Pomology
M. Safari Motlagh; B. Kaviani; J. Ashegh
Abstract
Introduction: In recent years, applying humic acid has been common in enhancing the quantitative and qualitative characteristics of crops. The use of biofertilizers instead of chemical fertilizers has an effective role in increasing the health of plants, animals, and humans, and reducing environmental ...
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Introduction: In recent years, applying humic acid has been common in enhancing the quantitative and qualitative characteristics of crops. The use of biofertilizers instead of chemical fertilizers has an effective role in increasing the health of plants, animals, and humans, and reducing environmental pollution. Chemical fertilizers are gradually being replaced by biofertilizers. Strawberry is a fruit with high nutritional value. Choosing the right nutritional conditions such as fertilizers and suitable cultivation beds to achieve high quantitative and qualitative yield in this plant is inevitable. In recent years, the use of humic acid has been common in enhancing the vegetative and generative characteristics of crops. Humic acid is a rich source of potassium, phosphorus and nitrogen. The method of application of humic acid has an effective role in improving the quantitative and qualitative characteristics of plants. Combining some cultivation beds such as perlite, composts, and fertilizers including agricultural waste (such as rice bran and tea wastes) into soil cultivation beds have had an effective role for improving the quantity and quality of plants. Materials and Methods: A pot experiment was conducted to evaluate the effects of foliar application of humic acid and different cultivation beds on morphology, flowering and fruiting of two strawberry (Fragaria × ananassa) cultivars ‘Local’ and ‘Selva’ in Islamic Azad University, Rasht Unit, on 2016. Different concentrations of humic acid (0, 300, 600, and 1000 mg l−1) were applied as foliar application in two steps (late March containing three leaves and late April containing five leaves) on strawberries cultivated in different beds (usual soil and usual soil with rice bran, or perlite, or tea wastes). The experiment was carried out as factorial based on a randomized complete block design (RCBD) with four replications. Some traits including plant height, root number, root length, leaf length, shoot number, shoot length, shoot diameter, leaf number, node number, flowering time, flower diameter, flower number, fruit number and fruit weight were measured. Results and Discussion: Analysis of variance showed that the interaction effect of humic acid × cultivation bed ×cultivar on plant height, shoot length, shoot number, leaf number, root length, root number, flower diameter (p≤0.01), fruit weight, and fruit number (p≤0.05) was significant. The interaction effect of these three factors on shoot or stolon diameter, leaf length, flowering time and flower number was not significant. Results of mean comparison showed that the highest shoot or stolon number (14.82) were obtained in ‘Selva’ cultivar treated with 1000 mg l−1 humic acidcultivatedin usual soil with tea wastes. The highest fruit weight (35.45 g) and fruit number (15.41 per plant) were obtained in ‘Selva’ cultivar treated with 1000 mg l−1 humic acidcultivatedin usual soil with perlite. The maximum leaf number (16.03 per plant) was obtained in the treatment of 300 mg l−1 humic acid and the cultivation bed of usual soil and rice bran in ‘Local’ cultivar. Minimum fruit number (3.58) and fruit weight (8.23 g) were obtained in ‘Local’ cultivar cultivated in usual soil bed without humic acid. The highest number of root (19.56) was obtained in the treatment of 600 mg l−1 humic acid and the cultivation bed of usual soil with perlite in ‘Local’ cultivar. The highest amount of flower diameter (7.85 mm) was calculated in the treatment of 1000 mg l−1 humic acid and the cultivation bed of usual soil with tea wastes on ‘Selva’ cultivar. These results suggest that humic acid foliar application might be benefit to enhance fruit characteristics of strawberry. Totally, humic acid application increased growth and yield of strawberry. Since the most important parameters for increasing the quality of strawberry fruit is fruit characteristics, it is recommended to use 1000 mg l−1 of humic acid cultivated in the usual soil mixture with tea wastes. Strawberries are widely cultivated worldwide due to their high nutritional value. Chemical fertilizers have been used as a way to increase crop yields, but have led to problems such as nitrate accumulation, pot life, and poor quality and environmental pollution. Therefore, organic fertilizers have been used. Humic acid can improve quantitative and qualitative production by having properties such as providing more available essential elements and increasing plant resistance to various biological and non-biological stresses. A positive association has been reported between the use of humic acid and the increases in growth, yield and product quality in strawberries and other plants. Proper cultivation bed plays an important role in the optimal growth and development of plants. Salinity increases osmotic stress, ion toxicity, oxidative stress and food imbalance. The use of compost fertilizer and foliar application of humic acid increased the growth, yield and quality of strawberry fruit.
rasoul abaszadeh faruji; mahmood shoor; ali tehrani far; bahram abedy; nasim safari
Abstract
Introduction: Ornamental plants play a vital role in meeting the mental and spiritual needs of peoplethat considered significance from commercial point of view as well. Optimal production of agricultural products requires suitable soil and adequate and absorbable nutrients for plant. Organic materials ...
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Introduction: Ornamental plants play a vital role in meeting the mental and spiritual needs of peoplethat considered significance from commercial point of view as well. Optimal production of agricultural products requires suitable soil and adequate and absorbable nutrients for plant. Organic materials are important because ofimproving soil physical properties and soil fertility. Soil fertility depends on the content oforganic matter as well as the quality, quantity and dynamics of these materials insoil. Organic acids are an important source of organic matter. One of the most abundant forms of organic matter in nature is humic compounds which can be found in all soil and water environment. They play an important role in cation exchange, nutrients release, phosphorus buffering capacity and metal and toxic organic molecules maintenance.
Materials and Methods: In order to evaluate the effect of humic substances on morphological characteristics of geranium, thisexperiment was conducted in research greenhouse of Ferdowsi University of Mashhad during the years 2014 and 2015. The experiment was carried out as factorial based on completely randomized design with two factors and three replications. The first factor hadfour levels of humic acid (0, 0.2, 0.5 and 1 g/l), and the second hadfour levels of fulvic acid (0, 0.2, 0.5 and 1 g/ml). Treatment was usedalong with irrigation. Morphological characteristics included the number of leaves, number of nodes, number of branches, plant height, root length, leaf area, fresh weight of shoot, fresh weight of leaf, fresh weight of root, dry weight of shoot, dry weight of leaf, dry weight of root, volume of shoots, volume of root, fresh weight of shoot were measured at the end of the experiment. Statistical analysis of the results was performed by using Jmp-8 software. Charts were drawn using Excel 2010 and difference among treatments means were compared with LSD test.
Results and Discussion: The results of means comparison showed that combined use of humic acid and fulvic acid hadpositive effects on growth traits such as height, internode length, root length, fresh weight of shoot, fresh weight of root, fresh weight of leaf, dry weight of shoot, dry weight of leaf, volume of shoot, volume of root and leaf area. Research had shown that the application of humic fertilizers increased nitrogen content in shoots of the plant. It wasreported that nitrogen compounds existed in humic acid are important factors affecting the growth of plants. Humic acid also increasedshoot growth by increasing the uptake of nitrogen, calcium, phosphorus, potassium, manganese, zinc, iron and copper as well as hormone-like properties. It wasalso found that humic acid enhancedplant growth by increasing the activity of the RuBisCO enzyme and the subsequent increase in photosynthetic activity. Furthermore, humic acid reduced the pH of alkaline soils and causedthe nitrogen to be absorbed to a greater extent. The use of humic substances increased the leaf area and thus photosynthesis, therefore leading to the production of more dry matter in plants. Humic fertilizers also had a significant effect on root growth. Researchers had suggested that the presence of oxygen groups in humic acid increased lateral root growth. Although humic acid increased the growth of both root and shoot, its effectiveness on the root system wasmore evident.
Conclusions: This experiment was conducted with the aims of evaluating the effect of humic organic fertilizers, reducing the harmful effects of chemical fertilizers and improving the quality of plant growth in geranium. According to the results obtained from the present research, it can be concluded that combined application of humic acid and fulvic acid had greater effects on the majority of traits compared to the sole application of aforementioned compounds.
M.B. Amiri; Parviz Rezvani Moghaddam; Mohsen Jahan
Abstract
Introduction: In recent years, the effect of ecological inputs on soil properties and plant growth characteristics has received renewed attention. Although the utilization of mineral fertilizers could be viewed as the best solution in plant productivity, this approach is often inefficient in the long-term ...
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Introduction: In recent years, the effect of ecological inputs on soil properties and plant growth characteristics has received renewed attention. Although the utilization of mineral fertilizers could be viewed as the best solution in plant productivity, this approach is often inefficient in the long-term in many ecosystems due to the limited ability of low-activity clay soils to retain nutrients. Intensive use of chemical fertilizers and pesticides in agricultural systems is also known to have irreversible effects on soil and water resources. Maintenance of soil fertility as a permanent bed for continuous production of agricultural products is one of the most important issues affecting the sustainability of food production. In order to achieve healthy food production, application of ecological inputs such as soil amendments and bio-fertilizers is inevitable. Humic substances are a group of heterogeneous molecules that are bonded together by weak forces; therefore, they have a high chemical stability. This material included 65 to 80 percent of total soil organic matter. Application of bio-fertilizers is an appropriate alternative of chemical fertilizers to enhance soil fertility. In fact, bio-fertilizers include different types of free living organisms that convert unavailable nutrients to available forms and enhance root development and better seed germination. Mycorrhiza arbuscular fungi are coexist microorganisms that improve soil fertility, nutrients cycling and agroecosystem health. Mycorrhizal fungi are the most abundant organisms in agricultural soils. Many researchers have pointed to the positive roles of mycorrhizal fungi on plants growth characteristics. Echium amoenum is a perennial plant belongs to Boraginaceae family. This plant is native of North of Iran. Petal extract of E. amoenum have sedative, diaphoretic, anti-inflammatory and anti-depressant effects. These plants are wild perennial herbs and known in Iran as oxtongue. It is one of the most important medicinal plants in Iranian traditional medicine. Petals of Iranian oxtongue have been advocated for a variety of effects such as demulcent, anti-inflammatory and analgesic, especially for common cold, anxiolytic, sedative and other psychiatric symptoms including obsession in folk medicine of Iran. Despite many research on the effects of organic acids and bio-fertilizers on different crops, there is scarce information on the effects of these factors for many medicinal plants. Therefore, in this study effect of organic acids and bio-fertilizers on morphological characteristics and yield of Echium amoenum in a low input cropping system was studied.
Materials and methods: In order to evaluate the effects of soil amendments and different bio-fertilizers on morphological characteristics and seed yield of Echium amoenum, an experiment was conducted based on randomized complete block design with three replications during 2011-2013 growing seasons, at the Research Farm of Ferdowsi University of Mashhad, Iran. Treatments were eight different types of soil amendments and bio-fertilizers concluding: 1) Humic acid, 2) Fulvic acid, 3) Nitroxin® (Azotobacter spp. and Azospirillum spp.), 4) Biophosphorous® (Bacillus sp. and Pseudomonas sp.), 5) Biosulfur® (Thiobacillus spp.), 6) Mycorrhiza (Glomus mosseae), 7) Mycorrhiza (Glomus intraradices), and 8) no fertilizer as control.
Result and Discussion: The results showed that mycorrhiza species increased flower yield compared with control, as the flower yield in treatments of G. mosseae and G. intraradices were 24 and 11 percent more than control, respectively. Soil amendments and different bio-fertilizers increased the number of flower cycle per plant compared with control. Although the effect of biophosphorous® was more pronounced, as the number of flower cycle per plant increased from 342 to 1322 cycles in control and biophosphorous® , respectively. Humic acid treatment increased seed yield, biological yield, seed weight and seed number per plant by 82, 66, 63 and 66 percent compared with control, respectively. It seems that different species of mycorrhiza improved morphological characteristics and yield of Echium amoenum, because of better conditions to absorption and transportation of nutrient to the plant. It has been reported that organic acids provide favorable conditions for plant growth and development through improvement of physical, chemical and biological properties of the soil. Therefore, it could be concluded that improvement of most studied traits in the present study was as a result of use of organic acids.
Conclusions: Generally, our results showed that organic acids and biological fertilizers had positive effects on most of studied criteria. The highest flower and seed yields were obtained from G. mosseae and Humic acid treatments, respectively.
rahman Ebrahimzadeh abdashti; Mohammad Galavi; Mahmoud Ramroudi
Abstract
Introduction: Roselle (Hibiscus sabdariffa L.) belongs to the Malvaceae family, and is an annual or biennial plant that cultivated in tropical and subtropical regions for its stem fibers, eatable calyces, leaves and grains. Roselle is resistant to relatively high temperatures throughout the growing and ...
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Introduction: Roselle (Hibiscus sabdariffa L.) belongs to the Malvaceae family, and is an annual or biennial plant that cultivated in tropical and subtropical regions for its stem fibers, eatable calyces, leaves and grains. Roselle is resistant to relatively high temperatures throughout the growing and fruiting times. Continuous use of chemical fertilizers destroys the soil ecological balance, reduces soil fertility and groundwater pollution is caused. In contrast, organic fertilizers are very safe for human health and the environment. It is made by recycling organic material as plant and animals waste, and food scraps in a controlled process. Of the organic fertilizers can be noted to compost, vermicompost, cattle manure andhumic acid. The study was carried out in order to sustainable agriculture. The aim of this study was to investigate the effects of organic and chemical fertilizers on some quantitative traits and anthocyanin of roselle.
Materials and Methods: The experiment was performed in complete randomized block design with ten treatments and four replications in research field of agricultural faculty, university of zabol. The treatments included T1: control, T2: NPK in a ratio of 2:1:1 (300 kg ha-1), T3: cattle manure (20 t ha-1), T4: compost (10 t ha-1), T5: vermicompost (5 t ha-1), T6: humic acid foliar in a ratio of 1.5 per thousands, T7: 50% of T2 and T6 , T8: 50% of T3 and T6, T9: 50% of T4 and T6 and T10: 50% of the T5 and T6.
Five plants were chosen and an average of five plants was calculated as the single plant for measuring of variables that included the height, number of branches, stem diameter, shoot fresh weight, number of fruits per plant, fruit weight, number of seeds per plant, fresh and dry weights of sepals, inflorescence length, length and diameter of fruit. Method of Wagner has been used for the anthocyanin measurement.
Results and Discussion: Results of this research showed that the application of different fertilizers increased the height, number of branches and stem diameter per plant in different stages of growth. Mean comparison showed that there were significant differences between the treatments and control in most traits, so that the maximum height, number of branches and stem diameter belonged to the treatment of organic and chemical fertilizer with humic acid (T8, T9 and T10). The highest number of fruits and seed yield per plant (41/98%) was obtained from the T9 treatment compared to the control. This result was corresponded with the results of other researchers in the roselle.
The result showed that inflorescence length, length and diameter of fruit had the highest values by using the cattle manure + humic acid (T8); and so measured characters had the lowest values in control treatment. Effect of different fertilizer treatments on fruit fresh weight, fresh and dry weights of sepals had statistically significant differences. The highest and the lowest values of fruit fresh weight, fresh and dry weights of sepals were obtained from T9 treatment (compost + humic acid) and control treatment, respectively.
Compost improves conditions for the plant growth. Humic acid stimulates the growth hormone and increases the absorption of nutrients by plant. So, with these reasons it seems that higher growth features and further calyx yield were achieved by applying compost + humic acid than other treatments.
The effect of treatments organic and chemical fertilizers with humic acid on the amount of anthocyanin was higher compared with using them separately. Compost, vermicompost and cattle manure fertilizers are containing humic acid substances and humic acid (phenolic compound derivatives) is a precursor for the synthesis of anthocyanidin (flavonoid structure), therefore they correlated with the increasing anthocyanin in treatments organic fertilizers and chemical with humic acid.
Conclusions: The results showed that all applied fertilizers treatments improved growth features, further calyx yield and anthocyanin amount, than the situation of non-use of fertilizer. Nevertheless, the effect of the treatments organic fertilizers with humic acid on vegetative growth, fruit and sepals yield and anthocyanin content per sepals was higher compared with using them separately and using chemical fertilizers.
Therefore, to achieve maximum vegetative growth, fruit and sepals yield and anthocyanin content per sepals using treatments of organic fertilizers with humic acid were better than other fertilizer treatments in this research. Therefore, it seems that, in terms of sustainable production and the environmental protection of roselle, applications of organic fertilizers may be viable alternatives to chemical fertilizers.
R. Naghibi; P. Rezvani Moghaddam; A. Balandari; Reza Ghorbani
Abstract
Introduction: In recent years many farmers in Iran interested in to cultivate and produce different medicinal plants which are so important in traditional agriculture in Iran. In order to reduce the environmental impacts of using chemical inputs and also to increase the quality of plant secondary metabolite ...
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Introduction: In recent years many farmers in Iran interested in to cultivate and produce different medicinal plants which are so important in traditional agriculture in Iran. In order to reduce the environmental impacts of using chemical inputs and also to increase the quality of plant secondary metabolite components, the emphasis is on sustainable agriculture base on using of organic and biological fertilizer. Dwarf chicory (Cichorium pumilum Jacq.) is an annual plant from Asteraceae family. Dwarf chicory is classified by jacq as subspecies of the cultivated species Cichorium endeva which consumed for healing a variety of diseases such as bacterial infection, poisoning and rheumatism. The use of organic fertilizer in the form of humic acid and fulvic acid play an important role in sustainable agriculture. Humic substances can be added to the soil for improvement the crop yield. A benefit of humic acid due to its ability to complex metal ions and form aqueous complexes with micronutrients and also may form an enzymatically active complex, which can be carry on reactions that are usually assigned to the metabolic activity of living microorganisms. In additional of using organic fertilizers, the biological fertilizer like mycorrhiza fungi is a good approach in agriculture. Mycorrhizal fungi have been used to enhance the plant growth and yield of medicinal crops and to help maintain good soil health and fertility that contributes to a greater extent to a sustainable yield and good quality of the products. The present study was conducted to evaluate the effects of organic fertilizers and mycorrhizae inoculation on quantitative and qualitative characteristics of dwarf chicory (Cichorium pumilum Jacq.) in different cuttings.
Materials and Methods: The experiment was carried out in a factorial layout based on randomized complete block design with three replications at Research Station, Faculty of Agriculture, Ferdowsi University of Mashhad (59°28 E and 36°15 N ) in 2012-2013 growing season. The experimental treatments were all combination of organic fertilizers in four levels (cow manure, humic acid, fulvic acid and control) and three levels of Mycorrhiza inoculation (Glomus mosseae, Glomus intraradices and no inoculation) and The collected data were analyzed as split- plot in time based on randomized complete block design (due to having two cuttings during growing season) compared. The 12 fertilizer treatments and two cuts were considered as main and sub plots, respectively. The plots were 2.5*5 m (12.5 m2). The soil of the experimental field was silty loam with pH 8.09, contains total N (0.08 %), available P (10.25 ppm), and available K (286 ppm) with an EC of 1.26 dsm−1. The parameters measured were such as: leaf weight per plant, stem weight per plant, leaf/stem ratio, the leaf area index, fresh yield, dry matter yield and the poly phenol content. The poly phenol content was determined based on Wojdylo et al. (2007) method. The results were analyzed using SAS statistical program and MSTAT-C. The mean comparisons were performed using least significant difference (LSD) test.
Results and Discussion: The results showed that the highest (4544 kg.ha-1) and the lowest dry matter (1739 kg.ha-1) yield were obtained in second and first cut, respectively. The results indicated that inoculation with mycorrhizal species increased the leaf area index, dry matter yield and leaf weight per plant compared with control treatment. However, there was no significant difference between G. mosseae and G. intraradices in terms of former mentioned criteria. The results showed that using organic fertilizers improved leaf area index, dry matter yield and leaf weight per plant. The highest dry matter yield (3470 kg/ha), leaf area index (1.01), stem weight per plant (11.50 g) and leaf weight per plant (0.72 g) were obtained in humic acid treatment. Studied treatments and also different cutting had no significant effect on poly phenols contents of leaves. In generally, our results showed that application of biological and organic fertilizers improved the most of studied traits of dwarf chicory and G.mosseae + humic acid treatment was the best.
Conclusion: In this paper we have shown that yield contributing characters were significantly influenced by different treatment combinations of humic acid and mycorrhizal fungi and became maximum when humic acid and Glomus mossae were applied. In order to minimize contamination of the environment and sustainable agriculture, using biological and organic fertilizers can lead to reduction of chemical fertilizers application in agro ecosystems.
M. Amani Beni; A. Hatamzadeh; A. Nikbakht; M GH; S. Nikkhah Bahrami; S. Davarpanah
Abstract
Tuberose flower (Polianthes tuberosa L.) is an important commercial cut flower in the world, however the short vase life is one of its major problems. So, an experiment was carried out by using five different levels of humic acid (HA) mixed with sucrose and seven different levels of silver nanoparticles ...
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Tuberose flower (Polianthes tuberosa L.) is an important commercial cut flower in the world, however the short vase life is one of its major problems. So, an experiment was carried out by using five different levels of humic acid (HA) mixed with sucrose and seven different levels of silver nanoparticles (SNP) mixed with sucrose in vase solution on tuberose cut flowers cv." Single". The results indicated that there were significant differences between treatments. The decline of fresh weight in flowers treated with 25, 50 and 75 mg L-1 HA was fewer compared to other levels. Also, the effect of HA on vase life and water uptake index was significantly higher in 25 mg L-1 HA (2.25 days more than control). SNP treatments increased the water uptake, fresh weight, total protein and declined lipid peroxidation amount compared to the control flowers. The results also showed that flowers which were treated with 1 mg L-1 SNP had 2.87 days vase life more than the control flowers. To sum up it can be demonstrated that suitable levels of HA and SNP improved better morphological and physiological properties and eventually increases the vase life of cut tuberose flowers.
Mohammad javad Nazari deljou; Neda Allahverdizadeh
Abstract
To study the effect of foliar application of humic acid on morpho-physiological traits, nutrients uptake and postharvest vase life of cut marigold, an experiment was conducted with five levels of humic acid (0, 250, 500, 750 and 1000 ppm) based on completely randomized design with three replications. ...
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To study the effect of foliar application of humic acid on morpho-physiological traits, nutrients uptake and postharvest vase life of cut marigold, an experiment was conducted with five levels of humic acid (0, 250, 500, 750 and 1000 ppm) based on completely randomized design with three replications. Based on the results, in compared with control, leaf number and leaf area, total phenol and aerial and root dry weight significantly influenced by humic acid. Accordingly, the highest flower number in compare with control plants was observed in 250 and 500 ppm concentrations. Also, foliar application of humic acid showed a significant effect on phosphorous and calcium uptake (P
soheila kamari; Gh. Peyvast; M GH
Abstract
Humic acid, which has hormone- like activity , not only enhances plant growth and nutrients uptake but also improve stress tolerance. To determine the effect of humic acid on the yield and vegetative characteristics of tomato an experiment was conducted with tomato cv. `Isabela` in 2008 in a plastic ...
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Humic acid, which has hormone- like activity , not only enhances plant growth and nutrients uptake but also improve stress tolerance. To determine the effect of humic acid on the yield and vegetative characteristics of tomato an experiment was conducted with tomato cv. `Isabela` in 2008 in a plastic tunnel at the Agriculture Faculty, Guilan University using randomized completely design with four treatments (0, 1, 2, 3 mg l-1 humic acid) and three replications. Humic acid was sprayed four times during the vegetation period with 10- day intervals after three weeks of planting. Results showed that humic acid could affect significantly (P
E. Chamani; B. Esmaeilpour; Y. Pourbeyrami Hir; H. Maleki Lajayer; A. Saadati
Abstract
Two separated experiments were conducted to evaluate the effects of different concentrations of thidiazouron (10, 20, 30, 40 and 50 µM) and humic acid (1, 10, 100, 1000 and 10000 ppm) on vase life of cut Alstroemria flowers. Experiments were carried out based on completely randomized design with 8 replications ...
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Two separated experiments were conducted to evaluate the effects of different concentrations of thidiazouron (10, 20, 30, 40 and 50 µM) and humic acid (1, 10, 100, 1000 and 10000 ppm) on vase life of cut Alstroemria flowers. Experiments were carried out based on completely randomized design with 8 replications in postharvest laboratory of Horticultural Department, Mohaghegh Ardabili University in 2009. The results showed that lower concentrations of humic acid had positive effects on flower vase life, water content of tissue and solution uptake, while didn’t affect relative fresh mass and leaf chlorophyll content. In both experiments results also indicated that humic acid in higher concentrations affected all traits, negatively. Howewer, this compound at 10000 ppm decreased flower vase life, water content, relative fresh mass, solution uptake and chlorophyll content. By increasing the humic acid concentration up to 100 ppm the vase life of cut flowers improved. Compared with control and other treatments, 1000 ppm of humic acid decreased flower vase life, considerably. The highest vase life of flowers devoted to 10 µm of TDZ, however higher concentrations of this compound reduced flowers vase life. Moreover, the highest solution uptake and leaf chlorophyll content obtained by 30 µm TDZ, while the highest relative fresh mass devoted to 40 µm of this compound.
