جستجوی مقالات مرتبط با کلیدواژه "محلول غذایی" در نشریات گروه "زراعت"

Most growers do not pay attention to the issue of proper nutrition, including the proper ratio of elements in the nutrient solution and changing the concentration of each element and their ratio at different stages of growth. Lack of available information in this regard, in the present study, it has been decided to evaluate the effect of different ratios of nitrogen and potassium on the quantitative and qualitative characteristics of tomato fruit under hydroponic conditions. The balance of nutrients in the culture medium is one of the factors affecting the yield and quality of crops and horticulture. The present study was conducted to investigate the effects of different ratios of nitrogen and potassium on the quantitative and qualitative characteristics of Hirad tomato fruit in hydroponic conditions. Treatments include concentrations of nitrogen and potassium in the vegetative and reproductive period including 1) nitrogen and potassium at concentrations of 130 and 250 ppm in the vegetative stage and 160 and 350 ppm in the reproductive stage; 2) nitrogen and potassium at concentrations of 140 and 260 ppm in the vegetative stage and 170 and 360 ppm in the reproductive stage, respectively; 3) nitrogen and potassium at concentrations of 150 and 270 ppm in the vegetative stage and 180 and 370 ppm in the reproductive stage, respectively; and 4) nitrogen and potassium were at concentrations of 160 and 280 ppm in the vegetative stage and 190 and 380 ppm in the reproductive stage, respectively. The results showed that the nutrition of tomato plant with different ratios of nitrogen and potassium affects different characteristics of the plant such as quantitative and qualitative indicators. The highest stem diameter value was obtained in the vegetative and reproductive stages in treatment 3. Treatment 2 showed the highest yield of single plant, total acid and fruit lycopene, and in treatment 4, the highest amount of fruit chlorophyll and soluble solids was observed. Also, the highest ascorbic acid content was obtained in treatment 1. In general, in order to achieve maximum yield and improve the quality of tomato fruit, it is recommended to use more potassium and less nitrogen.

Green house studying especially for salinity stress needs suitable medium. It is necessary to determine suitable medium in greenhouse studies for screening germplasm, which is easily available, stable in terms of electrical conductivity and cost-effective. Soil, and Perlite are common mediums which are used in green house researches generally, but there weren’t enough reports for study hydroponic system for screening sugar beet germplasm. Drought and salinity stress happens at the same time in most regions of Iran and because of similar tolerance mechanisms for these stresses, drought tolerant germplasm could be used in screening for salinity.so the goal of this project was to evaluate different medium especially hydroponic to screening sugar beet drought tolerance genotype in salinity stress.

The project was conducted in two experiments: (a) A factorial experiment based on completely randomized design with four replications was conducted in SBSI research greenhouse. The first factor was three planting media in combination with nutrition solution as follows: 1) loamy soil with about 5% organic matter, 2) perlite with Hoagland solution, 3) hydroponic environment with Hoagland solution. The second factor consisted of two levels of salinity including normal and salinity (16 dS m-1) treatments and the third factor consisted of two sensitive and tolerant genotypes. (b) 17 selected genotypes were investigated in greenhouse with perlite medium under control and salinity 16 dS m-1 in factorial experiment based on completely randomized design with four replications. Different quantitative and qualitative traits such as root. Shoot and total dry weights, K/Na, Soluble carbohydrates, glycine betaine were measured in both experiments and statistical analysis were done by MSTATC and SPSS and mean were compared in Duncan multiple range test at (α=0.05).

Cross effects of medium and salinity were significant on total and shoot dry weights, P, K/Na. Cross effects of medium, salinity and genotypes were significant on most of the traits. Crop yields under salinity stress were less in soil in comparison to other mediums, also salinity had significant effect on soil EC and Na (P≤0.01), soil and perlite were salinized respectively 6 and 2 times in comparison to normal condition. Which shows that soil is not stable medium for salinity study in green house. The highest yield (3.31 g p-1) was obtained from hydroponic. Yields achieved from hydroponic and perlite mediums were similar under salinity, but water consumption was more in hydroponic than perlite. In establishment stage, the total dry weight, soluble carbohydrates, glycine betaine and K/Na ratio were suitable for selection of sugar beet genotypes under salinity stress. According to all measurements, the clustering in establishment stages and Stress Tolerance Index (STI), HSF-91018, HSF-91040, HSF-92870, HSF-92881, HSF-92884, genotypes were selected as tolerant genotypes as controls.

Sensitive and tolerant genotypes were not distinguished well in hydroponic medium, which related to its potential and was mentioned in other reports. Hydroponic and perlite were in the same group for different traits especially they became less salty than soil but hydroponic system is not useful for root beet but it would be suitable for forage beet because biomass production is more in this condition. Also, soil is not suitable medium for study salinity researches because it became seven times more salty than normal condition. As a result perlite is the best medium for salinity studies in sugar beet because it becomes less salty, it has low weight and cost and has less side effects on environment. According to all measurements, the clustering in germination and establishment stages and Stress Tolerance Index (STI), HSF-91018, HSF-91040, HSF-92870, HSF-92881, HSF-92884, genotypes were selected as tolerant genotypes as controls.

Licorice (Glycyrrhiza glabra L.) is a perennial medicinal plant which its root and rhizome extract broadly use for food and pharmaceutical industries. Considering the necessity of its domestication as an alternative approach for its wild collection, this experiment was counducted to investigate the effect of electrical conductivity (EC) of nutrient solution on growth and yield of three licorice ecotypes under hydroponic culture.

the experiment was conducted as factorial based on randomized complete block design with three replications in Research Greenhouse of Department of Horticultural Science and Landscape Engineering, University of Tehran in 2018. Treatments were included four levels of electrical conductivity (EC) of nutrient solution (1.5, 2, 2.5 and 3 dS.m-1) and three licorice ecotypes (Baft and Lalehzar from Kerman province and Eqlid from Fars province). In this study, some morphophysiological traits such as plant height and diameter, main stem diameter, number of lateral branches per plant, internode length, leaf area, root length and diameter, root and shoot fresh and dry weight and some biochemical traits such as Chlorophyll index, total phenol content and total antioxidant activity were measured.

the results showed that there was a significant difference between ecotypes on all studied traits except total phenol and total antioxidant activity. Also, different levels of electrical conductivity significantly affected the studied traits, except for root dry weight and total phenol. The interaction effect of both treatments was significant in terms of the morphophysiological and biochemical traits. In each of the three ecotypes studied, with increasing the electrical conductivity of the nutrient solution, plant height and diameter, internode length, leaf area and root diameter showed a decreasing trend. The highest dry weight of shoots was observed in Baft ecotype from Kerman with electrical conductivity levels of 1.5 and 2 dS.m-1 (4.51 and 4.91 g.plant-1, respectively) and Eghlid ecotype from Fars with electrical conductivity of 2.5 dS.m-1 (4.91 g.plant-1). Also, Baft ecotype from Kerman showed the highest dry weight of root (16.02 g.plant-1) in electrical conductivity of 3 dS.m-1. In terms of biochemical traits, the highest amount of chlorophyll index was observed in Lalehzar ecotype from Kerman and electrical conductivity level of 2.5 dS.m-1. The highest amount of total phenol and percentage of antioxidant activity was related to Lalehzar ecotype at the electrical conductivity level of 3 dS.m-1.

according to the results, Baft ecotype from Kerman province and then Eqlid from Fars province in range of electrical conductivity level of 1.5-2 dS.m-1 performed better while in terms of quality criteria, Lalehzar ecotype from Kerman showed the highest amount in electrical conductivity of 3 dS.m-1 compared to other treatments.

Elements such as nitrogen (N), molybdenum (Mo), and cobalt (Co) are needed to improve the quantity and quality of beans. In order to study the effects of these elements on pod yield and concentration of nutrients in bean, a factorial pot experiment was conducted in 2016 in greenhouse conditions at University of Zanjan, using a CRD with three replications. The experimental factors consisted of four levels of N (50, 100, 150, and 200 mg/l), three levels of Mo (0.067, 0.2, and 0.6 mg/l), and Co (0.006, 0.06, and 0.3 mg/l). The results showed that the highest dry weight of pods was obtained from treatment of N100Mo0.2Co0.06 which was 34.05 g/pot and had no significant difference with N150Mo0.6Co0.06 treatment. The application of different levels of factors increased the concentrations of N, P, and Mg in bean leaves in treatments of N200Mo0.6Co0.3, N200Mo0.6Co0.006, and N150Mo0.6Co0.3 and the highest increase in concentrations of mentioned elements were 6.94, 0.91, and 0.41% respectively. However, the concentrations of K and Ca decreased as a result of the application of the factors. The highest concentrations of Fe, Mn, Cu, Mo, and Co bean were measured in treatments of N200Mo0.6Co0.006, N150Mo0.2Co0.006, N200Mo0.6Co0.3, N150Mo0.6Co0.3, and N150Mo0.067Co0.006 which were 490, 185.4, 8.26, 284.5, and 54.9 mg/kg, respectively. Overall, according to the results, N100Mo0.2Co0.06 is recommended for bean.

In soilless culture, lack of correct management in fertigation causes stress in plants due to restricted root volume and low water holding capacity of substrate. The present study aimed to assess managing the fertigation practice and foliar application of potassium sulfate in soilless culture of strawberry cv. paros. A factorial experiment was conducted with two factors including fertigation frequency at three levels (1, 4 and 10 times per day) and foliar application with potassium sulfate at three levels of concentration (0 as control, 1 and 2 g/L). The experiment was carried out based on a complete randomized design with three replications in Vali-e-Asr University of Rafsanjan. Results indicated that increasing the fertigation frequency up to four times a day led to a significant increase in dry weight of shoot and root, number of fruits, concentration of chlorophyll a and b, leaf relative water content and leaf Ca and Mg content. The highest values of leaf area, fruit weight, number of inflorescence as well as potassium and iron content of leaf and root were obtained by 10 times of fertigation per day. Potassium sulfate foliar application with concentration of 1 g/L had the most effect on leaf area as well as shoot, root and fruit dry weight, vegetation index increased in plants treated with 2 g/L potassium sulfate compared with those without any foliar application treatment. The highest content of leaf soluble carbohydrates belonged to the plants treated with once-a-day fertigation and foliar application of 2 g/L potassium sulfate.

This experiment was conducted in order to investigate morphological and physiological responses of Kentucky bluegrass (Poa pratensis L.) to salinity and silicon application in horticultural science department at the University of Zanjan in 2015. The salinity levels (0, 40 and 80 mM NaCl) and sodium silicate (0, 0.75 and 1.5 mM) were applied in complete nutrient solutions. Salinity reduced root and shoot growth, visual turf quality, leaves chlorophyll and potassium content, whereas electrolyte leakage, proline and sodium content increased with increasing salt concentration in nutrient solution. Silicon application ameliorate adverse effects of salinity in all factors except in potassium content and this effect was more pronounced in 80 mM NaCl. Although there was no significant difference between 0.75 and 1.5 mM sodium silicate in visual turf quality, root growth and chlorophyll content, altogether, application of 1.5 mM silicon had better results to increase salinity tolerance in Kentucky bluegrass, suggesting that higher concentrations of silicon must be evaluated.

Calcium is one the most important essential elements in plant growth and development. This element influences many physiological aspects of plant tissues even after harvesting. Calcium has also an important role in integrity and hardness of plant cells. In addition، calcium content of many horticultural crops is seen as a quality factor. Therefore، in this research effect of different calcium concentrations of nutrient solution on growth and development of two cut rose cultivars (Utopia and Dolce Vita) were investigated. This experiment was conducted as factorial based on completely randomized design during 2011. The factors were cultivar with two levels and calcium in four concentrations of 150، 220، 300 and 400 mg/l. The total number of treatments was 8 with 5 replications. The results showed that the effects of cultivar and calcium levels were significant on measured parameters. The analysis of variance of data showed that there were significant differences (p < 0. 05) for some parameters including: length and diameter of flower stem and vase life of cut flower between two cultivars. Results also showed that with increasing calcium concentrations in nutrient solution the overall trend was to increase flowering parameters (p < 0. 05). Therefore، increasing calcium levels up to 400 mg/l resulted in improvement of flowering parameters in both cultivars.

In order to investigate the effect of different levels of nutrient solution concentration and times and frequencies of foliar applications on dry weight, nitrogen, phosphorus and potassium concentrations of leaf and corm of saffron, a pot experiment was conducted as a completely randomized design with factorial arrangement and three replications under open door conditions in research garden of ferdowsi university, faculty of agriculture. The experimental treatments were included 4 levels of solution concentration (0, 4, 8 and 12 per 1000) and 7 levels of time and frequency of foliar applications (F1: foliar application on th February, F2: foliar application on 18th February, F3: foliar application on 5th March, F4: foliar applications on 3th and 18th February, F5: foliar applications on 3th February and 5th March, F6: foliar applications on 18th February and 5th March, F7: foliar applications on 3th and 18th February and 5th March). Results of variance analysis showed that fresh and dry weight of corm and leaf were not influenced by concentration, time and frequency of foliar applications. Also, comparison of nitrogen, phosphorus and potassium concentrations of leaf and corm showed that there was no significant difference between levels of foliar treatments and control. Therefore, it seems that due attention to pattern of leaf and low nutrient demand of saffron, foliar applications in different levels of nutrient solution concentrations and times and frequencies of foliar applications could not increase vegetative growth and consequently, could not improve the growth and nutritional properties of saffron corms.

This study was conducted to evaluate different nutrient solutions effects on Agria potato mini-tubers production under aeroponic system. The experiment was conducted in the laboratory and greenhouse of Ardabil Sabalan Behparvar Company in 2013. Four recommended nutrient solutions including: Lommen and Struik (1992), Kang and Han (2005), Otazu (2010) and Hoagland and Arnon (1950) were used in a Randomized Complete Block Design with three replications. Some important traits such as: plant height, no. of main stem per plant, no. of mini-tubers and mini-tubers weight per m2, mini-tubers weight mean and mini-tubers storage conditions were measured and recorded during the growth period and after harvesting time. Results of ANOVA showed that nutrient solutions were significant on mini- tubers numbers and mini-tubers weight per m2, and plant height. Maximum mini-tubers weight per m2 (11074 g), mini-tuber weight mean (8.64 g) and plant height (87 cm) were observed in Lommen and Struik nutrient solution respectively. The highest number of mini-tubers (1600 per m2) was achieved from 20 plantlets per m2 (80 mini-tubers per plant), It was more than the conventional system, with peat moss bed and 100 plantlets per m2,that produce about 200 mini-tubers per m2 (2 mini-tubers per plant).

To evaluate the effect of limited application of nitrogen (N) on the height control of geranium (Pelargonium hortorum) and improving its quality performance، an experiment was conducted based on a complete randomized block design with three replications in the greenhouse environment through the years 2011-2012. Geranium seedlings were cultivated in the pots filled with peat-based substrate (peat، 80 vol. percent + sandy loam field soil 20 vol. percent). For the limited application of N، four different nutrient solutions with the same macro and micro elements، except N levels of 2. 5، two، 1. 5 and one mM were applied. The rate of ammonium to nitrate nitrogen for all treatments was kept as 2 to 80 percent. The traits such as plant height، number and length of shoots، number of florescence and number of flowers in the florescence، pedicle length and leaf number، leaf area، chlorophyll، antocianins، fresh and dry weight of shoot and root were measured at the end of the experiment. Limitation of N application from 2. 5 mM to 1. 5 mM in the nutrient solution، although reduced the length of shoot، but did not affect negatively the quality of plants. Farther decreasing of N level to 1 mM، negatively influenced the all quality and quantity parameters of the plant and may not be introduced for production of geranium.

Potassium (K) has a special place in improving the quality of agricultural products. To evaluate the effect of K concentration in nutrient solution on lycopene content, vitamin C and qualitative characteristics of cherry tomato in NaCl salinity conditions, an experiment was carried out as a completely randomized design with five treatments and three replications at university of Tabriz, Tabriz, Iran, in 2010. Treatments consisted of four concentrations of K (0.2, 2, 7 and 14 mM) in nutrient solution with 60 mM NaCl concentration. A nutrient solution treatment without salinity was considered as control. The experiment was conducted in greenhouse, in a hydroponic system. The results indicated that increasing of K concentration increased lycopene content in fruit. Lycopene content in control treatment showed significant difference (P<0.01) in comparison with salinity treatments. With increasing the K concentration (except at 14 mM concentration), vitamin C content was increased, but indicated no statistically significant difference. Vitamin C content in saline conditions was more than control treatment, but showed no significant difference. Adding potassium concentration in nutrient solution improved yield and enhanced quality parameters such as percentage of dry matter, soluble solids and electrical conductivity of fruit extract. Since in saline conditions, the qualitative characteristics of tomato at 7 mM concentration were in the best situation, therefore using this concentration is recommended.