Evaluation of Growth Changes of Celery (Apium graveolens) under Treated, Vermicompost and Trichoderma harzianum BI

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.