نشریه فیزیولوژی محیطی گیاهی
پیاپی 70 (تابستان 1402)

The aim of this study was to investigate the interaction of salinity and chromium stress on some biochemical characteristics of portulaca oleracea. This study was conducted in a completely randomized greenhouse design with 3 replications. 4 salinity levels (0, 4, 8 and 12 ds/m) were provided using sodium chloride every 4 days through irrigation and chromium treatment levels (0, 7, 14, 21 and 28 mg/kg dry weight of soil) and before from seed cultivation in soil, different levels of chromium treatment were obtained by increasing potassium dichromate to soil. The levels of Soluble and insoluble carbohydrates in alcohol, proteins, proline, malondialdehyde and hydrogen peroxide were measured after 60 days of plant cultivation. The results showed that with increasing levels of chromium and salinity, the amounts of proline, peroxide, malondialdehyde, soluble carbohydrates increased, but insoluble carbohydrates and proteins decreased. The lowest amount of insoluble carbohydrates and proteins and the highest amount of proline, peroxide, malondaldehyde and alcohol-soluble carbohydrates were observed in the combined stress of salinity levels of 12 ds/m and chromium 28 mg/kg. The combined stress of salinity and chromium caused a further reduction in insoluble carbohydrates and portulaca protein.

Dunaliella salina is a carotenoid-producing microalgae that is important for its extraordinary ability to accumulate ß-carotene. Therefore, an experiment was performed to investigate the effect of different concentrations of gibberellic acid on growth, accumulation of chlorophyll pigments, carotenoid content, and dry biomass of D. salina in f/2 medium. Experimental treatments included different concentrations of gibberellic acid (GA3): 0 (control), 0.5, 5, 10 and 20 mg/L. The measured traits in this experiment included growth rate and doubling time, chlorophyll a, chlorophyll b, total chlorophyll, total carotenoid, dry biomass, total lipid content, and endogenous gibberellic acid. The analysis of variance showed that the effect of different concentrations of gibberellic acid on all studied traits in D. salina was significant at the statistical level ρ)≤ 0.05). Gibberellic acid (GA3) at a concentration of 10 mg/l increased growth rate, chlorophyll a and b content, total chlorophyll content, dry biomass and total lipid content in the studied microalgae. While the highest amount of total carotenoid accumulation was recorded for 5 mg/L GA3 treatment. According to our findings, it is suggested that 5 mg/L GA3 concentration can be effective, if the purpose of cultivating this microalgae species is to produce carotenoid, but if the aim of production are dry biomass and total lipid content, the use of 10 mg/L GA3 concentration will stimulate and increase the production of microalgae total lipid and dry biomass.

In order to study of the effect of foliar application of salicylic acid and biofertilizerson on yield and some biochemical traits of basil (Ocimum basilicum L.) under water stress, was investigated using a factorial experiment based on a randomized complete block design in triplicate within the 2019 crop year in the protected area of Horand city of the province of East Azarbaijan. Experimental treatments included the first factor of drought stress at three levels (70, 140 and 210 mm of evaporation from Class A evaporation pan), the second factor of seed inoculation with bacteria at five levels (no inoculation as control, inoculation with Azotobacter, Pseudomonas, Azospirillum and co-inoculation with Azotobacter, Pseudomonas and Azospirillum), and the third factor of salicylic acid foliar application at four levels (0, 0.5, 1 and 1.5 mM). With the application of dehydration, cell membrane stability, maximal photochemical efficiency of photosystem II and grain yield in basil decreased and carbohydrate accumulation, antioxidant enzyme activity, malondialdehyde content and essential oil content increased. The results of comparing the mean interaction of drought stress and biofertilizers showed that the highest grain yield (917.11 kg / ha) and maximum photochemical efficiency of photosystem II (0.713) were obtained from 70 mm evaporation treatment and the co-inoculation of bacteria (Azotobacter, Pseudomonas and Azospirillum). Salicylic acid (SA) foliar application increased 41.33%, 54.17%, 24.43% and 38.98% of glutathione peroxidase activity, leaf soluble carbohydrates, membrane stability index and essential oil content, and decreased the content of MDA by 54.72% respectively. According to the obtained results, foliar application with salicylic acid and the combined use of bacteria (Azotobacter, Pseudomonas and Azospirillum) could partially eliminate the negative effects of drought stress and improve the yield and quality of basil.

Chitosan is a nitrogen containing polysaccharide synthesized naturally by deacetylation reaction of chitin, which is confirmed as an efficient bio-stimulant to improve production of secondary metabolites in medicinal plants. In the present study, the effects of chitosan (0, 100, 200, 300, and 400 mg/L) on growth, photosynthetic pigments, secondary metabolites, antioxidant capacity, activity of antioxidant enzymes, quantity and quality of protein, and the expression of HMGS and HMGR genes were examined in Andrographis paniculata L. The results showed that application of chitosan significantly increased the chlorophyll and carotenoids and, as a result, increased plant growth and biomass. Chitosan treatments (300 and 400 mg/L) increased the expression of HMGS and HMGR genes in plant leaves, which was associated with a significant increase in the accumulation of total phenols and flavonoids. Also, chitosan improved the activity of superoxide dismutase and peroxidase enzymes and increased the antioxidant capacity of A. paniculata leaves. Examination of the quantity and quality of proteins showed that the intensity of protein bands with the molecular weight of 60 kD under 300 and 400 mg/L chitosan treatment and also the intensity of protein bands with the molecular weights of 35 and 20 kD under 300 mg/L chitosan treatment increased compared to the other concentrations. Therefore, these results revealed that application of chitosan can increase accumulation of secondary metabolites and the antioxidant capacity in the medicinal plant A. paniculata.

Due to the importance of using nanotechnology in sustainable agriculture to increase the quantitative and qualitative yield of agricultural products, This study aims to investigate the effect of foliar application of iron, potassium, calcium and manganese nanoparticles on some morphophysiological traits and nutrient uptake of peppermint (Mentha piperita L.) that is one of the most important medicinal plants of the lamiaceae family was done in a completely randomized design with three replications in 2018 in a greenhouse located in Islamshahr. Foliar application treatments of iron, potassium, calcium and manganese nanoclates included three levels of 2, 4 and 6 mg/l. Foliar application was applied in three stages with one week intervals and two weeks after the last foliar application, sampling was performed to evaluate the traits. The results showed that the application of nano-chelates significantly increased the evaluated traits compared to the control, so that the highest fresh and dry weight of shoots, total chlorophyll content of leaves and iron in the treatment of iron nano-chelate 6 mg/l, the highest fresh and dry weight of roots and the amount of potassium in the treatment of nano-chelate potassium was obtained 6 mg/l, also the highest amount of phenol and manganese in the treatment of nano-chelate manganese 6 mg/l, the highest amount of flavonoids and vitamin C in the treatment of nano-chelate Manganese 4 mg/l, the highest amount of calcium was observed in the treatment of calcium nano-chelate, 6 mg/l and the highest amount of essential oil was observed in the treatment of iron nano-chelate, 4 mg/l. In general, according to the results of this study, the application of iron, potassium, calcium and manganese nano-chelates with concentrations of 4 and 6 mg/l has a positive effect on increasing the productivity of peppermint.

The application of foliar spraying can be practical in critical stages for alleviating plant nutritional needs in the short term. To investigate the effect of growth enhancers in the tillering stage of wheat on the compensation of required compounds from storage sources to grain in the remobilization process in the stopping last irrigation, an experiment was carried out in a split-plot arrangement based on a randomized complete block design with three replications at the farm of Kashmar research station in 2020-2021. The main plots were two variety of wheat: V1: Sirvan and V2: Rakhshan, the subplots were growth enhancers including (T1: Control, T2: Urea phosphate (10 kg.ha-1) + solopotas (8 kg.ha-1) + amino acid (2:1000); T3: Urea phosphate (10 kg.ha-1) + solopotas (8 kg.ha-1) + micronutrient (2:1000); T4: Urea phosphate (10 kg.ha-1) + solopotas (8 kg.ha-1) + humic acid (2:1000). The results showed that the highest plant height was obtained from T3 treatment in the Sirvan cultivar. In both Sirvan and Rakhshan varieties, the highest peduncle length was recorded from a foliar spray of T3. The highest plant dry weight (1290 g.m-2) per square meter was also obtained from T2 in Sirvan. Grain weight per square meter in the Sirvan cultivar was 651, 582, and 462 g.m-2 from the application of T2, T3, and T4, respectively, which was higher than the Rakhshan cultivar in these treatments. The highest amount of photosynthesis was 19.1 μCO2mol.m-2. s-1, stomatal conductance, and intercellular CO2 (Ci) were obtained in the Sirvan cultivar by T2 application. In general, the effect of T2 treatment on photosynthesis and yield indicates compensation for the lack of grain yield (52% increase) and biomass (51%) due to the last water stop in the Sirvan cultivar.

In view of limitation of water resources in Iran, screening drought-tolerant watermelon genotypes and evaluate their response to drought stress conditions has been a research priority in country. In order to study the physiologic an agronomic response of indigenous accessions of Aliabad, Sistani and Torbat to water stress, a field study was carried out as a randomized complete block design with split plot arrangement of treatments under three water regimes, 100, 70 and 40% of required water, representing non-stress, mild stress and severe stress treatments, respectively, at Jiroft region in the spring and summer of 2017 growing seasons. The highest fruit weight and yield were at 100 and 70% required water whereas the lowest was achieved at 40% treatment. There were no remarkable differences among accessions under non-stress and 70% required water treatments while Sistani accession showed a better physiological and agronomic yield in response to increase water stress level to 40% required water. The increase of water stress led to an increase of proline concentration and activity of antioxidant enzymes of superoxide dismutase and catalase in all accessions, as this increase was higher in Sistani in comparison to other accessions. Based on the results obtained from this research, it could be state that Sistani accession with maintaining its physiological and agronomic yield showed a better tolerant under adverse condition in compared to other accessions. The utilization of indigenous and tolerant watermelon genotypes in breeding programs and irrigation managements might help in overcoming water shortage.

In order to investigate the effect of nitrogen and sulfur on quantitative and qualitative yield of rapeseed, a factorial experiment was conducted in a randomized complete block design with three replications in Research Field of Shastklateh Forest of Gorgan in 2018. Four amounts of nitrogen fertilizer 25, 50, 75 and 100 kg of pure nitrogen per hectare (from urea source) as the first factor, two amounts of sulfur fertilizer to zero (control) and 200 kg / ha as the second factor and two spring rapeseed genotypes Hyola 50 hybrid and ARGS 003 were selected as the third factor. The results showed that biological yield, grain yield, 1000-grain weight, number of pods per square meter, number of seeds per pod, protein percentage and oil percentage were affected by cultivar, nitrogen and sulfur. Comparison of the average interactions of nitrogen and cultivar showed that biological yield (8360 kg/ha), grain yield (275.6 g/m2), 1000-grain weight (4.1 g), number of pods per square meter (5323.53), Number of seeds per pod (31.64) and grain protein (24.32%), Soluble sugar (33.35 μmol/g) and total chlorophyll (1.38 mg/g) at the level of 100 kg N/ha and Hyola 50 hybrid cultivars and the highest grain oil (41.65%) at the level of 75 kg N and hybrid cultivars Monsters 50 were observed. Also, the comparison of the mean of the interaction of sulfur and cultivar showed that the highest number of latere better ability to absorb and transfer nitrogen and sulfur and therefore produce more yield.

Environmental pollution with heavy metals is one of the most serious environmental problems. There are several methods for removing heavy metals that require a lot of energy and are expensive. Therefore, the use of adsorbents such as algae has been considered. In this study, the efficiency of three species of microalgae Scenedesmus acutus, Scenedesmus incrassatulus, and Scenedesmus obliquus in adsorption of lead-heavy metal was investigated. For this purpose, pH (3 to 7), algal density (0.25 to 2 g), contaminant concentration (20 to 200 mg / l), time (30 to 150 minutes), and temperature (15 to 35 ° C) were investigated. it placed. The results showed that the rate of absorption of heavy metals by these three species was not significantly different. However, pH, algal density, pollutant concentration, time, and the temperature had a significant effect on the efficiency of algae in removing contaminants from the environment. The highest amount of lead uptake by microalgae occurred at pH 6, 25 ° C, adsorbent level of 0.5 g, contact time of 120 minutes, and density of 150 mg / l lead. Lead uptake had no effect on lipid and biodiesel production by microalgae.

Selenium with antioxidant properties, has positive effects on growth and development of biological activities of many plants but its excessive levels in soil causes physiological problems. This study was conducted to investigate the effect of selenium (bulk) and nanoselenium on some of physiological and biochemical of Vasha, in a completely randomized experiment. Selenium in form of sodium selenate was applied in nutrient solution at concentrations (0, 2.5, 5 and 10 mg L–1) and nanoselenium at concentrations (0, 2.5, 5, 10 and 20 mg L–1). The results showed that application of both bulk and nano-Se treatments significantly increased plant growth parameters (i.e. length of roots and shoot, the root and shoot fresh and dry weights), as well as the content of photosynthetic pigment, total flavonoids, total phenol, anthocyanin and carbohydrate content by 2.5 mg L–1 and 10 mg L– 1 of selenium and nanoselenium respectively. Moreover, the abovementioned concentrations were associated with a significant increase in plant antioxidant activity. All treatments reduced malondialdehyde. The most increase in chlorophyll a was observed at a concentration of 10 mg L-1 nano-Se, which decreased with increasing selenium concentration compared to the control treatment. The results showed that the positive effect of selenium on the growth and increase of phenolic compounds depends on the type and concentration of selenium application.

Peanut is one of the most important plants in the legume family and are rich in oil and protein. In order to investigate the effect of different levels of sulfur fertilizer (S) and foliar application of zinc (Zn) on the yield and concentration of oil and protein, a factorial experiment was conducted in a randomized complete block design with three replications for two year (2019 and 2020) at Astana-Ashrafieh city, Gilan province. The studied factors were included S fertilizer (from gypsum source) at four levels (0, 20, 40 and 60 kg ha-1) and Zn fertilizer (from zinc chelate source) at three levels (0, 1000 and 2000 ppm). The results showed that the interaction of S and Zn fertilizers had a significant effect on pod yield, grain yield, number of grains and pods, protein and oil concentration. Mean comparison of the studied traits also showed the highest pod yield (156 g plant-1) in the treatment of 40 kg S + 1000 ppm Zn, while the highest grain yield (92.3 g plant-1) in the treatment of 60 kg S + 2000 ppm Zn was obtained. The highest weight of 100 grains (1283.6 g) belonged to the treatment of non-using of S + 1000 ppm Zn. The highest protein concentration (17.94%) was observed from treatment of non-using of S + 2000 ppm Zn, and oil concentration (46.09%) in sulfur fertilizer treatment of 60 kg S + 1000 ppm Zn. Based on the results of this experiment, it can be stated that the simultaneous application of sulfur fertilizer and zinc foliar application significantly increases grain yield and improves yield-related traits in the peanut and it can be recommended for the climatic conditions of Gilan.