In order to investigate the effect of mycorrhiza and surfactant on forage characteristics of corn (Zea mays L.) under deficit irrigation condition, a split plot factorial experiment was conducted in a randomized complete block design with three replication at the Research Farm of Agricultural College, Shahed University, Iran in 2016. The experimental treatments included irrigation at three levels of 30, 60 and 90 percent available soil water depilation as a main factor and inoculation with mycorrhizal fungi (Glomus etunicatum, G. intraradices and G. mossea) at two levels (inoculation and no inoculation with mycorrhizal) and treatment of surfactant solution containing two levels (Application of surfactant and non-use of surfactant solution) as sub factors. Results showed that with increasing depletion of available soil water, application of mycorrhizal fungi increased crude protein percentage (CP), water soluble carbohydrate (WSC) and acid detergent fibre (ADF), increased by 39.24, 30.64 and 39 percent respectively. Application of surfactant on percentage NDF was not significant. As deficit irrigation stress increased, dry weight of forage decreased and highest dry weight of forage (400 gr/plant) was observed under normal irrigation conditions and application of surfactant and mycorrhiza. The results also showed that by increasing the amount of available water discharge, application of surfactant and inoculation with mycorrhizal fungi increased water use efficiency 97 percent in compare to control.

In order to investigate the effect of row spacing on yield and growth of cotton cultivars uncer two conditions of fertilizer application and non-fertilization, a study was conducted in Gorgan as a split-factorial experiment based on randomized complete blocks design with three replicates in 2017. Experimental factors included three cotton cultivars (Sajedi, Kashmar and Golestan), row spacing at two levels (20 and 80 cm) and nitrogen, phosphorus and potassium fertilizers application at 350, 300 and 225 kg ha-1 and control treatment (No fertilizer), respectively. According to the results of analysis of variance, the effect of cultivar on number of reproductive branches and bolls as well as the height of first boll from ground was significant, whereas row spacing significantly affected number of vegetative branches and bolls, the height of first boll from ground, boll weight and lint yield. In all three cultivars studied, decrease in row spacing led to decreased plant height and increased leaf area index, dry matter and lint yield. Fertilization led to significant increase in plant height, leaf area index, number of reproductive branches and bolls, boll weight and yield. Among interactions, only the interaction of cultivar× row spacing on number of reproductive branches and interaction of row spacing× fertilizer on boll number, boll weight and lint yield were significant. Therefore, there is a significant interaction between row spacing and nutrient consumption in terms of growth characteristics and yield of cotton cultivars, and decreased row spacing in cotton can significantly increase lint yield.

This study was conducted to evaluate the factors limiting wheat yield in Kalaleh County using the Comparative Performance Analysis (CPA) method in 2015-16. Collection of the required information was done by fieldwork, and personal interviews with farmers. To this aim, 60 wheat fields in dry land areas of Kalaleh were selected to have sufficient diversity in all crop management, planting, crop protection and harvesting. The amount of grain delivered to the wheat shopping centers was recorded after determining the amount of drop as the final yield of the farm. The CPA was used to determine the yield gap and identify the factors that caused it. The results of yield model showed that there was a difference of 4071.7 kg between achievable (7248 kg/ha) and actual yield (377.4 kg/ha). Among studied variable, the farmer experience, seeding rate, the amount of phosphorus in soil, frequency of use of fungicide, organic matter of soil, amount of potassium absorbed in soil and amount of applied nitrogen had the most influence on wheat yield gap in the study area, which were 19.4, 16.8, 14.9, 14.3, 12.7, 11.7 and 10.3 percent of the achievable yield. By amending these factors, it seems that it could reduce the difference between achievable yield and actual yield.

To evaluate the impact from the interaction of nitrogen and herbicides on weed control of maize along with the yield and yield components of maize, an experiment has been conducted in a randomized completer block design as factorial arrangement with three replications at Tarbiat Modares University. The first factor includes nicosulfuron (2 l.ha-1), 2,4-D+ MCPA (1.5 L.ha-1), weed-infesting, and weed free (hand hoeing) as control. The second factor is application of 350 kg.ha-1 nitrogen from urea source and no nitrogen application as control. Results indicate that application of nitrogen boosts nicosulfuron efficacy in controlling broad- and narrow-leaved weeds, though it does not affect 2,4-D+ MCPA efficacy in controlling broad-leaved weeds. The application of herbicide and nitrogen has no significant effect on corn yield components, but the number of grains per row increase significantly when both nicosulfuron and nitrogen are applied together. Application of nicosulfuron and nitrogen increases the grain yield by 94%, compared with sole application of nicosulfuron. Application of both nitrogen and 2,4-D+ MCPA has no effect on corn grain yield. Results show that the application of nicosulfuron and nitrogen can be the best option for satisfactory weed control and maximum grain yield in the corn.

To investigate the physiological responses of sesame cultivars to the application of nano magnesium and chitosan biopolymer under different irrigation regimes, a split factorial based on randomized complete block design has been conducted with three replicates between 2017 and 2018. The irrigation cut-off, based on BBCH scale, has served as the main factor (normal irrigation, irrigation up to 50% flowering, and seed ripening), with the sub factors including Oltan and Dashtestan-2 sesame cultivars, and nano magnesium (application and non-application) and chitosan (control, 4.8, and 6.4 g.L-1). The highest mean grain yield belongs to the application of 6.4 g.L-1 chitosan under normal irrigation with an average of 1235.1 kg.ha-1. Also, the highest total chlorophyll content is observed in Dashtestan-2 genotype under normal irrigation with a mean of 24.7 mg.g-1 FW and the lowest mean have been obtained in both genotypes under irrigation up to 65 BBCH with a mean of 17.21 and 17.46 mg.g-1 FW, respectively. Application of nano fertilizer in Oltan genotype under irrigation up to 65 BBCH increases the catalase activity by 41.11%, compared to the control treatment. The highest activity of ascorbate peroxidase has been achieved when not applying chitosan under irrigation conditions up to 65 BBCH. It has risen by 55.06%, compared to the control treatment. In general, the results show that irrigation up to 65 BBCH reduces grain yield, in turn alleviated by the negative effects of stress on magnesium and chitosan nanoparticles (9.93% and 27.46%, respectively). Based on the regression analysis results, four traits, namely chlorophyll b, total chlorophyll, proline, and catalase, enter the model that explains 42.11% of the total grain yield variations. Results of simple correlation between traits and regression analysis indicate the indirect effects of physiological traits on grain yield and among the studied parameters, photosynthetic pigments has been of high account in stress conditions.

The present study aims at evaluating the effects of leaf foliar of growth regulators and nitrogen on growth parameters and yield of spring safflower. To do so it has carried out a research at East Azerbaijan Agricultural Research Center as a factorial experiment based on RCBD (Randomized Complete Block Design) with three replications. The factors include growth regulators in four levels, namely auxin, cytokinin, auxin + cytokinin (wherein the treatment’s concentration has been 1000 mg/L), and control (no use of growth regulator, whatsoever), foliar application of nitrogen (3 and 6 per thousand), and two springcultivars (Soffe and Goldasht). Results show taller plants (17%) and greater number of heads per plant (39%), seeds per head (9%), and lateral stems (37%) for Soffeh cultivar, compared to Goldasht variety. On the other hand, Goldasht cultivar provides the maximum head diameter (15%) and 1000 seed weight (47%), in comparison to Soffeh cultivar. The maximum grain yield is observed for Soffeh cultivar with auxin growth regulator and a concentration of three per thousand foliar application of nitrogen (3205 kg ha -1),displaying no significant difference from either the control or the application of three per thousand foliar of nitrogen (3120 kg ha-1). The application of growth regulators has changed the fatty acid composition. The application of auxin + cytokinin as the growth regulator with a concentration of three and six per thousand foliar of nitrogen increase the oleic, palmitic, and linolenic acids. However, the use of auxin and cytokinin separately increase linoleic and stearic acids among the fatty acids, compared to the control, which is higher in Soffeh cultivar than Goldasht. In general, Soffeh cultivar shows higher growth and yield, compared to Goldasht cultivar, indicating the positive effect in foliar application of hormones and nitrogen for the latter. 

In order to investigate the effects of foliar application of 6-benzylaminopurine on physiological traits, yield and yield components of quinoa (cultivar Q26) an factorial experiment has been conducted, based on randomized complete block design with four replications at the research farm of Agriculture Faculty, the University of Zanjan, during cropping seasons of 2017. The experimental factors include optimal irrigation (-0.4 MPa) and drought stress (-1.5 MPa) as primary factor and foliar 6-benzylaminopurine in three levels (0, 50, and 100 μM) as the secondary one. Irrigation treatment has significant effect on all traits, except chlorophyll b and cartenoide. Drought stress increases electrolyte leakage (EL), proline, and Harvest index (HI) though it has a declingin effect on other traits. The effect of irrigation and hormone interaction has been considerable, except for chlorophyll b, total chlorophyll, thousand weight grain, and biomass yield. The highest grain yield (215.75 g.m2) in optimal irrigation is observed in 50 μM and in drought stress condition with 149.76 g.m2, obtained in 100 μM of cytokinin. The maximum harvest index (25.6%) can be observed in the control treatment of drought stress. Results show that applying cytokinin reduces the unfavorable effects on quinoa; therefore, this hormone’s foliar can be a solution to enhance the grain yield of quinoa under drought stress conditions.

In the fields around Golestan dam, crop rotation is not performed, putting the soil fertility at risk. This experiment aims at evaluating the nutritional status of the region’s soils and determining the need for fertilizer with emphasis on macronutrients. The fertilizer requirement of these soils in 2017-2018 has been determined, using the QUEFTS model. At first, 30 fields in the Golestan dam region, irrigated by the dam itself, have been chosen. In each field, a small section has been selected as a non-fertilized one. All agronomic practices have been done in accordance with conventional farmers' method. From each field (fertilized and non-fertilized), five one-meter squared quadrats have been used to cut off the crop and the grain yield and non-grain yield, and measure its N, P, and K concentration. Results reveal that the mean value of N, P, and K uptake by shoots have been 54, 19.5, and 98 kg/ha, respectively, with the average grain yield being 4150 kg/ha in farmers' field. For 1000 kg of grain production per hectare, one requires 13, 4.5, and 22 kg of  N, P, and K, respectively. Therefore, according to the proper validation results of the QUEFTS model, it is recommended to apply 325 kg/ha urea fertilizer, 195 kg/ha triple super phosphate fertilizer, and 60 kg/ha potassium sulfate fertilizer to produce about 5000 kg/ha wheat grain in this area.

In order to study the effects of various rates of starter nitrogen, methanol, and bio fertilizers on nodulation, grain filling period, and yield of lentil (Lens culinaris L.) under rainfed condition, an experiment has been carried out as factorial based on randomized complete block design with three replications under field condition in Ardabil in 2018-2019. The factors include starter nitrogen in three levels (no nitrogen and N application of 25 and 50 kg/ha) by urea, bio fertilizers in four levels (without bio fertilizers, application of Rhizobium legominosarum, mycorrhiza and both application of mycorrhiza with Rhizobium legominosarum), application of methanol at three levels (foliar application with water and methanol applications of 15 and 30 volume percent). Means comparision show that the maximum  number and weight of nodules per plant (12.72 and 11.59 mg per plant, respectively), grain filling rate (1.45 mg/day), grain filling period and effective grain filling period (35.17 and 29.91 days, respectively), number of pod per plant (34.43), and grain yield (1530 kg/ha) have been obtained at both applications of mycorrhiza with Rhizobium legominosarum, foliar application of 30 volume percent of methanol, and 50 kg/ha of starter nitrogen. The treatments display an increase of about 210%, 25.64%, 45.76%, and 103% in the number of nodules per plant, grain filling rate, effective grain filling period, and grain yield, respectively, in comparison with the control (no application of nitrogen, methanol, and bio fertilizers). Based on the results from this study, both applications of bio fertilizers (mycorrhiza with Rhizobium legominosarum) and foliar application of 30 volume percent of methanol with 50 kg/ha starter nitrogen are recommended to improve grain yield of lentil under rainfed condition.

Foeniculum vulgare Mill. is one of the medicinal plants, which is widely used in pharmaceutical and food industries. Due to the effective role of micronutrients in the quantitative and qualitative yield of medicinal plants, the effect of foliar application of iron chelate (0, 1.5 and 3 g/L) and zinc chelate (0, 1.5 and 3 g/L) on the functional properties and essential oil content of native and improved (cv. Soroksari) fennel was evaluated. The experiment was conducted as a split-split plot, based on RCB design with three replications during 2018 at the University of Kurdistan. Simple effects of iron chelate, the interaction iron chelate and cultivar, as well as the interaction iron chelate, zinc chelate and cultivar type, had no significant effect on measured traits. Zinc chelate significantly affected most of the studied traits, so that the highest of essential oil content (5.06%) and yield (35.07 L/ha) were belonged to 3 g/L treatment, while the highest seed yield (884.2 kg/ha) was obtained in zero treatment of zinc chelate. The interaction of iron chelate and zinc chelate as well as the interaction of zinc chelate and cultivar had only a significant effect on seed width and number of umbels, respectively. The impact of cultivar had a significant effect, on the number of umbels per plant, seed yield, and essential oil yield, so that the highest average of mentioned traits (25.29, 765.26 kg/ha and 34.27 L/ha, respectively) were belonged to native fennel. Generally, among the fertilizer treatments, 3 g/L zinc chelate and between the two types of fennel, native fennels were recognized as superior.

The purpose of the present study is to evaluate the effects of different levels of vermicompost on quantity and quality of Lilium longiflorum LA hybrid cv. Dynamix, in a completely randomized design with 5 treatments and 3 replications. The treatments include 0 (control), 20%, 35%, 50%, and 65% of vermicompost pot (V/V) in 70% cocopeat and 30% perlite of bed culture under greenhouse conditions. Once the buds’ color change from bold green to colorless green, cut flowers are removed from various treatments and the flower’s inflorescence is studied in the laboratory. Results show that fresh weight of Lilium in low-level vermicompost surpass the other treatments, especially the 20% one. Qualitative parameters such as chlorophyll, protein leaf, anthocyanin, and total soluble solid of the petal have had a significant increase in all vermicompost treatments, compared to the control. Overall result examination of this study indicates the 20% vermicompost treatment has been more suitable, thanks to its superior moisture preservation at plant shoots as well as the improvement of some morphologic traits like the number of flowers as well as addition of leaf area, which contributes to the cultivation of better quality Lilium LA hybrid flower.

Sunburn is one of the important factors, limiting pomegranate production, especially in regions with hot summers. Since exogenous application of kaolin can increase tolerance to some environmental stresses by improving metabolic pathways and increasing net photosynthesis, this paper studies the effect of kaolin spraying on some pomological and biochemical characteristics of commercial pomegranate cultivars in Rijab region (Kermanshah province). Accordingly, it carries out a factorial experiment, based on a RCBD, which is consisted of three concentrations of kaolin (i.e., 0 (distilled water), 3%, and 6%) as well as two pomegranate cultivars (Malas Torsh & Yosef-Khani) with three replications. Results show that in both cultivars, kaolin treatment at 6% concentration improves fruit weight, the length and width of aril and fruit, aril weight, and the yield. In addition, fruits of both pomegranate trees with kaolin treatment at both concentrations, especially at 6% concentration, show increased soluble solids, fruit juice, and total phenol content. Despite the different morphological and biochemical reactions in the two cultivars, one of the cultivars could be used in accordance to different purposes and conditions. In addition, a high concentration of kaolin reduces sunburn and cracking of pomegranate fruits in both cultivars, increasing yield per hectare. This treatment can serve as a suitable method to reduce physiological disorders in pomegranate growing areas such as Rijab region.