Research Article
hanifeh seyed hajizadeh; shahla safkhani
Abstract
Introduction: Fruits and vegetables play a major role in providing vitamins and minerals that are essential in the metabolism. In addition to providing vitamins and minerals compounds, they are called secondary metabolites. Tomatoes are one of the most vegetables in diets of people around the world. ...
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Introduction: Fruits and vegetables play a major role in providing vitamins and minerals that are essential in the metabolism. In addition to providing vitamins and minerals compounds, they are called secondary metabolites. Tomatoes are one of the most vegetables in diets of people around the world. Low temperature stress associated with the production of reactive oxygen species causing damage can occur before or after harvest, farm, transportation, storage and marketing. Today, a greater emphasis is placed on post-harvest storage of agricultural products to increase productivity and make better use of labor resources, worker, energy and money, rather than an increase in production. One of the most promising treatments is the use of salicylic acid for prevention of the frost damage of post-harvest fruits and vegetables with different mechanisms such as increased enzymatic and non-enzymatic antioxidant system activity. Salicylic acid is known as a signal molecule in the induction defense mechanisms in plants. SA is a well-known phenol that can prevent ACO activity that is the direct precursor of ethylene and decreases Reactive Oxygen Species (ROS) with increasing enzyme antioxidant activity. Salicylic acid is a natural phenolic compound known as a plant hormone having positive effect on storage life and quality of fruits. This study aimed to investigate the effects of pre- and post-harvest application of salicylic acid on antioxidant properties and quality of tomato and its effect was evaluated on prevention of chilling injury of cherry tomatoes during cold storage.
Material and Methods: This research was conducted in a greenhouse of Horticulture Department of University of Maragheh. Treatments were included before harvest at fruit set stage with the control (distilled water) and 0.75 mM salicylic acid spraying and after harvest, red ripened fruits were used for treatments control and immersion in 0.75 mM salicylic acid. Then all the treated fruits were transferred to 1 °C. Sampling of fruits was done weekly and continued five weeks. In the last week of the experiment, fruits were kept for three days at room temperature (24-25°C) to evaluate the effects of frost on the whole period. To determine the effect of salicylic acid on percentage of cherry tomatoes injury, analysis of variance for a completely randomized design with three replications was used. For other traits factorial experiment with completely randomized design was applied. The treatments included salicylic acid treatment and six periods of storage. Duncan test was used for comparison of means.
Results and discussions: The results showed that the effect of salicylic acid significantly reduced frost damage in cherry tomato fruits during the storage period (P≤0/01). Treated fruit with salicylic acid before harvest showed the lowest damage of chilling in comparison with controls. Titratable acidity is directly related to the concentration of organic acids present in the fruit which is an important parameter in maintaining the quality of fruits. Titratable acidity increased gradually in all treatments except control and it seems to be influenced by the postharvest SA. Cell membrane of injured tissue was exposed to transform from a crystal liquid phase to a solid gel together and thus membrane permeability and ion membrane leak were increased (Wang et al., 2006). Salicylic acid may be used in the pre-harvest cherry tomatoes had a large role in the stability of the membrane and prevention of chilling injury. Salicylic acid was used before conception and chilling injury (Wang et al., 2006). Salicylic acid may be used in the pre-harvest cherry tomatoes that had a large role in the stability of the membrane and prevention of chilling injury.. . Application of salicylic acid before harvest on cherry tomatoes was more effective in maintaining the quality of the fruit and preventing of chilling injury. Organic acids reduce the consumption of sugars that occur during breathing and are directly related to metabolic activities (Jalili Marandi, 1383; Rahemi, 1384). It seems that spraying with 0.75 mM salicylic acid before conception, had a greater impact on the accumulation of proline and resistance in the plants and so the fruit had the lowest percentage of frost and high levels of proline matches. The maximum amount of proline in fruits at low temperature was obtained by increasing the exposure time after fifth week.
Conclusion: The results of the percentage of chilling injury, proline, carbohydrate and indicators related to quality of tomato fruits cherry tomato showed that treatment with salicylic acid can be effective on chilling tolerance during storage. Compared with the control treatments before harvesting frost cherry tomato had the greatest influence on stability by increasing the number of applications of salicylic acid that also reduced the effectiveness of this treatment.
Research Article
peyman jafari; Amirhooshang Jalali
Abstract
Introduction: The fresh, steamed and boiled spinach were used because of antioxidant compounds that have great biological value. This plant is usually rich in nitrates that can play an important role in reducing heart attacks. Each year, more than 30% of the area under cultivation leafy vegetables in ...
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Introduction: The fresh, steamed and boiled spinach were used because of antioxidant compounds that have great biological value. This plant is usually rich in nitrates that can play an important role in reducing heart attacks. Each year, more than 30% of the area under cultivation leafy vegetables in Iran, was allocated to spinach. Spinach growing in both spring and autumn or summer, has poor quality due to stem production. Higher spinach yield have been reported in autumn cultivation (compared to spring or winter planting). The nitrogen-rich lands, little light condition, excessive use of nitrogenous fertilizers and plants during the growing season short cause some plants like spinach, are faced with the problem of nitrate accumulation. The accumulation of nitrate in vegetables will be different depending on the species and genetic differences.
Materials and Methods: This research was conducted for two years in Kabootarabad Agricultural Research Station of Isfahan in order to determine the most suitable planting prickly seed spinach. Each year, of experiment was based on randomized complete block design with four replications and the results were reported based on two-year combined data analysis. Five planting dates at intervals of 15 days from the beginning of September had been adjusted. Prickly seed spinach was prepared from Seed and Plant Improvement Institute. In full leaf development stage and before the harvest of each plot, 10 plants randomly were selected and measured attributes including number of leaves, leaf length, leaf width and length of the petiole. In order to assess yield, two central rows of plants per plot (surface equivalent to two square meters) were analyzed after removing two distance of half a meter from each side. Nitrate samples were analyzed using ion analyzer. Statistical analyses of the data, correlated traits were performed using SAS software and comparisons of means using LSD at 5%.
Result and discussion: According to the results, year had no significant effect on traits. 5 September sowing date, GDD=571 was diagnosed as the best spinach planting date yielding 43 tons per hectare. Delayed planting date of 5 September to 22 October showed significant yield reduction and the amount of nitrate accumulation in plants also increased linearly. Number of leaves can be changed as one of the main factors influencing the performance of spinach according to cultivar and environmental conditions and in some studies they were ranged from 12 to 23. Amounts of nitrate accumulation in spinach were 2675, 2898, 3189 and 3571 ppm of fresh weight in different planting date of 5 September (571 GDD), 22 September (354 GDD), 6 October (193 GDD) and 22 October (84 GDD), respectively. The different sowing date, petiole nitrate accumulation varied from 3513 to 4680 ppm. Nitrate accumulation was ranged from 2135 to 3125 ppm wet weight in leaf blade. Different planting dates can influence on the length of day and intensity of light and thus can affect the amount of nitrate in plant. After planting date of August 22, temperature and radiation also reduced, and therefore it is natural that reduce the activity of the enzyme nitrate reductase and be more prepared conditions for nitrate accumulation. According to the World Health Organization, the uptake of nitrate and nitrite per kg of body weight daily allowance, equal to 0.06 and 0- 7.3 mg has been reported. The quality of light received by the plant also had an effect on nitrate accumulation, and red light compared to blue light has a greater role in stimulating the enzyme nitrate reductase activity and thus is more effective in reducing nitrate accumulation.
Conclusion: Climatic conditions affect the quantity and quality of vegetative organs. The results of this study showed that unsuitable spinach planting date will reduce not only yield, but also increases the concentration of nitrate (over 2500 ppm of fresh weight) and it may causes risks for consumers.
Research Article
Kh. Parvizi; mohammadreza hassandokht; Bita Azad
Abstract
Introduction: The advantages of plastic mulches have been known in production of agricultural crops. Their capability have been demonstrated to help nutrition uptake, precocity and yield of fruit trees, and decreasing of aphid population as viruses pest vectors. It is also demonstrated some advantages ...
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Introduction: The advantages of plastic mulches have been known in production of agricultural crops. Their capability have been demonstrated to help nutrition uptake, precocity and yield of fruit trees, and decreasing of aphid population as viruses pest vectors. It is also demonstrated some advantages of plastic mulch on some traits in potato such as increasing growth rate, yield and number of medium tuber size. Also, the effects of combined use of straw, chopped and polyethylene as well as different levels of irrigation (60, 80, 100, 120% water requirement) on yield and water use efficiency in potato have been investigated. In previous studies, it is concentrated on the effect of the special type of plastic on growing aspect of potato and there is no comparative assessment between different types of the mulches. So that in this research we evaluated the responses between types of plastic mulches.
Material and Methods: this research was conducted under field conditions. A factorial experiment was designed based on randomized complete block design with three replications. The experimental treatments consisted of mulch in five levels (clear, white, black, double layer and control (without mulch)) and two cultivars (Agria and Sante). Each plot was designed in 4 m2. For every plot, ridges were divided into complicated double rows with 50 × 150 centimeters wide. Irrigation tapes were placed between every duplicated row. Water requirement was calculated through corrected evapotranspiration (ETo) by Penman-Monteith equation with considering 90% water use efficiency. During the growing season some characteristics such as requirement time to 80% emergence, tuberization time, plant height in flowering time, number of stems and leaf area have been measured. Harvesting time was recorded along with measurement of tuber weights. Total yield was measured by random selection of one m2 in each plot. Harvested tubers were separated based on three sizes; edible tuber (large tuber), average tuber and small tuber size. Tow-way analysis of variance (ANOVA) of data was carried out using SAS software and means were compared byDuncan’s Multiple Range Test at probability level of 5%
Results and Discussions: The results of the experiment showed that application of plastic mulch and cultivar had significant effect (P≤ 0.01) on most of growing traits. Effect of cultivar and plastic mulch had no significant different on tuber dry matter. Mean comparison of 80% emergence date, number of main stem, growth duration, ranking of tubers size and total yield showed significant effect between cultivars and plastic mulches. Sante cultivar with clear mulch reach in shortest time to 80% emergence (11.3 days) and tuberization time (46.46 days). Significant difference between polyethylene mulches in emergence date is due to the effect of mulch characteristics on soil temperature and moisture. Consequently, soil microclimate would be changed and growth habits of potato plant inclined to suitable responses. Clear plastic mulch had highest plant height and number of main stem compared to other mulches and control treatment. Leaf area also affected by mulches; so that four types of plastic mulches had more leaf area comparison to control. Significant effect of mulch treatments on leaf area can be related to conservation of moisture and reduction of water stress. Meanwhile, increasing of uptake and transferring of mineral nutrient can be promoted growth rate. All this reaction can increase leaf area in plastic mulch treatments. Totally, application of plastic mulches could improve growth rate, growth duration and total yield of potato.
Conclusions: The result of this research showed that polyethylene mulch can obviously increase growth rate as well reduce growth duration. Also, plastic mulch can significantly increase total yield and positive reaction effect on tuber size. Different types of plastic mulches showed different responses on growth traits and total yield. It seems clear mulch be more capable in the most traits and total yield compared with other plastic.
Research Article
ahmad sharifi; fatemeh keykha; mahboobeh yazdi; abdolreza bagheri
Abstract
Introduction: Lily (Lilium spp.) is a genus of herbaceous flowering plants, which consisted of many beautiful ornamental species with large prominent flowers. Most species are native to the Northern hemisphere temperate, though their range extends into the Northern subtropics. Some specific hybrids of ...
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Introduction: Lily (Lilium spp.) is a genus of herbaceous flowering plants, which consisted of many beautiful ornamental species with large prominent flowers. Most species are native to the Northern hemisphere temperate, though their range extends into the Northern subtropics. Some specific hybrids of Lilium spp. have been developed as cut flower in controlled conditions and in some cases can be grown as pot plant. Propagation rate of lily in natural clonal propagation methods is very low and one year produces of 1-2 bulblets per bulb scale. There is also possibility of disease transmission; so that, tissue culture techniques has provided an efficient method for its micropropagation.
Materials and Methods: In this study, two separate experiments under In vitro conditions the bulblet regeneration from thin cell layer (TCL) explants of Lilium spp. was investigated. In the first experiment, after two months the effect of TCL explants with 1, 3 and 5 mm thickness on MS medium containing 1 mg/l BA, 2ip and kin in combination with 0.5 mg/l NAA on regeneration parameters were assayed. In the second experiment to determine the effect of cultivar and cytokinin types, 3mm thickness TCL explants of five cultivars (Robina, Donato, Nymph, Lessoto and Roxana) were tested on MS medium containing different plant growth regulator (PGR) compounds including BA, kin, 2ip and TDZ at concentration of 1 mg/l in combination with 0.5 mg/l NAA. The regeneration parameters were assayed after four months. In all experiments, the medium was adjusted to pH 5.8 and autoclaved at 121°C for 15 min. All cultures were incubated at 25 ± 2°C with a 16 h photoperiod under cool white flourescent lights (30 µmol/m2).
Results and Discussion: According to the first experiment results, plant growth regulator of BA in all of surveyed parameters except root number was better than other PGRs and explants with 3 mm thickness was the best in all of parameters. The interaction of PGR and explants was significant, however maximum bulblet regeneration was observed in TCL explants with 3 mm thickness in all of PGR treatments (100%). While 1 mm thickness TCL in 2ip and 1 and 5 mm thickness TCL in Kin had the least regeneration percentage. Results revealed that the interaction of explants and medium is a key factor for suitable establishment, regeneration and growth of TCLs. Bulb dormancy is one of the limiting factors in regeneration of bulbous crop species. It seems under In vitro condition explants size and PGR combination of media especially cytokinin affected on breaking of dormancy. Maximum number of leaves and dry weight of bulblets in medium containing BA was significantly higher compared with other treatments. Most of studies confirmed the positive effect of BA on regeneration of lily. The function of cytokinin in plant promoted cell division and differentiation, which lead to growth and maintaining cells in meristematic status.
Result of second experiment showed that cultivar was one of the effective factors on regeneration trait. Oriental lily cultivar "Roxana" had the highest number of roots, bulblets, dry weight and length of plantlets and "Nymph" cultivar showed the lowest percentage of regeneration, dry weight, length of plantlets and rooting obtained. In all of cultivars BA induced more organogenesis percentage and plantlet dry weight, while TDZ induced more rooting percentage.The interaction of cultivar and PGR treatments on percentage of regenerated bulblets and rooting were significant. "Nymph" cultivar had minimum percentage of regeneration and rooting in medium containing TDZ and Kin. Furthermore, "Roxana" cultivar in medium containing BA showed the best dry weight comparison to other treatments.
Conclusion Lily has widely used in the floral industry as a cut flower or potted plant. In recent years, tissue culture was developed as reliable and highly effective method to overcome its limitations of vegetative propagation. The most advantage of this method is high multiplication rate and disease free propagation. In this study, bulblet regeneration of lilium Spp. from TCL explants under in vitro condition was considered as a highly efficient procedure for its micropropagation. With optimization of TCL system some parameters such as exogenously applied plant growth regulators, cultivar, explants types were investigated. Favorable conditions for bulblet regeneration were achieved with 3 mm thickness TCLs in MS medium containing 1 mg/l BA with 0.5 mg/l NAA. This protocol can be used for rapid micropropagation of many cultivars.
Research Article
Nasrin Farhadi; Saeideh Alizadeh Salteh
Abstract
Introduction: Allium hirtifolium commonly known as Persian shallot is an important wild medicinal plant from Alliaceae family. Persian shallot commonly known as mooseer in Iran is a perennial diploid plant that is native to Iran and grows as a wild plant throughout in the Zagross Mountains range, western ...
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Introduction: Allium hirtifolium commonly known as Persian shallot is an important wild medicinal plant from Alliaceae family. Persian shallot commonly known as mooseer in Iran is a perennial diploid plant that is native to Iran and grows as a wild plant throughout in the Zagross Mountains range, western and southwestern Iran. It is a bulbous herb and usually consists of a single main bulb or rarely two bulbs. Each bulb has a weight of about 8-15 times of a garlic clove. The bulbs of mooseer has been widely used as a traditional herb and spice plant, added to a variety of foods such as salads, pickles, yogurt and different sauces. Conventionally, Persian shallot propagates through bulbs and seeds but these two methods are not commercially efficient due to low growth rate of bulbs and deep dormancy, low viability and germination rate of seeds. In addition, the natural habitat of this plant is under increasing pressure as a result of excessive incorrect harvest that caused to damage the plant density in Iran rangelands. So, improving the efficiency of A. hirtifolium propagation is necessary. A number of positive effects on the growth and productivity of some plants through cytokinin application have been registered by earlier research. The current study aimed to evaluate the effects of pretreatment and foliar application of forchlorfenuron as a safe cytokinin on improving the bulb production, phytochemical compounds and antioxidant attributes of Persian shallot.
Materials and Methods: This experiment was done at research green house of Tabriz University in 2015-2016. For pretreated of Persian shallot bulbs, they were soaked in 0, 50 and 10 mg l-1 forchlorfenuron solutions for 24 h. Then they were cultured in pots contained perlite and vermicompost with 3:1 ratio. Foliar application was applied 2, 4 and 6 weeks after culture with 0, 50, 100 and 150 mg l-1 concentrations of forchlorfenuron. At the end of growth season the number of leaves, number of bublets, fresh and dry weight of bulblet were recorded. The phytochemical compound (protein, phenol and allicin), antioxidant enzymes (catalase, peroxidase, ascorbate peroxidases and superoxide dismutase) and antioxidant activity of bulbs were assayed with spectrophotometry methods.
Results and Discussion: Foliar applications of plant growth regulators such as cytokinins in agriculture crops are reported to be useful in controlling multiple physiological processes, including flower initiation, shoot elongation, bulb production, fruit set and as well as affected the quality characters of products. In this study despite the bulblets number that did not influence by treatments, pretreatment and foliar application of forchlorfenuron significantly increased the leaves number, fresh and dry weight of bulbs in comparison with control plants. The highest leaves number (4.49 per plant) was obtained from pretreatments. The highest fresh weight (91.77 g) was recorded at 5 and 10 mg l-1 pretreatment and 100 mg l-1 (91.63 g) foliar application. The interaction effect of treatments on dry weight was significant and the highest dry weight (19.75 g) was recorded at 10 mg l-1 pretreatment with 100 and 150 mg l-1 foliar application. Allicin content did not show significant variation between treatments and in average was 0.859 mg g-1 FW. Total phenol content significantly influenced by treatments and the highest phenol content (1.585 mg GAE g-1 FW) was recorded at 5 mg l-1 pretreatment with 100 mg l-1 foliar application. The antioxidant enzymes included catalase, peroxidase and ascorbate peroxidase that showed significant increasing under forchlorfenuron treatments. Due to significant effects of forchlorfenuron on antioxidant compounds and enzymes of Persian shallot bulbs, the assay of antioxidant activity also showed a significant increasing in treated bulbs. The maximum percent of antioxidant activity (74.522) was obtained from 100 mg l-1 foliar application. Exogenous application of cytokinins plays an effective role by protecting the fluidity and integrity of plant cell membranes. They properly mediate enzymatic (SOD, APX, and CAT) and non-enzymatic machinery with the result of preventing cell membrane damage by oxidative stress.
Conclusions: Considerable improvement in biochemical and antioxidant attributes of Persian shallot was recorded with pretreatment and foliar application of forchlorfenuron. The present data support the potential uses of the forchlorfenuron for improving the production of weighty bulbs with the high antioxidants attributes in Allium hirtifolium. Pretreated and foliar application at 5 mg l-1 and 100 mg l-1 concentrations of forchlorfenuron, respectively showed the best results and is recommendable for A. hirtifolim production.
Research Article
bahareh ghorbani; Z. Pakkish
Abstract
Introduction: Chilling injury (CI) is the primary postharvest problem of orange (Citrus sinensis L.) and many other horticultural crops during storage. Washington Navel orange fruits are susceptible to CI during storage below 5°C, and the main CI symptoms are surface pitting, browning, discoloration ...
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Introduction: Chilling injury (CI) is the primary postharvest problem of orange (Citrus sinensis L.) and many other horticultural crops during storage. Washington Navel orange fruits are susceptible to CI during storage below 5°C, and the main CI symptoms are surface pitting, browning, discoloration and decay. Several promising methods have been developed to alleviate CI symptoms of orange fruit. These include postharvest physical treatments with UV-C, modified atmosphere packaging, temperature conditioning, and chemical treatments with plant growth regulators. Oxidative stress from excessive reactive oxygen species (ROS) has been associated with appearance of chilling damage in fruits. The oxidation of ROS is due to their reaction with numerous cell components coursing a cascade of oxidative reactions and consequent inactivation of enzymes, lipid peroxidation, protein degradation, and DNA damage. Aerobic organisms have evolved well-developed defense systems to establish a fine-tuned balance between ROS production and removal plants are protected against ROS effects by a complex antioxidant system. This involved both lipid soluble antioxidant (α- tocopherol and carotenoids) and water soluble reductants (glutathion and ascorbate) and enzymes, such as catalase (CAT), ascorbate peroxidase (APX), superoxide dismutase (SOD) and peroxidase (POD). Previous studies have shown that there is a positive relationship between the antioxidant enzymes activity and the chilling tolerance in harvested fruits. Nitric oxide (NO) is an important signaling molecule involved in many plant physiological processes. It has also been indicated that NO protects plant cells against oxidative stress by reducing ROS accumulation. When exogenously applied, NO has been shown to result in an improved chilling tolerance and reduced incidence of chilling injury in several fruits. The objectives of this study were to evaluate the effects of NO on chilling injury, lipid peroxidation content, peroxide hydrogen content, and the induction of antioxidant enzymes in Washington Navel orange (Citrus sinensis L.) fruit during storage at 5±1°C.
Materials and Methods: Washington Navel orange (Citrus sinensis L.) fruits were harvested at commercial maturity from a commercial orchard in Kerman, Iran, and transported to the laboratory on the same day. Orange fruits were treated with 0.25 and 0.5 mM nitric oxide for 5 min and then stored at 5±1°C and relative humidity of 85-90 % for 5 months. No nitric oxide use was considered as control. The experiment was arranged in completely randomized design (CRD) with three replicates. Characteristics such as chilling injury, total soluble solids, titratable acidity, pH, ascorbic acid, and activity of antioxidant enzymes (peroxidase and catalase) were evaluated in the present experiment.
Results and Discussion: The results showed that use of nitric oxide in fruits reduced significantly chilling injury, ion leakage, lipid peroxidation and hydrogen peroxide compared to control, though it increased activity of antioxidant enzymes. According to these results, unlike organic acids which decreased in treated and non-treated fruits, total soluble solids, ascorbic acid and pH of the fruits increased during storage, however, nitric oxide treatment reduced the rate of changes, be either reducing or increasing, in the mentioned parameters compared to control. So, fruits treated with 0.5 mMol nitric oxide showed the highest effect on the reduction of chilling injury.
In the present study, the results indicated that NO significantly reduced CI of orange fruits during storage at 5±1 °C. NO has been applied to reduce the development of chilling injury symptoms in a number of horticultural crops. Thus NO has the potential of application in postharvest treatment by alleviating chilling injury and maintaining quality, and the aim of this study was to determine how NO alleviates the anti-oxidative systems, probably one of the mechanisms of improved chilling tolerance, of orange fruit during chilling stress. This indicates that the chilling tolerance of orange fruit was also enhanced by postharvest treatment with NO. Lipid peroxidation and protective enzyme systems are often evaluated in studies of plant mechanisms under various stresses. Low temperature disrupts the balance of active oxygen species metabolism, leading to their accumulation and destruction of scavenging enzymes such as catalase and peroxidase. In the present study, exogenous per-treatment with nitric oxide at 0.25 and 0.5 mM significantly decreased the lipid peroxidation content and electrolyte leakage of cold stored orange fruit compared to untreated fruits. The level of H2O2 was maintained by NO treatment, which led to an increase in chilling tolerance. It has been reported that the improvement of chilling tolerance in harvested horticultural crops is related to the enhancement in activates of antioxidant enzyme. Researchers found that chilling-tolerant mandarins have a higher antioxidant enzyme activity than the chilling-sensitive ones. A number of postharvest treatments that induce chilling tolerance and alleviate chilling injury also enhanced antioxidant enzyme activity. However, to the best of our knowledge, this is the first paper reporting the beneficial effects of NO on CI of postharvest orange fruits. In this study, there was a continuous increase in peel and pulp lipid peroxidation content in all fruits, but the application of NO significantly delayed the increase of lipid peroxidation. Moreover, the change in membrane permeability (revealed by H2O2 content) showed trends similar to lipid peroxidation content; in other words, peel and pulp H2O2 content increased with storage duration, but NO markedly delayed the increase. NO has been considered to be involved in a network of interacting signal transduction pathways, which regulate defense responses to abiotic stress. The detoxification of ROS is dependent on antioxidant enzymes such as CAT and POD. The increase in these enzymes’ activity contributes to the adaptation of plants to cold stress and ameliorates oxidative damage such as lipid peroxidation (lipid peroxidation increase as indicator) and H2O2 content.
Conclusion: In conclusion, application of NO reduced CI of oranges stored at 5±1°C and maintained oranges quality as well. The chilling injury, lipid peroxidation, and peroxide hydrogen were significantly reduced by NO treatment especially at 0.5 mM. Induced cold resistance by NO treatment may be due to the stimulation of antioxidant enzymes, and protection against membrane oxidative damage, decreased lipid peroxidation and H2O2 content in orange fruits. These results may have implications for the use of NO in managing postharvest CI of other subtropical fruits stored at low temperatures.
Research Article
Zhaleh Zandavifard; Majid Azizi; Hossein Aroiee; Amir Fotovat
Abstract
Introduction: Among the heavy metals, cadmium, because of high mobility and bioavailability in soil and also toxicity at low concentrations is very important. Cadmium (Cd) is known as carcinogen and can induce many types of cancers. Human activities (metallic industries, contaminated fertilizer, herbicides ...
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Introduction: Among the heavy metals, cadmium, because of high mobility and bioavailability in soil and also toxicity at low concentrations is very important. Cadmium (Cd) is known as carcinogen and can induce many types of cancers. Human activities (metallic industries, contaminated fertilizer, herbicides or insecticides, irrigation with contaminated groundwater, and use of contaminated sewage sludge) are largely responsible for accumulation of different levels of Cd in soil. Saint John’s Wort (Hypericum perforatum L.) is a medicinal plant and belongs to the family Hypericaceae which its extract, one of the best-characterized herbal medicines, known as the Cd-hyperaccumulator, is widely sold for the treatment of depression. Hyperaccumulator plants are species able to accumulate high amounts of heavy metals in their tissue at concentrations of 10 to 100 times higher than tolerated by crop plants. Zinc (Zn) is an essential element occurring in several enzymes, where it plays a catalytic or structural role. Cadmium and zinc have similar electron configuration, valence state as well as affinity to S, N and O donor ligands and thus their geochemical and environmental properties are comparable. The antagonism activity between Cd and Zn in the environment and their chemical similarity can lead to interactions between Cd and Zn during plant uptake, transport from roots to shoots, or accumulation in edible tissues. Ion exchange is one of the methods used for the removal of several toxic substances. In recent years, natural amendments, such as zeolite have been widely used to address trace metals contamination. Therefore, adding zinc and zeolite to the growth medium of plant can be moderating the toxic effects of cadmium.
Materials and Methods: This pot experiment was conducted at the Experimental Field of Ferdowsi University of Mashhad (FUM) from September 2013 to June 2014. Treatments consisted of three levels of cadmium (0, 10 and 20 mg Cd kg-1 soil), three levels of zinc (0, 25 and 50 mg Zn kg-1 soil) and three levels of Zeolite (Clinoptilolite) (0, 5 and 10g zeolite kg-1 soil) arranged in a factorial based on Randomized Complete Block Design (RCBD) with three replications. Cadmium sulfate (CdSO4·4H2O) and zinc sulfate (ZnSO4·7H2O) were purchased from MERCK company. The zeolite used in this research was collected from the Semnan mine, located in South of Semnan Province. After preparing the soil, the pots (30 cm in diameter with 18 kg capacity) were filled with 18 kg soil and thoroughly mixed with appropriate amounts of cadmium, zinc and zeolite diluted in distilled water. Seeds of H. perforatum L. cv. “Topaz” were obtained from the FUM Research Field. After 24 hours of soaking in tap water, the seeds were sown on the surface of moistened soil in each pot and germinated after 10 days. Following germination, the seedlings (about 1.0 cm high) were thinned and only 10 seedlings in each pot were kept. At the full flowering stage, these plants were harvested after 9 months. Plant height, root length, flowering stem and flower number, leaf area, relative chlorophyll and number of black nodules was measured. Chlorophyll (Chl) content were determined by leaf area meter (Li-Cor-1300,USA) and SPAD chlorophyll meter. Data were analyzed statistically by using JMP 8 and Excel software. The differences between averages were tested by Tukeyʼs test at P < 0.05.
Results and Discussion: The results showed that increasing cadmium levels lead to significant decrease of 6.28, 3.45, 2.04, 5.49, 0.82, 15.71 percents in plant height, root length, flowering stem, flower number, leaf area and relative chlorophyll, respectively compared with control. In comparison to control, the number of black nodules in leaf significantly increased by 4.23 percent. Combined application of cadmium and zinc could significantly decline the effects of cadmium on plant height and root length. Meanwhile, interaction effect of cadmium and zeolite was detected significantly on root length and number of flowers. The results of three-way interactions for root length were superior in Zn0Cd0Z10 treatment. Cadmium is an inhibitor of uptake and accumulation of essential mineral nutrients, reduces conductivity of stomata andwater potential of cells and damaged photosystems; therefore, can decrease biomass production in stem, flower and root. The reduction of Chl content could lead to enzymatic degradation of these pigments or inhibition of their biosynthesis, which could be connected with Cd-induced deficiency of iron and zinc, decrease of magnesium content or cadmium bond to essential thiol groups in both the protochlorophyllide reductase protein and other enzymes involved in the light dependent synthesis of 5-aminolevulinic acid. Heavy metal stress with impact on biosynthetic pathways of pharmacologically active molecules can either increase or decrease them. Changes in black nodules number, containing hypericin and other secondary metabolites in H. perforatum in response to heavy metals can help us understand the role of this material in stress conditions. It could be assumed that high metal accumulating ability of plants producing specific secondary metabolites in H. perforatum could be also connected with chelation of toxic metals with mentioned substances.
Conclusions: Our results confirmed that the addition of zeolite and zinc presumably improved plant growth, because of increased availability of essential nutrient elements such as K, Mg, Ca, NH4, and micronutrients in presence of zeolite or decreased Cd sorption and transmission in presence of zinc.
Research Article
Zahra Davarkhah; Bijan kavoosi
Abstract
Introduction: Table grape (Vitis vinifera L.) is one of the most important small fruits in Iran produced in a wide range of climates from temperate to tropical regions. Khoshnaw cultivar is one of the most important table grapes in Iran. Vineyard soil in many parts of Iran is calcareous, leading to the ...
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Introduction: Table grape (Vitis vinifera L.) is one of the most important small fruits in Iran produced in a wide range of climates from temperate to tropical regions. Khoshnaw cultivar is one of the most important table grapes in Iran. Vineyard soil in many parts of Iran is calcareous, leading to the decrease in the availability of micronutrients and exposure of vines to severe nutritional disorders. Lack of imbalanced fertilization is one of the reasons for the reduction in yield as well as fruit quality of vineyards. Iron, magnesium and zinc are essential nutrients that play an important role in increasing production and product quality. Zinc and iron deficiencies are the most common micronutrient disorders that have been observed in many vineyards of Iran. Other common deficiencies include manganese, boron, copper, and molybdenum. Most vineyards of Boyer Ahmad located in regions, where soil temperature is very low in spring, and obviously under these conditions and just when the grapevines need to make most of the mentioned elements, absorption of nutrients from the soil by the roots is reduced. However, there is high amount of lime (≥ 60%) in the soil of the same area in this condition with high pH (7.9). Therefore, under this situation, vines cannot uptake iron and other micronutrients including zinc and boron. The fertilizer sources and time of their application are two important factors. The aim of this study was to determine the best concentration and application time of Ferozinc fertilizer on the quantitative and qualitative characteristics of table grape cv. khoshnaw.
Materials and Methods: The experiment was conducted to investigate the effect of foliar application of some micronutrient elements before and after flowering on quantitative and qualitative characteristics of table Grape cv. Khoshnaw in Yasuj during 2012. An experiment was conducted in private vineyards in Chitab district of BoyerAhmad region. The average annual precipitation was 676.7 mm. The minimum and maximum temperatures of this area varied from -7.8 oC to 35.3oC during the year. The average minimum and maximum temperatures in growing season were 13 oC and 29.5oC, respectively. 15-year-old own-rooted vines were trained by using head system. The vines were spaced 2.5 × 3 m. They were pruned by using spur pruning which left about 60 buds on each vine. The experiment was arranged as factorial based on randomized complete block design with two factors and four replications. The first factor included different levels of Ferozinc fertilizer (0, 500, 1000, 1500, and 2000 mg/l) and the second factor included different spraying times (before flowering, after flowering, and both times). The quantitative factors measured were the average of bunch weight, and average of fruit weight per bunch; and qualitative factors were percent of soluble solids (TSS percentage), the reaction of juice (pH), total acidity (TA percentage), TSS/TA ratio and vitamin C, respectively. The data were analyzed using MSTATC package program and means were separated using Duncan's Multiple Range Test at P ≤ 0.05 and P ≤ 0.01.
Results and Discussion: Results showed that the effects of Ferozinc fertilizer application were significant (p≤0.01) on the average of bunch weight, average of fruit weight per bunch, TSS/TA ratio, pH and vitamin C content. Moreover, the effect of foliar application time on all traits was significant, except for juice pH (p≤0.01). Based on the results of mean comparison, the interaction effect between different levels of Ferozinc fertilizer and times of foliar application on vitamin C content and pH of grape juice were significant (p≤0.01). The highest cluster weight (220.222 gr), average fruit weight per cluster (215.887 gr), TSS/TA ratio (31.29), pH (3.68) and vitamin C (2.849 mg/100 cc fruit juice) were obtained in the treatment containing 1000 mg/l Ferozinc fertilizer and both application times (before and after flowering).
Conclusions: In general, the results of the present study showed that the unavailability of optimal nutritional conditions in control treatment increased the quality of fruits. Therefore when the plant is faced with nutrition abnormalities, moderate consumption of elements could enhance quantity and quality of products. According to the results of this research, application of ferozinc fertilizer at concentration of 1000 ppm before and after flowering is recommended to improve the quantitative and qualitative characteristics of table grape cv. Khoshnaw under irrigation conditions in this area.
Research Article
seyyed mousa mousavi; mehrangiz chehrazi; Esmaeil Khaleghi
Abstract
Introduction: With regard to decrease of precipitation and poor distribution of rainfall during the dry phenomenon of urban, green spaces face problems. In fact, one of the most important environmental stress is drought stress at different stages of plant growth such as seed germination, seedling establishment ...
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Introduction: With regard to decrease of precipitation and poor distribution of rainfall during the dry phenomenon of urban, green spaces face problems. In fact, one of the most important environmental stress is drought stress at different stages of plant growth such as seed germination, seedling establishment and crop production. The effect of drought stress, plants photochemical activity ceased Calvin cycle enzymes and chlorophyll content also varies in the process of photosynthesis under drought stress. Under drought stress, reactive oxygen species (ROS) such as hydrogen peroxide (H2O2), superoxide radicals (O2 • -) and hydroxide (OH •) increase their accumulation in cells that can lead to oxidative stress. To neutralize ROS, antioxidant enzymes systems in plant such as superoxide dismutase (SOD), peroxidase (POD), catalase (CAT) and ascorbate peroxidase (APX) are active. The response of antioxidants depends on the lack of water, the intensity of the stress and the type of plant species. Also, it is well known that photosynthetic systems in higher plants are most sensitive to drought stress. Indeed, drought is one of the factors affecting photosynthesis and chlorophyll content. Some of researchers reported that chlorophyll might estimate influence of environmental stress on growth because these parameters were closely correlated with the rate of carbon exchange. The aim of this study was an investigation of effect of water deficit different levels on antioxidant system and lipid peroxidation in two species of marigold. Therefore, an experiment was carried out as factorial in a randomized complete block design with three replication at Shahid Chamran University of Ahvaz in 2014 year.
Materials and methods: Experimental treatments were irrigation with three levels: 100% ETcrop (no stress), 75% ETcrop (moderate stress) and 50% ETcrop (severe stress) and two species of marigold (African and French). Catalase activity decreased absorption at a wavelength of 240 nm through catabolizing on the basis of H2O2 according to Beers and Sizer (1952). Peroxidase activity decreased absorption at a wavelength of 470 nm that was measured by using Hemeda and Kelin (1990). Ascorbate peroxidase enzyme extracted from leaf based on defects in the wavelength of 290 nm that was measured by Nakano and Asada (1987). The final product of membrane lipid peroxidation malondialdehyde concentration as the reaction thiobarbituric acid (TBA) was measured. Also, chlorophyll a, b and total chlorophyll were calculated by Arnon’s equations and chlorophyll content index (C.C.I) was measured by chlorophyll content meter (SPAD-502).
Results and discussion: Results of analysis of variance showed that irrigation treatment had significant effect on chlorophyll a, total chlorophyll (Chl a+b), chlorophyll content index and catalase peroxidase, ascorbate peroxidase enzymes activity and malondialdehyde while there was not significantly difference between two species of marigold on any of the measured biochemical characteristics. Also, results revealed that amount of leaf chlorophyll a and total chlorophyll (chl a+b) were reduced by increasing water deficit. In fact, amount of total chlorophyll, chlorophyll a, b and chlorophyll content index were higher in plants that were received 100% ETcrop than 75 and 50% ETcrop. ,The results of enzyme activity were similar to total chlorophyll and chlorophyll a and b. Amount of decreased chlorophyll a and total chlorophyll in plants were received 50% ETcrop were 24% and 47.46%, compared with 100% ETcrop, respectively.
Conclusion: Result showed that different levels of irrigation were significantly different at 5% level on catalase, peroxidase, ascorbate peroxidase enzymes activity and malondialdehyde concentration. Catalase, peroxidase, ascorbate peroxidase enzymes activity and malondialdehyde concentration were increased by reducing the amount of irrigation while there were no different between two species of marigold and interaction between species and irrigation was not effective on measured indexes.
Research Article
Esmaeil Chamani; Marzyeh Ghamari; Mahdi Mohoboldini; Alireza Ghanbari; Hamidreza Heydari
Abstract
Introduction: Crown imperial (Fritillariaimperialis L.) is an ornamental and medicinal plant native to mountainous regions of Iran. This plant genetic resources is in danger of extinction, because of grazing livestock and pest outbreaks. However, due to slow reproduction in natural conditions and traditional ...
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Introduction: Crown imperial (Fritillariaimperialis L.) is an ornamental and medicinal plant native to mountainous regions of Iran. This plant genetic resources is in danger of extinction, because of grazing livestock and pest outbreaks. However, due to slow reproduction in natural conditions and traditional multiplication methods such as scaling and Bulb division, many species of this genus are endangered. Using of biotechnology, namely in vitro plant propagation, is a solution to the problems of reproduction of rare and endangered plant species with difficult propagation and mass production of valuable genotypes. Therefore, micropropagation of F. imperialis through in vitro regeneration is essential for conservation and commercial production.
Material and Methods: The bulbs of F. imperialis in dormancy stage obtained from Ilam mountainous regions in Iran and theywere placed in wet vermiculite at 4 °C for 4-6 weeks. Then, Bulbs were surface-sterilized with 70% ethanol for 60s followed by immersion in 5% (v/v) NaOCl solution for 20min with gentle agitation, and they rinsed three times in sterile double distilled water. Explants prepared from the lower third of scales with basal plate and were placed in MS basal medium supplemented with different concentrations of NAA and 2,4-D for callus induction. Test tubes with bulb segments were maintained within 25±2°C in growth chamber at 16 hours light period by the illumination from white florescent tube light and 8 hours dark. After two months callus were transferred to MS basal medium without PGRs. Then, callus excised to 0.5 cm pieces and were transferred to MS basal medium supplemented with NAA in 0, 0.3 and 1 mg/l concentration.Three types of cytokinins with different concentrations were arranged in three seperated experiments. Thefirst experiment medium contained NAA with BA (0, 0.3, 0.5 and 1 mg/l), the second experiment NAA combined with 0, 0.1, 0.3 and 0.5 mg/l TDZ and the third experiment MS basal medium included NAA with Kin (0, 0.5, 1 and 1.5 mg/l). After three months, percentage of callogenesis, diameter of calli, percentage of regeneration, number of leaves and roots and length of leaves and roots were measured. This experiment were carried out in completely randomized design with 4 replications.
Results and Discussion: In the first experiment application of NAA and BA on in-vitro multiplication of F. imperialis were evaluated. Highest callogenesis and formation (100 %) was observed in mediums contained 0.3 mg/l NAA + 1 mg/l BA, 0.6 mg/l NAA + (0.3, 0.5 and 1 mg/l) BA. Also, callogenesis was obtained in medium contained 0.5 mg/l BA without NAA. This result showed that only in medium supplemented with 1 mg/l BA provided highest (100%) callogenesis, when NAA concentrations were low. However, high levels of NAA (0.6 mg/l) in all concentrations of BA were obtained maximum callogenesis. We concluded that NAA is essential for callogenesis and enhancing its levels can increase callogenesis. Also, application of low levels of BA (0.4 µM) in callogenesis mediums of Cynodon dactylon contained Auxins resulted in increment of embryogenetic calli formation. In the other hand, presence of BA is essential for plantlet regeneration, however NAA is not necessary. Plantlet regeneration was obtained in PGRs free medium. Statistical analysis of results showed that different concentrations of BA and NAA had significant effects on percentage of callogenesis, diameter of calli, percentage of regeneration, length of leaves and roots (P
Research Article
Seied Mehdi Miri; Meysam Salari; Ahmad Ahmadpour
Abstract
Introduction. Citrus is one of the most commercially important horticultural crops grown in tropical and sub-tropical regions of the world. They are classified as non-climacteric fruits. Harvesting date and storage can influence citrus fruit quality and shelf life. In Iran, some members of citrus family ...
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Introduction. Citrus is one of the most commercially important horticultural crops grown in tropical and sub-tropical regions of the world. They are classified as non-climacteric fruits. Harvesting date and storage can influence citrus fruit quality and shelf life. In Iran, some members of citrus family including sweet orange and mandarin are produced as an export crop, so research on fruit quality and storage life is needed. There is no available scientific literature regarding the effect of harvesting date and storage duration on retaining the postharvest physicochemical properties of Kinnow mandarin under cold storage. The main objective of the present study was to evaluate the effect of harvesting date and storing time on shelf life and quality of Kinnow mandarin fruits under Jiroft weather conditions.
Materials and Methods. Investigations were carried out on mandarin (Citrus reticulata) cv. Kinnow grafted on sour orange rootstock in an orchard located in Jiroft and Kahnooj Agricultural Research Center, Jiroft, Iran. Fruits were harvested on 6th December, 21th December, 5th January, 20th January and 4th February. After cold storage for 30-90 days at 4-6 °C, the fruit was analyzed for quantitative and qualitative characteristics including weight of fruit, peel, meat, pulp and juice, fruit weight loss, pH, total soluble solids (TSS), titratable acidity (TA) and TSS/TA. Experiment was arranged in a split plot based on randomized complete block design (RCBD). Data analysis and similarity coefficient (Pearson's method) were performed using SPSS.16 software, and means comparison was performed by using Duncan's multiple range test at 1 and 5% probability levels.
Results and Discussion. The results showed that the interaction effect of harvesting date and storage period on the weight of the fruit, meat, pulp and juice and TSS, TA and TSS/TA was significant at 1% probability level. Weight of harvested fruits from 6th December to 5th January was constant, but fruits harvested on 20th January and 4th February were heavier as much as 12.5 and 14.3 percent, respectively, compared to 6th December. Fruit weight loss increased along with the increase in storage time duration, so that mean fruits weight loss percentages were 3.5 and 16.5 at 30 and 90 days of storage, respectively, due to continued transpiration of the fruits after harvesting. As a result of transpiration, water enters into the atmosphere through the pores existing on fruit surface. The greatest fruit weight (121.8 g) was recorded for combination of harvesting on 20th January and 30-day storage. Fruits harvested on 20th January and 30-day storage had higher meat and pulp weight (89.6 and 52.3 g, respectively) and a significant correlation coefficient was detected between them. Changes of fruit juice pH at different stages of fruit ripening and storage times did not follow a fixed pattern, though pH slightly increased in some cases during storage, which can be due to oxidation of citric acid during storage. The maximum TSS was recorded for harvesting on 5th January and 90-day storage (11.7 °Brix) as well as 4th February and 60- and 90-day storages (11.8 °Brix), while the minimum TSS was observed on 6th December and 30-day storage (8.7 °Brix). The results exhibited that TSS content of fruit juice increased when storage period increased, which was possibly attributed to the hydrolysis of starch and increase in sucrose content. However, increase in TSS during storage is not always directly related to changes in the simple sugar content of fruit. During storage and maturation of the fruits on the tree, TA reduced due to the use of citric acid in respiration. Taste index (TSS/TA) in fruits harvested at full maturity was greater than that in fruits harvested in the fall. Besides, TSS/TA increased during storage, so that the highest and lowest average TSS/TA ratios were related to harvesting on 4th February and 30-day storage as well as 6th December and 30-day storage, respectively. According to the results, fruits did not reach full maturity until 5th January under Jiroft weather conditions.
Conclusion. Postharvest quality and shelf life of Kinnow mandarin fruits were affected by harvesting date and storage duration. Delay in harvest resulted in an increase in fruit weight, TSS and TSS/TA. TSS and TSS/TA were higher when fruits harvested on 4th February. Fruit weight loss increased when the storage period increased.. Overall, 4th February is the best date to harvest Kinnow mandarin fruit in Jiroft.
Research Article
Marjan Diayanat
Abstract
Introduction The presence of broadleaf weeds not only reduces the aesthetic quality of the turfgrass, but more importantly they compete with desired turfgrass for water, nutrients, and light. Weed management after seeding is an important component to successfully establishing a healthy stand of cool ...
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Introduction The presence of broadleaf weeds not only reduces the aesthetic quality of the turfgrass, but more importantly they compete with desired turfgrass for water, nutrients, and light. Weed management after seeding is an important component to successfully establishing a healthy stand of cool season turfgrass. Weed seed germination is a key process because determines both the number of weeds that could potentially emerge and the timing of their appearance in the turfgrass. Temperature is of the most important factor regulating germination of non-dormant seeds in irrigated, annual agroecosystems at the beginning of the growth season where light, nutrients, and moisture are typically not growth limiting. Also prostrate knotweed (Polygonum aviculare L.) and annual sowthistle (Sonchus oleraceus L.) are two annual common broad leaf weeds in cool season turfgrass. Prostrate knotweed is very competitive in infertile and compacted soils and often invades turfgrasses along driveways, sidewalks, and beaten paths across lawns. Annual sowthistle is found in open habitats that include waste areas, turf, and roadsides. The aim of this study was to evaluate different nonlinear regression models to describe response of germination rate to different temperatures in perennial ryegrass (Lolium perenne L.), fescue (Festuca rubra L.), prostrate knotweed and annual sowthistle.
Materials and Methods This experiment was based on completely randomized design with 4 replications at Islamic Azad University in the laboratory of Science Research Branch in 2015. The seeds were treated with different temperatures (2, 5, 10, 15, 20, 25, 30, 35, 40 and 45oC) Twenty five seeds were placed in each petri dish for each species in per replication. Ten milliliters of distilled water were added to each petri dish and the filter papers were regularly moistened to ensure saturation throughout the germination tests. Petri dishes were placed in germinator with 16 hour day, 8 hour night and 60% relative humidity. Seeds were considered germinated when the radicle protruded at least 2 mm from the seed coat. Germinated and rotted seeds were counted and discarded at 24 hour intervals until no germination had occurred over four consecutive days. The germination percentage was obtained by dividing the number of germinated seeds at any time by the total number of seeds germinated multiplied by 100. Data from this experiment were first subjected to analysis of variance and means of treatments were compared using the least significant difference at the 5% level of probability. The following nonlinear regression models were used to quantify the response of the germination rate to temperature and to determine cardinal temperatures.
Results and Discussion The analysis of variance showed that temperature had a significant effect on all seed germination percentage and germination rates. Seed germination percentage and rate increased to a point with increasing the temperature. Germination model based on temperature can be used for the prediction of cardinal temperatures. Cardinal temperatures are required because a portion of the crop model is developed for prediction of the timing of germination. Non-linear regression models have been used to quantitatively describe development rate in many plants. Three regression models (Intersected-lines, Dent-like and Quadratic Polynomial) used to predict germination rate and cardinal temperature. Root mean square of error (RMSE) and R2 adjusted were used to find the appropriate model(s). Intersected-lines model was superior compared to other models in perennial ryegrass, fescue and annual sowthistle and Dent-like model was superior for prostrate knotweed. It was concluded that this model can be used to quantify response of turfgrass and common weeds of turfgrass germination to temperature and to obtain cardinal temperature of germination. Also base, optimum and maximum temperatures were for perennial ryegrass 4.12, 24.66 and 43.27oC; fescue 2.0, 24.86 and 43.48oC ; Prostrate knotweed 2.95, 19.94-22.21 and 44.97oC and annual sowthistle 2.0, 17.77 and 44.86oC, respectively.
Conclusions These results show that fescue germinated earliest among the studied species, because it had the lowest base temperature. In comparison to perennial ryegrass, using turfgrass seed with more fescue seed causes sooner turfgrass establishment and less weed competition. Because of their narrow leaves, young seedlings of prostrate knotweed grow upright and appear at first glance to be grass seedlings. With maturity, most plants grow prostrate, especially with traffic or mowing, so mechanical control of this species in turfgrass is impossible andit could be controlled with pre-emergence herbicide. Pre-emergence herbicides are applied prior to the germination of weeds; thus, predication of timing germination help us in decreasing prostrate knotweed competition with turfgrass and its proper management.
Research Article
Shadi Attar; Gholamhossein Davarynejad; Leila Samiee; Mohammad Moghadam
Abstract
Introduction: Persian walnut (Juglans regia L.), belonging to the Juglandaceae family, has its natural origin in the mountainous regions of central Asia and especially northern forests of Iran. Most walnut genotypes are seedling and sexually reproduced. Conducting studies on the genetic structure of ...
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Introduction: Persian walnut (Juglans regia L.), belonging to the Juglandaceae family, has its natural origin in the mountainous regions of central Asia and especially northern forests of Iran. Most walnut genotypes are seedling and sexually reproduced. Conducting studies on the genetic structure of these genotypes to identify, select and maintain their genetic resources is important. Identifying and collecting local varieties of fruit trees is considered as the first step on the path of breeding programs and lack of information regarding plants genetic characteristics causes the breeding work to be done slowly. Various methods have been used for studying genetic diversity and determining the genetic relationship between European and Asian varieties of walnut and identifying commercial walnut varieties, among which we can mention: Morphologic indices, Alozyme, Isozym, RFLP, RAPD, AFLP and ISSR markers. ISSR molecular marker was used in order to investigate genetic diversity of some genotypes of Persian walnut (Juglans regia L.) in Mashhad orchards. .
Materials and methods: To begin with, about 56 walnut trees from 4 orchards in Mashhad (Esteghlal (1), Golestan (2), Alandasht (3) and Emam Reza (4)) were selected and tagged from 2014 to 2016. In the spring of 2014 with the beginning of trees growth and opening of leaves, a number of leaves from each genotype were collected. After DNA extraction, the quality of samples by agarose gel (1 percentage) and electrophoresis method and quantity of them via spectrophotometer device at 260 and 280 nm wavelengths were determined. First, 24 primers of ISSR marker were prepared and after initial evaluation on 5 random genotypes, 9 primers with high polymorphism and repeatability were selected for further investigation. For PCR reaction, Amplicon kit (code 180 301, made in Denmark) was used. Gel electrophoresis images of primers that produced polymorphic bands with suitable resolution were analyzed manually. After scoring the bands, in which 0 used for showing the absence of a band and 1 showing the presence of a band in each sample, 1 and 0 numbers were changed to matrix by using NTedit software. Genetic similarities of samples were calculated by using NTSYSpc software, SIMQUAL method and DICE similarity coefficient. Dendrogram by cluster analysis was drawn by using UPGMA method. Principle coordinate analysis (PCO) was performed using the NTSYS software and grouping samples were evaluated in a two-dimensional plot.
Results and discussion: Results showed that from 9 primers in total, 118 bands amplified were in 300 to 3000 base pairs, while 29 bands were polymorphic. The number of amplified fragment for each primer was different so that UBC 844 (14 bands) had the highest and UBC 890 (8 bands) had the lowest amplified bands. The average amplified fragments for each primer was 9.83. The percentage of polymorphic in various primers was different. Maximum polymorphism (80%) of the primers was observed in UBC830. In general, according to the percentage of polymorphic bands, low adjustment to any changes in the environment was indicated. This can be used as an indicator to determine the value of diversity and genetic erosion. In genotypes cluster analysis, clustering was performed based on Dice similarity coefficient and UPGMA method, and 10 clusters were formed. ISSR molecular marker somewhat revealed genetic diversity among walnuts genotypes, whereas the genetic diversity was lower than expected. In general, by reviewing the findings in other parts of the world about walnut genetic diversity and comparing them with the results of this study, despite existing high genetic diversity among walnuts in many areas, some reports of low genetic diversity among walnuts populations have been published and unfortunately in recent years these reports has made more attention. Based on the results of several studies reporting low genetic diversity among walnuts, the following factors can be effective in this problem: natural disasters, human impacts such as deforestation and selection and propagation of superior genotypes, and sometimes walnuts self - pollination. In this respect, there is concern that if this trend of decreasing genetic diversity in the walnut population continues, this invaluable crop will be in danger of extinction. So we should think about a remedy. Finally, this investigation can be used as a start for conducting more researches in the region to maintain and manage this valuable crop germplasm and maximize genetic diversity for performing breeding programs in the future.
Research Article
hossein sabourifard; Azim qaesmnezhad; Khodayar hemmati; Aboutaleb hezarjaribi; Mahmoudreza bahrami; Fahimeh nosrati
Abstract
Introduction: One of the most important requirements in planning production and processing of medicinal plants in order to obtain high yield and high-quality is the initial assessment of the physical and chemical properties of soil, which reduces the production cost by avoiding the use of unnecessary ...
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Introduction: One of the most important requirements in planning production and processing of medicinal plants in order to obtain high yield and high-quality is the initial assessment of the physical and chemical properties of soil, which reduces the production cost by avoiding the use of unnecessary soil analysis. Summer savory (Satureja hortensis L.) is one the most widely used medicinal plants that quality index of plant is related to the quantity and the constituent of its essential oil content. Understanding the relations between the quantity and quality of medicinal plants with the very physical and chemical properties of soil is very complex and the estimation of parameters changes of medicinal plants affect by soil quality characteristics is more difficult. Today, with the arrival of multivariable regression models and artificial lattice models in the research, many complex relationships found in nature is understandable. Hence the need for estimation the biomass yield of savory using fast, cheap and with acceptable accuracy is feeling.
Materials and Methods: The present study was performed at the Agricultural Research Station Neyshabur as pot experiment based on a completely randomized design with three replications. Around 53 soil samples were collected from different parts of Neyshabur city, and soil texture, organic matter, pH, salinity, phosphorus, potassium, nitrogen and carbon content were selected as the easily available parameters. Before planting the parameters were measured in laboratory. Approximately 90 days after planting seeds in pots containing soil samples, the sampling of plants was done based on the treatments. For drying, samples were placed for 24 hours in an oven at 40 °C. Finally, the relationship between the biomass yield and easily available soil parameters was determined using artificial neural network by Matlab7.9 software.
Results and Discussion: The results showed that soil variability, is a key element in the management of valuable information on soil properties within a field and valuable information on soil properties within a field nature puts at our disposal. In yield modeling with 10 parameters for 53 soil samples, the best makeup hidden layer with Levenberg-Marquardt algorithm training as a hidden layer, 58 neurons, logsig threshold function for hidden layer and Tansig for the output layer were selected. High values of R2 and low levels of RMSE mentioned the proximity of the forecast data with measurement data and high accuracy of the model in summer savory biomass yield estimation. To obtain the most sensitive parameters, the sensitivity analysis was calculated using no-sensitive coefficient. So that, if the coefficient of a sensitive parameter is more than 1.0, the mentioned parameter, is one of the critical parameters of model. Accordingly, the parameters of organic carbon, nitrogen, phosphorus, organic matter, potassium, pH, salinity, clay, silt and sand respectively were selected as the most sensitive parameters. The addition of input parameters increases the value of R2 and reduces the RMSE during training, validation and test stages. This represents an increasing in the accuracy of model in estimation of biomass yield via increasing the input parameters. Models 1(soil texture) and 2(carbon) are not enough strong for biomass yield estimation. With increasing the experiment from 1 to 2, the potency of the neural network model 3(soil texture + carbon) significantly increased. Thus with an overview, the model No. 3 suggested as an improved model because with the minimum number of imputes produced equal output comparing the models with more inputs.
Conclusions: Based on the obtained results, it seems that with the improvement of artificial neural network models and determining appropriate parameters, results to understanding the soil factors involved in the formation of savory plant biomass and better planning. Till leads to a cheaper and better product. Also, results showed that the artificial neural network has high accuracy in estimating the biomass plant Summer Savory. So that, the 80% of yield variability of the study area, presents by using the data of 10 readily available properties of the soil. Yield biomass of savory, largely depends on the soil texture, organic matter, carbon and the minerals of the soil. Since, this study is the first work to estimate the biomass of medicinal plants using artificial neural network, therefore recommended to use this method to estimate the yield and essential oil of other medicinal plants.
Research Article
E. Aryakia; Hamid Reza Roosta; nahid rahmizade
Abstract
Introduction: Date palm (Phoenix dactylifera L.) is one of the most important fruit species grown in Iran. This plant is mainly grown in the south of the country, where pH of soil is high, resulting in poor nutrient uptake. Furthermore, because of high yield and annual pruning of date palm, large amounts ...
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Introduction: Date palm (Phoenix dactylifera L.) is one of the most important fruit species grown in Iran. This plant is mainly grown in the south of the country, where pH of soil is high, resulting in poor nutrient uptake. Furthermore, because of high yield and annual pruning of date palm, large amounts of macro and micronutrients are removed from soil. So, annual fertilizing should be applied for good performance. Research shows that use of manure alone or in combination with mineral fertilizers improves physico-chemical indices of fruits and leaves of palm trees. Regarding to high nutrition dependency of date palm, it is necessary to evaluate the effect of different fertilizers on physico-chemical indices of its leaf and fruit. The main objectives of this study were thus to evaluate the effect of cow manure, ammonium sulfate and potassium sulfate on physico-chemical indices in fruit and leaf of Mazafati date.
Materials and Methods: This study was conducted in bam zone, Kerman, Iran, in 2011- 2012. The area was located at 28°53′40′′N latitude, 58°37′18′′E longitude and 1050 m above sea level. A factorial experiment in a randomized complete block design was performed during month of March. Factors included ammonium sulfate (0, 500 and 1000 g/tree), potassium sulfate (0, 750 and 1500 g/tree) accompanied by cow manure (5 kg/tree). For leaf and fruit analysis, sampling was performed during month of June. Physico-chemical indices including nitrogen, potassium, iron, chlorophyll a, b and total, carotenoid, fruit weight, fruit diameter, fruit length, TSS and TSS/TA were evaluated. Chlorophyll was measured by using the method of Lichtenthaler (1987). Total soluble solid (TSS) was measured by using refractometer. Statistical analysis was performed using SPSS software and the treatment means were separated by Duncan’s multiple range tests.
Results and Discussion: Results showed that because of supplying nitrogen, sulfur and potassium and their significant effects on noted physico-chemical indices, the highest nitrogen and iron content, photosynthetic pigments of carotenoid and chlorophyll (a and total) of leaf, and fruit weight were obtained in treatments of ammonium sulfate (1000 g/tree) and potassium sulfate (1500 g/tree) combination with cow manure (5 kg/tree). The highest potassium content of leaf, TSS and TSS/TA ratio of fruit were obtained by using ammonium sulfate (500 g/tree) and potassium sulfate (1500 g/tree) in combination with cow manure. The general increase in physico-chemical indices of fruits and leaves of date palm by the application of cow manure plus mineral fertilizer might be due to the increase in the availability of nutrients especially available N, P and K in the soil. In many reports, the effects of mineral fertilizers on nitrogen, potassium and iron content of the plant tissues were discussed. For example, date palm (two cultivars including Zaghloul and Samany) treated by ammonium nitrate and nitrobean (a bio-fertilizer) had the highest amount of leaf nitrogen and potassium. The highest rates of nitrogen, iron and potassium in palm fruit were obtained from cow manure in combination with NPK. Nitrogen, iron and potassium contents of the date and pistachio were increased by using ammonium sulfate fertilizer. Fruit weight, length, diameter and dry weight increased, while fruit moisture content decreased by organic manures either alone or in combination with mineral NPK as compared to the mineral N. Higher fruit TSS was obtained by the application of organic manures alone or in combination with mineral NPK as compared with mineral fertilization alone. Nitrogen concentration can be increased by using nitrogen fertilizer, for example ammonium increased leaf nitrogen concentration more than nitrate. Mineral nutrient, especially sulfur and nitrogen supplied by ammonium sulphate and potassium sulphate, increased the content of chlorophyll and carotenoid due to their roles in the synthesis of these compounds. Higher potassium content of leaves promotes photosynthetic rate of chloroplast, phloem transport of photosynthates to sink tissues and finally improves quality and yield of the fruit, which is associated with high sugar content.
Conclusions: For feeding of date palm tree, cow manure fertilization alone is insufficient. Ammonium sulfate and potassium sulfate alone or in combination with cow manure could improve physico-chemical indices of leaves and fruits. This mixed fertilizer, supplying nitrogen, potassium and sulfur macronutrients, had significant effect on physico-chemical parameters, and subsequently improved the content of nitrogen, iron, potassium, photosynthetic pigments (a, b and total, carotenoid), TSS, TSS/TA ratio and the fruit weight.
Research Article
marzieh nourashrafeddin; mohammad farsi; farajolah shahriari; javad janpoor
Abstract
Introduction: Edible white button mushroom (Agaricusbisporus) is the most common edible mushroom in Iran and the world. The yield of this mushroom is less than the average of yield in the world because of strain degeneration and using strains with low yield. Most of the current hybrids are either identical ...
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Introduction: Edible white button mushroom (Agaricusbisporus) is the most common edible mushroom in Iran and the world. The yield of this mushroom is less than the average of yield in the world because of strain degeneration and using strains with low yield. Most of the current hybrids are either identical or very similar to the first hybrids. Ongoing breeding programs are exploiting the variability in Agaricus germplasm to produce new varieties with better traits including higher yield and resistance to biotic and abiotic stresses. One of the breeding programs is F1 production from parental homokaryons crossing. These homokaryonsis were isolated among germinated basidiospores on the culture media. During the last decades, various molecular markers based on nucleic acid polymorphisms (such as Restriction Fragment Length Polymorphism, Random Amplification of Polymorphic DNA, Amplified fragment of Length Polymorphism, Inter Simple Sequence Repeat, Simple Sequence Repeat markers) have been used to differentiate homokaryons and heterokaryons. Microsatellites consist of short tandem repeat motifs distributed throughout the genome. Microsatellites are usually highly polymorphic due to a high degree of variation in the number of repeats among individuals. Microsatellite markers are multiallelic and co-dominant and thus tend to be more informative than other marker systems. Microsatellite markers have been widely developed in animals and plants and more recently in fungal species. The presence of microsatellites in the genome of A. bisporus was previously reported.
Materials and Methods: In this research, 160 germinated basidiospores were collected from commercially cultivated strain A15 and they were grown on compost extract agar (CEA). The mycelial growth rate of these160 isolates was evaluated at 25°C on CEA medium. 18 isolates with slow growing rate were selected from 160 isolates. In the next step, co-dominant SSR markers were used to homokaryons detection. Ten SSR primers showed polymorphism in parental control samples that were used to this experiment. The isolates were divided into two general homoallelic and heteroallelic groups and seven isolates from homoallellic group, which showed one-band pattern, characterized as putative homokaryon. Genetic similarity was calculated by NTSYSpc software version 2.02 e using UPGMA method. In the next step of experiment, the isolates (4 and 8) had minimum genetic similarity that was crossed to produce hybrid. In order to confirm the hybrid formation, PCR-SSR reaction with a primer (AbSSR 45) was performed.
Results and Discussions: Basidiospores were collected and allowed to germinate on CEA medium. Putative homokaryons were different in colony morphology and growth rate compared to the original heterokaryons. Mycelium samples showed different colony morphology including tomentose, apprised and strandy mycelium. Different growth rate can be affected by genetic factors in nucleus and mitoconderia. After four weeks, mycelium browning was appeared in liquid compost extract medium and created a disturbance in DNA extraction. To solve this problem, DNA was extracted from three-week old mycelium. Mycelium browning may cause by phenolic compounds produced by mycelium and enzymes that catalyze melanin biosynthesis reactions. Ten primers were used to homokaryon isolation. These primers were situated on the 9 linkage groups of 13 haploid chromosomes. Seven isolates were distinguished as putative homokaryon that showed one-band in all primers on the gel electrophoresis. The results of genetic similarity calculation showed that this index was variable between 0.17 to 0.67in 7 homokaryon isolates and the minimum genetic similarity (0.17) was observed between isolates 4 and 8. These two isolates were crossed and the result of this crossing was N1 hybrid. Also, other homokaryon isolates were crossed and mating incompatibility was observed in some of them. According to these observations, it is suggested that in future studies, in addition to genetic similarity, sexual incompatibility should also be considered. Hybrid N1 produced aerial mycelium and had higher growth rate in comparison to parental homokaryons and similar to heterokaryon control, had two-bands pattern. This two bands pattern indicates the presence of two non-sister nucleuse in each cells. Finally, the results showed that SSR marker can result to accurate detection of homokaryons.
Conclusions: The aim of the present study was screening homokaryon isolates of A.bisporus using SSR markers to obtain hybrid. Results showed that growth rate of homokaryon isolates were lower than the heterokaryons. Since, SSR markers were able to show high polymorphism in the isolates, thus it can be said that these markers are suitable to homokaryon screening. Final result of this study is N1 hybrid that can compare to commercially cultivated strains.
Research Article
hajar shayesteh; Saeid Malekzadeh Shafaroudi; kamal ghous; farajolah shahriari
Abstract
Introduction Jujube (Zizyphus jujuba Mill.) as a valuable medicinal plant and adapted to different climatic conditions is widespread in many parts of Iran. Nowadays, beside the export of its fruit, jujube is also used as an herbal medicine to treat the diseases, so it has a high economic value. Study ...
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Introduction Jujube (Zizyphus jujuba Mill.) as a valuable medicinal plant and adapted to different climatic conditions is widespread in many parts of Iran. Nowadays, beside the export of its fruit, jujube is also used as an herbal medicine to treat the diseases, so it has a high economic value. Study on genetic diversity is the first step to identify and preservation of germplasm. It is also considered as the basic principles of plant breeding. DNA markers seem to be the best way in determination of the genetic diversity. Inter simple sequence repeats (ISSR) markers are highly polymorphic and combine most benefits of Simple Sequence Repeats (SSRs) and amplified fragment length polymorphism (AFLP) to the generality of random amplified polymorphic DNA (RAPD).
Materials and Methods In order to study of the genetic diversity among 31 ecotypes collected from eight Jujube-rich provinces, including South Khorasan, Razavi Khorasan, Mazandaran, Golestan, Qom, Isfahan, Lorestan and Fars. Genomic DNA was extracted by CTAB method and polymerase chain reaction (PCR) was performed with 13 ISSR primers in which six most efficient primers were selected. Cluster analysis based on Dice similarity coefficient and Unweighed Pair Group Method with Arithmetic Mean (UPGMA) was carried out and POPGENe.3.2 software was used to determine the similarity of populations with each other.
Results and Discussion 84 loci were amplified and 70 of them (83%) revealed a proper polymorphism with the size between 200 and 2000 base pair. The average number of amplified and polymorphic bands per primer was 14 and 11.6 respectively. Primers with di-nucleotide repeats produced more polymorphic bands than ones with tri-nucleotide repeats. It seems that this is due to a higher frequency of sequences containing di-nucleotide repeats in intergenic regions and higher possibility of mutation revealed in more diversity in comparison to gene coding regions. Anchored primers with 1 or 2 nucleotides at the 5’ end make sure annealing only to the ends of SSRs in template DNA, so avoiding internal priming and smear formation. In addition, the anchor lets only a subset of the microsatellites to serve as priming sites. Primers (AC)8YT and (GA)8A with the higher percentage of polymorphism is recommended for further analysis. According to the cluster analysis, the ecotypes could be classified into seven main groups at the 0.85 level of genetic similarity. The most genetic similarity (0.95) was observed between ecotypes from Kalaleh and Doroh and also Noghab and Dustiran and the least genetic similarity (0.48) observed between Kangan and Borzaderan. POPGENe.3.2 software data indicated that populations of Isfahan and South Khorasan had the slightest difference while populations of Isfahan and Razavi Khorasan showed the most difference.
Conclusions In general results demonstrated that the total diversity of jujube ecotypes in Iran is summarized in the area of South Khorasan province. Given data showed that South Khorasan has been an original place of cultivation of this medicinal plant, this area could be considered as one of the important centers of jujube diversity. In addition, significant levels of diversity were observed among ecotypes belonging to Isfahan and Mazandaran provinces.
Research Article
zahra shabani; Bahram Abedi; Abrahim Gangimoghadam; Ali Tehranifar
Abstract
Introduction: This study was conducted aimed to consider the effects of culture medium and the concentration of growth regulators on proliferation, rooting and the acclimatization of Myrobalan29C. This study was performed as a factorial experiment in a completely randomized design (CRD) with four replications ...
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Introduction: This study was conducted aimed to consider the effects of culture medium and the concentration of growth regulators on proliferation, rooting and the acclimatization of Myrobalan29C. This study was performed as a factorial experiment in a completely randomized design (CRD) with four replications where each plot contained five explants. Given the role of trees rootstock of growth rate vegetative in the early maturity٫ yield and disease resistance will be suitable rootstock that has an important role in program garden management. In total rootstock of fruit trees have be propagation sexual and asexual methods, however٫ given that in sexual reproduction the resulting dispersion characteristics and the resulting seedlings changed by genetics, it is tried for decades to asexual propagation methods in specially tissue culture methods healthy rootstock for mass propagation and used the development of orchards. Seedling rootstock Myrobalan had been used in the past. The rootstock can be positive features cited the ease of access, to be cheap, good yields after maturity. In study, the effects of NAA and BAP on proliferation of Gisala5 rootstock showed the most shoot treated in mediacontaining 1mg/l BAP. Investigated Chinese plum in vitro micropropagation showed that 1/2 MS media had the highest percentage rooting, and acclimatization rooted plantlets to greenhouse conditions was using the system miss successfully. Due to the importance and essential to achieve an efficient protocol for the mass propagation of Myrobalan 29C in Iran, this study was conducted with the main purpose of evaluating the most suitable media culture and plant growth regulators in micropropagation of Myrobalan 29C.
Material and methods: The explants were collected from shoots of Myrobalan 29C rootstock maintained in the experimental greenhouse of Khorasan Razavi Agricultural and Natural Resources Research Centre (of Mashhad, Iran), on June 25, 2013. The explants were washed by water and dishwashing liquid to removed surface contamination. Then they were divided to some parts containing one bud and were sterilized with ethanol 70% 1 min and sodium hypochlorite 10% at 10 min. Proliferation was performed in two kind of culture medium (MS and DKW) that supplemented with plant growth regulators BAP (0, 1, 2, 3, 4 mg l-1). The rootstocks of in this step, after subculture three (21 days between each subculture), the numbers, the length and quality of the shoots (explants strong growth, with no signs of vitrification, necrosis of leaf are yellowing terminal meristem), b– less than 15% have the symptoms of vitrification, necrosis of leaf are yellowing terminal meristem, and c– explant weak, 15-30% have the symptoms of vitrification, necrosis of leaf are yellowing Terminal meristem) were measured. This stage was carried with four replications and each replicates with five samples. Two culture media (MS and DKW) were used for rooting, which supplemented with indole-3-butyric acid (IBA) at four levels (0, 1, 2, 3 mg l-1). This stage was carried with four replications and each replicates with three samples. After being rooted explants, the best cultured media and combination of rooting growth regulators number and root length, leaf number and stem length and quality of explants were recorded. Acclimatization used in substrate including Coco Peat - Perlite 3:0/5 V, Coco Peat 100%V٫ Coco Peat - Perlite 0.5:3V, Perlite100%V and Coco Peat - Perlite1:1V).
Results and Discussions: Results showed that the 10% sodium hypochlorite for 10 min, with 4% decay was the best treatment for sterilization. The results showed that the proliferation average was 6/16 in MS medium with 2 mgl-1 BAP and the most percent of rooting and root length were about 100% and 2/51 cm in MS medium with 2mgl-1 of IBA, respectively. The acclimatization of plantlets to greenhouse conditions was successful. The highest rate of plantlets survival (about 70%) was obtained from substrate Cocopit and Prlit (1; 1 V). In the present study, explants year compared annual explant least contamination had enjoyed. It seems that the young explants, smooth the surface of the skin, having the least amount of crack depend on the type of surface depressions explants and the crack and lower depressions the surface explants increase surface contact area disinfectants and also improve its impact. In this study found that the type of medium a significant impacted on the health of plants and so the proliferation of explants was successful. Usually root production in plants under the influence of synthesis, metabolism, and transport is auxin signaling pathways. Therefore acclimatization directly affected the rooting of plants that had high quality and the best rate of induction.
Conclusions: The results of this research showed that we can duplicate Myrobalan29c rootstock by in vitro method. According in this research, MS media including BAP and IBA plant growth regulators are the most suitable for micro propagation.
