فهرست مطالب لادن آژدانیان

Trichoderma and vermicompost are important factors in improving and indirect growth stimulants in a variety of crops and orchards. This study is a factorial experiment based on a completely randomized design, under soilless cultivation conditions in the greenhouse, with 4 concentrations of Trichoderma harizianum isolate Bi: 0% (control), 10%, 20%, and 30% by volume of 60 liters of water and two levels of vermicompost: Control (no use of vermicompost) and 50% of pot volume (cocopeat and perlite (2:1)) with 6 replications were established by studying the effect on morphological properties of lettuce cultivar (Green Tower Mi). The highest weight of stem, leaf, and root based on the results of the 10% fungus concentration treatment was observed at the highest levels of 363.75 g, 325.08 g, and 26.35 g, respectively. Also, in the application of vermicompost, the heavier stem fresh weight (377.41 g), leaf fresh weight (348.87 g), and root fresh weight (24.11 g) had the highest weight compared to non-application. The highest number of leaves (36), stem diameter (20.64 mm), and leaf area (211.25 cm-2 g) were observed in fungal treatment with a concentration of 10%. The antioxidant activity of lettuce treated with vermicompost increased by 25.34% compared to the control. Therefore, with the positive effect of vermicompost and Trichoderma on the growth properties of lettuce, the use of these two treatments in planting this plant is recommended. Also, because there was no significant difference between the high levels of the fungus, it is possible to achieve the desired result with fewer savings and costs, even with a concentration of 10% fungus.

In the past decades, chemical fertilizers are used by farmers have numerous environmental impacts, including various types of water and soil contamination, and cause many problems to human health and other organisms. Sustainable agricultural policy and sustainable agricultural development have prompted experts to make greater use of soil organisms to meet the plant's nutritional needs, and that is why the production of biofertilizers began. Biological imbalances in the field of sustainable agriculture can be attributed to the fungi of myoderma and its species. According to various studies, it seems that this microorganism having high ability to compete for food and space, and the establishment of spores in the environment and in particular soil around the roots of most crops and non-farm and can induce plant resistance not only reduces pathogen agents Vermicompost is a microbiologically rich, nutrient-rich, organic modifier that is produced by the interaction between earthworms and microorganisms during the decomposition of organic matter. This type of organic fertilizer contains the waste of certain species of earthworms as a result of alteration, conversion, and relative organic residues as they pass through the digestive tract of these animals. Research has shown that vermicompost has a positive effect on growth, crop development, and crop yield. The aim of this study was to investigate the effect of different amounts of vermicompost and different concentrations of Trichoderma Bi isolate on different properties of celery.
This study was conducted to investigate the effects of Trichoderma and vermicompost as a biofertilizer promoting growth in research greenhouse at the Ferdowsi University of Mashhad with an average daily temperature of 15-27 °C and relative humidity of 40-70%. The present study was a factorial experiment based on a completely randomized design with three replicates as a pot experiment under no-tillage conditions in the greenhouse. The first factor consisted of four concentrations of Trichoderma harizianum isolate Bi: zero percent (control), 5%, 10%, and 15% volume of 50 liters of water consumed. The second factor also included four vermicompost treatments: zero percent (control), 25 percent, 50 percent, and 75 percent pot volume. Celery seeds were sown in transplant trays. The transplants were ready for transfer to the main litter after 10 weeks. The pots used were of plastic-type with a span diameter of 20 cm and a height of 25 cm. The plant media consisted of a mixture of 20% cocoon and 80% perlite, the roots of which were easily separable. After full harvest of plants at the commercial size, when a complete set of petiole sets was created (40 days after transplanting) morphological traits including the fresh and dry weight of roots and stems, a number of leaves, stem diameter, stem and root lengths were evaluated. The dry and dry weight of plant root was measured using a digital marking scale and with an accuracy of 0.01 g. Dry weight was determined after placing the specimens in the oven at 72 ° C for 48 hours. Also, the stem diameter was measured using a caliper machine with 0.01 mm accuracy. Root and shoot lengths were measured separately in the laboratory by a ruler in cm. Chlorophyll a, b and carotenoids were read at 663 nm, 653 nm and 470 nm for absorption by spectrophotometer, respectively. Data were analyzed using JMP8 software and ANOVA was performed using the LSD test at 5% probability level. Charts were drawn using Excel 2013 software.
The results of this study showed a positive and optimal effect of combined vermicompost and Trichoderma fungi. The highest shoot dry weight (49.23 g), leaf number (46), stem diameter (15 mm) and chlorophyll and carotenoid were observed in the effect of vermicompost and Trichoderma fungi compared to the control treatment. The main stem length (77.20 cm) was affected by the fungus with a 10% concentration at the highest rate compared to other treatments. Also, 50% vermicompost treatment had the highest root length (36.66 cm). The highest chlorophyll a was observed at 75% vermicompost interaction at 15% fungi concentration (10.02 mg / g fresh leaf weight). Application of vermicompost in the culture medium and application of Trichoderma fungus extract resulted in improved growth and yield. As can be seen in the results, the best treatment was 15% and 75% vermicompost, respectively. They can be used to improve plant growth and function. Many researchers believe that mainly isolates of Trichoderma produce biochemical stimuli to stimulate plant growth or reduce the inhibitory effects of certain compounds, biological and chemical toxins. According to available reports, the application of vermicompost with 30% volume in ornamental Lilium increased leaf area, fresh and dry weight of plant and plant height. So, fresh and dry weights of bean stem under vermicompost application significantly increased compared to the control treatment, which is in line with the results of this study. However, the researchers believe that the wet and dry weight gain of the plant body if used with vermicompost is probably due to the high amount of humic acids in this biofertilizer.
Based on the results of this study and other studies on vermicompost as an enriched fertilizer with numerous growth enzymes and hormones, as well as Trichoderma, it can be concluded that the use of bio-fertilizers plays an important role in the production of high-quality products. Also, the effect we find depends on the concentration used, but in the end, even their application at the lowest concentration compared to the control treatment increased growth and morphological characteristics of the plant. Overall, the results of this study showed that, in the case of the studied species, the combination of vermicompost and Trichoderma had a significant advantage over their separate application, and considering the superiority results of most traits at the time of application of these two together. Therefore, a combination of Trichoderma and vermicompost based on the results (concurrent use of 15% fungus extract and 75% vermicompost) is recommended to improve plant growth and yield.

  Spearmint is one of the plants that attracted the attention of researchers because of its economic and pharmaceutical importance. This plant is one of the most important and most famous species of mint which disperses in different parts of the world. One of the scarce resources that is affected by rainfall is water. The effect of water stress depends on the duration, durability and amount of deficiency. One of the most important factors limiting the growth of plants around the world is drought, which is the most common environmental stress. One of the most effective mechanisms that is used by plant in water stress condition is osmotic regulation. The accumulation of proline and soluble sugars (as the most important osmolite) in regulation of osmotic is done to dominate the negative effects of drought stress. Results of researches have shown that drought stress has effective effect on the growth and biochemical characteristic of plants, and it differs among different plants. Optimum plant nutrition is one of the effective methods for plant resistance in drought conditions. Humic acid is one of the most important fertilizers in the agriculture. It creates more space for water penetration by modifying physical soil characteristic and improving soil granulations. Humic acid increases the activity of photosynthesis by increasing the activity of the Robisco enzyme. To consider the high importance of spearmint as a valuable vegetable and medicinal plant, the aim of this study was to estimate the resistance of spearmint to different levels of drought stress and evaluate the effects of foliar application humic acid as a moderator factor in drought stress condition. A pot research was conducted in factorial experiment in a completely randomized design with 3 replications to investigate the effects of humic acid as a growth factor and moderator of the effect of drought stress, on Mentha spicata L. at the Faculty of Agriculture, Ferdowsi University of Mashhad. The first factor was three levels of drought stress (30, 70 and 100 % FC) and the second factor was four levels of humic acid (0, 100, 500 and 1000 mgL-1). At the firstly, spearmint rhizomes with 10 cm length were prepared with at least 2 buds. In the middle of March, about 4 rhizomes were cultivated in depth of 5 cm of pots soil. Foliar application of humic was used at three stages (one week before drought stress and one and three weeks after applying drought stress) on the plant surface. We didn’t use any humic acid on the control treatment. About 4 weeks after humic acid application, the morphological, physiological and biochemical traits were measured at flowering stage. Vegetative traits such as plant height, number of branches, leaf length, leaf width and fresh and dry weight of leaf and stem showed a significant decrease with increasing drought stress (70% of field capacity) in compared to control treatment. Foliar application of humic acid, especially 1000 mgL-1 improved these traits in compared to control plants in drought stress condition. Also, the mean comparison of the interaction treatments showed that the highest amounts of photosynthetic pigments was observed at 70% FC and application of 1000 mgL-1 of humic acid and the least one was belonged to control treatment and application of 500 mgL-1 of humic acid. The highest antioxidant activity of leaf extract (80.66%) and total phenol (0.87 mg/g fresh weight) were observed in plants treated with 1000 mgL-1 humic acid and 70% FC. The highest relative water leaf content was obtained at non-stress conditions (control) and the foliar application of 1000 mgL-1 of humic acid. This study showed that spearmint is very susceptible to drought stress, which could not withstand drought stress of 30% FC even for a short time. In general, means comparison of results showed that drought stress significantly reduced the morphological traits of spearmint. Also, the interaction treatments showed that the using of 1000 mgL-1 humic acid had the greatest effect on the growth indices. The highest amounts of photosynthetic pigments was observed at 70% FC and foliar application of 1000 mgL-1 of humic acid and the lowest one was belonged to control treatment of humic acid and without stress condition. Also, the highest levels of total phenol and antioxidant activity were observed in 70% FC and 1000 mgL-1 humic acid treatment. Therefore it can be stated that spearmint is high susceptible plant to drought stress because of sever effects of drought stress on its growth characteristics and physiological processes. The foliar application of humic acid, especially at high concentration (1000 mgL-1) can be effective in regulating the osmotic potential under slightly drought stress conditions. So, it can be used as an organic fertilizer in sustainable agriculture.