This study was conducted to investigate the effect of Potassium Thiosulfate and Nitrate fertilizers on yield, water use efficiency and control of tuber cracking of potato cultivars. This research was conducted Factorial based on randomized complete block design with three replications at the National Potato Research Station located in Ardabil during 2021. The first factor includes Potassium Thiosulfate at three levels (zero, 10 and 20 liters per hectare with irrigation water), the second factor contains Ammonium Nitrate at three levels (based on soil test, 30% and 60% more than soil test) and third factor included four potato cultivars (Agria, Savalan, Anusha and Takta). The results showed that there was a significant difference between the levels of Potassium Thiosulfate fertilizer, cultivars, interaction effect of Potassium Thiosulfate fertilizer and Nitrogen fertilizer and tripartite interaction of Potassium Thiosulfate fertilizer, Nitrogen fertilizer and cultivars in terms of tuber yield, tuber number and weight per plant, plant height, main stem number per plant, water use efficiency, mean of number, length, width, depth and surface of tuber cracking. The highest tuber yield, tuber weight per plant and water use efficiency in the treatment of Potassium Thiosulfate fertilizer 10 liters per hectare and Nitrogen 250 and 328 kg.ha-1 in Takta cultivar, Potassium Thiosulfate fertilizer 10 liters per hectare and Nitrogen fertilizer 400 kg.ha-1 in Savalan cultivar and 20 liters per hectare of Potassium Thiosulfate fertilizer and 328 kg.ha-1 of nitrogen were observed in Savalan cultivar. Based on the results of factor analysis, in the treatment of zero liters per hectare of Potassium Thiosulfate fertilizer and 328 kg.ha-1 of Nitrogen fertilizer of Takta and Savalan cultivars; in the treatment of 10 liters per hectare of Potassium Thiosulfate fertilizer and 250 kg.ha-1of Nitrogen fertilizer in Takta and Agria cultivars, 328 kg.ha-1of Nitrogen fertilizer in Takta cultivar and 400 kg.ha-1 Nitrogen fertilizer in Anusha, Takta and Savalan cultivars and 20 Potassium Thiosulfate fertilizer per hectare and 250 kg.ha-1 Nitrogen fertilizer in Takta cultivar and 328 kg.ha-1 Nitrogen fertilizer in Savalan cultivar had the highest values in terms of tuber yield, tuber number and weight per plant, plant height and water use efficiency. Based on the results of cluster analysis, the fourth group includes treatments of 10 liters per hectare of Potassium Thiosulfate fertilizer and 250 and 328 kg.ha-1 of Nitrogen fertilizer in Takta cultivar and 400 kg.ha-1 of Nitrogen fertilizer in Savalan cultivar and 20 liters per hectare of Potassium Thiosulfate fertilizer in 328 kg.ha-1 of Nitrogen fertilizer in cultivar was in Savalan cultivar and in terms of tuber yield, tuber number and weight per plant, plant height, water use efficiency had the highest amount and without the number of tubers with crack in the plant.

Guar is an annual plant that tolerates salinity and drought from the legume family, which can be used as an alternative product in low water plains. Considering the characteristics of the guar, such as having the ability to biologically nitrogen fixation and a relatively deep root system, high adaptability to drought and poor soils, high competitive power and favorable morphology, it seems that placing it in intercropping cultivation, it can increase the efficiency of final yield of intercropping crops. Utilizing the intercropping system for plants, is an effective measure to improve soil fertility, increase the absorption of nutrients and improve the efficiency of water consumption, and it is considered one of the most important scientific methods to help maintain the stability and balance of the living system of the soil. Therefore, this research was carried out with the aim of comparing different patterns of intercropping cultivation of guar next to the roselle with its pure cultivation at different levels of nitrogen fertilizer in field of Toos Planting Manager Company in Taybad city, located in Polband plain. The experiment was performed as a split plot in the form of a randomized complete block design with two factors and in three replications. The first factor included eight ratios of mixed crops, which were implemented as follows: sole cultivation of guar, one row of guar + one row of roselle, two row of guar + one row of roselle, three row of guar + one row of roselle, one row of guar + two row of roselle, one row of guar + three row of roselle, two row of guar + three row of roselle and Three row of guar + two row of roselle. The second factor included nitrogen fertilizer, based on recommendation of the soil laboratory, at three levels: without giving nitrogen fertilizer (zero kg per hectare) and 50 and 100 percent of guar's requirement for nitrogen, one half at the time of planting and the other at the time of pod formation. The results indicated a significant superiority of sole cultivation of guar treatment in 100 percent of guar's requirement for nitrogen fertilizer in terms of the number of pods per plant and the number of seeds per pod. Nevertheless, in attributes of pod length and weight of 100 seeds, significant superiority changed in favor of treatment of three row of guar + one row of roselle under conditions of 100 percent of guar's requirement for nitrogen fertilizer. In attributes of shoot dry weight and seed yield, the two treatments of sole cultivation of guar and three row of guar + one row of roselle in condition of providing 100 percent of nitrogen fertilizer requirement have a significant advantage and were placed in a statistical group. Based on the results of this research, in terms of shoot dry weight, yield components and seed yield, the only treatment that was in the same statistical group with sole cultivation of guar or had a small statistical difference with it, is the treatment of three row of guar + one row of roselle in the condition of supplying 100 percent of nitrogen fertilizer requirement. Therefore, it seems that this intercropping combination is recommendable for farmers who like this type of planting system. Because doing intercropping for species with different phenology can increase the productivity of agricultural lands while creating biodiversity and guaranteeing production. Also, according to the findings of present research, the reduction of nitrogen fertilizer consumption to less than requirement of guar was effective in reducing the yield and its yield components. Therefore, it is recommended to use full nitrogen fertilizer based on recommendations of the soil laboratory.

AbstractTo investigate the effect of irrigation frequency and nitrogen fertilizer on the yield of two red bean genotypes, an experiment was carried out in the form of factorial split plots of completely randomized blocks with four replications at the research field of University of Tehran in 2016. The main factor included the irrigation cycle (7 days customary in the region, once every 11 and 15 days), nitrogen fertilizer required by the plant (zero or control, 50% and 100% nitrogen) and red bean cultivars (Akhtar and D81083) as sub-plots. The results showed that the irrigation cycle significantly decreased plant height, number of pods per plant, number of seeds per pod, kernel weight, biological yield, seed yield and harvest index. The use of nitrogen fertilizer also significantly increased the values of other traits except the number of seeds per pod. Akhtar cultivar had the highest plant height and total dry matter, while the highest seed and biological yield was observed in D81083 line. The interaction of irrigation cycle and nitrogen fertilizer on 100 seed weight and harvest index was significant. The highest water consumption efficiency (0.44 kg/m3) was obtained in the 7-day irrigation treatment with 100% nitrogen fertilizer in D81083 genotype, but the highest nitrogen consumption efficiency was obtained in 50% nitrogen fertilizer (12.5 kg seeds per fertilizer unit) and in higher nitrogen consumption, despite the noticeable increase in grain yield (3%), nitrogen consumption efficiency decreased by about 41% and water consumption efficiency decreased by about 5%.IntroductionIran has a dry and semi-arid climate, and water shortage is one of the basic problems of agriculture, and two-thirds of the agricultural lands are located in semi-arid and dry regions. Drought is one of the most destructive environmental stresses that reduces the performance of crops, especially beans, more than other environmental stresses. In an experiment on beans, it is reported that between different levels of nitrogen (zero, 45, 90 and 135 kg of urea per hectare), a significant difference was observed in terms of yield, and with increasing nitrogen application, grain yield per unit area increased. So that the highest seed yield was obtained with an average of 3144 kg. ha-1 with the consumption of 135 kg and the lowest yield with an average of 1986 kg. ha-1 with the consumption of 45 kg of urea fertilizer per hectare. The yield difference between different levels of urea was attributed to the effect of nitrogen in increasing the number of pods and the average weight of 1000 seeds. Therefore, considering the importance of the role of drought as one of the most important stresses faced by the plant and its effect on reducing the amount of production, as well as the need to use nitrogen fertilizer for its biological stabilization, in order to achieve acceptable yields, this research was conducted with the aim of It is necessary to identify the effect of different levels of irrigation and nitrogen alone and together on bean yield, to determine the efficiency of water and nitrogen consumption under water stress conditions, and to determine the most important fertilizer treatment required by beans under water stress conditions.Material and MethodsTo investigate the effect of irrigation frequency and different levels of nitrogen fertilizer on the yield and yield components of two genotypes of red bean, an experiment was conducted in the form of factorial split plots in the form of completely randomized blocks with four replications in the research training farm of Tehran University of Agriculture and Natural Resources Campus (Karaj).), was implemented in the crop year 2015. The experimental factors include the irrigation cycle (7 days customary in the region, once every 11 and 15 days) as the main factor, the nitrogen fertilizer required by the plant (zero amount (control), 50% and 100% nitrogen consumption) and red bean varieties (Akhtar and D81083) were considered as sub-plots.Result and DiscussionIn general, the results of this study showed that increasing the frequency of irrigation (more than once every 7 days) significantly led to a decrease in growth traits and finally a decrease in seed yield in red bean cultivars. On the contrary, increasing the use of urea nitrogen fertilizer led to the improvement of growth traits such as the amount of dry matter produced per unit area, harvest index and finally improved the components of yield and grain yield. In addition, in relation to the effect of different levels of nitrogen, the highest grain yield (2777 kg. ha-1) was obtained in 100% required nitrogen fertilizer, and since the yield corresponding to this treatment with the yield corresponding to 50% nitrogen fertilizer consumption There was no significant difference and due to the fact that the highest agricultural efficiency of nitrogen consumption was obtained at 50% nitrogen and the lowest at 100% nitrogen consumption, also the highest efficiency of nitrogen consumption was obtained in normal irrigation and the lowest of this trait. It was obtained under severe water deficit stress (15-day irrigation cycle). Therefore, in order to reduce environmental damage, it is recommended to use a lower amount of nitrogen fertilizer in the conditions of water shortage stress or drought stress, but in conventional irrigation without stress, it is better than 100% of nitrogen fertilizer required by the plant to achieve a higher harvest index. be used. In relation to the comparison of red bean cultivars, it was observed that the D81083 line had a higher grain yield (2729 kg. ha-1) than the Akhtar variety (2514 kg. ha-1), so that the rate of yield reduction and harvest index of the D81083 line under water stress conditions was lower than It was Akhtar's figure. In order to make optimal use of limited water resources, the use of D81083 line seems desirable for cultivation in similar conditions in this region due to its earlier maturity and higher dry matter production.

Canola (Brassica napus L.) is an oilseed crop, which due to the high percentage and quality oil, extending of its cultivation is of interest. Nitrogen is one of the most important nutrients and the key factor to achieve optimal yield in rapeseed. Considering nitrogen leaching in the soil and resulted environmental pollution, the use of biofertilizers, especially nitrogen-fixing bacteria, play an important role in enhancing nutrient uptake and nitrogen use and uptake efficiencies. Therefore, the aim of this research was to investigate the improvement of absorption of macronutrients and nitrogen efficiency indicators under the influence of chemical and biological nitrogen fertilizer management. A field experiment as split plots based on a randomized complete block design with three replications was conducted at the research station of the Faculty of Agriculture, Yasouj University located in Deshtrum in 2019. The main factor was nitrogen fertilizer at 6 levels (zero, 25, 50, 75, 100 and 125 kg ha-1 of pure nitrogen from the urea source) and the sub factor was biofertilizer containing Azotobacter and Azospirillium bacteria at two levels (application and non- application). The uptake of nitrogen, phosphorus and potassium nutrients in seeds and shoot was measured and the nitrogen efficiency indices were calculated. The highest seed nitrogen, phosphorus and potassium percentage obtained from the combined application of nitrogen fertilizer + bacteria. The combined application of chemical and biological nitrogen fertilizer increased grain yield. The highest seed yield (8790.60 kg ha-1) was obtained in the treatment of 125 kg ha-1 of nitrogen and the application of biofertilizer. The nitrogen use efficiency decreased with the increase of nitrogen levels, and the maximum (40.92 kg ha-1) was obtained from the treatment of no application of bacteria and also nitrogen. The nitrogen uptake efficiency increased significantly with the use of nitrogen fertilizer and the use of bacteria. The maximum nitrogen remobilization (89.79%) was obtained from the application of 125 kg ha-1 of nitrogen and no application of biofertilizer, and the lowest was obtained from the treatment of no application of nitrogen and application of biofertilizer (74.46%). Considering the superiority of the 125 kg ha-1 of nitrogen along with biofertilizer in terms of seed yield and percentage of absorbed nutrients, it seems that these amounts of nitrogen fertilizer with the use of biofertilizer are recommendable to achieve proper yield in the examined and also similar areas. Also, the results showed that for most of the investigated traits, applying biofertilizer could reduce the consumption of chemical nitrogen fertilizer by supplying some part of the nitrogen (ca. 50 Kg/ha) needed by canola.

The aim of this study was to evaluate the tillage and fertilization methods of sesame plants with respect to the impact of water deficit stress conditions in the years (2022-2023). The experiment was performed as a split plot in the form of a randomized complete block design with three replications. The main factors included three tillage methods (no tillage, low tillage and conventional tillage), the sub-factor of two irrigation levels (normal and low irrigation) and the sub-factor of four fertilization methods (no fertiliser, nitrogen fertiliser, vermicompost and combination of nitrogen and vermicompost). The results showed that the reactions of the traits to water deficit stress were different in different combinations of fertilizers and tillage. In 2022 the reduction of grain yield in different treatments ranged from 14.3% (low tillage with combined nitrogen fertilizer and vermicompost) to 23% (conventional tillage without fertilizer). In 2023 the decrease in grain yield was between 9.8% (low tillage with integrated fertilizer) and 20% (conventional tillage without fertilizer). In both years, the least negative effect was observed in the low tillage treatment with combined nitrogen fertilizer and vermicompost and the highest negative effect was observed in the conventional tillage treatment without fertilizer. Treatments without tillage and treatments with separate application of nitrogen fertilizer or vermicompost showed moderate results. Based on the results of this two-year study, the use of low-tillage method along with the combined application of nitrogen fertilizer and vermicompost is recommended for managing sesame fields in water-limited conditions.

The simultaneous application of nitrogen fertilizer and growth regulators in rainfed conditions improves plant growth and development parameters. For this reason, research was conducted in two regions in the crop years of 2022-2023 in Poldokhtar and Khorram Abad cities. The experiment was carried out as a factorial design in the form of a basic randomized complete block design with three replications. The first factor includes four levels of nitrogen chemical fertilizers, including 0, 50, 100 and 150 kg.h-1 urea, and the second factor was foliar application of blank (spraying solution with distilled water), paclobutrazol (120 mg/liter), spermidine (1 mM), and chlormequat chloride (three grams per liter). The highest seed yield was observed in the treatment of 100 kg.h-1nitrogen fertilizer and paclobutrazol foliar spraying at the rate of 2686.4 kg/ha, and the lowest rate was obtained in the absence of nitrogen fertilizer and no foliar spraying at the rate of 1284.8 kg/ha. The highest protein yield was observed in the treatment of 100 kg.h-1 nitrogen fertilizer and paclobutrazol foliar spraying at the rate of 313.25 kg.h-1. The highest total chlorophyll was observed in the treatment of 100 kg.h-1 nitrogen fertilizer and paclobutrazol foliar spraying at the rate of 10.38 mg/g of fresh weight. According to the results of this study, the use of nitrogen fertilizer and foliar application of growth regulators can significantly improve the growth, yield and photosynthetic pigments of barley in rainy conditions.

Lemongrass (Cymbopogon citratus (DC.) Stapf), a perennial plant from the Gramineae family, is renowned for its rich polyphenol compounds, having significant medicinal, cosmetic, and culinary applications. Enhancing the quantitative and qualitative yield of lemongrass is of considerable economic importance. Salicylic acid, a key regulator of physiological and biochemical processes, acts as an elicitor to enhance the accumulation of secondary metabolites in plants. Similarly, nitrogen plays a vital role in plant growth, improving yield quantity and quality. This study investigated the effects of nitrogen fertilizer and salicylic acid on various quantitative and qualitative traits of lemongrass. A factorial experiment based on a randomized complete block design was conducted in 2021 at the Agricultural Sciences and Natural Resources research farm of the University of Khuzestan, Ahvaz, Iran. The experiment evaluated the effects of different levels of salicylic acid (0, 10 µM, and 100 µM) and nitrogen fertilizer (0, 50, 100, 150, and 200 kg/ha from a urea source) on lemongrass. Each treatment was replicated three times. In each fertilizer treatment, 20% of the nitrogen was applied after plant establishment, with the remainder applied in four stages alongside irrigation water to minimize leaching losses based on soil nitrogen content. Salicylic acid was applied via foliar spraying using a backpack sprayer when 70% of each plot was covered by lemongrass, with a second application 15 days later. Each plot measured 3 meters in width with six planting lines, each 3 meters long, 60 cm apart, and plants within lines were spaced 40 cm apart. The soil had a silty clay texture, pH of 7.5, and electrical conductivity of 2.6 dS/m. The studied traits included chlorophyll a, b, and total chlorophyll, carotenoid content, total fresh and dry weight, antioxidant activity percentage, total phenol content, and essential oil percentage and yield. The interaction between salicylic acid and nitrogen fertilizer significantly influenced all studied traits except antioxidant activity percentage. Nitrogen fertilizer alone significantly affected antioxidant activity, with the highest percentage (89.8%) observed at 150 kg/ha of nitrogen. The highest levels of chlorophyll a, b, and total chlorophyll were achieved with no salicylic acid and 150 kg/ha of nitrogen, showing increases of 140%, 42%, and 116%, respectively, compared to the control (no salicylic acid or nitrogen). The highest total fresh and dry weight was obtained with 100 µM salicylic acid and 100 kg/ha of nitrogen, representing a 75% increase over the control. The highest essential oil percentage (0.87%) and yield (65.6 g/m²) were observed with 10 µM salicylic acid and 150 kg/ha of nitrogen. In contrast, the lowest essential oil yield (18.29 g/m²) and percentage (0.45%) were recorded in the absence of salicylic acid and nitrogen and with no salicylic acid but 150 kg/ha of nitrogen, respectively. Applying nitrogen fertilizer and salicylic acid enhanced the yield and percentage of essential oil, total dry matter, and total phenol content in lemongrass leaves compared to the control. The highest essential oil yield was achieved with 10 µM salicylic acid and 150 kg/ha of nitrogen fertilizer, demonstrating the synergistic effects of these treatments on lemongrass productivity and quality.

In order to study the production potential and competitive power of barley and vetch plants in the mixed cropping pattern under the influence of different planting patterns and the use of nitrogen fertilizer, an experiment was carried out in the 2017-2018 crop year in two research stations of Sisab and Shirvan in North Khorasan province. The type of experimental design was a split plot based on a randomized complete block design, the main factor including nitrogen fertilizer at three levels (0, 50 and 100 kg/ha)and the sub-factor of different cultivation patterns at five levels(barley monoculture, vetch monoculture, Incremental ratios:15, 30, and 45 increased the density of vetch to barley)and the cultivation was mixed and additive. The results showed that the highest amount of barley ash was obtained in the 45:100 mixed crop treatment and in the 100 kg nitrogen fertilizer treatment, while the lowest amount of this trait was in the 100:15 mixed crop treatments and the pure barley crop, which was in the no nitrogen treatment. Was obtained. The highest yield of barley seeds was obtained in the pure cultivation of barley and in the nitrogen treatment of 100 kg/ha (1675 kg/ha), that related to Sisab region and the lowest yield was obtained in the mixed crop of 100:45 and the nitrogen fertilizer treatment (790 kg/ha) that related to Shirvan region. The index of land equality ratio in mixed cropping treatment of 100:45 and nitrogen fertilizer 50 kg had the highest value (LER=1.158) which was obtained in Shirvan region.

To meet the needs of the global population (9.7 billion people) until 2050, a 45 percent increase in corn production is required. Efforts to enhance corn production may be informed, among others, precise N management. This research aims to determine nitrogen dynamics and precise nitrogen nutrient management in corn cultivation using a leaf chlorophyll meter and nitrogen response tests to predict corn yield in tropical upland acid soils. This research was conducted in an Ultisol and verified in an Oxisol. The trial was arranged in a randomized completely block design with eight treatments: 0, 45, 90, 135, 180, 225, 270, and 315 kilograms nitrogen per hectare, repeated three times. The chlorophyll content of corn leaves was measured at 45 and 60 days after planting, using a chlorophyll meter. Data analysis was carried out on vegetative growth and yield, as well as nitrogen content in the soil, leaf, and grains. The study found that the application of nitrogen fertilizer at the rate of 180 kilograms per hectare can alter nitrate concentrations in soil and significantly increases nitrogen uptake, growth, and corn yield. The maximum nitrogen fertilizer rate was 274.5 kilograms nitrogen per hectare, with corresponding chlorophyll meter readings of 52.8 and a corn yield of 8.58 tons per hectare. The corn yield at the rate of maximum nitrogen fertiliser (8.58 tons per hectare) was not significantly different from that at the rate of 180 kilogrammes nitrogen per hectare (8.54 tons per hectare). There was a strong correlation between corn yields and chlorophyll meter values with correlation coefficient of 0.92. The study revealed that applying nitrogen fertilizer at the medium rate of 180 kilograms per hectare can lead to an increase in nitrogen uptake, growth, and corn yield on tropical upland acid soils. There was not a significant difference in corn yield between the rate of nitrogen fertilization at 180 kilograms per hectare and the maximum rate of 274.5 kilograms nitrogen per hectare. In terms of sustainable agriculture management, the medium rate of 180 kilograms nitrogen is recommended for maximizing crop yield on the upland acid soils and minimizing potential environmental impacts associated with excessive use of fertilizers. There is a strong correlation between leaf chlorophyll meter readings and corn yield, suggesting the chlorophyll meter can serve as a reliable tool in the study site in determining optimal fertilizer rates.

The purpose of this research was to determine the optimal amounts of nitrogen fertilizer and irrigation water to achieve maximum yield (Y), water productivity (WP) and fertilizer productivity (FP). For this purpose, the research was carried out on a 370 double cross hybrid corn in the 500-hectare farm of the Seed and Plant Improvement Institute (SPII) for two crop years, using response surface method. The tested factors included the amount of irrigation water at three levels (I1:100, I2:80 and I3:60% of water requirement) and nitrogen fertilizer at three levels (F1:100, F2:60, and F3:0% of fertilizer requirement). The results showed that the model used had an acceptable error for predicting yield (7.3%), water productivity (9.3%), and fertilizer productivity (24%). The accuracy of this model for predicting the desired traits was in the excellent (NRMSE≤0.1), excellent (NRMSE≤0.1), and moderate (0.2≤NRMSE ≤0.3) categories, respectively. The efficiency of the desired model was also favorable (d ≥ 90 and EF≥0.5). By increasing the amount of fertilizer (changing from -1 to +1), the yield also increased, but the rate of yield growth was not linear. The yield changes compared to irrigation water had a more uniform slope and its growth was closer to a linear line. The increase of irrigation water up to the range of +0.8 increased the efficiency of water consumption. Moreover, it reduced the efficiency of water consumption. The changes in the efficiency of fertilizer consumption were positive compared to the two factors of nitrogen fertilizer (up to the range of +0.9) and irrigation water (up to the range of +0.8). The optimal amounts of nitrogen fertilizer and irrigation water were in the range of 60-100% of fertilizer requirement and 70-100% of irrigation water requirement, which after optimization were determined as 71% and 100%, respectively. In these conditions, corn yield, water, and fertilizer productivity were 7 tons/ha, 2.3 kg.m-3, and 33 kg.kg-1, respectively.