub-factors in factorial. The results showed that under normal irrigation conditions, both in terms of application of Cycocell and non-application, the application of iron + zinc had the lowest amount of ascorbate peroxidase and catalase. Under water stress conditions and non-application of Cycocel, the concentration of ascorbate peroxidase and catalase decreased significantly with the consumption of micronutrients, but their concentration increased with the consumption of micronutrients and Cycocel. In general, foliar application of Cycocel and iron + zinc under stress reduced the concentration of antioxidant enzymes.

The Lamiacae family is one of the largest herbal familiesWhich has about 200 genera and two to five thousand species. This family contains important medicinal herbs. Thymus migricus and Origanum vulgar are two important species of this family that have anti-oxidant and anti-radical properties. In this study, total phenol content and anti-CAD activity of absolute ethanol extract, absolute methanol, ethanol 50%, and methanol 50% were studied in two species of Origanum.vulgar and Thymus.migricus in West Azarbaijan province.The most phenolic, flavonoid, regenerative, inhibitory power of fat peroxidation, radical accumulation power and total antioxidation were found in methanolic extract of Origanum.vulgar species.The results showed that the antioxidant activity, the free radical control, and the fracture velocity of the chain, in addition to the total phenol, depend on the nature of the compounds.Generally, Origanum.vulgar can be used as a natural antioxidant in the food and pharmaceutical industry.aaaa.aa.aaaa aa aa aa aa aa aa .

Nepeta cataria L. and Salvia sclarea L. are two species of Lamiacea family and endangered species in Yazd province of Iran. For this the reason we studied callus induction and shoot regeneration of these species and MWCNTs effects on them to improve the proliferation rate. In order to callus formation MS medium supplemented with 0.1mg l-1 Kin and 1 mg l-1 NAA were used. For shoot regeneration, MS containing 0.1 mg l-1 IAA and 1 mg l-1 BA were applied. Concentrations of carbon nanotubes at 0, 20, 60, 80 and 200 µg ml-1 MWCNTs in regeneration and callus induction media were used in both species. The results showed significant differences between using MWCNTs and control in callus induction and shoot regeneration rate. The most callus mass of N. cataria with 20 µg ml-1 was 304 mm3 whereas controls was 117.75 mm3. The highest callus mass of S. sclarea with 80 µg ml-1 MWCNTs was 414 mm3, but in controls was 182.15 mm3. Using of 20 µg ml-1 MWCNTs with 6.17 shoots per explants was the best shoot regeneration in N. catari and treatment by 80 µg ml-1 MWCNTs had the lowest regeneration rate. Using concentration of 80µg ml-1 MWCNTs with 4.2 shoots per explants led to maximum proliferation and the least regeneration was 1.85 shoots in 200 µg ml-1 MWCNTs treatment of S. sclarea. It seems that the effect of MWCNTs on propagation may be dose dependent, high concentrations of nanotubes reduce callus formation and shoot regeneration in these plants.

Many RNA-seq studies have analyzed the effects of individual biotic and abiotic stresses on gene expression in Eucalyptus. Until now, RNA-seq data has not been used to investigate the effect of several environmental stresses on the expression of gene families in one study in Eucalyptus. We organized an analysis of 18 studies that investigated the effects of various biotic and abiotic stresses on gene expression in Eucalyptus. In this study, six environmental stresses including fungus, high temperature and elevated CO2, drought, potassium deficiency, nitrogen deficiency and phosphor deficiency were used. These stresses fall into four categories including drought, climate change, nutrient deficiency and fungus. We found that the expression of over 341 gene families (protein kinase gene superfamily, Glycoside hydrolase (GH) gene family, ABC transporter gene family, etc.) in a range of Eucalyptus species and hybrids changed after exposure to biotic and abiotic stresses. Among of these gene families, only glycoside hydrolase gene family was found to be differentially expressed in all six of the stresses. The proportion of differentially expressed genes (DEG) that were down relative to up-regulation, was significantly higher in the main biological processes. Many of the gene families that responded to biotic and abiotic stresses encoded products involved in response to stimulus and metabolic process, developmental process, localization and cellular component organization or biogenesis. The results from this work will be used to further characterize the gene regulatory networks underlying stress responsive genes in Eucalyptus.