Pomology
N. Soukht saraei; F. Varasteh; M. Alizadeh
Abstract
Introduction
In recent years, the use of organic acids has increased due to their role in the quantitative and qualitative yield and resistance to environmental stresses. Ascorbic acid (vitamin C) is one of the important antioxidants and plays a role as the primary substrate in cyclic pathways to remove ...
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Introduction
In recent years, the use of organic acids has increased due to their role in the quantitative and qualitative yield and resistance to environmental stresses. Ascorbic acid (vitamin C) is one of the important antioxidants and plays a role as the primary substrate in cyclic pathways to remove toxicity and neutralize superoxide and single oxygen radicals. Ascorbate is also involved in the regulation of cell division and photosynthesis and has nutritional value for humans and is probably important for the tolerance of plants against photo-oxidative stress. Oxalic acid is a metabolic end product in plants that has many physiological functions, the main ones is the induction of resistance to disease and environmental stress by increasing the activity of enzymes involved in resistance and secondary metabolites such as phenol, flavonoid, etc. Considering the importance of the physiological traits of the plant in the production of quantitative and qualitative yield of strawberry and on the other hand, the lack of sufficient information about the effect of external application of ascorbic acid and oxalic acid on the physiological traits of the plant, the present research work aimed to investigate some physiological and qualitative traits of strawberry leaves and fruits affected by foliar spraying of ascorbic acid and oxalic acid.
Materials and Methods
The experiment was conducted based on randomized complete block design (RCBD) with three replications in Darkalate village of Ramiyan city of Golestan province to investigate some physiological responses of strawberry cv. Camarosa to the foliar application of organic acids. The experimental treatments consisted of three levels: non-spraying as control, spraying with 1 mM ascorbic acid and 1 mM oxalic acid, which was performed in three stages (from end flowering stage to the green fruit stage) at 6 days intervals. Finally, three plants were selected from each experimental unit and leaf samples were taken and transferred to the laboratory to measure physiological traits i.e. leaf area, fresh and dry weights, total chlorophylls, chlorophyll a and chlorophyll b, total carotenoids, total sugars, total phenols and flavonoids. Also, when at least 75 percent of the fruit surface turned red, the fruits were harvested from each plot separately and immediately transferred to the Plant Physiology Laboratory of Gorgan University of Agricultural Sciences and Natural Resources. The physicochemical traits of strawberry fruits including total soluble solids (TSS), titratable acidity (TA), flavor index, vitamin C, total phenol, flavonoid, antioxidant activity, total anthocyanins were measured. Analysis of data were performed using SAS 9.2 statistical software and comparison of mean data were undertaken based on LSD statistical test.
Results and discussion
The results showed that the foliar application of ascorbic acid and organic acid had a significant effect on the leaf area, fresh and dry weights, total chlorophylls, chlorophyll a, chlorophyll b, carotenoids, total sugars, phenols and flavonoids. The highest mean leaf area (314.08 cm2), leaf fresh and dry weights (1.78 and 0.56 grams, respectively), chlorophyll a (0.43 mg/g), total carotenoids (0.29 mg/g), total sugars (1.43 µg/g), total phenols (0.70 mg/g) and flavonoids (0.19 mg/g) were observed in the application of oxalic acid. The control had the lowest mean in all studied traits (except carotenoids). The application of both ascorbic acid and oxalic acid resulted in an increase in photosynthetic pigments, elevating the total chlorophyll content by an average of 22% compared to the control group. Additionally, foliar spraying with ascorbic and oxalic acid led to higher levels of total soluble solids, increased antioxidant activity, and enhanced total flavonoid content in the fruit compared to the control group.Moreover, fruits harvested from plants treated with oxalic acid before harvest exhibited higher levels of total anthocyanin and phenol compared to fruits from plants treated with ascorbic acid before harvest and the control group. Fruits of plants treated with ascorbic acid compared to plants treated with oxalic acid had lower vitamin C and titratable acidity and higher flavor index. The physiological influence of oxalic acid was more superior than that of ascorbic acid and had higher positive effects in the studied traits were recorded. However, since ascorbate is one of the precursors of oxalic acid biosynthesis. Therefore, the changes caused by oxalic acid are indirectly influenced by ascorbic acid. Ascorbic acid acts as a cofactor in photosynthetic reactions and prevents the destruction of chlorophylls and carotenoids due to its antioxidant property, and by interfering in cell division and increasing the surface area of leaves; it increases photosynthesis and the production of carbohydrates. In general, according to the results, it was found that the application of ascorbic acid and oxalic acid improved the quality characteristics and the content of health related compounds of Camarosa strawberry fruit by increasing photosynthetic pigments and biomass.
Growing vegetables
Z. Toosi; S.J. Mousavizadeh; K. Mashayekhi; M. Alizade
Abstract
Introduction Asparagus, scientifically named Asparagus officinalis. L is a perennial plant belonging to the Asparagaceae family. Asparagus is a large genus in this genus that has about 200 species. The most important species for agricultural purposes is A. officinalis. Somatic embryogenesis is the ...
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Introduction Asparagus, scientifically named Asparagus officinalis. L is a perennial plant belonging to the Asparagaceae family. Asparagus is a large genus in this genus that has about 200 species. The most important species for agricultural purposes is A. officinalis. Somatic embryogenesis is the formation of an embryo from an-asexual cell in vitro that similar to a seed embryo, is able to develop into a complete seedling. Somatic embryogenesis is a complex molecular and biochemical process based on cellular potentiogenicity and a model in the study of plant growth. In this unique process of embryogenesis, the growth cells acquire the capacity for embryogenesis under conditions of cellular stress. Sucrose is the predominant sugar in plants for energy production and facilitates vital functions. Sucrose is converted to glucose and glucose. Sucrose is the most common source of carbohydrates used in plant tissue culture.Materials and Methods The present study was performed in the tissue culture laboratory of the horticulture department of Gorgan University of Agricultural Sciences and Natural Resources in 1399 and 1400. Native Iranian asparagus seeds with octaploid ploidy level were used in this experiment. B5 medium containing 2, 4-D with a concentration of 2 mg /l was used to induce the embryo. Concentrations of 3, 6, 9, 12 and 15% in liquid medium were used to evaluate the effect of sucrose. The pH of the culture media were adjusted to 5.7. After the induction phase, the samples entered the realization phase and the subculture were cultured in the previous environments but with the aim of emerging the embryos (realization phase) while the hormone was removed from them. After 4 weeks in the embryonic development stage, the number of globular and bipolar embryos was observed using a computer-connected stereoscope at 20 and 40 micron magnifications.Results and DiscussionThe results obtained from this study showed that there is a significant difference between different concentrations of sucrose in terms of embryogenesis formation at different stages of embryogenesis. According to the presented results, change in sucrose concentration caused a change in the formation of embryos and the highest number of spherical embryos was observed with a significant difference (p <0.001) in 9% sucrose concentration. According to the comparison results, the concentration of 9% sucrose showed the highest amount of bipolar embryo among other different concentrations. Statistical results of photosynthetic pigments and anthocyanins showed that there was a significant difference between different concentrations of sucrose. As shown in Figures 2 and 3, the highest levels of chlorophyll a, b, total and carotenoids were observed at a concentration of 9% sucrose and the lowest amount of chlorophyll a at concentration of 12% and total chlorophyll and carotenoids at concentration of 3%. Also, the results obtained from regression analysis showed that the highest amount of photosynthetic pigments and starch was observed in 9% sucrose concentration. Finally, in this study, it was found that the best concentration affecting the vegetative embryogenesis of octaploid asparagus is 9% sucrose. Conclusion Carbohydrates are the main constituents of the plant and are most used in tissue culture medium, especially sucrose for growth and differentiation. It is noteworthy that high concentrations of sucrose are not only nutritional but also change the osmotic pressure in the culture medium. The relationship between glucose status and embryonic formation has been proven. In the meantime, the capacity of sucrose to support embryonic growth is greater, so that increasing sugars such as sucrose increase the potential for embryogenesis. According to the results of the present study, 9% sucrose in B5 culture medium showed an important role in chlorophyll production and caused photosynthesis and carbohydrate metabolism in this medium to increase, and as a result, the amount of sugar and its accumulation in culture explants. Increased in this medium and eventually caused the emergence of embryos with photosynthetic pigments in the resulting seedlings. Increasing the level of sucrose also prevents rapid germination and helps the development of the root system.
F. Moayedi; S. Kordi; A. A. Mehrabi; S. Dastborhan
Abstract
Introduction: Sweet basil (Ocimum basilicum L.) is one of the oldest spices belongs to the Lamiaceae family. It is a herbaceous annual plant, which is native to subtropical regions of Asia, Africa, America. Basil is an important economic crop and widely used in the culinary arts, food processing and ...
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Introduction: Sweet basil (Ocimum basilicum L.) is one of the oldest spices belongs to the Lamiaceae family. It is a herbaceous annual plant, which is native to subtropical regions of Asia, Africa, America. Basil is an important economic crop and widely used in the culinary arts, food processing and pharmaceutical industries. Nitrogen is one of the most important nutrients for plant production that plays a major role in photosynthetic activities and crop yield capacity and its availability affects plants growth and biochemical processes. Nitrogen deficiency is often a limiting factor in vegetable production such as sweet basil. Nitrogen usage significantly can be increased the herb yield of basil grown in different environmental conditions. The nutritional and environmental factors are the most important factors for growth of the medicinal plants. In the present research, changes in yield, nitrate content, essential oil yield and some physiological traits have been investigated in four cultivars of sweet basil under different levels of nitrogen.
Materials and Methods: A field experiment was carried out in the Agricultural Research Station of Khorramabad during 2016 growing season. The experimental factors were arranged as a factorial-split-plot in time experiment based on randomized complete blocks design with three replications. Experimental factors were cultivars of sweet basil (O.basilicum var Italian Large Leaf، O. basilicum var Mobarakeh, O. basilicum var Sweet Thai and O. basilicum var Cinnamon) and nitrogen fertilizer (0, 100 and 200 kg ha-1 urea) assigned to the main plots as factorial and different cuttings (three harvests from each plot) considered as sub-plots. The half amount of nitrogen (as urea; 46% N) was distributed in experimental plots before planting the seeds and the rest used after the first harvest. Seeds of sweet basil were planted at May, 25th 2016 as five rows with 2m length and each main plot area was 5 m2. The space between rows was 50 cm. All plots were irrigated immediately after sowing. Subsequent irrigations were carried out every four days. The control of weeds conducted manually during the experiment time. The sweet basil plants were harvested three times in early flowering stage in July 12, August 15 and September 25. Samples of 1 m length were taken from the center of two rows located in the middle of each plot. Plants were cut from above ground and transferred to the lab for measuring total dry yield. The measured traits in this study included branches per plant, inflorescences per plant, plant height, leaf percentage, total dry yield, essential oil yield, chlorophyll a, chlorophyll b, total chlorophyll, carotenoid and nitrate content. SAS (version 9.1) and MSTAT-C statistical software were used to conduct analysis of variance (ANOVA) and comparison of means, respectively. The Duncan's multiple range test, at 5% probability level, was used to rank the differences among means.
Results and Discussion: The results indicated that the application of nitrogen fertilizer significantly improved all the studied traits. The highest and the lowest essential oil yield belonged to 100 kg ha-1 urea and control, respectively. Nitrogen fertilizer by providing the nitrogen needed for the basil plant during the growing season provides a favorable environment for the production of further biomass. Total dry weight of the all basil cultivars increased with application of nitrogen fertilizer in all harvests. The highest total dry weight and nitrate concentrations were achieved by Italian largel cultivar with application of 200 kg ha-1 urea in the second harvest. The increment in total dry weight of basil by application of nitrogen fertilizer could be attributed to the increment in chlorophyll content and better growth of plants and subsequently the better canopy development which ultimately leads to the better usage of solar irradiance, higher photosynthesis and finally higher dry weight in basil plants. Application of nitrogen chemical fertilizer could increase essential oil yield of sweet basil, mainly due to the increasing of total dry weight.
Among basil cultivars, Italian large leaf cultivar had the highest leaf percentage and essential oil yield compared to the other cultivars. The lowest number of branches per plant, number of inflorescences per plant, leaf percentage, essential oil yield and total chlorophyll belonged to Mobarakeh cultivar. All the evaluated parameters were lower than the first harvest except leaf percentage and chlorophyll content.
Conclusion: According to the results, application of nitrogen fertilizer had a positive effect on growth, and consequently led to increase the plant vegetative yield. Due to the fact that in terms of more of the studied traits there was no significant difference between application of 100 and 200 kg ha-1 urea fertilizer and also reduce the consumption of chemical fertilizers generating pollution, Italian large leaf cultivar and application of 100 kg ha-1 urea are recommended to access an acceptable growth and quantitative and qualitative yield in sweet basil under the environmental conditions similar to Khorramabad.
N. Gharaei Masjedi; M.H. Shamshiri; M.R. Dehghani
Abstract
Introduction: Pistachio (Pistacia vera), as one of the most important horticultural products of Iran, has been embraced as one of the main commercial products. Rafsanjan is an important area of pistachio production in the world. High production is primarily dependent on the ability of the trees to produce ...
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Introduction: Pistachio (Pistacia vera), as one of the most important horticultural products of Iran, has been embraced as one of the main commercial products. Rafsanjan is an important area of pistachio production in the world. High production is primarily dependent on the ability of the trees to produce large amounts of photoassimilates during the growing season. Nitrogen is the primary nutrient element needed in the greatest quantities for plant growth and physiology. The greatest impact of nitrogen is in relation to photosynthesis. Therefore, the rate of CO2 assimilation has been closely related to leaf nitrogen status. Nitrogen deficiency leads to the reduction in the activities of enzymes involved in photosynthesis and consequently a decrease in the rate of CO2 assimilation. Regarding the key role of nitrogen in metabolic activities, especially photosynthesis, this research was conducted to investigate the effects of repeated foliar applications of urea on photosynthesis parameters of “Kalleh-ghuchi” pistachio cultivar.
Materials and Methods: This research was conducted to assess the effect of repeated foliar applications of urea on photosynthetic parameters of pistachio trees in different stages of fruit growth, as a factorial experiment based on a randomized complete block design with five replications. In this experiment, urea was applied at the rate of 0.5% at three different stages of fruit growth including initiation of embryo growth, rapid growth of embryo and during flower bud abscission with two weeks interval. Measurement of photosynthesis parameters (including photosynthesis (A), transpiration rate (E) and stomatal conductance (gs) and intercellular CO2 concentration (Ci)) were done by used a portable photosynthesis system, after measuring photosynthesis parameters, chlorophyll fluorescence parameters (Fv/Fm and PII) were recorded by using a Chlorophyll Fluorometer. Leaf nitrogen content was determined by the kjeldahl method. Leaf chlorophyll and carotenoids content were measured according to porra (2002). Photosynthetic nitrogen use efficiency (PNUE) was calculated as the ratio of photosynthesis to foliar nitrogen content. All above parameters was performed in two times, one day after the last spraying and 10 days after the first stage of measurement. The experimental data was analyzed by SAS software and the significant differences among the treatment were tested by Duncan test.
Results: The results showed that photosynthesis and transpiration rate and stomatal conductance were increased in urea treated trees compared to control in both sampling dates, while intercellular CO2 concentration was decreased by urea application. Three times applications of urea caused a 20% increase in photosynthesis rate compared to control trees. Leaf nitrogen content was also increased by repeated urea application in two sampling dates, as three times application of urea resulted in a 65% increase in leaf nitrogen concentration compared to the control , while photosynthetic nitrogen use efficiency decreased by urea application. Fv/Fm and PII were improved by repeated urea applications in two sampling dates. The results also indicated that chlorophyll pigments were increased by urea application. Generally, results showed that the maximum of photosynthesis and related parameters were obtained with three applications of urea at second date of sampling.
Discussion: Any increase in photosynthesis with urea application indicates that more nitrogen maybe allocated to the enzymes of the carbon assimilation. Thus, more CO2 could be used by the plant, therefore increases in CO2 assimilation was accompanied by a decrease in the Ci due to nitrogen application. In the present study, nitrogen application increased stomatal conductance of pistachio trees. Application of nitrogen can influence stomatal opening, and thus transpiration rate. Increased chlorophyll content with applied nitrogen indicates paramount role of nitrogen in determining of chlorophyll synthesis. Increasing photosynthesis rate is always accompany with chlorophyll fluorescence reduction that is in agree with our results. Differences in PNUE are mainly brought about by differences in photosynthetic capacity or foliar nitrogen allocation either within the photosynthetic apparatus or to non-photosynthetic pools (e.g. cell walls, nitrate).
Conclusion: The results of this study showed that urea application can improve photosynthesis capacity by increasing nitrogen content of pistachio leaves. In this experiment, repeated foliar applications of urea in different stages of fruit growth had positive effects on photosynthesis and other dependent parameters which may be effective in reduction of alternate bearing in pistachio trees. On the other hand, the effect of nitrogen application on photosynthesis was continued for more than a month after application, compared to control.
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.
fateme hasanvand; abdolhossein rezaei nejad; mohamad feizian
Abstract
Introduction: Scented geranium (Pelargonium graveolens) is a perennial plant of the family Geranium (Geraniaceae). Although CaCl2 at higher concentrations than NaCl in the soils and ground water in many areas of the word, most studies have been based on experiments that NaCl is the predominant salt. ...
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Introduction: Scented geranium (Pelargonium graveolens) is a perennial plant of the family Geranium (Geraniaceae). Although CaCl2 at higher concentrations than NaCl in the soils and ground water in many areas of the word, most studies have been based on experiments that NaCl is the predominant salt. Relatively few studies have focused on the effects of CaCl2 on plant growth and physiology. Silicon (Si) is considered as an essential element in several crops enhancing growth and alleviating different biotic and abiotic stresses. In this study, the role of Si in alleviation the deleterious effects of salinity on geranium have been studied.
Materials and Methods: This experiment was conducted in spring-summer 2014 in research greenhouse situated on the Faculty of Agriculture, Lorestan University, Khorramabad, Iran. The greenhouse temperature was 16.5–37.5 ◦C and relative humidity of greenhouse was 30–80%. Terminal stem cuttings with five nodes were obtained from mother plants in the same greenhouse and placed in a sand substrate for rooting in April. Uniform rooted cuttings were then transplanted into plastic pots (22 cm diameter and height) filled with sand substrates and grown hydroponically. Transplanting was done in May and one plant per pot was cultivated. Cultivated plants were irrigated with Hoagland’s medium electrical conductivity (EC) 1.8 dS/m, (pH) 5.8 twice a day. Experiment was arranged as factorial based on a completely randomized design with five replications. Factors consisted of daily application of 1.8, 4 and 6 ds/m CaCl2 and weekly application of 0, 0.5 and 1 mM silicic acid in nutrient solution. Plants were harvested in November. In this research some characteristics include the number of leaf, leaf area, photosynthetic pigments (chla, chlb. Total chl, carotenoids), MDA, EL, RWC, proline, number of stomata in surface unit of leaf, density of stomata and stomata index and antioxidant enzyme include CAT and POD measured.
Results and Discussion: In current study salinity decreased the number of leaf and leaf area and Si increased these characteristics. In general, decrease in the leaf area can result in a reduction in size of individual leaf of plants, decrease in the production of leaves and fall the old leaves. It also reduce the growth rate of leaf in salinity which causes osmotic effect around the roots (rhizosphere). Over time, the rate of cell division and elongation decreased, and finally this changes leads to decrease in the final size of leaf. In this study, salinity increased electrolyte leakage and the use of silicic acid prevents electrolyte leakage. Probably saturation of phospholipids with increasing salinity increased, as a result the fluidity of membrane decreased and finally increased the electrolyte leakage, silicic acid absorbed in plant and deposited in the cell membrane, causing the silica hardened. This causes in stress condition, cell membrane maintains stability and significantly reduced the amount of electrolyte leakage. In this study application Si in various concentrations under salinity stress brought a significant decrease in MDA compared with salinity alone. Salinity increased the MDA and EL so that application of1 mM silicic acid decreased EL to 16.7 and 11.9 percent plants grown in 4 and 6 dS/m EC, respectively, compared with controls. Application of 1 mM silicic acid decreased the MDA to 23.6 and 35 percent plants grown in 4 and 6 dS/m EC, respectively, compared with controls. Therefore, the present results indicate that Si can effectively ameliorate membrane lipid peroxidation, thus protecting plants from oxidative stress. Salinity affected on leaf anatomy and chloroplast ultrastructure, photosynthesis also affected by these factors. Reduction in chlorophyll at height salinity levels due to chloroplast destructive. The results showed that salinity decreased the density and stomatal index in plants and silicic acid increased these characteristics. Salinity decreased the RWC and antioxidant enzymes and application of silicic acid improved them. Increase in salinity increased the leaf proline and application of silicic acid alone in plant on stress decreased it.
Conclusion: Overall, the results of present research showed that high EC induced by CaCl2 negatively affected geranium growth, and weekly application of 1 mM silicic acid alleviated the destructive effects of stress and in high salinity the positive effect of silicic acid is more than in low salinity.
ali salehi sardoei; parviz rahbarian
Abstract
Introduction: One factor that is of great importance to the cultivation of flowers and ornamental plants, is the media. Planting plants in containers as an important component of the nursery technology has grown. Compared with farm volume, growth media used for each plant greatly reduce plant growth ...
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Introduction: One factor that is of great importance to the cultivation of flowers and ornamental plants, is the media. Planting plants in containers as an important component of the nursery technology has grown. Compared with farm volume, growth media used for each plant greatly reduce plant growth that largely influence by the physical and chemical properties of growth media used. Therefore, good management of potted plants bed will cause the plants have good quality. A good growth media with optimal physical and biological properties, relatively inexpensive, stable and style enough to work should be available. The Burgers showed that composted green waste can be used as substrates for soilless cultivation and improve the water-holding capacity of soil. The garden has a range of materials including hardwood and softwood bark, leaves, soil, waste, sewage sludge and coconut (cocopeat) that has been used as a seed bed. According to the economic issues and increasing moisture storage, palm peat substrates are primary material that can be prepared as a good growth medium for the producing's presented level Country. Peat moss is not applicable to all plants because of high cost and poor absorption characteristics like low pH and low water holding capacity . This study was conducted to investigate the possibility of replacing peat moss palm waste and the effect of it on growth characteristics were studied.
Materials and Methods: The experimental design was completely randomized design with four replications of eight treatments. The compressed unit (block) was supplied and commercial cocopeat was used because of reducing the cost of transportation. Before applying this material, the amount of water was added for opening up and voluminous and become it completely uniform.. In treatments containing sand + perlite, these four types volume ratio of 1:1 and mixed with sand + perlite were used. First, wooden cuttings of pandanus in a bed of sand rooted in the greenhouse, then the rooted cuttings were transferred to pots with a diameter of 17cm. The pots were filled with the examined material. After planting in pots in a greenhouse with temperature of 20-25°C in winter and 30-35°C in summer were kept on planting plans. The indicators of growth including stem diameter, stem length and lateral shoot number, leaf area and chlorophyll index were measured. Analysis was performed on data using SPSS 16. Comparisons were made using one-way analysis of variance (ANOVA) and Duncan’s multiple range tests. Differences were considered to be significant at P < 0.05.
Results and Discussion: Vegetative characteristics of pandanus plants were significantly different from each other. Results showed that the mean media of cococheps and 50% peat palm + 25% sand + 25% perlite had the highest leaf area with 413.97 and 378.69cm2 respectively and non-significant difference was showed. Means followed by same letter are not significantly different at P
