فصلنامه گیاه و زیست فناوری ایران
سال شانزدهم شماره 2 (تابستان 1400)

The presence of abundant calcium carbonate and alkaline soil reaction in most of the country's soils has reduced the bioavailability of some elements for plants. The application of some soil amendments such as sulfur and organic matter can improve the nutrient status of the soil. For this purpose, a factorial experiment was conducted in a randomized complete block design with 18 treatments and 3 replications on the underground soil of walnut trees. The experimental factors included Thiobacillus at two levels (without inoculation and with inoculation), sulfur (S) at three levels (0, 1000 and 2000 kg. ha-1 ) and organic matter (OM) at three levels (0, 5 and 10 T. ha-1 ). The results showed that S treatment significantly affects soil pH (p <0.01), P (p <0.05) and iron (Fe) concentration on soils beneath the tree covers (p <0.05). The highest P concentration (9.06 mg / kg) and available Fe (6.34 mg / kg) was observed in the treatment of 2000 kg. ha-1 of sulfur. Organic matter treatment significantly has changed the soil pH (p <0.01), available Zn (p <0.01) and plant available P and Fe concentration in soils beneath the tree covers. As the level of applied OM increased, the soil pH decreased. The highest concentration of available P, Fe and Zn was observed in the treatment of 10 tons per hectare of OM. Inoculation with Thiobacillus bacteria decreased the soil pH and increased soil available P concentration. According to the results, the simultaneous application of S, Thiobacillus and OM can increase the phytoavailability of P, Fe and Zn in soils beneath the walnut trees.

A study to evaluation the effect of ascorbic acid and salicylic acid on growth indices and enzymatic activity of savory (Satureja hortensis L.) that Which is one of the useful medicinal plants and spices of the mint family, in a completely random statistical design with 7 treatments, 3 replication and each replication with 3 plant, a total of 63 plants, were done. Ascorbic acid and salicylic acid spraying each with 3 concentrations 50, 75 and 100 mg/l from the 4 to 6 leaf stage for three consecutive weeks and twice a week, were done. Distilat water sues as a control. Growth indices such as root and air fresh and dry weight, total chlorophyll content and catalaz, superoxide dismutase and peroxidase enzymes activity, were evaluated one week after the last spraying step. The results showed that the highest air fresh and dry weight, root dry weight, total chlorophyll content and proxidase enzymes activity in salicylic acid 100 mg/l treatment and the highest root fresh weight, catalaz, superoxide dismutase enzymes activity in ascorbic acid 100 mg/l treatment, were obtained. Therefore, according to the research results can be expressed that foliar application with different concentrations of ascorbic acid and salicylic acid improved the growth indices and enzymatic activity of savory (Satureja hortensis L.).

Pleurotus florida is an edible mushroom with a high potential for removing oil pollutants. In this study, the effect of gas oil on pin creating and amino acids content was investigated. The gas oil concentrations were used 2.5- 10% and for 30 days.The results showed that gas oil has a positive effect on the pinning stage, and increasing its concentration increases the number of pins. Increasing the concentration of gas oil in the treatments reduced the water consumption pattern. The highest consumption of the aqueous phase belonged to the control sample. Seventeen amino acids were evaluated. The study of amino acids showed that the growth of fungi in gas oil-contaminated environments causes a significant increase in the content of amino acids (15 amino acids). The amino acid hydroxyproline was not reported in the selected gas oil treatment sample. According to these findings, P. florida can be considered as a safe species, with fast growth and resistance to petroleum pollutants for simultaneous removal of contaminants and the use of biomass to produce the required amino acids in the industry.

This experiment was conducted to investigate the effects of different levels of oregano extract (OE) o performance in broiler chickens. A total of 360 male chicks in a completely randomized design with 5 treatments, 4 replicates of 16 birds were distributed and reared under experimental same conditions. During experimental period (1 d until end period), drinking water of the control group had no any additive while antibiotic (0.0125 % Erythromycin), 1.5, 3 or 4.5% OE were added respectively to other 4 experimental groups. The findings indicated that the use of OE affected significantly feed intake, body weight gain and feed conversion ratio in broiler chickens. In 11-24 d period, the highest feed intake was obtained in groups fed 4.5% OE or antibiotic. Also in this period, feeding 3 or 4.5% OE or antibiotic to broilers caused the significant highest weight gain (P<0.05). in overall period, using 4.5% OE caused significantly the highest weight gain and also, 3 and 4.5% OE significantly decreased feed conversion ratio in broiler chickens. In conclusion, using OE especially in level of 4.5% in broiler drinking water has beneficial effects on performance parameters and therefore can be applied as a suitable replacement for antibiotic in broiler chickens.

This study was performed to investigate the effect of mycorrhizal fungus and different levels of humic acid (zero, 200 and 400 mg/l) and salicylic acid (zero, 100 and 200 mg/l) on morphological characteristics and essential oil content of three cultivars Lemonella, Citronella and Varigated. Lemon balm (Melissa Officinalis L.) was implemented in 1397 in a greenhouse in northern Iran. The experiment was performed as a factorial in a completely randomized statistical design with 3 replications. Mycorrhiza and humic acid treatments were applied at the time of seed sowing and salicylic acid solution was sprayed in two stages (second and third weeks of pot cultivation). The results of this experiment showed that all treatments had a significant effect on fresh and dry weight of shoots and roots, root volume and essential oil content and among the lemon balm cultivars Lemonella cultivar had the highest morphological characteristics and essential oil content. The highest shoot dry weight, fresh and dry root weight and root volume in mycorrhiza+ humic acid 400 mg/l + salicylic acid 200 mg/l and the highest fresh weight of mycorrhiza+ humic acid 200 mg/l + salicylic acid 200 mg/l was obtained. Also, the highest amount of essential oil was observed in the treatment of mycorrhizal fungus+ humic acid 400 mg/l + salicylic acid 100 mg/l. In general, to improve the vegetative growth and the amount of essential oil of lemon balm, the application of Lemonella cultivar and application of mycorrhizal fungus with humic acid 400 mg/l and salicylic acid 200 mg/l is recommended.

Food security means ensuring that the public has access to adequate, healthy and nutritious food. Increasing population and subsequent increase in demand requires increasing production per unit area. On the other hand, the area of arable land has decreased due to various factors such as drought, increasing soil salinity and urban development. For example, upsetting the balance of nutrients, reducing the quantity and quality of the product, the accumulation of heavy metals such as boron, cadmium, lead, etc. in the plant can be mentioned. other problems can include reduced absorption of elements and micronutrients by the roots, destruction of soil structure, pollution of surface and groundwater, reduced population of soil organisms and so on. While organic farming is one of the sustainable agricultural strategies that is based on natural methods of pest and disease control and the use of pesticides and artificial herbicides, chemical fertilizers, hormones and antibiotics to It is forbidden as much as possible. Therefore, in recent decades, many efforts have been made at the international level to move towards sustainable development.