جستجوی مقالات مرتبط با کلیدواژه « فعالیت آنتی اکسیدانی » در نشریات گروه « اکولوژی »

Due to the importance of Iranian Ox-Tongue (Echium amoenum) as one of the most important pharmaceutical products used in many pharmaceutical, cosmetic and health industries, this study was done for simultaneous evaluation the effect of planting date and method and different biological and chemical fertilizers on some phytochemical characteristics of Iranian Ox-Tongue in Mashhad conditions.  

A split split plots experiment based on RCBD design with three replications was conducted in 2011-2013 growing seasons, in Ferdowsi University of Mashhad, Iran. Two different planting dates (10 March 2011 and 4 April 2011), three different types of biofertilizers and chemical fertilizers, as mycorrhiza (Glomus mosseae), biosulfur, chemical fertilizer and control and two different types of planting methods (direct seeding and transplanting) assigned to main plots, sub plots and sub-sub plots, respectively.  

The results showed that the highest dry flower yield obtained in conditions of mycorrhiza application in March planting date and direct seeding. Application of mycorrhiza, biosulfur and chemical fertilizer in conditions of transplanting and March planting date increased seed yield 45, 42 and 35%, respectively. In April planting date antioxidant activity in direct seeding was more than transplanting. Application of mycorrhiza and biosulfur increased antioxidant activity 18 and 35% in direct seeding and 20 and 18% in transplanting compared to control, respectively. Mycorrhiza in April planting date increased total anthocyanin 28 and 27% in direct seeding and transplanting compared to control, respectively.  

In general, according to the results of this research, the planting method of direct seeding in March and application of ecological inputs of mycorrhiza and biosulfur is recommended to improve the yield and qualitative characteristics of Iranian Ox-Tongue.

In order to study the physiological responses of castor to foliar application of zinc nano-chelate and humic acid under limited irrigation, an experiment was conducted as split-factorial based on randomized complete block design with three replications in Damghan region during 2015-16 growing season. Irrigation as the main factor in three levels including normal irrigation (control), irrigation up to 75 BBCH (mild stress) and irrigation up to 65 BBCH (severe stress). Combination of spraying various concentrations of humic acid (non-application, application of recommended rate and two-fold recommended rate) and zinc nano-chelate (application and non-application) were as subplots of this experiment. The results showed that the effect of irrigation treatment, humic acid, and zinc nano-chelate were significant on the number of capsules, number of seeds, 100-seed weight, grain yield, oil percent, and chlorophyll content. Irrigation up to 65 BBCH resulted in a reduction of 11.9, 34.9, 24.2, 24.9, and 51.7 percent in 100-seed weight, grain yield, biological yield, percent and yield of oil compared to normal irrigation. With application of humic acid based on recommended amount obtained the highest grain yield (2098.8 kg.ha-1). Foliar application of zinc nano-chelate resulted in 14.4, 8.4 and 18.4 percent increase in the grain number, 100-seed weight, and grain yield. The highest oil content (45.4%) and oil yield (943.3 kg.ha-1) were obtained in the normal irrigation. The non-application of humic acid, as well as irrigation up to 65 BBCH, led to decrease in leaf chlorophyll content. The highest activity of superoxide dismutase enzyme was observed in non-application of zinc nano-chelate and two-fold consumption of humic acid under irrigation up to 65 BBCH conditions. The seed oil percent had a positive correlation with functional traits and total chlorophyll content and had a negative and significant correlation with antioxidant enzymes activity. Regression results showed that capsule number, 100-seed weight, grain yield, and oil yield were the main factors affecting seed oil percent. In general, the application of humic acid with recommended amounts and zinc nano-chelate led to improvement of growth and physiological traits and tolerance to limited irrigation in castor plant.

In order to study the effects of biofertilizers of nitroxin (0, 2, 4 L.h-1) and biosulphur (0, 2, 4 kg.h-1) on morphological and phytochemical traits of winter cherry (Physalis alkekengi L.) an experiment was conducted in factorial basement in randomized complete block design with nine treatments and three replications in agricultural faculty of Zanjan University in 2016. All treatments had significant effects on evaluated traits. Results showed that the highest plant height (53 cm), number of branches (58), shoot fresh weight (371.3 g), dry weight (78 g), yield per plant (82.5 g), the highest total soluble solids (16.23 Brix) and vitamin C content (120.1 mg.100g)-1 obtained from integrated treatment of 4 L.h-1 Nitroxin with 4 kg.h-1 biosulphur and had Significant difference compared with control and other treatments. The highest amount of chlorophyll content obtained from integrated treatment of four L.h-1 Nitroxin with four kg.h-1 biosulphur, and 2 kg.h-1 biosulphur whit 4 L.h-1 nitroxin respectively with 6.5 and 6.23 mg /gFW, but there arent any significantly differences between these two treatments statistically, however significantly different with other treatments. The treatment of 4 L.h-1 nitroxin caused the highest antioxidant activity (76.84 percent) and the highest physaline percent (1.56 percent of dry weight) Compared with the control and other treatments. Results revealed that application of bio-sulphur and Nitroxin bio-fertilizers caused to improvement of yield and physiological and phytochemical indices in medicinal plants of winter cherry.

High salinity is an environmental problem affecting seed germination, seedling growth and seed yield in plants. The experimental design was factorial arranged in a completely randomized design (CRD), with four replications. The first factor was soil electrical conductivity levels (1.1, 2.4, 4.9 and 6.7 dS.m-1) and the second factor was mung bean cultivars (Parto and Pakistani). Soil electrical conductivity increasing, decreased mung bean dry weight, shoot height, photosynthesis rate, chlorophyll a and b content, K犉 and K/Na ratio but increased cell membrane damage, antioxidants enzymes activates and Na content. In the both cultivars minimum shoot weight obtained from Parto cultivar and 6.7 dS.m-1 .The highest Na concentration was observed in Parto cultivar under 4.9 and 6.7 dS.m-1treatment. Stress condition increased cell membrane damage and maximum lipid peroxidation obtained from Parto cultivar under 6.7 dS.m-1. 2.4, 4.7 and 6.7 dS.m -1 soil electrical conductivity, decreased K/Na ratio to 1.1, 0.6 and 0.13 in Parto cultivar. At highest soil electrical conductivity level, Pakistani cultivar had maximum shoot dry weight , photosynthetic rate and K/Na ratio and these results indicated Pakistani cultivar was salt tolerant cultivar compared to Parto cultivar.

Water availability, especially in arid regiones, is one of the major constraints for achieving optimum growth yield. In recent years, several numbers of researches has been done with different methods on adapting plants to environmental stresses such as drought stress. In this experiment, two plant growth regulators named 24-epibrassinolide and Jasmonic acid was used to improve drought tolerance of pomegranates (Punica granatume L. cv. rabab). Treatments were three levels of irrigation included sufficient water (control), mild stress (75 % of field capacity) and moderate stress (50 % of field capacity) and 9 levels of hormones included control (water), 24-epibrassinolide (0.1 and 0.2 mg/l), jasmonic acid (1 and 2 mg/l) and their combinations. These treatments arranged in factorial experiment in the form of complete randomized block design with four replications. Plant growth regulators sprayed on the leave of fertile trees before flowering and after fruiting rapid growth. Results showed that many chemical and biochemical parameters of fruit affected by drought stress. Application of 24-epibrassinolide and Jasmunic acid growth regulators changed the amount of total phenols in peel and fruit juice. The amount of antioxidant activity in peel and fruit juice was also altered by the above mentioned plant regulators. Results also showed that application of 0.2 mg/lit of 24-epibrassinolide in combination with 2 mg/lit of jasmunic acid could ameliorate antioxidant activity in peel under control and drought stress conditions. Application of 2 mg/lit of Jasmunic acid ameliorated the activity of peroxidise enzyme in fruit juice severe drought stress. According to the results, application of Jasmunic acid, lonely, or in combination with 24-epibrassinolide could have a positive effect on antioxidant activity of pomegranate fruit under the mentioned concentrations.

Sahandian Savory (Satureja sahandica Bornm.) is an indigenous perennial aromatic plant growing in the West and North West of Iran. Its growing season starts from March till end of September. Oil and its quality are abundantly variable among different Savory species (Ahmadi et al., 2009). Although, Thymol, p-Cymene and γ-Terpinen have been determined as the main components of Sahandian Savory oil by Sefidkon et al. (2004), little data on its Phytochemistry and phenology genealogy? is available. The present study investigated the phytochemical properties of essential oils of (S. sahendica Bornm.) at different harvest times from Pakal habitat and a specimen grown in greenhouse.
The aerial parts of plants were collected on one month intervals from 20th April till 20th September. A specimen cloned from the wild plants and grown in research greenhouse, college of Agriculture, Ilam, was harvested at full blooming stage in September. Essential oils were extracted using Clevenger apparatus by hydro-distillation. Isolation and identification of oil components were carried out by gas chromatography (GC) and coupled gas chromatography with mass spectrometer (GC/MS) at Medicinal Plants and Drug Research Institute, Shahid Beheshti Medical University, Tehran, Iran. Antioxidant activity and total phenol content were measured following Singleton et al. (1999) methods, respectively.
The ANOVA showed that harvest time significantly affected oil yield of samples at one percent of probability. Mean comparison analysis revealed that the maximum and minimum oil yield were belonged to May (0.42%) and September (0.19%) harvests, respectively. The essential oil percentage of plants grown in greenhouse were extremely low and negligible samples collected from their natural habitat. Analysis of variances for antioxidant activity and total phenol content showed that the traits were also significantly affected by harvest time. The highest and lowest antioxidant activity recorded for harvests in September (61.06%) and August (49.53%), respectively. On the other hand, maximum and minimum total phenol content recorded from samples harvested in September (432.71 mg Gallic acid/ ml essential oil) and June (191.28 mg Gallic acid/ml essential oil), respectively. Phytochemical analysis by coupling gas chromatography with mass spectrometer (GC/MS) identified 75 different components. ANOVA of oil compositions exhibited a highly significant difference between different harvest times. Borneol was the main component of oil at all harvests. In early stages (April and May), Borneol (29.34 and 34.58 percent), Bornyl acetate (12.96 and 9.42 percent), Linalool (7.64 and 9.35 percent) and α-Terpineol (7.09 and 8.26 percent) were the main components. By the end of spring (Mid June) Borneol and Camphor content was increased slowly so that Borneol reached to its peak (44.71 percent) in end of June, but the other main components were declined by the last harvest. On full flowering stage (mid-August and early-September) an increase was recorded for Bornyl acetate, the highest content of Camphor observed; Carvacrol was identified as the main oil component (4.92 percent) and Borneol content decreased. Phytochemical composition of oils extracted from greenhouse sample at flowering stage was significantly different from those obtained from wild plants at the same growing stage. Plants grown in the greenhouse were rich in Borneol, Bornyl acetate, Carvacrol, Camphor and Camphene (39.02, 9.54, 7.88, 7.56 and 5.93 percent, respectively), while oils extracted from wild plants, mostly formed by Borneol, Camphor, 4-Terpineol, Bornyl acetate and Carvacrol (29.30, 15.26, 11.82, 9.25 and 4.92 percent, respectively). The results showed that growing Sahandian savory in the greenhouse which is free from climatic stresses may be led to beneficial changes in its essential oil composition.
The study revealed that the highest essential oil can be achieved in May, the best quality essential oil regarding antioxidant activity and total phenol content should be obtained at the full blooming stage and to get the highest amount of Borneol, harvest must be done in July under Ilam province conditions.
Acknowledgments The authors acknowledge the financial support of the project by Dean, College of Agriculture; and Vice President for Research and Technology, Ilam University, Ilam, Iran.