نشریه تحقیقات علوم زراعی در مناطق خشک
سال چهارم شماره 1 (پیاپی 7، بهار و تابستان 1401)

Wheat (Triticum aestivum L.) is one of the most important crops and is grown nearly everywhere in the world. Wheat is the primary staple food in many countries. In light of the fact that wheat yield varies depending on environmental conditions, it is crucial to employ strategies that increase wheat yield. To investigate the effects of foliar application of cytokinin on the physiological traits and yield of wheat cultivars, a factorial experiment based on randomized complete block design with tree replications was conducted at the research farm of the Agriculture Faculty, University of Zanjan, during the 2016 cropping seasons. Six wheat cultivars (Azadi, Karaj 3, Roshan, Falat, Sardari and Yavarus) were treated with foliar applications of cytokinin (6-benzylaminopurine) at two levels (0 (control) and 50 µM). At the 50% stage of cluster emergence (code 55 Zadox growth stage), hormone foliar application was performed three times per week. Foliar spraying was done at sunset. To improve absorption, five ml of diluted Tween 20 (0.1%) was added to each 20-liter sprayer. 10 days after the third spraying, a sample was taken and the traits were measured in order to determine their value. The application of cytokinin significantly increased photosynthetic rate, leaf area index durability, weight per thousand grains, biological yield, and grain yield. The application of cytokinin had no significant impact on the greenness index of the Falat, Karaj 3, Roshan, and Yavarus cultivars, but increased the greenness index of the Sardari cultivar by 116.2% and decreased the greenness index of the Falat cultivar by 12.0%. The Karaj 3 cultivar had the highest photosynthesis with an average of 10.6 μmol.m-2.s-1 net CO2 assimilation rate, while the Falat cultivar had the lowest photosynthesis with 6.46 μmol.m-2.s-1 net CO2 assimilation rate. The application of cytokinin increased the leaf area index duration of the Falat, Karaj 3, and Yavarus cultivars while having no effect on the other cultivars. The foliar application of cytokinin had no effect on the number of seeds per plant, but there were significant differences in the number of seeds among the cultivars studied. The cultivars Karaj 3 and Yavarus had the highest and lowest seed yields per plant, with 172.6 and 83.7 seeds per plant, respectively. The foliar application of cytokinin increased the final grain dry weight of the Azadi, Roshan, and Yavarus cultivars by 5.6%, 14.8%, and 6.2%, respectively, but had no effect on the Karaj 3, Falat, and Sardari cultivars. The Azadi cultivar with an average of 1.08 mg/day and the Sardari cultivar with an average of 1.55 mg/day had the lowest and highest grain filling rates, respectively, among the cultivars studied. Except for the cultivar Roshan, the application of cytokinin increased during the grain filling period of all other cultivars. Compared to the control treatment, cytokinin increased the one-thousand seed weight by 5%. Cytokinin increased the weight of one-tousand seeds by 5% compared to the control treatment. The application of cytokinin increased the yield of the Yavarus, Karaj 3, and Sardari cultivars by 23.7%, 30.1%, and 65.5%, respectively, but had no effect on the yield of other cultivars. In the absence of cytokinin application, Azadi had the highest grain yield at 5700 kg/ha, while Roshan had the lowest at 3100 kg/ha. The application of cytokinin had no significant effect on the harvest index. The Sardari and Yavarus cultivars had the highest and lowest harvest indices (31.4% and 25.1%, respectively), whereas the harvest indices of the other cultivars did not differ significantly. Morphological, physiological, and yield-related traits differ among wheat cultivars, as demonstrated by the results of the present study. The results demonstrated that the response of wheat cultivars to cytokinin application was highly variable, and that hormone application may be ineffective or have a negative impact on certain traits.

Cotton (Gossypium hirsutum L.) is one of the oldest agricultural crops, cultivated in over 100 countries with a total production of approximately 25 Mt. This plant's oil, protein, and seed cotton are used in human and animal nutrition, and as the best coating raw material for spinning mills, respectively. Cotton, following sugarcane (Saccharum officinarum) and sugar beet (Beta vulgaris), is Iran's third largest industrial crop and first oil crop. Appropriate agronomic practices, such as plant density and fertilizer management, have a substantial impact on crop development and final yield. Adjusting the distance between cotton rows has been a technique used to increase yield. Typically, cotton is planted in rows separated by 70 to 100 cm. Ultra narrow row (UNR) cotton production has been proposed as a cost-effective method for increasing yields and decreasing production expenses. The fertilizer needs of UNR cotton are not well-established, and the lint yield of UNR cotton relative to that of conventional-row (CR) cotton has been variable. This research aimed to determine the optimal nutrition systems for UNR and CR cotton production. This research was conducted on a private farm in Rudab (Khorasan Razavi province), 60 km from Sabzevar at a latitude of 36° 13',  longitude of 57° 44', and an elevation of 990 m above sea level, during 2019 and 2020. The experimental design consisted of a split plot arrangement of treatments with three replicates in a completely randomized complete block design. The type of fertilizer, which included chemical, organic, chemical+organic, and control (without fertilizer), was regarded as the main plot, while the planting method, which included conventional and ultra-row spacing cultivation, was regarded as the sub plot. Each plot consisted of four 50 cm (UNR) or 25 cm (CR) rows with a length of 4 m and a 20 cm plant spacing. Utilizing a pneumatic seeder and Varamin cultivar, sowing was performed. Before planting, a physicochemical analysis of the experimental soil was conducted. In accordance with the recommendation of the soil test, a uniform dose of phosphorus (150 kg ha-1) in the form of Triple Super Phosphate was applied at the time of sowing as part of the chemical treatment. The recommended amount of N (250 kg ha-1) was applied as urea. One-third of the N was applied at the time of sowing, and the remaining two-thirds were applied in two equal splits at the first and second weedings (50 and 80 days after sowing, respectively). In organic treatment, the rate of poultry manure application was 3000 kg ha-1. In the chemical+organic treatment, each organic and chemical fertilizer was applied at a rate of 50%. At the time of harvest, five plants were randomly selected from the middle rows of each plot and their final height, number of branches, and number of bolls per plant were measured. In order to determine the weight of bolls, 10 bolls were selected at random from the harvested plants and their average weight was determined. The seed cotton yield was harvested at one stage after approximately 90 percent of the bolls had opened. The lint and seeds were separated and weighed separately from the seed cotton. The lint percentage was calculated by dividing the lint weight by the seed cotton weight. The collected data on various parameters were statistically analyzed using SAS (Version 9.4), and the least significant difference (LSD) test at a 5% probability level was used to compare the treatment means. Chemical and organic treatment increased the number of lateral branches (48.7 percent), number of bolls per plant (88.9 percent), and boll weight (131 percent) compared to the control, while organic fertilizer treatment increased lint percentage (42.3 percent). In all nutrition systems, conventional cultivation produced more bolls per plant than ultra-row spacing, and integrated treatment and conventional cultivation produced the greatest number of bolls per plant. In ultra-row spacing and integrated nutrition systems, seed cotton yield was increased by 18.5% over conventional and organic fertilizer and cultivation, and lint yield was increased by 9.28% over conventional cultivation. Overall, the results of this experiment demonstrated that it is possible to produce a satisfactory seed cotton yield by substituting 50 percent of the chemical fertilizers in an integrated system with 50 percent less organic fertilizer and by utilizing ultra-row spacing.

In most developed nations, pumpkin-naked seed (Cucurbita pepo convar. Pepo var. Styriaca) is regarded as one of the most important and valuable plants in the pharmaceutical industry. In traditional and modern medicine, pumpkin-naked seed oil is used to treat a variety of diseases, including prostate hypotrophy, prevention of irregular heart contractions, and treatment of intestinal worms, as well as gastritis, atherosclerosis, decreased blood cholesterol, and decreased risk of bladder and kidney stones. Due to the fact that the environmental conditions for the growth of this plant are rarely optimal and the plants are subjected to a variety of stresses due to the influence of living and nonliving factors, plant yield is diminished relative to plant growth potential. The most significant non-living stress on plant growth and yield is typically drought, especially in arid and semiarid regions of the world such as Iran. About half of the world's agricultural lands are affected by drought stress. Drought stress has caused significant damage to the agricultural sector. Due to the importance of irrigation water in agriculture and the impact of drought stress on crop growth and yield, methods should be implemented to prevent water loss and improve the management of water resources in agriculture, which mitigates the effects of drought stress to some extent. Among these techniques is the use of plastic mulch. The use of plastic mulch in the cultivation of agricultural products for the purpose of increasing soil moisture by reducing the amount of sunlight reaching the soil surface and preventing water evaporation, reducing weeds in the field, and minimizing the damage caused by certain pests. Some crop yields have increased in agriculture throughout the world. This experiment was conducted to determine the effect of different irrigation levels and the use of plastic mulch on pumpkin-naked seed yield and yield components, growth indices, light consumption efficiency, and oil content as the most important quality traits. This study was conducted at the Agricultural Research Station, Ferdowsi University of Mashhad, during 2015-2016 growing season using a split plot design based on randomized complete blocks with three replications. The treatments consisted of three irrigation levels (50, 75, and 100 percent water demand) as the main plot and two mulch surfaces (presence and absence of mulch) as the subplot. At the end of the growing season, yield and its components were evaluated.  The use of plastic mulch for non-stress irrigation (irrigation 100percent water requirement) increased the number of seeds per plant by 5.7% and the relative water content of leaves by 12.8%, but had no significant effect on other traits. However, under mild stress conditions (irrigation of 75% of water requirement), all studied traits except relative growth rate increased, with grain yield (97.3%) having the greatest effect. Also, under conditions of severe stress (irrigation of 50% of water requirement), the use of plastic mulch had the greatest effect on grain yield (312%) but no effect on crop growth rate or relative crop growth rate. In general, the results indicated that maintaining soil moisture and irrigation based on the plant's water requirements can play a significant role in enhancing pumpkin growth and yield. In addition, it was observed that irrigation at 75% of the plant's water requirement and the use of plastic mulch produced the greatest yield, light consumption efficiency, growth indices, and oil content. Therefore, the use of plastic mulch is an effective method for reducing the amount of water a plant consumes in conditions of dehydration.

In this study, the physical and economic productivity of water consumed by five crops (wheat, corn, forage corn, barley, and alfalfa) in Tajan plain located in Mazandaran province were investigated. Population growth, rising demand for agricultural products, unfavorable climatic conditions, dwindling precipitation, and water scarcity are among the world's most pressing problems today. According to studies, the global population will reach 7.8 billion by 2025, putting additional pressure on food security, particularly in developing countries where the population will increase by more than 80 percent. Water's physical and economic efficiency is frequently considered in analysis and decision -making. Physical productivity of water is generally defined as crop yield per cubic meter of water consumed, whereas economic productivity is calculated by dividing the net benefit by the amount of water consumed. Recent water shortages and droughts in Iran necessitate the use of appropriate irrigation techniques for crop cultivation in order to increase crop yields and better manage water resources. In this study, two traditional and modern irrigation systems were compared for the production of five crops (wheat, corn, fodder corn, barley, and alfalfa) in the province of Mazandaran's Tajan plain. In addition, the physical and economic water productivity of five crops were evaluated in order to achieve the optimal state (less water consumption, good crop yield, and high income for farmers).

Tajan catchment has an approximate area of 4005.22 km2, of which 3980.75 km2 are located within Mazandaran province and about 25 km2 are located outside the province. Tajan catchment is located eastern longitude of 53 degrees and 7 minutes to 53 degrees and 42 minutes and a northern latitude of 35 degrees and 56 minutes to 36 degrees and 17 minutes. In this study, data and information from Jihad Agriculture and Regional Water Organization were collected, including soil texture, crop water requirement, cropping area, crop yield, crop water requirement, water inflow to the farm, duration and frequency of irrigation, product prices, and investment costs. A two-stage random sampling method was employed based on the available data and information from Tajan, as well as the various cropping areas and irrigation techniques used in this region. For the study, wheat, corn, forage corn, barley, and alfalfa were chosen as crops. Notably, among the crops, corn is not cultivated using conventional irrigation techniques.

In the traditional irrigation method, the highest yield belonged to forage corn and the lowest yield. Additionally, alfalfa had the highest volume of water consumption while barley had the lowest volume of water consumption. In the traditional irrigation method, forage corn and wheat had the highest and lowest Crop Per Drop (CPD) values, respectively. Also, feed corn and barley had the highest and lowest Net Benefit Per Drop (NBPD) values, respectively. Alfalfa and barley had the highest and lowest Benefit Per Drop (BPD) indices, respectively. Therefore, barley and alfalfa, which have the lowest yield and the highest water consumption using the traditional method, are unsuitable for cultivation in this region. Additionally, in the new method, wheat has the lowest water consumption, but its performance is subpar.

Considering the obtained values of physical and economic water productivity of the aforementioned crops in the Tajan plain, it is advisable not to use traditional methods for irrigating the fields under the aforementioned cropping patterns, with the exception of fodder corn. In addition to barley and wheat, the cultivation of fodder corn, alfalfa, and grain corn is also a top priority. The cultivation of barley using either method of irrigation should be eliminated entirely.

Drought stress is an unavoidable factor that exists in a wide range of environments without boundaries or clear warning, diminishing plant biomass production and quality. It is caused by changes in temperature, light intensity, and precipitation levels. This is despite its cumulative, multidimensional nature, which has a negative impact on plant morphology, physiological, biochemical, and molecular characteristics, as well as the photosynthetic capacity. Plants evolve different adaptation mechanisms to cope with water scarcity, including physiological and biochemical responses, which vary according to species. Plants respond to drought by altering their growth pattern and structural dynamics, reducing transpiration loss through modulation of stomata conductance and distribution, leaf rolling, varying root-to-shoot ratio dynamics, increasing root length, accumulating compatible solutes, and enhancing transpiration efficiency, adjusting hormone levels, and delaying senescence. The purpose of this study was to examine the photosynthetic role of safflower leaves and inflorescence on seed yield and oil content under water stress at Shahid Madani University of Azarbaijan in 2019 using the spring cultivar (Goldasht).

This study examined the effects of different irrigation regimes (no stress, water stress from the beginning of flowering stage, and water stress from 50% of flowering stage) and removing different types of photosynthetic organs (control, removal of leaves from the bottom of the plant, removal of leaves from the top of the plant, and inflorescence cover) on the growth and yield characteristics of safflower. SAS software (version 9.2) was used to perform an analysis of variance (SAS Institute Inc. 2002). At a probability level of 0.05, Duncan's Multiple Range Test was used to separate the means. Using a Class A Evaporation Pan, plots without drought and normal stress were irrigated to a depth of 80 mm from the time of planting until the beginning of flowering. Irrigation was performed at 160 mm evaporation time from water evaporation pans on water-stressed plots.

The highest 1000-seed weight (42.7 g) was associated with the control treatment, whereas the lowest weight (42.1 g) was associated with 50% flowering stress. During stress (seed filling stage), leaf temperatures were 27.9 °C and 26.6 °C, respectively (control). At the beginning of the flowering stage and at the 50% flowering stage, water stress reduced seed yield by 16.4% and 7.9%, respectively. The oil yield decreased significantly by 4.4%, only when the stress treatment was applied from the beginning of flowering. According to the results, the most important source of assimilates for safflower seed filling and oil yield is the top leaves. Also, in this study, the petals play an important role in filling the seeds, both under conditions of full irrigation and water stress. Under full irrigation, the highest harvest index (39.7%) was associated with non-removal of leaves, while the lowest harvest index (38.6%) was associated with removal of top leaves. Without removing the leaves, the highest seed yield (1305 kg/ha) was obtained without water stress. There was no significant difference in chlorophyll index between removing the top leaves of the plant and the inflorescence cover, but more chlorophyll index was obtained by removing the bottom leaves than when organs were not removed. In both treatments, removing the bottom leaves increased the chlorophyll index by 7.4% compared to not removing the leaves.

Studies confirm that removing the leaves at the plant's base increases the chlorophyll index of safflower plants. Additionally, the inflorescence cover plays a significant role in safflower seed and oil yield. Beginning with the flowering stage, safflower seed and oil yields are negatively impacted by water stress.

Quinoa (Chenopodium quinoa) seeds are an excellent source of antioxidants, vitamins (B1, B2, C, E), and minerals (K, Fe, and Zn). Considering its nutritional value, the cultivation of quinoa is crucial. This plant can produce high yields in soils with low fertility. Various natural ecosystems are irreparably harmed by the misuse and imbalanced application of chemical fertilizers. In addition, continuous use of these fertilizers without organic fertilizers will degrade the soil's physical, chemical, and biological properties, leading to environmental degradation. The use of organic fertilizers such as vermicompost increases plant yield and improves soil structure by increasing the amount of available water and nutrients to plants, followed by an increase in the soil's organic matter content. In this study, we proposed optimal levels of vermicompost and chemical fertilizers and evaluated their impact on the elemental content of red quinoa and certain soil properties in the Sistan region.Materials and Methods This research was conducted on the research farm of the University of Zabol during the 2019-2020 growing season. The experiment was conducted using split plots in randomized complete block designs with three replications. In this experiment, three levels of vermicompost were considered for the main plot (zero, five, and ten tons per hectare), while four levels of chemical fertilizer were considered for the subplot (25, 50, 75, and 100 percent). To determine the physical and chemical properties of the soil, samples were taken from a depth range of 0 to 30 cm prior to the commencement of tillage. Before planting, triple superphosphate and potassium sulfate fertilizers were added to the soil. Before planting, during the 6-8 leaf stage, and prior to flowering, nitrogen fertilizer derived from urea is applied. After harvest, the proportion of soil organic matter and grain elements was determined. SAS software (version 9.1) was used for statistical analysis and mean comparison . According to the results, the combined effect of vermicompost and chemical fertilizers was significant for all measured properties with the exception of the concentration of soil -soluble potassium (concentrations of N, P, K, Fe, and Zn in grain, and soil organic matter). Compared to the control treatment, the amount of seed elements such as nitrogen, phosphorus, potassium, zinc, and iron as well as soil organic matter increased by 18.71, 48.71, 16.66, 5.97, 50.64, and 11.82%, respectively, when 10 tons of vermicompost was applied per hectare with 100 percent of the recommended chemical fertilizers. Vermicompost had a significant effect on the concentration of soluble potassium in the soil, but the concentration of this element was unaffected by the combined effects of vermicompost and chemical fertilizers. The highest amount of soil-soluble potassium was produced by 10 tons of vermicompost per hectare, which increased by approximately 29.2% compared to the control treatment. In conjunction with chemical fertilizers, 10 tons of vermicompost per hectare increased soil organic matter and quinoa nutrient concentrations. Development of high-nutritional-value crops that can be grown on low-fertility arable land, such as quinoa, can significantly reduce the use of chemical inputs. Due to the favorable climatic conditions, the introduction of quinoa as a plant that grows in the Sistan region will increase the region's crop diversity, sustainable production, farmer incomes, and food security.

Orzuiyeh city (one of Kerman province's warm regions) is known as the center of wheat production in Kerman province. Wheat is one of the main crops in the region, which plays an important role in providing food for the people and the economy of the region. The high area under wheat cultivation in this city is the most important source of income for farmers. Wheat is primarily sown in Orzuiyeh for bread production using the Chamran cultivar and durum wheat production using the Yavaros cultivar. Due to the introduction of new cultivars, additional cultivars must be introduced to farmers if they outperform conventional cultivars.

The yield of 11 bread wheat (Triticum aestivum) and durum wheat (Triticum turgidum var. Durum) cultivars (Chamran, Shoosh, Parsi, Sivand, Sirvan, Chamran-2, Shabrang, Aflak, Behrang, Baharan, and Mehregan) was evaluated in the hot zone Orzuiyeh in this experiment. The cultivars were compared on yield and performance components over a two-year period using a randomized complete block design with three replications. Each cultivar was planted in six 6-meter lines with a line spacing of 20 cm and the distance between replicates was considered one meter. The amount of fertilizer used was done according to the experiments and according to the needs of the farm soil based on the recommendations of the soil and water department. The first irrigation was done immediately after planting by sprinkling method and according to the custom of the field. Operations and weed control were performed manually (weeding) in the same way on all plots. After physiological maturation of cultivars, harvest was performed in each plot from four middle lines and after removing half a meter from both sides of each line. Grain yield for each treatment was calculated based on the total area of plot harvest and after threshing. Then, based on the obtained data, the analysis of variance of the data was performed in the year. After Bartlett test results, composite analysis of variance was performed by SAS software and mean comparison was performed by LSD method and the results were interpreted.

There was a positive correlation between grain yield, 1000- Grain weight, and Grain per spike. Shabrang, for example, had a higher Grain density per spike and 1000- Grain weight. Additionally, the 1000- Grain weight correlated negatively and statistically significantly with the number of Grains per spike and spike length. At the 1% level, there was also a positive and significant correlation between the number of Grains per spike and the spike length. Additionally, Shabrang cultivar produced the most grain per hectare (8.04 tons), while Chamran cultivar produced the least grain per hectare (6.32 tons). A thousand Behrang cultivar Grains weighed 46 g. Shabrang cultivars typically had 57 se Grains per spike, while Behrang cultivars typically had 39 Grains per spike. Parsi, Shoosh, and Sirvan cultivars, on the other hand, had the longest spikes at 10.7 and 10.4 cm, respectively, while Behrang cultivar had the shortest spikes at an average of 8.1 cm. The Parsi and Aflak cultivars grew to the greatest heights of 101.3 and 99.3 cm, respectively, while the Behrang and Baharan cultivars grew to the smallest heights of 92 and 91.6 cm, respectively.

The Durum Shabrang cultivar should be used in place of the conventional Durum (Yavaros) cultivars, according to the findings of this study. Additionally, Mehregan and Parsi bread wheat cultivars are recommended for use in the Orzuiyeh region in place of Chamran bread wheat cultivars.

Because of the ever-increasing human population and the limited quantity of resources that are currently accessible, it is imperative that these resources be used as effectively as possible. The Sistan region experiences a significant lot of hardship in terms of the availability of water and soil that are suited for agricultural purposes (Wang et al., 2015). The elimination of discrimination between different regions, the guaranteeing of food security, and the lessening of the severity of deprivation among the population of the world are some of the key objectives of sustainable agriculture in the context of environmental protection (Shokati and Feizizadeh, 2019). The cultivation of medicinal plants such as isabgol, which have a low requirement for moisture, a high tolerance to drought, and a high value added, are key solutions for dealing with a multitude of environmental, economic, and social constraints in the Sistan region (Asgharipour and Rafiei, 2010). Using a method known as spatial analysis, the purpose of this study was to determine the agro-ecological zoning of the isbgol plant in the Sistan region in order to identify potential areas for the cultivation of this plant in the Sistan region. This was accomplished in order to fulfill the objective of this research.

In the course of this research, the climatic, topographic, and hydrological layers of the area were analyzed. The appropriate planting areas were zoned using a Geographic Information System (GIS) technique that consisted of Boolean models and Hierarchical Analysis Processing (AHP). In this study, equivalence maps were created with Arc/GIS 10, and then the two-dimensional matrix of each layer was mapped in order of importance using the Idrisi software. Finally, the degree of importance of each component was calculated. At the very end of the process, final maps were produced by combining existing maps in Arc/GIS 10.

According to the findings, only 11 percent of the total arable land area is suitable for the cultivation of isabgol, while 42 percent is suitable, 42 percent is moderately suitable, 31 percent is marginally suitable, and 14 percent is not suitable at all. According to the final map, the areas of the Sistan area that have the greatest potential for isabgol cultivation include the northern parts of the area, as well as parts of the west and southwest, and a small portion of the northeast of the region. Isabgol could be grown successfully in the majority of Zabol's landscapes thanks to the region's favorable growing conditions. However, there are areas of the northwest and a portion of the southwest and northeast, as well as scattered parts of the west and southwest and a portion of the northeast, that are not appropriate for the cultivation of isabgol. Due to the high precision of the Boolean model and the inherent limitations of the AHP model in this respect, the Boolean model also provides better results than the AHP model. Therefore, it is possible to draw the conclusion that the final map that was derived from the Boolean model is very accurate and that it can be used for locating suitable land areas for isabgol in arid and semiarid regions of Iran.

It is possible to apply feasibility assessment models for the aim of management awareness in order to plan appropriately and to maintain environmental sustainability. This can be accomplished through the utilization of management awareness. These models are used to identify medicinal plants that are capable of thriving in each region and are suited for cultivation there. In addition, prospective land-based planning is the best alternative for averting the ongoing crises and lessening the impacts on the environment. This is because prospective land-based planning is focused on looking forward.

Milk thistle contains flavonolignan silymarin in its fruits, making it one of the most important medicinal plants for protecting the liver and treating a variety of liver diseases, such as hepatitis and liver diseases containing toxins. The drought resistance mechanisms of medicinal plants, such as milk thistle, are of critical importance. The investigation of the effect of drought stress on the activity of antioxidant enzymes will aid in the identification of these mechanisms. Water stress modifies plant behavior via its effect on plant metabolism and consequently has a substantial effect on plant production. The biosynthesis pathway of secondary metabolites is altered by environmental stresses, altering the production and concentration of active substances in plants. In addition to playing a crucial role in defense mechanisms, secondary metabolites are an important source of bioactive compounds. However, flavonoids not only have antioxidant activity via the release of free radicals, but they also regulate cellular pathways in the defense of plants against environmental stresses, alter plant metabolism, and have a significant impact on plant production. In order to determine the effect of drought stress on the physiological and biochemical characteristics of milk thistle, treatments of 100%, 75%, 50%, and 25% water requirement were applied in a greenhouse in the village of Shandel, city of Hirmand. There were multiple harvesting stages, including 6 and 13 weeks after planting. Measurements included dry weight, fresh weight, chlorophyll a, chlorophyll b, carotenoids, proteins, proline levels, and antioxidant enzyme activity. First, the data were examined for normality in Minitab software version 18, using the Smearnof Columnograph method to determine data normality, and then the errors were examined for normality to confirm data normality. Then, analysis of variance of all traits and comparison test of Duncan were performed at 5% level with SAS software version 9.2 (SAS 2010).  The analysis of variance revealed significant differences in harvest time, irrigation level, and the interaction between harvest time and irrigation level. In both harvest stages, the concentration of carotenoids began to decrease as the level of stress increased. The amount of chlorophyll a at the stage 6 weeks after planting was less than at the stage 13 weeks after planting, but its amount decreased with increasing stress at both stages. The levels of protein and proline also increased as the level of stress increased. The activity of antioxidant enzymes also increased as the intensity of stress increased, to the point where 100% of water requirements reached the minimum value and 25% reached the maximum value. Due to the fact that most oxidative enzymes in this study increased in response to stress, it can be concluded that catalase, superoxide dismutase, guaiacol peroxidase, polyphenol oxidase, and ascorbate peroxidase can eliminate ROS in this plant. Therefore, milk thistle has a good adaptation to drought stress, which is likely due to the reduction of oxidative damage caused by the activation of the antioxidant system and the accumulation of osmolytes such as proline and protein. These modifications are a form of adaptation to stress conditions. The majority of traits were affected by growth stage and stress level. The levels of protein and proline increased with increasing stress intensity. Most antioxidant enzymes, including catalase, ascorbate peroxidase, and superoxide dismutase, increased in activity under the influence of stress. According to these findings, milk thistle responds to drought stress by increasing proteins and amino acids, decreasing photosynthetic pigments, and increasing the activity of antioxidant enzymes, among other mechanisms. Also, because the amount of metabolites in this plant increases with increasing drought stress, it is possible to determine the stress tolerance threshold of this plant, cultivate it on a large scale, and apply stress to increase secondary metabolites.

Legume crops as human and animal feed are high in protein and have a positive effect on the yield of other crops when grown in rotation with cereals or as cover crops. However, drought can reduce pulse grain yield by 10 to 100 percent. It has been observed that drought stress has different effects on the yield of various genotypes of lentils; additionally, drought stress reduces grain yield in various cultivars of pinto beans and other genotypes of beans. According to reports, nitrogen can effectively mitigate the damaging effects of drought stress on maize. It has also been reported that the application of fertilizer treatments to various chickpea cultivars increases yield. The creation of stress-resistant plant cultivars has always been regarded as an effective method for mitigating the negative effects of stress. Consequently, the purpose of this study was to examine the impact of irrigation stress and varying nitrogen fertilizer levels on yield and yield components of bean genotypes. In 2020, two separate experiments (normal irrigation and low irrigation) were conducted on the research field of the school of Agriculture and Natural Resources at the University of Tehran in order to evaluate the effect of low irrigation stress and different levels of nitrogen fertilizer on bean plant yield and yield components. The experiment was designed with a factorial layout based on a completely randomized block with three replications. The experimental treatments included two levels of irrigation (normal irrigation and 50% normal), five levels of bean genotype (Pak, Dorsa, Goli, Sadri, D81083), and three levels of nitrogen fertilizer (no nitrogen fertilizer, 50% nitrogen fertilizer, and 100% nitrogen fertilizer). SAS 9.4 and Excel 2016 were utilized for data analysis, combined analysis of variance of both experiments, comparison of means, and graphing. Also, Minitab was utilized to examine the homogeneity of error variance. Prior to the combined analysis of variance, the homogeneity of variance of the experiments was examined, and it was determined that the homogeneity of variance of error in none of the experiments (at the one percent level) was rejected. The results of a combined analysis of variance indicated that irrigation stress and bean genotypes had a significant effect on all investigated traits. In addition, the application of different nitrogen fertilizer levels had a significant effect on all traits except harvest index and number of grains per pod. The dual interaction of treatments and the triple interaction of irrigation, nitrogen, and genotype on the number of seeds per pod. A comparison of the means of different levels of irrigation revealed that the values of all yield traits and yield components of beans decreased when low irrigation stress was applied. Significant reduction in grain yield, biological yield, and harvest index percentage under drought stress conditions were 30.5, 23 and 12 percent, respectively, when compared to the fully irrigated treatment, demonstrating the significance of drought stress effects on bean crop yield. The findings of this study indicate that drought stress and nitrogen fertilizer have a significant effect on yield and yield components for all bean genotypes. In such a way that a 30% reduction in grain yield is observed with low irrigation stress. Nevertheless, application of nitrogen fertilizer caused relative resistance of bean genotypes to low irrigation stress, so that using 100% nitrogen fertilizer treatment, the highest grain yield was obtained for white beans (4481 kg / ha), pinto beans Sadri (4373 kg / ha), and red bean (3936 kg / ha), among the five genotypes. In general, the findings of this study indicated that the destructive effects of low irrigation stress or drought on bean grain yield could be mitigated to some extent by selecting suitable bean genotypes and applying appropriate nitrogen fertilizer levels.

Due to the increasing demand for animal protein resources on the one hand and the lack of available water resources on the other, it is crucial to investigate the forage potential of plants for animal nutrition. The Jerusalem artichoke, which is primarily grown for its tubers, produces a substantial amount of forage-worthy aerial parts. However, few studies on the aerial portion of this plant have been conducted in Iran, and those that do exist were conducted at the Research Institute of Animal Sciences in Alborz province. Consequently, the present study was conducted to determine the variations in yield, chemical composition, and digestibility of the Jerusalem artichoke aerial part and its constituents at various growth stages over two consecutive years. To examine the variations in yield and quality of the aerial portion of Jerusalem artichoke, a randomized complete block experiment with 4 replications was conducted in the Agricultural Research Station of Razi University over the course of two consecutive years, 2018 and 2019. From the vegetative stage to full flowering, the yield and yield components (at 7 stages) and chemical composition and digestibility (at 5 stages) of the aerial part of the plant were determined. The chemical composition was determined includes organic matter, ash-free cell wall fibers, water-soluble carbohydrates, and crude protein. In addition, the digestibility of samples whose chemical compositions were measured was determined invitro using two stages of anaerobic digestion and acidic pepsin digestion. In the first and second years, the dry matter yield of Jerusalem artichoke aerial part at two stages of just before flowering and full flowering was 29.1 and 30.4 tons per hectare and 24.0 and 25.3 tons per hectare, respectively. Increased dry matter accumulation in the stem was associated with increased yield during growth stages. These alterations were associated with an increase in height and a decrease in leaf: stem ratio. The ratio of leaf to stem decreased from 1.62 to 0.41 in the first year and from 1.50 to 0.61 in the second year between the vegetative stage and full flowering. In the present study, the increase in aerial organic matter with increasing plant age was due to an increase in stem yield and an increase in its organic matter. During the growth stages, the stem contained more organic matter, insoluble fibers in neutral detergent, and soluble carbohydrates, while the leaf contained more crude protein. Organic matter, insoluble fibers in neutral detergent and acid detergent content, and lignin in the aerial part just before flowering were, respectively, 895.3, 418.7, 310.6, and 85.3 g/kg dry matter over the course of two years of study. With the continuation of the growth period, the water-soluble carbohydrate content increased and the crude protein content decreased to 225 and 92.4 g/kg dry matter, respectively, just prior to flowering. In the aerial portion of the plant, the digestibility of organic matter and dry matter decreased significantly from the vegetative stage to full flowering in the first and second years, respectively, from 64 to 56 and 65 to 59. An increase in cell wall fibers and an increase in the dry matter yield of Jerusalem artichoke aerial part as the plant matured and reached full flowering reduced the digestibility of the forage. However, the yield of digestible organic matter per hectare remained unchanged between the pre-flowering and flowering stages. The highest dry matter yield of Jerusalem artichoke aerial part was obtained at the full flowering stage, but the digestible organic matter yield per hectare remained unchanged from just before flowering to the full flowering stage.

One of the most common environmental stresses that affect plant growth and development is drought stress. This stress directly impacts plant morphology, physiology, and biochemistry of plants. Salicylic acid (SA) is a signaling molecule and hormone-like substance that plays an important role in growth and physiological processes, as well as in the regulation of plant growth and development. The purpose of this research was to determine the effects of SA foliar application on morphological, physiological, and biochemical traits of two mung bean genotypes under drought stress.

This experiment was conducted in 2020 at Shandel village, 13 Km away of Zabol. A split plot design within a randomized complete block design with three replications was used. The main-plots were included irrigation after 70 (as normal conditions), 120, and 180 mm evaporation (as stress conditions) from Class A Evaporation Pan, and the sub-plots include two local cultivars of Sistan and Parto mung bean, and sub-sub-plots included the foliar application of distilled water (control), foliar application of 0.5 and 1 mM SA. Drought stress was applied in the middle of the vegetative growth stage. The foliar application of SA was done in three stages: the vegetative growth stage (20 days after planting), beginning of flowering stage and end of flowering stage. After full plant maturity, plant height, biomass, grain yield and yield components, photosynthetic pigments (chlorophyll and carotenoid), Relative Water Content (RWC), and proline of mung bean were measured.

Analysis of variance of yield traits and yield components revealed significant differences between drought stress levels, cultivar, and application of SA for all traits. The interaction effects of drought stress in cultivar on plant height and grain yield at 1% probability level and on fresh and dry plant weight at 5% probability level were significant and non-significant, respectively, while the interaction effects on other traits were not significant. The interaction effect of stress and SA was significant for the number of pods per plant, thousand seed weight, fresh and dry weight of the plant, grain yield, and the number of pods per m2. The interaction effect between SA and cultivar were not significant on 1000-seed weight, fresh and dry weight of the plant. The interaction of stress × cultivars, and SA was significant on all traits except grain yield and the number of pods per square meter.Drought stress has a profound effect on photosynthesis and water potentials of plant. Grain Yield and yield components were better in Parto cultivar than local Sistan cultivar. It is possible that the presence of superior stress resistance genes in Parto cultivars has caused higher yield and yield components than the local cultivar. Application of SA increased pod production per plant. Foliar application of SA probably reduces flower loss by reducing the adverse effects of stress and increases the number of pods per plant and consequently the number of pods per square meter. Foliar application of SA increases photosynthesis by improving photosynthetic pigments. In addition, foliar application of SA enhances photosynthesis, resulting in an increase in 1000-seed weight. SA, as an important signaling molecule, promotes plant growth and induced abiotic stress tolerance. Likely SA increases growth and yield by increasing potassium, phosphorus, nitrogen, and calcium concentrations. The effect of this hormone on other plant hormones that increase vegetative growth and increase cell division in meristematic regions, and cell growth may also contribute to the growth enhancement.

Based on the present study findings, drought stress had a negative effect on all traits examined. The effect of SA at a concentration of 1 mM was the highest in non-stress conditions and in the Parto cultivar. The Parto cultivar was better compared to another cultivar. Foliar application of SA improved drought resistance in both cultivars. This improvement was greater in Parto cultivar than local Sistan cultivar. Based on the results of this experiment, it is recommended to improve the yield and growth characteristics of mung bean during stress conditions. It also seems that Parto cultivar performs better in Sistan's conditions than the local cultivar of Sistan.

Barijeh is a monocarpic perennial plant belonging to the Umbellifers family. It is one of the most valuable native plants of Iran, and its extracts is a significant export item of Iram. The propagation of plants is one of the most essential processes for the plant sustaining life. In situations where plant propagation via seeds is impossible or problematic, asexual propagation techniques, such as transplantation, can be used. Due to the preservation of genetic characteristics and the absence of somaclone diversity in plants, transplanting is an appropriate technique for large-scale plant production. Increasing the growth rate of young seedlings can frequently shorten the seedling period and advance the plant to the fruiting stage. Type of transplant and age at the time of transplant appear to be influential in this regard. This experiment was conducted in the greenhouse and research farm of the Shirvan Branch of Islamic Azad University in 2018-2019 using a randomized complete block design with three replications and two factors in a factorial arrangement. The first factor was the type of grafting performed on the Barijeh, which was examined at four levels: control (no grafting), tuber grafting, leaf grafting, and crown grafting. The second factor was the age of the grafts, which was examined at four levels: annual, biennial, triple, and four-year-old grafts. Mid-May 2018 saw the preparation of basic plants (aged five years) and tested scions from the botanical garden of the North Khorasan Research Center in Bojnourd. End of May of the same year, three types of transplantation were performed on basic plants: tuber, stem, and leaf transplantation. Midwinter saw the transfer of seedlings to the main land, where they began vegetative growth in early March. At the end of May 2019, three months after the transfer of seedlings to the main land, graft yield, stem height, leaf number, leaf inclination, and tuber length were measured. In addition, once the plant entered its reproductive phase (early July), the number of flowers per plant was measured on June 1 and the number of seeds per plant was measured in late June. Data analysis were performed by Mini tab statistical software version 17 and comparison of means were performed using LSD test at a 1% probability level. The results indicated that the interaction effect of graft type and age was significant for all investigated traits. Tubular and four-year-old grafts had the highest graft success, leaf length, and stem height, at 80%, 3.56 cm, and 4.47 cm, respectively. The greatest number of leaves was observed on four-year-old grafts in the control and tuber graft treatments, and only in these two treatments the number of leaves reached more than 11 leaves per plant. The longest tuber length was observed in three-year-old and four-year-old control and tuber graft treatments, and only in these four treatments the tuber length was observed at more than 24 cm. The success of the grafting is contingent on a number of factors, including the type of base, the physiological condition of the base, the type of graft, the origin of the graft, the age and duration of the graft, and the compatibility of the base and the graft. Because the crown diameters of one- to four-year-old plants used as grafts on five-year-old mature plants as grafting bases were smaller in the present study and in the study of barijeh, crown grafting was less successful. Due to insufficient contact between the rootstock and the graft, leaf grafting was not particularly successful. This experiment revealed that the optimal transplantation method for barijeh is tuber grafting, while the optimal age for graft selection is a four-year-old plant.

Tobacco, scientifically known as Nicotiana tabacum L. is an annual allotetraploid plant (2n=4x=48) in the Solanaceae family and is widely used as a model in plant biology. Oriental tobacco is a sun-cured, highly aromatic, small-leafed type which is mainly grown in Turkey, Iran, Greece, Bulgaria, Lebanon and the Republic of Macedonia. It is capable of growing in low fertile soils. To create an American Blend cigarette, it is necessary to mixed oriental tobacco with more robust tobacco such as Virginia and Burley tobaccos. Estimating genetic diversity and knowledge on genetic relationships among genotypes is a crucial aspect of promoting and implementing breeding programs; without it, effective and desirable genetic modification cannot be accomplished. Various types of marker including morphological, biochemical, and molecular ones are used by plant breeders to estimate genetic diversity. The purpose of this study is to investigate the genetic diversity in the population of recombinant inbred lines for chemical characteristics such as chlorine accumulation in leaves, nicotine, sugar and ash. In the present study, genetic diversity of an oriental tobacco population consists of 55 recombinant inbred lines; coming from Basma seres 31 × SPT 406 cross, was assessed for chemical traits in randomized complete block design with three replications. From the middle leaves of each genotype, 20 leaves were randomly selected in each replication and the percentage of chemical elements such as chlorine, sugar content, nicotine contentand ash content was determined using the method proposed by CORESTA (Cooperation Center for Scientific Research Relative to Tobacco). The identification of outlier data and the test of normality of the distribution of experimental errors were performed according to Shapiro and Wilke's method in SAS software version 4.9. Analysis of variance of the chemical traits data was performed according to the statistical model of randomized complete block design in the SAS software. After standardizing the data, the cluster analysis was carried out using the minimum variance method. Principal components analysis was performed using the correlation coefficients matrix of traits. The average comparisons of the groups resulting from the cluster analysis was done in SPSS version 20 software using the SNK method. Analysis of variance revealed significant difference among the studied lines for nicotine and chlorine concentration. There was significant negative correlation between nicotine and sugar and significant positive correlation was observed between sugar and ash. Principal component analysis revealed 3 of the 4 main components play the most important role in explaining the total diversity among individuals and all traits except chlorine concentration showed negative correlation with the first component. Using cluster analysis by Ward’s method, the studied population was grouped into 4 separate subgroups. Groups mean comparisons using SNK test showed that individuals in group 1 have the higher values for most of the studied traits. According to the present study, a wide genetic diversity was observed for nicotine and chlorine traits in the studied population, which can be used in breeding programs for oriental tobacco. A negative correlation was observed between nicotine and sugar, and a positive correlation between sugar and ash. This can be used to modify correlated attributes, as increasing or decreasing the value of a trait increase or decrease the traits associated with that trait. Individuals of the studied population were divided into 4 separate groups, which can help researchers in choosing parents because offspring resulting from the crossing of distant parents; show more heterosis and diversity. Production of desirable varieties increases the farmers' incomes by reducing the average production costs.

Barley (Hordeum vulgare) is the fourth most important crop in the world. It is commonly used for human food, malt, and animal feed. Through the study of pedigrees, morphological and biological traits, and molecular markers, it is possible to estimate the genetic diversity of crops, which plays an essential role in promoting breeding programs and preserving genetic resources. This study aims to identify superior barley genotypes in terms of phenological and morphological traits, group them using cluster analysis, and reduce the measured traits using principal component analysis. To evaluate the genetic diversity of spring barley genotypes based on phenological and morphological traits, an experiment was conducted at Divandareh Dryland Agricultural Research Station using a randomized complete block design with 27 genotypes in four replications. In this investigation, plant height, tillering date, shooting date, flag leaf width, flag leaf length, awn length, spike length, internode length, diameter at node location, internode diameter, flowering date, dough stage, milk stage, rootlet weight, grain yield per plant, biomass per plant, total biomass, 1000 grains weight, harvest index, number of fertile stems, number of florets per spike, number of grains per spike, number of leaves at spike emergence, germination date, maturity date, number of grains per plant, spike emergence date and total grain yield were evaluated. Analysis of variance was performed, and the method of least significant differences was used to compare the means (LSD). Using Pearson's correlation coefficient, the relationship between the studied traits was determined. Principal component analysis was utilized for data reduction. Using cluster analysis, the studied genotypes were grouped. MSTATC and SPSS softwares were utilized for data analysis. Except for flowering date, differences between genotypes were significant for the majority of traits, indicating a high level of diversity among spring barley genotypes. Greater heritability was observed for total grain yield, number of fertile shoots, main spike length, harvest index, and flag leaf length than for other traits. These traits can be used to segregate generations for indirect grain yield selection due to their high heritability. Path analysis (by stepwise regression) revealed that number of grains per plant and 1000-grain weight had a direct and significant effect on total grain yield, whereas the direct effect of awn weight on grain yield was less than that of number of grains per plant and 1000-grain weight. Therefore, grain number per plant and 1000-grain weight were the most influential factors in spring barley grain yield. Based on the evaluated traits, the cluster analysis divided the studied genotypes into three groups. The genotype 1 was found in the first cluster, the genotypes 26, 25, 27, 22, 14, 13, and the remaining genotypes were found in the third cluster. The first three principal components in principal component analysis explained 52.88 % of the total variance. The respective values for the second and third components were 17.23% and 9.15%. The traits of booting date (0.884), number of grains per spike (0.855), flowering date (0.776), and flag leaf width (0.883) had positive coefficients and high values in the first component. In the second component, plant height (0.885), shooting date (0.880), and flag leaf length (0.873) all had large positive coefficients, whereas 1000 -grain weight (-0.387) and plant weight (-0.377) had large negative coefficients. The number of leaves can be proposed as the third component. Cluster emergence date (0.586), milk stage (0.739), and number of grains per plant (0.570) had high coefficients in the third component. The third component is maturity-related characteristics. According to the means, the third cluster of genotypes can be utilized in grain yield breeding programs. Based on the results, the first component shall be designated as the grain yield and total biomass component. This component can be used for spring barley genotype selection.

Carbon sequestration in biomass and soils is one of the simplest and least expensive ecological strategies for removing carbon dioxide (Uri, 2000). According to researchers, carbon sequestration is an important factor in reducing global warming (Wiesmeier et al., 2014). It was demonstrated that returning fifty percent of plant residues increased the soil's capacity to sequester carbon (Yan et al., 2007). Another study revealed that the wheat-rice cultivation system sequestered 55% more carbon in fields with animal manure and 70% more carbon in fields with chemical fertilizer than the wheat-corn system (Kukal and Benbi, 2009). Given the low levels of soil organic matter in Iran's arid and semi-arid regions, particularly in the agricultural ecosystems of North Khorasan, it is crucial to employ strategies that increase the carbon content of soil organic matter. Therefore, the purpose of this study was to assess the carbon sequestration capacity of the aerial and subterranean portions of wheat and the global warming potential of the wheat production ecosystems in the province of North Khorasan.

In order to assess the carbon sequestration and global warming potentials of irrigated and rainfed wheat cultivars, an experiment was conducted in Shirvan, North Khorasan province, during the 2020-2021 growing season. For this purpose, systematic random sampling was conducted in 30 farms with 0-30 cm of soil depth, and a face-to-face questionnaire was used to assess greenhouse gas emissions and global warming potential. The studied irrigated varieties included Mihan, Pishgam, and Heydari, while the studied rainfed varieties include Azar 2 and Baran.  In order to carry out the research, systematic random sampling (Chambers, 1983) was done from six points in 30 farms from a soil depth of 0-30 cm (Mahdavi et al., 2009). In the spring, vegetative and reproductive organs such as seed + spike, stem, leaf, and root were harvested at three distinct phenological stages (shooting, flowering and physiological ripening). To study the soil, six 30-cm-deep profiles were dug under each plant and soil samples were collected. The combustion method (Abdi et al., 2008; Foroozeh and Mirzaali, 2006) was utilized to determine the organ conversion coefficients.

The results indicated that irrigated cultivars had a higher shoot conversion efficiency than rainfed cultivars, with the Pishgam cultivar having the highest average conversion efficiency at 49.68%. Among the irrigated cultivars studied, the Mihan cultivar had the highest total carbon sequestration capacity, averaging 3,398.70 kg/ha. Among rainfed cultivars, the Baran cultivar had a higher total carbon sequestration than the Azar 2 cultivar, which had an average of 512.60 kg/ha. The amount of greenhouse gases (CO2, N2O, and CH4) produced in irrigated and rainfed wheat fields in Shirvan was estimated to be 1626.932 kg/ha and 651.33 kg/ha, respectively, and the global warming potential of one hectare of wheat was equal to 3404.890 kg of carbon dioxide and one hectare of rainfed wheat was equal to 919.263 kg of carbon dioxide. The cultivation of Mihan (irrigated) and Baran (rainfed) cultivars in the agroecosystem of North Khorasan will increase carbon sequestration capacity and decrease CO2 emissions, according to the findings of this study.

Based on the results of this study, the aerial carbon sequestration capacity of irrigated wheat cultivars was greater than that of rainfed cultivars. Moreover, among plant organs, the wheat leaves had a greater capacity for carbon sequestration than the wheat roots. Mihan was the cultivar with the highest aerial carbon sequestration capacity among irrigated cultivars, while Baran was the cultivar with the highest aerial carbon sequestration capacity among rainfed cultivars.

Echinacea (Echinacea purpurea L.) is a herbaceous, perennial plant in the sunflower family; its essential oil and extract are widely used in the pharmaceutical, food, health, and cosmetic industries; and it has antimicrobial, anti-oxidant, and radical -neutralizing properties. Anti-allergy, anti-tumor, and anti-inflammatory properties have been ascribed to them. In arid and semiarid regions, a lack of water and inefficient irrigation techniques are the primary factors limiting the development of the agricultural sector. Drought is one of the most influential stresses on crop performance, and it is well known that it affects a number of physiological processes in plants. This investigation sought to determine the impact of biochar and salicylic acid on the physiological traits and yield of echinacea (Echinacea purpurea L.) under non-stress and drought -stress conditions.  In order to examine the effect of biochar (in three levels without biochar as control, 20 t×ha-1 and 40 t×ha-1) and salicylic acid (in three levels of zero, 0.5 mM and 1 mM) in two humid environments (no stress and drought stress), a factorial experiment in split plot experiment was carried out in Ilam province (two locations) in a randomized complete block design with three replicates in 2020. The evaluated traits included chlorophyll a, chlorophyll b, carotenoids, soluble carbohydrates, total protein, proline activity, and biological yield. The results indicate that the highest increase in biological yield was 45.97% and 45.42%, respectively, in the treatment combination of 40 tons of biochar and no salicylic acid foliar spray and the treatment combination of 20 t ha-1 of biochar and 0.5% salicylic acid foliar spray in the condition of 75% drought stress.  Proline content decreased in all treatment compounds; except in the combination of non-drought stress treatment and use of 40 t ha-1 of biochar and 0.5% salicylic acid which increased by 25.71%. The highest increase in carotenoids (36.66%) was obtained if 40 t ha-1 of biochar were used and salicylic acid was not sprayed under 50% drought stress. Also, the results show that by using 20 t ha-1 of biochar and spraying 1% salicylic acid under 50% drought stress, the amount of carotenoids increased by 33.33% compared to the control. As one of the growth regulators, salicylic acid was used to increase plant tolerance to stresses such as drought. In addition, biochar had a positive impact on the enhancement of several physiological characteristics and echinacea yield. Echinacea purpurea L. appears to benefit from the use of biochar and salicylic acid to mitigate the negative effects of drought stress.

The cultivation of quinoa (Chenopodium quinoa Willd), an annual plant with high nutritional and economic significance, is expanding throughout the world. Quinoa is a traditional Andean seed crop highly tolerant to abiotic stresses. Since most seed crop cultivars are sensitive to drought stress, quinoa is regarded as a valuable candidate for the plant's exposure to harsh environmental conditions. Due to the importance of quinoa in arid regions, the effects of seed priming on yield and certain morphological and physiological traits were investigated in this study.

A factorial split-plot experiment based on a randomized complete block was designed with four replications was conducted in 2019 at Damghan Research Farm Station. The experimental treatments included drought stress based on the plant's water requirement at three levels (100% (control), 75%, and 50%) as the main factor, and sub-factors included three cultivars (Titicaca, Q26, and Q29) as well as priming at two levels (no priming and hydropriming) as a factorial experiment into sub-levels. To perform water requirement (WR) treatment, WR were calculated using the CROPWAT program and then applied to the 6-leaf stage plants.

The results demonstrated that drought stress (50% WR) reduced  relative leaf water content (13.1%), leaf membrane stability index (21.2%), chlorophyll content (38.7%), 1000-seed weight (18.2%), number of panicles per plant (27.5%), number of seeds per panicle (7.71%), and seed yield (40.4%). The use of hydropriming increased the membrane stability index, leaf chlorophyll content, 1000-seed weight, and the number of panicles per plant. Under 50% WR, the activity of antioxidant enzymes such as catalase and leaf ascorbate peroxidase increased by 139.58 and 42.55 percent, respectively, compared to the control. Additionally, drought stress increased quinoa seed protein content and decreased seed yield.. The percentage of seed yield reduction in drought stress was 50% and 75% of WR and was lower in Titicaca than the other two cultivars.  The comparison of the mean of irrigation interactions in the cultivars revealed that 100% WR produced the maximum quantities of Chl a, Chl b, and carotenoids in all three cultivars. Additionally, seed priming boosted the Chl a, and Chl b concentrations in Titicaca and Q26. Furthermore, the highest biological yield in the Damghan region was achieved in Q26 with 100% WR. Under normal irrigation conditions, Q26 cultivar had the highest seed yield, whereas under drought stress conditions, the seed yield of all cultivars decreased significantly. Nevertheless, this decline in the Titicaca cultivar was 12% less than in Q26 and Q29. The findings of the mean comparison revealed that priming improved seed yield in all three cultivars, with the Q29 cultivar producing the maximum seed yield at 1,452.03 kg/ha.

In general, Titicaca cultivar was more resistant to drought stress than other cultivars, hence its cultivation is encouraged in the Damghan region. Within the scope of this study, the use of hydropriming to improve quinoa's physiological features in conditions of drought stress is suggested. In conclusion, the results demonstrated that seed priming significantly increased seed yield, biological yield, leaf area index, and chlorophyll content in drought-stressed quinoa cultivars. These results indicated that seed priming can play a significant role in enhancing quinoa's drought resistance under low irrigation conditions. This study could contribute to the understanding of seed priming effects, which could be applied as an effective strategy to mitigate the negative effects of drought stress on quinoa cultivars.

It is crucial  to introduce and develop new high-yielding dryland wheat cultivars with resistance to biotic and abiotic stresses, given the extent of wheat cultivation in tropical regions and the occurrence of drought in recent years. On-farm experimentation provides new insights and is a suitable method for informing farmers about novel technologies, such as new crop varieties. Using the SIIG index and cluster analysis, the current study aimed to identify the superior wheat genotypes for grain yield and other agronomic traits in tropical drylands and introduce them to farmers. In current study, 33 varieties/ pure lines selected from the DARI and ICARDA wheat breeding programs were cultivated on farmers' fields of Lorestan province using a randomized complete block design (RCBD) with two replications during 2017-18 cropping season. The genotypes evaluated consisted of 12 cultivars and 21 pure lines of bread wheat and durum wheat, respectively. The pedigree of all genotypes is presented in table 1. The following nine characteristics were recorded: days to heading (DH), plant height (PH), Days to maturity (DM), spikes per square meter (SSM), number of grains per spike (NGPS), 1000 kernel weight (TKW), biological yield (BY), Grain yield (GY), and harvest index (HI). Using ANOVA, all investigated characteristics were analyzed. Genotypes means were compared using the least significance difference (LSD) at 5% and 1% probability level. Correlation analysis was performed using the Pearson method. Selection index of ideal genotype (SIIG) was utilized to select the genotypes with the highest yield and agronomic traits. In addition, cluster analysis using the WARD method and principal component analysis were employed to categorize genotypes. To analyze the data, MSTATC, IBM SPSS Statistics ver. 22 and Excel were utilized.  Paya and Kabir varieties and G17, G18, and G31 lines had the highest average grain yields, with yields of 5,280, 3,985, 4,210, 4,003, and 3,950 kg/ha, respectively. The SIIG index indicated that Kabir and Paya varieties, and G31, G18, G29, G17 and G16 lines with a high SIIG value (0.822, 0.720, 0.791, 0.779, 0.767, 0.736 and 0.745, respectively) were superior genotypes, whereas G13 and G17 lines with a low SIIG (0.582 and 0.576, respectively) were the weakest genotypes for the majority of traits evaluated in the current study. Grain yield exhibited a significant and positive correlation with biological yield (BY), number of grains per spike (NGPS), and harvest index, according to correlation analysis (HI). Days to heading and maturity correlated negatively with grain yield. Therefore, BY, NGPS, HI, and early maturity may be suitable indicators for selecting high-performing genotypes in wheat breeding programs under rainfed conditions. Strong and positive correlation was observed between the SIIG index and grain yield. This issue reflected a larger proportion of grain yield in the SIIG index. Cluster analysis classified genotypes into three primary classes. Class 1 consisted of maturity date genotypes with high yield, Class 2 consisted of early maturity genotypes with low yield, and Class 3 consisted of early maturity genotypes with low yield. In the current study, first -class genotypes with high yield and earliness were deemed promising genotypes for planting in tropical regions under rainfed conditions or as parents for improving yield and desirable agronomic traits in wheat breeding programs. The best genotypes, as determined by the SIIG index and cluster analysis, are the Kabir and Paya varieties and the G31, G18, G29, G17, and G16 lines, which are suitable for planting in drylands and further breeding programs. Significant and positive correlations between grain yield and biological yield (BY), number of grains per spike (NGPS), and harvest index (HI) indicated that these traits could be regarded as suitable indicators for enhancing grain yield in wheat under rainfed conditions. In the current study, genotypes with higher grain yield and desirable agronomic traits had the highest SIIG index. SIIG index could therefore be utilized as a suitable method for identifying the best genotypes on various crops.

Water is essential for the production of biomass and grain by plants. In recent years, deficit irrigation induced by partial root zone irrigation has been one of the methods used to increase water productivity in agronomic systems. In this method, only a portion of the root system is irrigated and is exposed to semi- moistened and semi dried conditions. In sustainable agriculture , on the other hand, efforts are made to reduce the use of chemical fertilizers due to their negative impact on agronomic systems, such as reducing water and plant root penetration into soil and causing soil degradation. However, plants should be supplied with nutrients through other means, such as manure and compost. In order to reduce water consumption in agricultural systems, low-intensity irrigation has always been regarded as an essential management strategy. Due to the fact that, in the majority of the country, a decrease in precipitation occurs during the reproductive growth period of crops, resulting in a limitation of grain filling, research on limited irrigation techniques that can optimally reduce water consumption in agricultural systems is a top priority.

The research was carried out in Shadegan, Khuzestan during 2018-19. A two-factor factorial experiment based on randomized complete block design and three replications were employed to compare the treatments. The first factor was the irrigation regime applied after seedling establishment. The twoirrigation treatments were total root zone irrigation (I1) and partial root zone irrigation (I2). In complete irrigation, furrows were completely irrigated. In the partial root zone irrigation method, alternate furrow irrigation was used. The control (no fertilizer), chemical fertilizer, animal manure (cow manure), and compost comprised the second factor. Urea (100 kg ha-1), triple super phosphate (100 kg ha-1) and potassium sulfate (100 kg ha-1) were used as chemical fertilizers (50 kg ha-1). Before planting, the entire amount of compost (30 t ha-1) and cow manure (30 t ha-1) was applied. Each plot's incoming water volume was measured.

The interaction between irrigation and fertilizer had a significant effect on grain number per plant, biological yield, and water productivity (P≤0.01) and grain yield (P≤0.05). With the application of chemical fertilizer and thorough irrigation, the highest grain yield (3051 kg ha-1) was achieved. Grain yield of faba bean under partial root zone irrigation and chemical fertilizer was 9.2% more than that of complete irrigation and control (no fertilizer) treatment. The application of fertilizer increased the grain yield of faba bean under partial root zone irrigation (in chemical fertilizer, animal manure and compost was 42%, 40% and 31% more than that of control (no fertilizer), respectively). However, only when chemical fertilizer was used was the grain yield of faba bean greater under partial root zone irrigation than under full irrigation and no fertilization. Other fertilizer treatments were unable to compensate for deficit irrigation's negative effects on faba bean grain yield. The highest (1.73) and lowest (0.83) of water productivity (kg grain m-3) were achieved with the application of chemical fertilizer under partial root zone irrigation and no fertilizer application under full irrigation regime, respectively. Compost did not improved water productivity under full irrigation. However, under partial root zone irrigation, compost resulted in higher water productivity compared with all fertilizer treatments under full irrigation. The highest water productivity under partial root zone irrigation (1.73) was more than 40% more than the highest water productivity under full irrigation (1.037).

The results of the present research confirm that partial root zone irrigation can help improve water productivity by reducing water consumption while maintaining grain yield. Furthermore, animal manure and compost cannot be used as a replacement of chemical fertilizers because slow release of nutrients.