جستجوی مقالات مرتبط با کلیدواژه « Water requirement » در نشریات گروه « زراعت »

Environmental disorders that significantly disturb the growth and yield of plants are considered as stress conditions and cause disturbances in biological. Drought stress is one of these environmental conditions which has been increased as a result of climate change and has been a negative effect on the yield of crops in the world. Every year about 12 million hectares of productive land has become dry and barren due to human activities and climate. More than 6000 varieties of quinoa are cultivated by farmers in the worlds. Quinoa is a plant responds to drought stress through escape, tolerance and avoidance of drought and has an extraordinary capacity for cultivation in dry and low-water soils because of its capabilities such as low inherent need for water, the maintenance of leaf surface and the ability to resume the speed of photosynthesis after drought stress. Titicaca, Redcarina and Giza-1 are three quinoa cultivars. Titicaca and Redcarina, were registered on December 14, 2009 and January 31, 2005, respectively, and are native to Denmark and Netherlands, respectively, and Giza1 is native to Egypt. Increasing yield in water deficit conditions requires the identification of genotypes resistant to drought stress. Different quantitative indicators have been provided to evaluate the reaction of genotypes in environmental conditions and also to determine their tolerance and sensitivity.

In order to evaluate the indicators of drought stress tolerance of quinoa cultivars, a factorial experiment with four stress levels (100, 75, 50 and 25% of water requirement) and three varieties of quinoa (Titicaca, Giza-1 and Redcarina) were conducted with three replications in two locations (Birjand and Sarbisheh region) and two planting dates, spring (March) and summer (July) in 2018 and 2019. Evaluation of cultivars in terms of drought tolerance was done using stress sensitivity indices, such as tolerance (TOL), mean productivity (MP), stress tolerance index (STI), geometric mean productivity (GMP) and harmonic mean (HM). Decomposition into main components on yield under stress and non-stress conditions and drought stress tolerance indices were displayed in the form of a biplot diagram using STATISTICA software.

The results showed that in both regions the highest amount of STI, MP, GMP and HM indices, were recorded for Redcarina variety in all three levels of drought stress at spring cultivation, but they were belonged to Giza-1 at summer cultivation. Due to the dispersion of the results, SSI and TOL indices had less diagnostic power to evaluate the drought tolerance of quinoa cultivars. Principal components analysis showed that Redcarina cultivar was collinear with yield vector in stress condition and MP, GMP, STI and HM indicators and was located in yield potential and tension tolerant area in bi-plot diagram in two regions (Birjand and Sarbisheh) at spring cultivation. In summer cultivation, Giza-1 variety was located at sensitive to stress area and yield potential in bi-plot diagram and was collinear with grain yield vectors in non-stress conditions and MP, GMP, STI and HM indices in two regions. This showed the more yield of this variety in non-stress condition. In most of the planting dates and places were studied, Titicaca cultivar had collinearity with SSI vector or located at the closest position to this vector, which indicated that this cultivar was sensitive to stress.

In general, in July, Giza-1 variety and in March Redcarina variety were the most tolerance varieties and Titicaca was most sensitive cultivar to drought stress.
Keywords

In order to investigate the effect of different methods and levels of irrigation water on some vegetative and reproductive characteristics of saffron, this research was carried out in the form of a split-plot experiment in the form of a randomized complete block design with three replications at the Razavi Khorasan Agricultural and Natural Resources Research and Training Center. (Gonabad Research Station) was carried out in the crop years of 2017-2018. In this research, irrigation method treatments (including basin, drip and sprinkler (Pflex) methods) were in the main plot and different levels of irrigation water (including supplying 100, 75 and 50% of the water requirement) were in the sub plot. Results The comparison of the averages showed that in both years of the experiment, changing the irrigation method from basin to drip (tape) and sprinkler (P-flex) led to an increase in the studied properties. Reducing the amount of irrigation water from 100% to 50% of the water requirement also caused a decrease in leaf characteristics and stigma yield, but the efficiency of irrigation water consumption increased. Based on this, reducing the water requirement of saffron from 100 to 50% in the first and second year caused a 33% and 30% decrease in stigma yield, and a 32% and 37% increase in water consumption efficiency, respectively. Examining the interaction effects table showed that in the first year of the experiment, reducing the amount of irrigation from 100 to 50% caused a greater reduction in the total length of leaves per square meter under drip irrigation (tape) than the other two irrigation methods (82% in the drip method (tape) in contrast to 79% in the sprinkler (P-flex) method and 69% in the basin method). Based on this, although the positive effect and relative advantage of modern irrigation systems is decreasing with the increase in the age of the farm, it seems that it is possible to achieve optimal performance in the region by using rain irrigation sprinkler (P-flex) method in 100% of the water requirement.

In order to investigate the effect of irrigation regimes and amounts of humic acid on the quantitative and qualitative characteristics of peanuts, an experiment was conducted a split in a randomized complete block design. It was performed with three replications in the cropping years of 2018 and 2019 in Astana-Ashrafieh city of Guilan province. Experimental treatments included irrigation regime (rainfed and water requirement of 60, 80 and 100%) as the first factor and humic acid (without fertilizer, 3, 6 and 9 L.ha-1) as the second (secondary) factor. The results showed that the interaction of irrigation and humic acid on biological yield and pod and grain yield was significant. The highest grain yield was obtained in the irrigation treatment of 100 and 80% of water requirement and with the use of humic acid 9 L.ha-1 with an average of 2562 and 2526 kg.ha-1, respectively. Biological yield under 80 and 100% water requirement was 6714 and 6772 kg.ha-1, respectively. The highest biological yield was observed in different amounts of humic acid in treatments of 9 L.ha-1 at the amount of 7436 kg.ha-1. Pod yield in the treatment of 80 and 100% of water requirement were 2427 and 2435 kg.ha-1, respectively. The lowest and highest pod yields in different amounts of humic acid were in the treatments without fertilizer and 9 L.ha-1 with an average of 1453 and 2706 kg.ha-1, respectively. Treatment of 80% of plant water requirement and the amount of humic acid consumed at 9 L.ha-1 with an average of 745.5 kg.ha-1, had the highest rate compared to other treatments. According to the research results, the use of humic acid 9 L.ha-1 can be suggested by providing 80% of water requirement as suitable conditions for the study area.

Water and nitrogen are known as the two main limiting factors in achieving maximum yield in agriculture. Therefore, the use of nitrogen fertilizer plays a significant role in increasing agricultural production. However, the indiscriminate use of these fertilizers may be due to their low efficiency. Therefore, investigating the challenges of water scarcity and improper nitrogen use management is crucial. In this study, considering the challenges of water scarcity and improper nitrogen use management, an investigation has been conducted.

This experiment was conducted in the research farm of the Agriculture Faculty of Shirvan Azad University during the agricultural year of 1399-1400. The experiment was carried out in the form of strip plots in three replicates and in a complete randomized block design. Three levels of 50%, 75%, and 100% of plant water requirement were considered as the main plot and five levels of zero (N0), 100 (N100), 200 (N200), 300 (N300), and 400 (N400) kilograms of nitrogen per hectare were considered in the subplots.

Most attributes related to yield components had higher values during the second year in comparison with the first year of the experiment. Moreover, plant height, grain weight, rows per cob and kernels per row in the 100% water requirement were greater compared with the 50% water requirement treatment. As a result of 400 kg/ha nitrogen fertilizer application, plant height, rows per cob, kernels per row, 100-grain weight and biological yield increased by 24.4%, 24.6%, 23.8%, 24% and 24.2% compared with the nitrogen-free treatment, respectively.

Increasing nitrogen fertilizer application leads to an improvement in yield and yield components. The only factor that decreased with increased water supply was water use efficiency. Grain yield under 100% water requirement was 38% more than that of 50% water requirement treatment. The difference between 100% and 50% water requirement treatments in terms of the biological yield was 49.5% in the first and 24% in the second year. Also, increased nitrogen fertilizer application led to increased grain yield. However, no significant difference was observed between 300 and 400 kg/ha nitrogen fertilizer treatments, especially in the second year. Therefore, a 300 kg/ha fertilizer application is recommended to achieve a suitable yield. Fertilizer use efficiency was affected by water requirement so that nitrogen use efficiency under 100% water requirement supply at a given nitrogen fertilizer level (e.g. 100 kg/ha) was significantly higher than that of 50% water requirement conditions. Under 100 kg/ha nitrogen application, nitrogen use efficiency in 100% water requirement treatment was 111.5 and in 50% water requirement treatment was 74.3 kg/ha. Thus, nitrogen use efficiency declined by 33% due to decreased water use. Therefore, it can be concluded that in conditions where sufficient water is not available for irrigation, farmers should not use excessive amounts of nitrogen fertilizer because it has little efficiency and only leads to environmental pollution and capital waste.

The use of new agricultural technologies such as bio-elicitors is a valuable approach to reduce effects of drought stress. The present study investigated the prospects of enhancing yield and some physiological properties in quinoa under different levels of plant water requirement using elicitors, such as methyl jasmonate (MeJA) and salicylic acid (SA) elicitors.

The aim of this study was to evaluate comparative effect of elicitors MeJA and SA foliar application on the yield and yield component of quinoa under drought stress. This experiment was conducted during 2020-21 cropping season as split plots in a randomized complete block design with three replications at research farm of Zabol University, Iran. The main plots was irrigation regimes at three levels: 100, 75, and 50 percent of crop water requirement and sub-plots of foliar spraying in six levels including: Control (sprayed with distilled water), 70% ethanol, 0.5 mM SA, 0.5 mM MeJA, 1 mM SA and 1 mM MeJA. In this study fertile branches per plant, sterile branches per plant, panicle numbers per m2, seed numbers per panicle, 1000 seeds weight, leaf relative water content, chlorophyll index (SPAD) and seed yield were measured. Determination of irrigation cycle and crop water requirement was based on CROPWAT 8.0 software and Penman-Mantis equation. For plant coefficients used FAO default data. Irrigation planning was determined with 85% efficiency and water volume of each plot calculated using a digital water meter.

The physiological response of the plants in terms of relative water content (RWC) was improved by 100 and 75 percent of crop water requirement conditions. The relative water content of the leaves decreased significantly under the influence of drought stress, although there was no significant difference between the control treatment and the supply of 75% of the water requirement of the plant, by increasing the stress intensity to 50% of the water requirement of the plant, a decrease of 31.6% in the relative water content of the leaves was observed. Additionally, doubling the elicitors concentration increased the yield and non-yield traits. Foliar application of MeJA and SA significantly increased the seed yield and fertile branches and sterile branches per plant, panicle number per m2, seed number per panicle and chlorophyll index treats. The use of 1 mM SA gave the best response after MeJA. Despite providing 50% of the plant's water needs, plants treated with 1 mM methyl jasmonate produced 45% more fertile shoots than plants sprayed with distilled water. Drought stress increased the number of infertile shoots by 77% compared to control plants. Increasing the intensity of drought stress and decreasing water availability decreased the filling rate and ultimately the seed weight. The application of 1 mM concentration of methyl jasmonate and salicylic acid increased the chlorophyll index compared to the control. Based on the results of comparing the averages, the highest level of this trait (46.84) was observed in the concentration of 1 mM methyl jasmonate. The positive effect of methyl jasmonate on the chlorophyll concentration of leaves may be due to the increase in the number and size of chloroplasts. The results showed that the interaction of irrigation and foliar application had a significant effect on all traits except 1000 seeds weight, RWC and chlorophyll index. The highest seed yield (2929.3 kg ha-1) was obtained from 100 percent of crop water requirement (4662 m3 ha-1) with 1 mM MeJA treatment.

Our results showed that impaired water supply of quinoa with significant loss of relative water content endangers cellular health and reduced yield. In general, it can be said that, to achieve maximum yield of quinoa it is possible to use 100% of crop water requirement with 1 mM MeJA foliar application.

Water is one of the most common and at the same time the most important substance on the planet. All kinds of plants in different parts of the earth need more water than any other environmental factor. The main purpose of direct measurements or evapotranspiration calculations is the amount of water required by plants. Knowledge of the water need of plants in each region and its use in agricultural planning plays an important role in water usage. Due to the reduction of fresh water reserves in the world, accurate estimation of evaporation and transpiration and water requirement of plants seems to be important. Therefore, developing an irrigation plan and applying proper irrigation management can reduce the losses caused by water resources. The aim of the current research is to determine the evapotranspiration and plant coefficients of saffron plant and the evapotranspiration of the grass reference plant by two methods, lysimeter and FAO-Penman-Mantith, in Birjand city.
 
The research was carried out in the agricultural year of 2018-2019 in the lysimetry laboratory of the Faculty of Agriculture, Birjand city, for this purpose. The saffron plant was grown in six lysimeters and the grass reference plant in three lysimeters, in the collection of lysimetry laboratories of the Faculty of Agriculture, Birjand University. The growth period of saffron plant was divided into four initial (27 days), development (54 days), middle (40 days) and final (54 days) stages. Irrigation was done daily until the soil moisture reached the agricultural capacity. The irrigation volume was adjusted based on the soil moisture level, the reason for which was mentioned above. The start time of irrigation was determined based on soil moisture and Fc. The end of irrigation was done according to the condition and moisture content of the soil.
The average of evapotranspiration of the grass reference plant by lysimetric and FAO-Penman-Monteith methods was obtained equal to 4.32 and 4.19 mm/day, respectively, and the average of evapotranspiration of the saffron plant during the 175-day growth period was obtained equal to 2.34 mm/day. During different stages of growth, the amount of the average of single crop coefficient was estimated 0.36, 0.66, 0.86 and 0.42, respectively, and the average of dual crop coefficient was estimated 0.37, 0.67, 0.87 and 0.42, respectively. With the passage of time, the amount of evaporation-transpiration of the reference plant has increased, which can be attributed to the long day length and the increase in net solar radiation, with the increase in temperature, the amount of evaporation-transpiration also has increased, so the demand of the plant to receive water increases.
 
Observations indicated that at the beginning of the period, due to high evaporation, this coefficient was clearly obtained from their sum, but in the middle stage, due to the decrease in evaporation and the predominance of transpiration, the coefficient of vegetation in most cases was Sweating has approached and this trend of changes has been the same in all lysimeters. The value of the basic vegetation coefficient (transpiration component) gradually increased after passing through the initial stage and reached the maximum value in the middle stage. The value of the evaporation coefficient from the soil surface (Ke) is the highest after the surface soil layer is wetted by rain or irrigation. As this layer dries, the evaporation coefficient will increase. In the condition that there is no water left in the surface layer of the surface soil, the evaporation coefficient reaches zero. The two-component vegetation coefficient, which is the sum of the transpiration and evaporation components, also decreases gradually. The fluctuations seen in the graph are due to the short irrigation period.

Abiotic environmental stresses such as drought and salinity are important factors in reducing crop yield in many parts of the world (Muscolo et al., 2016). Water scarcity is the most important factor in reducing the production of crops in arid areas. Therefore, it is necessary to pay attention to the sustainable use of water resources, especially in arid and semi-arid regions (Dabhi et al., 2013; Samadzadeh et al., 2020). Introducing new drought-tolerant crops is the main strategy for sustainable crop production in arid regions (Samadzadeh et al., 2020). Besides, deficit irrigation and foliar application of osmolyte compounds such as glycine betaine can be considered to reduce the effect of drought stress on plant growth and yield (Fallahi et al., 2015; Tian et al., 2017).

In this experiment, the effects of water availability and foliar application of glycine betaine (GB) were studied on the growth and yield of quinoa. The experiment was carried out as factorial based on a complete randomized block design with three replicates in Sarayan, south Khorasan province, Iran. Experimental factors were (1) irrigation management regimes (irrigation after 70, 140, and 210 mm pan evaporation) and (2) GB foliar application (0 zero or distilled water and 150 mg. l-1).

There were no significant differences between irrigation levels in terms of many vegetative and reproductive parameters such as plant height, plant dry weight, number of panicles per plant, panicle length, and its dry weight. An increase in water stress severity caused a reduction in biological yield and 1000-grain weight, but seed yield did not decrease. GB application increased the values of plant dry weight, biological yield, chlorophyll index (SPAD), and the number of panicles per plant, while reduced reducing seed yield. Interaction results of experimental factors revealed that the highest biological yield (2533.3 kg ha-1) was obtained by GB and irrigation after 70 mm pan evaporation, while the lowest value (1433.3 kg ha-1) was gained by the no-GB and 210 mm pan evaporation. The highest seed yield values were obtained by 70 and 210 mm pan evaporation (250.7 and 245.4 kg ha-1, respectively) combined with the no-GB application. In general, due to the scarcity of water resources in arid areas, quinoa irrigation after 210 mm pan evaporation can be recommended.

Quinoa had an acceptable resistance to drought stress. Seed yield in this experiment was much lower than the plant's genetic potential, which could be due to improper planting date and density. Therefore, research on other quinoa cultivars, other planting dates, and foliar application of glycine-betaine at other concentrations and times can complement the results of the present experiment.

The proper planting date is known as one of the most important agronomic programs to achieve the optimal yield in crops through increasing adaption of plants to environmental conditions and improving resource use efficiency. The synchronization of growth stages with climatic parameters in terms of rainfall, temperature, and humidity is considered as the main consequence of proper planting dates. One of the most basic methods for improving water consumption patterns in the agriculture sector is the accurate management of cropping and breeding methods, so the implementation of policies to change the pattern of cultivation based on comparative advantage, efforts to reduce the level of crop cultivation requiring high water consumption and developing drought-resistant plants. In this regard, water scarcity is a well-known factor in reducing quinoa yield under arid and semi-arid areas, which can seriously affect crop profitability. Thus, the present study aimed to evaluate the different planting dates and irrigation rounds on physiological traits and growth yield and component yields of quinoa under Mashhad climate.

The current study was conducted at the Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, in 2020. The experiment was designed as a split-plot arrangement based on randomized complete block design with three replications: planting date (July 6th, July 23th, and August 6th) as main plots and water deficit regimes (7, 14, and 21-d intervals) as subplots. The experimental data were analyzed using SAS 9.4. The mean values were statistically compared according to the least significant difference (LSD) test at the level of 5%.

According to the results, decreasing water availability significantly caused an increase in chlorophyll a, chlorophyll b, and carotenoid contents. Also, leaf osmotic potential at the planting date of August 6th significantly decreased up to 39%, compared with the planting date of July 6th. It seems that in the case of increasing temperature, with increasing leaf osmotic potential, the plant resistance to environmental conditions would be improved. The content of soluble carbohydrates as well as the activity of ascorbate peroxidase and peroxidase enzymes were significantly affected by the interaction between planting date and irrigation. The highest amount of ascorbate peroxidase enzyme was observed in the 21-d irrigation cycle and planting date of August 6th. Ascorbate activity increased with increasing drought stress. The highest content of soluble carbohydrates was found on the date of planting on July 23th and the 14-d irrigation cycle. In addition, grain yield at the 21-d irrigation cycle decreased by 25% compared to the 7-d irrigation cycle. Moreover, the highest grain yield was obtained from the planting date of august 6th (544 g.m-2). Water shortage during the root development stage is a limiting factor against the optimal yield of quinoa

Based on the results, a planting date on August 6th with a 14-d irrigation cycle can be recommended to achieve the desired yield of quinoa along with reducing water consumption in the Mashhad region.

Today, the importance of water in maintaining life, especially in arid and semi-arid areas, is not hidden from anyone,.. There are various techniques to determine evaporation and transpiration, which include the use of empirical formulas, lysimeters, remote sensing and satellite methods. It is micro-climatic technologies and methods of using plant transpiration coefficient. This research started in April 2014 and was completed by the middle of September 2014. Studies were conducted on three species of bay leaf (Laurus nobilis L.), rosemary (Rosmarinus officinalis L.) and oleander (Nerium oleander L.) located in the parks and boulevards of all 9 districts of Shiraz municipality. To calculate the rate of evaporation and transpiration of the target plant, first the rate of evaporation and transpiration of the reference plant was calculated using the data of the Shiraz synoptic station and the standard Penman-Mantis-FAO method, and then the coefficient (KL) was calculated based on the California method. This coefficient is the key factor in estimating the water requirement of green space. The highest rate of reference evaporation and transpiration is related to the months of August and July, respectively, and the lowest is related to the months of Bahman and January. . The highest water requirement is between June and October. In order to solve a large part of the lack of water resources mentioned, methods such as recycling and reuse of returned water, using non-conventional water sources (sewage, sewage, gray water, etc.) and surface water and runoff are suggested as solutions.

Maize is the third most important agricultural crop in the world in terms of production, That production and demand has increased by 45% in 2020 compared to 1997. Abiotic stresses in many cultivated areas of this plant have a negative impact on its production and these effects are expected to intensify in the near future.Inefficient use of water in agricultural production in arid and semi-arid regions is one of the most important factors in exacerbating the water crisis and water shortage is a serious limiting factor in agricultural production. The use of technologies to improve water use efficiency in crops is very important for sustainable crop production and food security. Deficit irrigation is a water-saving strategy that is commonly used in arid and semi-arid regions and leads to increased water efficiency. According to studies, Deficit irrigation can save irrigation water, maintain or increase crop production and improve its quality. One of the methods for optimizing water consumption in agriculture is the addition of moisture absorbent such as Zeolite, which by gradually providing absorbed water and nutrients to the soil, play an important role in fertility and preventing water loss. The use of zeolite, especially in sandy soils that exposed to drought stress, can improve growth and final yield by absorbing and controlling moisture release and increasing soil moisture capacity. Because of low rainfall and also limitation of water resources in Birjand region, efficient use of water in agriculture, especially in the production of important cereals such as Miaze, is very important. The aim of this study was to investigate the application of zeolite and deficit irrigation methods for optimal use of water and achieving optimum yield in Maize in this region.

In order to investigate the effect of irrigation and Zeolite on maize, a field experiment was conducted on two planting dates in 2017, factorial based on a randomized complete block design with three replications. The factors including Zeolite in two levels and deficit irrigation in eight levels include: 100% water requirement, 75% water requirement in vegetative stage with: conventional irrigation, Fixed alternate partial root-zone irrigation, nonfixed alternate partial root-zone irrigation, and 75% water requirement in total growth with Fixed alternate partial root-zone irrigation, 50% water requirement in vegetative stage with: conventional irrigation, Fixed alternate partial root-zone irrigation, nonfixed alternate partial root-zone irrigation.

Traits measured on the second date of planting had the highest value compared to the first date. Deficit Irrigation reduced the total dry weight and grain yield, but the use of zeolite improved these indicators. Total dry weight, number of grains per ear, grain yield, harvest index and water use efficiency had the highest value in irrigation control treatment and decreased with deficit irrigation, so that the lowest value in conventional irrigation treatment The basis of 50% of water requirement in the growing season was observed with 23, 26, 38, 27 and 19% reduction, respectively. Zeolite application had a favorable effect on all traits, but the effectiveness of some traits was different during planting dates, so that the rate of yield increase on the second planting date (37%) was higher than the first date (27%). The highest water use efficiency was obtained on the second planting date and Fixed alternate partial root-zone irrigation based on 75% of water requirements during the growing season and total growth with 0.7 and 7.6 due to the increase in observation, had the highest Were the amount. Although the yield decreased in deficit irrigation treatments, but due to the increase in harvest index and water use efficiency, excess water due to under-irrigation can be spent on irrigating more lands and increasing production.

One of the important goals of production in areas with water constraints is to increase the yield per unit of water. According to the results, after the control treatment, the highest harvest index was related to 75% water requirement in vegetative stage with Fixed alternate partial root-zone irrigation treatment. Also, based on water use efficiency, to 75% water requirement in vegetative stage with Fixed alternate partial root-zone irrigation and 75% water requirement in total growth with Fixed alternate partial root-zone irrigation treatments were better than other treatments with a superiority of 0.69 and 7.59% compared to the control treatment. Despite saving 19.84% of water consumption in low irrigation treatments, 50% of water requirement in the growing period, but did not get an acceptable result from this treatment (33.74% reduction in yield and 13.79% efficiency). Water consumption). It seems that the relatively severe lack of water during vegetative growth has caused serious damage to the roots of the plant, which in the later stages of growth, despite the optimal irrigation of the plant could not use the water in the root environment well. Regardless of the reduction in yield and considering the water use efficiency that was obtained in 75 water requirements treatments in the form of atmospheres and constant intermediate stacks in the vegetative period and the whole growth period, it seems that these two treatments for Execution in Birjand region should be more appropriate.

According to the growing human need for food production, using of unconventional water is defined as one of the strategies for overcoming the water crisis in the world. Drainage water recirculation for producing economic sustainable agricultural products can be very useful to management of drainage water environmental impact and adapt with water crisis in the world. For this purpose, overcoming on salinity stresses and preservation of soil quality during cultivation are so important. Studying on salinity effect of irrigation water on wheat yield and soil salts has a long history in the world but genotype and climatic conditions are very influential on the results, so do this research can be very useful. This research has been conducted to determination the best genotype of wheat and analysis of soil behavior in the study of solutes in it.

This research was conducted in 2018-2019 in an experimental farm of AmirKabir Agro-Industry Sugarcane Company using split plot design with randomized complete block with three replications, yield reaction of 20 genotypes of wheat to irrigation with sugarcane drainage water farms was investigated. Also applied water volume, farm water requirement and drainage water effect on soil salts were analyzed. Main plots was irrigation water quality with two quality: 1- fresh water with EC=1.3 dS m-1 and 2- sugarcane drainage water with EC=7.0 dS m-1. Sub plots were 20 genotypes of bread and durum wheat which is cultivated in 8 lines and 20 cm distance. Water requirement was determined by 10-years climate data and wheat crop coefficient and calculated using FAO Penman-Monteith method. Field irrigation management was performed based on water requirement information and considering soil physics, leaching requirements and effective rainfall. Extracted information included volume of applied water, salt and moisture soil samples, water and drainage water quality samples, physical soil specifications, grain yield, biological yield, spike per square meter, grain per spike, 1000-grain weight and flowering date. 

Results showed that using sugarcane drainage water reduced the mean yield by 9.7% and decreased irrigation water productivity from 1.08 to 0.97 kg m-3. There is no significant difference between Bow, Shoele, Narin, Bloudan, Sarang, Irna, Spn and Pishtaz varities for using Karun River and drainage water in terms of grain yield, biological yield, spike per square meter, grain per spike, 1000-grain weight and flowering date, so it can be concluded that these genotypes are stable in different environmental conditions. Stress tolerance index varied from 0.57 to 1.22 among different genotypes. 1-63-31 and Narin genotypes had the highest and the lowest tolerance indices, respectively. Bam and Shoele genotypes were in the mean group with 0.92 and 0.89, respectively. Overall, Sistan, 1-63-31, Bow, Shoele, Sirvan, Sarang, Irna, Khalil, Barat, and Pishtaz with an index above the mean index (0.90) are among the most tolerant and it can be concluded that they can be considered as the most tolerant figures. Also Barat genotype had maximum applied water and total water productivity with fresh water irrigation which were 1.35 and 1.14 kg m-3 and Sistan had maximum water productivity for drainage water in these parameters which were 1.16 and 0.98 kg m-3. Soil results showed that using agricultural drainage water for irrigation not only led to changing farm soil from non-saline to saline condition, it closes to become sodic. Under drainage water cultivation conditions, soil quality will be compromised, which will require new development of irrigation management, leaching and cropping patterns. In these conditions, accurate knowledge of the time and amount of water required for wheat, irrigation with high efficiency and application of appropriate amount of leaching water with proper field drainage, can be effective.

This research was conducted to reaction investigation of various genotypes of wheat in condition of using sugarcane drainage water. Due to the fact that in the middle of autumn and late winter, the drainage of sugarcane fields is low and in this period, most of wheat water requirement is supplied by rainfall and the most important irrigation events start after winter in Khuzestan, so wheat had been chosen for this research. Results showed that yield decrease in drainage water farm for 20 studied genotypes was about 9.8% which is varies between 30.6% for ChamranII to 8.6% for Sistan genotypes. Applying drainage water as irrigation water can cause negative effects on farm soil quality in short term and studying of this behavior by using simulating models can be very useful. For reduction of negative effect of drainage water on soil quality, it is necessary to pay enough attention to the amount and time of irrigation at the last 2 or 3 irrigation events.

This research was carried out in a factorial split plot experiment based on a randomized complete block design with four replications in Semnan Agriculture Research Center, Bastam, central Iran, in 2019. Experimental treatments included irrigation as the main factor at three levels of 100, 75 and 50% of water requirement and sub-factors including cultivar at three levels (Titicaca, Q26 and Q29) and priming at two levels (no priming and hydropriming) as sub-factors. The percentage of water requirement of the plant was calculated using the CROPWAT program and applied from the 6-leaf stage of the plant. The results showed that drought stress reduced leaf area index, 1000-seed weight and grain yield in all three cultivars. Percentage of protein, malondialdehyde, proline, activity of antioxidant enzymes including catalase and ascorbate peroxidase increased in plants under drought stress. Hydropriming increased leaf area index and grain yield. Among the three cultivars tested, hydroprimed plants of Q26 genotype had the highest leaf area index, 1000-seed weight and grain yield compared to the other cultivars. Cultivar Q26 had the highest grain yield when supplied with 75 and 100% of water requirement and Titicaca cultivar had the highest grain yield (1067 kg/ha) in the presence of severe drought stress (i.e. 50% water requirement). In conclusion, Titicaca cultivar was more resistant to drought than other cultivars and cultivation of this cultivar is recommended in Bastam region. In the scope of the research, the application of hydropriming can be suggested to improve the physiological traits of quinoa under drought stress.

Two separate trials were conducted as a factorial design based on randomized complete block design with three replications at the Shahid Moghbeli Agricultural Research Center in Jiroft, Iran in two cropping seasons (2016-17 and 2017-18). In the first trial, the effects of planting method including direct planting and transplanting on different sugar beet cultivars including Palma, Sharif, and Merak were evaluated, and then in the second trial, among studied cultivars, a high yield cultivar (Merak) was selected. Also, the effect of irrigation time (based on 50, 70, and 90% of water requirement) and planting methods on its quantitative and qualitative yield were evaluated. In the first trial, the highest root dry matter, extraction coefficient of sugar, sugar content, root weight, root length, fresh leaf weight, root yield and sugar yield were obtained for Merak cultivar and transplanting. The result of the second trial showed that the irrigation time based on 70% of water requirement led to the highest root and sugar yield along with a significant improvement in water use efficiency. In addition, as transplanting improved root yield and sugar yield, therefore, transplanting method with irrigation at the time of 70% of water requirement is recommended to obtain optimal root yield and sugar yield.

To evaluate rainfall productivity and grain yield of dryland wheat genotypes under different rotation and tillage managements, a split-split plot experiment based on RCBD with three replications was conducted in Dryland Agricultural Research Institute for 4 years (2016-20). Three crop rotations (chickpea-wheat, safflower-wheat, and vetch-wheat) were located in main plots and three different tillage methods (conventional, minimum, and zero tillage) were considered in subplots and two Baran and Azar 2 wheat genotypes were considered in sub-sub plots. Results indicated tillage and crop rotation treatments significantly affect precipitation efficiency. Maximum rainfall productivity was recorded for Baran in zero and minimum tillage systems with forage (vetch) rotation by 0.71 and 0.7 kg/m3. Rainfall productivity under zero tillage treatment during three years of the experiments increased from 0.45 up to 0.67 (approximately 32 %). The highest relative water content, stomatal conductance and harvest index were recorded from Baran in vetch rotation under zero tillage treatment. The highest grain yield was belonged to the vetch, chickpea and safflower rotations by 2231, 2105 and 1991 kg/ha, respectively. With increasing soil water content and improving rainfall productivity in the conservation agriculture system, grain yield was increased by 5% and 8 % under minimum and zero tillage treatments than that of a conventional system. Therefore, in cold rainfed climates, in order to develop in wheat conservation, it is recommended to the application of autumn forage and chickpeas rotation in zero tillage conditions.

Proper planting date and irrigation rate are the most important factors for better use of rainfall and soil moisture and thus increase crop yield. Production of medicinal and aromatic plants and the demand for natural products in the world is increasing, so that the twentieth century has been named as a return to nature and the century of using herbal medicines. Proper growth and development of medicinal plants in agricultural conditions requires knowledge of the ecological characteristics of these plants, careful study of planting techniques and the use of agricultural inputs, especially irrigation, fertilizers, suitable planting and harvesting times and their management. Such factors also affect the amount of secondary metabolites in medicinal plants. The aim of this study was to investigate the effect of four planting dates and four irrigation rates on the yield traits of isabgol in Sarakhs.

In order to investigate the effect of irrigation levels and planting dates on the growth characteristics and yield of isabgol (Plantago Ovata L.) as a medicinal plant, a field experiment was performed in Research station, Sarakhs, Khorasan Razavi province during growth season 2015-16. This experiment was performed as strip plots based on a randomized complete block design with three replications. Irrigation treatments at four levels of 40, 60, 80, and 100% of the water requirements were placed in horizontal plots and four planting dates were on March 5, 2016, March 20, 2016, April 3, 2016 and April 18, 2016 in vertical plots. Irrigation was applied as furrow system at every 7 days. Irrigation treatments were applied at the time of complete establishment of seedlings in 3-4 leaf stage and continued until physiological maturity stage. The amount of irrigation water in each irrigation turn was calculated by AGWAT software. Measured traits included leaf area index, crop growth rate, dry matter accumulation, plant height, number of spikes per plant, number of seeds per plant, 1000-seed weight, grain yield, biological yield and harvest index.

The results of growth indicators showed that the maximum leaf area index (3.4 and 3.3), the crop growth rate (22.12 and 22.18 g m-2 d-1) and the accumulation of dry matter (444.9 and 445.4 g m-2) were obtained in the treatments of 100% and 80% of the water requirements, respectively. Also, the maximum leaf area index and crop growth rate were observed in the treatments of April 18 and April 3 (1.86 and 2). The treatments of March 20 and 5 also had the highest crop growth rate (14 and14 g m-2 d-1) and dry matter accumulation (270 and 261.3 g m-2). The results also showed that the interaction effects on plant height, number of seeds per plant, 1000-seed weight, grain yield, biological yield, and harvest index were significant at the 1% level of probability. Maximum plant height (24.57 cm) was obtained in the 100% of the water requirement and planting date of March 20 treatment. The highest number of seeds per plant (1210.36), grain yield (1891.4 kg), biological yield (5607.8 kg), number of spikes per plant (29.67) and 1000-seed weight (2.05 g) were obtained in the treatments of 80% of water requirement and planting date on March 20.The highest harvest index (36.4%) belonged to the treatment of 100% of water requirement and planting date on March 5.

general, it can be concluded that different characteristics of isabgol plant were affected by planting date and irrigation water amount so that with a delay in planting date and also reducing the amount of irrigation water, growth and yield characteristics were significantly reduced. As a result, deficit irrigation at 80% of the crop water requirement and planting date of March 20 were more effective in saving irrigation water along with a good yield of the isabgol plant compared to 100% of the crop water requirement treatment in the study area.

Sesame is one of the oldest crops. Ethiopia is commonly accepted as the origin of domestic sesame. Sesame is a diploid (2n = 26) plant that grows as a bush. Sesame has a special place among oil plants due to its high oil content and quality as well as its high oil durability. Drought stress is a condition that cells and tissues are in a state where their inflammation is incomplete. In other words, dehydration occurs when the amount of transpiration exceeds the amount of water absorbed. Drought is one of the most important causes of declining agricultural productivity worldwide. Drought has destructive and detrimental effects on different stages of plant growth and reduces yield and yield components in sesame genotypes. Due to the serious problem of limited water resources and drought and its effect on yield reduction, this study to evaluate drought tolerance of sesame genotypes based on tolerance indices to identify and group sensitive, tolerant and resistant genotypes and select resistant genotypes and identify correlations of related traits. Drought tolerance was performed through field studies.

In order to evaluate the genetic diversity of different sesame genotypes under non-stress and drought stress conditions, an Augmented design was conducted in three blocks on 32 genotypes in the southeastern fields of Bojnourd in 2018. Genotypes used were obtained from Karaj Seed and Plant Breeding Research Institute in the amount of 1.5 grams per sample. In this experiment, one plot of land was allocated to the drought stress environment and the other to the stress-free environment. The distance between these two environments was considered to be five meters so that the humidity of the two adjacent environments did not affect each other. With the onset of stress flowering on the target medium, application and irrigation of the dry stress plot based on 200 mm and the non-stress plot based on 100 mm evaporation from the pan was performed. Cumulative evaporation from the pan determined the arrival time of irrigation in each of the environments. SAS PLUS software for calculating variance analysis, principal component analysis and mean comparison, S-PLUS software for drawing 3D and bipod diagrams, SPSS software for calculating the correlation of traits and correlation of tolerance indices and cluster tolerance analysis, respectively, from EXCEL Action was taken.

The studied genotypes showed a significant difference at the level of 1% probability in terms of traits measured under non-stress and drought stress conditions, which indicated genetic diversity and the possibility of selecting drought tolerant genotypes. Darab 14 genotype with 2344 kg.ha-1 had the highest grain yield and the Markazi genotype with 1148 kg.ha-1 had the lowest grain yield in non-stress conditions. Under drought stress conditions, Darab 14 genotype with 1360 kg.ha-1 had the highest grain yield which showed a 58% decrease compared to non-stress conditions. Also, the lowest grain yield was observed in Pakistani genotype with 624 kg.ha-1, which was 53% less than non-stress conditions. Based on the results, Darab 14 genotype showed the highest values of MP, GMP, TOL and STI tolerance indices and the correlation analysis between yield under stress and non stress conditions with drought tolerance indices also showed that STI, GMP, MP and TOL indices the most suitable indices are for screening sesame genotype. Using three-dimensional diagrams of YS, YP and STI, the genotypes were divided into two groups A and C under drought stress conditions. In order to investigate the correlation between different agronomic traits in comparing the grain yield of genotypes and determine their relationships, a simple correlation was calculated in both non-stress and drought stress environments, which showed a positive and significant correlation between yield and yield components in both conditions.

This study showed that comparison genotypes significant differences in terms of measurable traits in non-stress and drought stress conditions. Using MP, GMP, TOL, SSI and STI indices, genotypes can be separated to a large extent based on stress tolerance. Based on these indices and considering the performance in two environmental conditions Darab 14, Shaban and Yekehsaud is were identified as the most tolerant.

In the presence of environmental stresses such as salinity and fertility stresses, water and nutrients less absorbed by the plant. Despite the stresses of salinity and nitrogen deficiency (fertility stress), the determination of the actual water requirement of plants with the AquaCrop model, will be important. Therefore, the aim of this research was to evaluate the AquaCrop model for estimating the soil moisture, evapotranspiration and yield of maize, under the salinity and fertility stresses.

In this research, two treatments of water salinity and nitrogen deficity in four levels and three replications, with a control plot, were implemented as a factorial experiment in a randomized complete of block design. The studied plant was maize with cultivar of 704 Sc and was planted in plots with dimensions of 3 × 3 meters and 1.5 meters apart. In this plan, fertility stress was in the form of nitrogen fertilizer consumption and at four levels. Treatments of N_0، N_1، N_2 and N_3consisted of consumption of 100, 75, 50 and 25% of nitrogen fertilizer based on fertilizer recommendation, respectively. Salinity stress has been applied by irrigation of the plant with saline water. Water salinity treatments were selected based on yield potential of maize at four levels of 100, 90, 75 and 50% (3). According to the above four performance levels, treatments of S_0، S_1، S_2 and S_3 were included; irrigation water with electric conductivity of 0.5, 1.2, 3.5 and 7.5 (ds/m) respectively. Determining the irrigation time, was the same as the moisture content reached the RAW (Readily Available Water) level. Between the two irrigation intervals, the stomatal resistance of maize leaf, was measured by the AP4 prometer device. At the same time as increasing stomatal resistance, RAW was calculated and plots were irrigated. In the days of between two irrigation, was measured the soil moisture content of the plots at the depth of root development. The daily evapotranspiration of the plant, was calculated based on the amount of daily water depletion. For optimal calibration of parameters in the AquaCrop model, was used the method of Generalized Likelihood Uncertainty Estimation (GLUE). Among 16 treatments, 8 treatments were randomly selected for calibration and the rest were selected for validation.

Results were obtained for evaluating the AquaCrop model at the validation stage. The root mean square error (RMSE) of soil moisture simulation, varied from 1.43 to 2.6%. The normalized error value (NRMSE) ranged from 4 to 6 percent. The AquaCrop model showed a similar trend in the evapotranspiration simulation. The root mean square error (RMSE) of evapotranspiration simulation, varied from 1.85 to 2.35 mm. The normalized error value (NRMSE) ranged from 3.5 to 4.5 percent. For yield simulation, RMSE was 0.34 ton. ha-1 and NRMSE was 0.65%. The value of the R^2, EF, and d statistics showed a good correlation between the data and the optimal efficiency of the modeling. Therefore, the results showed that the performance of the model was good in estimating the parameters.

Evaluating the capability of the models is a great help to the agricultural sector planners, in estimation the parameters. In this research, evaluated the estimation of soil moisture content, evapotranspiration and yield of maize, under salinity and fertility stresses with AquaCrop model. The purpose of the model calibration was to nearing the simulated data to the real data (measured in the region). The obtained amounts for NRMSE and R^2 were less than 10% and greater than 0.9, respectively, which indicated the optimal performance of the model in this regard.

Growing season is the part of a year with suitable temperature and sufficient moisture for crop normal growth. Whit recognizing the growing period in the region and crop water requirement can adopt appropriate management to better compromise crop with climate limitations in rainfed agriculture. In the research, the length of growing period in Abhar area using linear interpolation and climatic data was investigated. Besides that, crop water requirement, potential yield, and yield reduction in heavy, medium, and light soil texture for rainfed winter wheat and spring barley were studied using FAO method and long-term synoptic information. Results showed that the length of growing period in terms of moisture was estimated 179 days that its beginning and ending were 1st November and 28th April, respectively. But, considering air temperature and crop critical temperature, from beginning of December to end of February was not involved in the growing period. Therefore, the length of the growing period was declined to 89 days. The humid period was calculated 38 days that its begging and ending were 9th December and 15th January, respectively. Efficient rainfall, crop water requirement, and crop irrigation requirement during winter wheat growing cycle were 89, 611.2, and 522.4 and during spring barley growing cycle were 41.8, 390.3, and 348.5 mm, respectively. Generally, the average, minimum and maximum final yields were estimated for wheat by 1.26, 0.50 and 1.90 Mg ha-1 and for barley by 0.48, 0.18 and 0.80 Mg ha-1, respectively. To mitigate the negative consequences of the shortness of region growing period and its incomplete overlapping with crop growth cycle, measures such as optimum rainwater harvest, sowing in time, improving water use efficiency, selecting drought-resistant or short-season cultivars, and using conservation tillage practices to maintain water are suggested to reach sustainability in rainfed crop production.

In order to improve water utilization management the trends of changes in crop water requirement (CWR), yield, cultivation area and water use efficiency (WUE) of tomato in some regions of Iran evaluated in a 23-year long term (1990-2013) by measuring evapotranspiration (ET) and crop coefficient (Kc). Highest (1137 mm) and lowest (642 mm) CWR of tomato observed in Yazd and Shahrekord cities respectively. Unlike Dezful and Shiraz, this characteristic has a significant increasing trend with a slope of 5.6 mm per year in Fasa. Furthermore, unlike Fasa, tomato yield in Ahvaz, Bandar Abbas, Shahrekord and Yazd has a significant increasing trend. The maximum (49.5 ton/ha) and minimum (19.4 ton/ha) tomato yield and also the maximum (5.6 Kg/m3) and minimum (2.4 Kg/m3) WUE was observed in Fasa and Kerman, respectively. However, the highest reduction (0.1 kg/m3) and highest increase (0.07 kg/m3) in WUE per year was obtained in Ahvaz and Fasa respectively. The results of this study showed that the WUE has a linear relationship with tomato yield. So that the water consumption per 100 kilograms of tomatoes yields per unit of area increased 0.1 kg/m3. While there was no logical relationship between WUE and CWR. By drawing the boundary-line, which represents potential yield against the CWR, high fluctuation of tomato yield in a steady interval of water requirement was estimated. Overall, the lack of a relationship between the WUE and CWR in the range of 600 to 1000 mm was due to yield gap caused by malpractice in the farms.