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In drylands, where the annual precipitation is low and erratic, improving the water storage capacity and the available water in the soil is crucial for crop production. To explore the effect of long-term agronomic management on water storage capacity and available water in the soil, four agronomic management systems were used (including the farmer's management model (FM), the high nitrogen input model (HN), the manure amendment model (MM), and the biochar amendment model (BM)) for eight consecutive years, and the variation in wheat yield and soil hydraulic, physical, and chemical properties in the 0–100 cm soil profile were investigated. The management practices varied in terms of seeding rates, nitrogen (N)-application strategies, and the application of manure or biochar. The results showed that, under the manure amendment model (MM), the wheat yield was increased by 17–35%, and the water-use efficiency was increased by 14–29% when compared to the farmer's management model (FM) and the high nitrogen input model (HN). However, no significant differences in wheat yield and water-use efficiency were found under the biochar amendment model (BM) compared to the HN. The high yield and water-use efficiency under the MM were mainly due to the higher saturated hydraulic conductivity, soil saturated water content, field capacity, and soil available water content, which led to an increase in the available water storage in the 0–100 cm soil profile by 29–48 mm. Furthermore, the MM also improved soil organic matter, porosity, root length density, and root weight density and reduced the soil bulk density, which are beneficial for the improvement of the above soil hydraulic properties. Therefore, it is a practical way to ensure high yield and high efficiency of crops in dryland by improving water storage capacity and the available water in the soil, which can be profoundly regulated by agronomic management. [ABSTRACT FROM AUTHOR]

The handling of the remnants of rice crops in the field is not an easy operation, and farmers prefer burning, which causes air pollution, smog, and disease. This research reports the development of a novel precision crop seeder by handling the remnants of previous crops through mechanization. The precision seeder performed multiple operations in a single path, viz, chop residues, incorporate into soil, make mini trenches, and sow wheat with fertilizer application. The precision seeder has a 2040 mm working width, and specially designed C-type blades are used to shred the crop residue. A multiple-speed gearbox with a gear ratio of 1:0.52 is installed, with a further set of spur gears with 16, 18, and 20 teeth that provide 225, 250, 310, and 350 RPMs to the main rotor. In the middle of the seeder, after the main rotor shaft, 11 V-shaped trencher plates are fixed on the trencher roller for the making of trenches. The trencher roller is powered by star wheels, which showed good results. A zero-tillage-type sharp tip edge novel seeder unit was developed for the precise placement of seed and fertilizer. Seed and fertilizer were placed into the mini trenches through 11 seeder units through a ground wheel calibration system. The field capacity of the precision seeder was 0.408 ha/h and the operational cost was calculated 40.68 USD/ha. The seeder showed good results, with the production of 5028 kg/ha compared to conventional methods. The precision seeder provides a mechanized solution for wheat sowing with minimal operational costs by enhancing organic matter in soil with 13% more yield. [ABSTRACT FROM AUTHOR]

A possible way to increase the operating speed and field capacity of a cultivator-fertiliser is to modify its configuration scheme. According to our hypothesis, placing the fertiliser hopper directly on the tractor frame could reduce the traction resistance of the cultivator-fertiliser and consequently increase its operating speed and field capacity. Validating this hypothesis requires a comparative evaluation of the existing configuration schemes for cultivator-fertilisers. However, there are currently no such comprehensive studies available. This research aims to develop a mathematical model for conducting a comparative theoretical evaluation of various configuration schemes for cultivator-fertilisers. The development of this model incorporated principles from classical and agricultural mechanics. We developed a mathematical model and conducted a theoretical evaluation of existing configuration schemes for cultivator-fertilisers, such as mounting the hopper on a separate trailed chassis, mounting the hopper and tillage working bodies on one frame, and mounting the hopper directly on the tractor frame. The working width of the cultivator-fertiliser was constant and amounted to 6.2 m. The effective engine power of the tractor was taken to be 220 × 103 W. It was found that placing the fertiliser hopper on the tractor frame maximises the field capacity to 3.9 ha∙h−1. The increase in field capacity was 8.9–16.0%. In this case, the fertiliser hopper volume should be 1.89 m3 and travel speed 8.45 km∙h−1. [ABSTRACT FROM AUTHOR]

IntroductionThe challenges of climate change and increasing greenhouse gas emissions have led to consequences such as global warming and successive droughts. Additionally, the rise in agricultural activities has significantly increased the pressure on available water resources. Consequently, it has become essential to consider wastewater resources. To make appropriate management decisions and find solutions to reduce CO2 emissions in the agricultural sector, it is crucial to understand how soil moisture and sources of irrigation affect greenhouse gas (GHG) emissions, particularly CO2. Therefore, the aim of this research was to evaluate the effects of water stress and irrigation management on soil CO2 emissions, water productivity, and soybean yield and yield components.Materials and MethodsThis research was carried out at Sari University of Agricultural Sciences and Natural Resources with latitude (36° 33′ N) and longitude (53° 00׳ E), elevation (14 m, above sea level), average temperature (17.9°C) and total of precipitation (650 mm), during the growing season (2022-2023). The experiment was carried out in the form of a split plot based on a randomized complete block design in three replications in growth season 1402-1403, Sari. Experimental treatments include; the main factor was water stress in three levels ((non-stress, FC100), FC75 and FC50) and the sub factor was irrigation management in two levels (Urban Wastewater (UWW) and Well Water (WW).Results and DiscussionBased on the findings, the highest amount of CO2 emission in the middle and end stages of sampling in 60, 75, 90 and 105 day after sowing in non-stress conditions-FC100 was observed with 535.9, 534.5, 543.6 and 444.5 ppm.min-1, respectively. In addition, its lowest amount was related to water stress-FC50 with 505.3, 499.8, 506.5 and 409.8 ppm.min-1, respectively. The results showed that the highest amount of Co2 emission was assigned to irrigation with urban wastewater with 536.5, 540.1, 538 and 516.9, respectively. Due to the increase in the plant growth rate and approaching the grain maturity, the amount of CO2 emission increased with the increase in temperature, root system development, plant roots respiration and the soil microorganism’s activities. The highest amount of water productivity was observed in the non-stress condition FC100 with a 0.62 kg.m-3. Which compared to water stress conditions-FC75 and FC50 increased by 43.5% and 51.6%, respectively. Also, the results showed that in the non-stress condition-FC100 and irrigation with urban wastewater, the highest pod number (304.8), grain number of per pod (665.1), 100-grain weight (18.7 g), grain yield (1060.4 kg.ha-1) and total dry matter (743.3 kg.ha-1) were obtained. In the condition of irrigation with urban wastewater, the highest number of pods, grain number of per pod, 100-grain weight, grain yield and total dry matter was observed with 234.5, 495.8, 18.5 g, 679.4 kg.ha-1 and 645.7 kg.ha-1, respectively. While their lowest amount was assigned to water stress conditions-FC50 with 218.6, 483.3, 17.7 g, 555.1 kg.ha-1 and 625.5 kg.ha-1, respectively. Optimum soil moisture conditions under non-stress conditions-FC100 and water stress conditions-FC75, especially when irrigating with urban wastewater, increased the yield and yield components by providing nutrients needed by the plant.ConclusionThe results showed that in the early stages of soil sampling, irrigation management (source of irrigation) did not significantly affect the amount of CO2 emission. However, in the middle and final stages of sampling, the growth and development of plant organs and increased soil respiration due to the development of the root system caused the release of CO2. This effect was more pronounced during irrigation with wastewater than with well water. Based on the findings, considering the water scarcity crisis and the challenge of water stress during the soybean growth season, it appears that accurate management and efficient use of wastewater resources is both inevitable and a suitable solution.AcknowledgementSari Agricultural sciences and Natural Resources University (SANRU) financially supported this research under contract number: 02-1397-05.

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Abstract Background The climatic changes crossing the world menace the green life through limitation of water availability. The goal of this study was to determine whether Moringa oleifera Lam. trees cultivated under Tunisian arid climate, retain their tolerance ability to tolerate accentuated environmental stress factors such as drought and salinity. For this reason, the seeds of M. oleifera tree planted in Bouhedma Park (Tunisian arid area), were collected, germinated, and grown in the research area at the National Institute of Research in Rural Engineering, Waters and Forests (INRGREF) of Tunis (Tunisia). The three years aged trees were exposed to four water-holding capacities (25, 50, 75, and 100%) for 60 days to realise this work. Results Growth change was traduced by the reduction of several biometric parameters and fluorescence (Fv/Fm) under severe water restriction (25 and 50%). Whereas roots presented miraculous development in length face to the decrease of water availability (25 and 50%) in their rhizospheres. The sensitivity to drought-induced membrane damage (Malondialdehyde (MDA) content) and reactive oxygen species (ROS) liberation (hydrogen peroxide (H2O2) content) was highly correlated with ROS antiradical scavenging (ferric reducing antioxidant power (FRAP) and (2, 2’-diphenyl-1-picrylhydrazyle (DPPH)), phenolic components and osmolytes accumulation. The drought stress tolerance of M. oleifera trees was associated with a dramatic stimulation of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), ascorbate peroxidase (APX), and glutathione peroxidase (GPX) activities. Conclusion Based on the several strategies adopted, integrated M. oleifera can grow under drought stress as accentuated adverse environmental condition imposed by climate change.

The understanding of soil water retention characteristics, including field capacity, plays a pivotal role in various agricultural studies and practices. This knowledge informs the development of irrigation and drainage schedules, assessments of soil water storage capacity (commonly referred to as plant available water), analyses of solute movement, evaluations of plant growth, and assessments of water stress levels. This study the aim of creating a regression model or equation to predict field capacity of soils in a typical Alfisol, which originated from parent material of basement complex, at the University of Ilorin Teaching and Research Farm. A total of forty-five (45) disturbed and forty-five (45) undisturbed soils samples were collected along a toposequence (upper, middle and bottom slope) at depths: 0 – 30 cm, 30 – 60 cm and 60 – 90 cm. Soil properties of the disturbed and undisturbed samples were ascertained through standard laboratory techniques and/or calculated utilizing established protocols. The measured soil properties include sand, silt, clay, bulk density, total porosity, field capacity and organic matter. A significant negative relationship between field capacity and bulk density (r = -0.582, P≤0.05) was found and a significant positive relationship between field capacity and total porosity (r = 0.581, P≤0.05) was found. A total of four different models were developed for predicting field capacity of the soil. Model four of field capacity was identified as the best model with the highest R2 adjusted value of 0.4494. The model explains 45% of variance in the mean square errors of field capacity with sand, bulk density, silt and organic matter contributing statistically to the model.

Available water capacity (AWC), field capacity (θFC), and permanent wilting point (θPWP) are regarded as key physical soil health indicators that directly capture the soil's capacity to store plant available water but are expensive components of a comprehensive soil health analysis. To reduce costs, pedotransfer functions for θFC, θPWP, and AWC were developed from a dataset of 7,232 soil samples with texture, soil organic matter (SOM), permanganate-oxidizable carbon, soil respiration, AWC, θFC, θPWP, wet aggregate stability, and extractable potassium, magnesium, iron, and manganese. Three functions were developed for each property: a full random forest (RF) model containing all variables, a reduced RF model and a multiple linear regression model containing texture and SOM. Pedotransfer functions were validated with an independent dataset that contained 1,406 samples. The full RF models for θFC, θPWP, and AWC reduced the root mean square error (RMSE) by 16.3, 13.3, and 12.8%, compared to multiple linear regression models, respectively. Furthermore, the full RF models for θFC, θPWP, and AWC reduced RMSE by 11.6, 6.7, and 12.8%, compared to the reduced RF model, respectively. Permanganate-oxidizable carbon, wet aggregate stability, and extractable magnesium, potassium, and iron were useful novel predictor variables for improving prediction of θFC and AWC. AWC was sensitive in 20/57 long-term experiments, and full RF models were able to replicate 5/20 of those significant results. New RF pedotransfer functions for θFC, θPWP, and AWC can enhance prediction compared to traditional modeling techniques, fits into existing interpretative frameworks, and improves cost-effectiveness of comprehensive assessments of soil health. [ABSTRACT FROM AUTHOR]

The Sunn pest, Eurygaster integriceps Puton (Heteroptera: Scutelleridae), is one of the most important pests of wheat crops in Iran and the Middle East. Chemical control by high-volume spraying is the most common method of controlling this pest. The current ground sprayers lack advanced spraying technologies, which results in low efficiency. This study aimed to investigate the efficacy of using an Unmanned Aerial Vehicle (UAV) sprayer for the chemical control of wheat Sunn pest. The effectiveness, field capacity, and costs of chemical insecticide application were compared between the UAV sprayer and the Very Low Volume (VLV) Knapsack Sprayer (KS). We found that the chemical control effectiveness of the two spraying methods was not significantly different. The UAV sprayer and the VLV knapsack sprayer had an effectiveness percentage of more than 95%. The UAV sprayer was better than the other in terms of field capacity, insecticide dosage ml ha-1, spray volume L ha-1, reduced drift, and the probability of the operator exposure. The field capacities of the UAV sprayer and the VLV knapsack sprayer were 3.75 and 0.5 hectares per hour, respectively, and the spray volumes were 14.6 and 30.0 L ha-1, respectively.5.5 and 0.8 hectares per hour, respectively, and the spray volume was 14.6 and 30.0 L ha−1, respectively. [ABSTRACT FROM AUTHOR]

Background: The climatic changes crossing the world menace the green life through limitation of water availability. The goal of this study was to determine whether Moringa oleifera Lam. trees cultivated under Tunisian arid climate, retain their tolerance ability to tolerate accentuated environmental stress factors such as drought and salinity. For this reason, the seeds of M. oleifera tree planted in Bouhedma Park (Tunisian arid area), were collected, germinated, and grown in the research area at the National Institute of Research in Rural Engineering, Waters and Forests (INRGREF) of Tunis (Tunisia). The three years aged trees were exposed to four water-holding capacities (25, 50, 75, and 100%) for 60 days to realise this work. Results: Growth change was traduced by the reduction of several biometric parameters and fluorescence (Fv/Fm) under severe water restriction (25 and 50%). Whereas roots presented miraculous development in length face to the decrease of water availability (25 and 50%) in their rhizospheres. The sensitivity to drought-induced membrane damage (Malondialdehyde (MDA) content) and reactive oxygen species (ROS) liberation (hydrogen peroxide (H2O2) content) was highly correlated with ROS antiradical scavenging (ferric reducing antioxidant power (FRAP) and (2, 2'-diphenyl-1-picrylhydrazyle (DPPH)), phenolic components and osmolytes accumulation. The drought stress tolerance of M. oleifera trees was associated with a dramatic stimulation of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), ascorbate peroxidase (APX), and glutathione peroxidase (GPX) activities. Conclusion: Based on the several strategies adopted, integrated M. oleifera can grow under drought stress as accentuated adverse environmental condition imposed by climate change. [ABSTRACT FROM AUTHOR]

Introduction Organic matter is one of the important indicators of soil quality. Organic matter increases water retention in the soil and helps to transport water and air in the soil. Organic matter increases crop growth and provides nutrients needed by plants and soil microorganisms. The amount of soil organic matter in nature depends on factors such as climate, soil properties, and agricultural management, especially in the plowing stage. This is although in many cultivated and undisturbed soils, the amount of soil organic matter reaches a constant value after some time and becomes balanced.On the other hand, most regions of Iran the arid and semi-arid and have low organic matter. The chemical composition of organic matter is approximately 50% of carbon, 5.0 % of nitrogen, 0.5% of phosphorus, 0.5% of sulfur, 39% of oxygen, and 5.0% of hydrogen, and these values change from one soil to another. The management of compost and plant waste is one of the most essential aspects of soil fertility management in the direction of sustainable agriculture. The research results showed that organic matter and carbohydrates are two factors related to the stability of soil structure. Considering the role and effect of using organic fertilizers (from animal sources and urban waste compost) on the physical characteristics of the soil, it is necessary to improve the productivity of soil and water, changes in the physical characteristics of the soil in different crop management (rotation) in fixed plots and in several years to be reviewed and evaluated consecutively. Materials and Methods This research has been done to investigate the effect of applying organic manure from animal sources and urban waste compost in different and conventional crop rotations in fixed plots and also to investigate the changes in the physical characteristics of the soil due to the application of the following treatments in Alborz Province (at the research station of the Soil and Water Research Institute, Karaj) was implemented from November 2016. After planting wheat in 2016 and harvesting it in 2017, the land alternated with fallow. Wheat was planted again in the fall of 1997 and corn was planted in July 1998. In the fall of 1998, wheat was planted again and then the land was alternated with fallow. This research was conducted in the form of randomized complete blocks in five treatments and three replications in plots with an area of 200 square meters. The treatments include 1- no planting (T1), 2- control without fertilizer use (T2), 3- application of nitrogen, phosphorus, and potassium chemical fertilizers based on soil test (T3), 4- annual application of 20 ton/h of animal manure (T4) and annual application 20 ton/h of compost (T5). By taking soil samples from the surface layer, the physical characteristics of the soil, including field capacity, permanent wilting point, bulk density, final infiltration of soil, and aggregate stability of soil were measured in different treatments. Soil physical characteristics were measured after harvesting each product from a depth of 0-30 cm in three replicates. By removing the soil surface layer, the aggregate stability was determined by the wet sieve method. Results and Discussion Treatments T1, T2, and T3 did not show significant changes in field capacity. The mean values of the field capacity of these treatments T1, T2, and T3 are about 17.8% and the treatment using animal manure (18.1%) and compost (18.3%) increases the field capacity by about 1.0 and 2.0 %, respectively, compared to the average treatments without the use of organic fertilizers. The values of bulk density changes in the treatments for the desired periods are not significant and it indicates that there is no specific trend in each period due to the changes in soil surface conditions for the treatments. The values of changes in the soil aggregate stability values have become significant only in the treatments of organic fertilizer consumption (from animal sources and compost) in the desired periods. The soil aggregate stability index in the treatment of using compost and manure increased by 27 and 18%, respectively, compared to the average of treatments without fertilizer use (1.1 mm), which indicates the role of organic fertilizer use in increasing the aggregate stability. The average final infiltration rate in the treatments without using fertilizer is about 28.1 mm h-1 and the average rate of final infiltration in the treatments using manure and compost is about 32.7 and 33.3 mm h -1, respectively. The average rate of final infiltration in the treatments using manure and compost has increased by about 16 and 19%, respectively, compared to the average of other treatments. Conclusion According to the obtained results and the changes in the physical characteristics of the soil affected by the use of manure and compost in the cultivation periods, the role of the use of these materials in improving the physical characteristics of the soil is generally evident. The average bulk density of treatments T1 to T5 was equal to 1.47, 1.52, 1.54, 1.54, and 1.54 g cm³, respectively, indicating a relative increase in bulk density in organic fertilizer treatments. The soil aggregate stability index in the treatment of using compost and manure increased by 27 and 18%, respectively, compared to the average of treatments without fertilizer use, which indicates the role of organic fertilizer use in increasing the aggregate stability. The average final infiltration rate in manure and compost treatments has increased by about 16 and 19%, respectively, compared to the average of other treatments, which indicates the effect of manure and compost application in increasing the final soil infiltration rate. Because for each crop rotation, the soil is subjected to tillage operations, therefore destruction of the surface layer of the soil (with more organic matter) and as a result intensifying the activity of microorganisms, from the effect of organic matter on the characteristics, the physical properties of the soil are reduced and it even causes that no special trend can be seen in the physical characteristics of the soil during the cultivation periods. Therefore, it is necessary to use a set of management strategies to improve the amount of organic matter or the physical characteristics of the soil. [ABSTRACT FROM AUTHOR]

Field capacity (FC) is an important soil hydraulic concept in soil science and irrigation management. It is generally determined from soil water content in a soil layer when soil profile reaches a steady pressure head or negligible drainage flux from an initially saturated soil. However, the proposed criteria are mainly tested for uniform soils and vary with soil textures. To quantify FC in layered soils, a Richards equation-based model was used to describe water flow in fine-textured soils with a coarse interlayer. With calibrated soil hydraulic parameters for loam and sand from infiltration measurements, drainage from saturation was simulated in the loam with a sand interlayer. A relative drainage rate (δ) was defined as a function of water storage and drainage flux to analyze soil water status at FC. Soil water content in the upper loam layer of layered profiles was improved compared with that in the uniform loam, which was negatively correlated with buried depth but positively correlated with thickness of the sand layer for a specified δ. Under different buried depths and thicknesses, soil water content decreased with the decline of δ and decreased rapidly as δ reduced to 1 % d−1. The drainage flux at δ = 1 % d−1 changed within a range of 0.056–0.26 cm d−1, and soil water content reached to 0.278–0.346 cm3 cm−3, which accounted for 70–87 % of the saturated water content of loam. Although the FC in the upper fine-textured soil layer varied for different buried depths and thicknesses of coarse interlayer, the proposed dynamic method is reliable and universal to estimate the FC in the above layered soils at δ = 1 % d−1. An empirical equation was also developed to calculate the FC in fine-textured soils with different buried depths and thicknesses of a coarse interlayer based on the critical δ value.

Introduction Organic matter is one of the important indicators of soil quality. Organic matter increases water retention in the soil and helps to transport water and air in the soil. Organic matter increases crop growth and provides nutrients needed by plants and soil microorganisms. The amount of soil organic matter in nature depends on factors such as climate, soil properties, and agricultural management, especially in the plowing stage. This is although in many cultivated and undisturbed soils, the amount of soil organic matter reaches a constant value after some time and becomes balanced.On the other hand, most regions of Iran the arid and semi-arid and have low organic matter. The chemical composition of organic matter is approximately 50% of carbon, 5.0 % of nitrogen, 0.5% of phosphorus, 0.5% of sulfur, 39% of oxygen, and 5.0% of hydrogen, and these values change from one soil to another. The management of compost and plant waste is one of the most essential aspects of soil fertility management in the direction of sustainable agriculture. The research results showed that organic matter and carbohydrates are two factors related to the stability of soil structure. Considering the role and effect of using organic fertilizers (from animal sources and urban waste compost) on the physical characteristics of the soil, it is necessary to improve the productivity of soil and water, changes in the physical characteristics of the soil in different crop management (rotation) in fixed plots and in several years to be reviewed and evaluated consecutively. Materials and Methods This research has been done to investigate the effect of applying organic manure from animal sources and urban waste compost in different and conventional crop rotations in fixed plots and also to investigate the changes in the physical characteristics of the soil due to the application of the following treatments in Alborz Province (at the research station of the Soil and Water Research Institute, Karaj) was implemented from November 2016. After planting wheat in 2016 and harvesting it in 2017, the land alternated with fallow. Wheat was planted again in the fall of 1997 and corn was planted in July 1998. In the fall of 1998, wheat was planted again and then the land was alternated with fallow. This research was conducted in the form of randomized complete blocks in five treatments and three replications in plots with an area of 200 square meters. The treatments include 1- no planting (T1), 2- control without fertilizer use (T2), 3- application of nitrogen, phosphorus, and potassium chemical fertilizers based on soil test (T3), 4- annual application of 20 ton/h of animal manure (T4) and annual application 20 ton/h of compost (T5). By taking soil samples from the surface layer, the physical characteristics of the soil, including field capacity, permanent wilting point, bulk density, final infiltration of soil, and aggregate stability of soil were measured in different treatments. Soil physical characteristics were measured after harvesting each product from a depth of 0-30 cm in three replicates. By removing the soil surface layer, the aggregate stability was determined by the wet sieve method. Results and Discussion Treatments T1, T2, and T3 did not show significant changes in field capacity. The mean values of the field capacity of these treatments T1, T2, and T3 are about 17.8% and the treatment using animal manure (18.1%) and compost (18.3%) increases the field capacity by about 1.0 and 2.0 %, respectively, compared to the average treatments without the use of organic fertilizers. The values of bulk density changes in the treatments for the desired periods are not significant and it indicates that there is no specific trend in each period due to the changes in soil surface conditions for the treatments. The values of changes in the soil aggregate stability values have become significant only in the treatments of organic fertilizer consumption (from animal sources and compost) in the desired periods. The soil aggregate stability index in the treatment of using compost and manure increased by 27 and 18%, respectively, compared to the average of treatments without fertilizer use (1.1 mm), which indicates the role of organic fertilizer use in increasing the aggregate stability. The average final infiltration rate in the treatments without using fertilizer is about 28.1 mm h-1 and the average rate of final infiltration in the treatments using manure and compost is about 32.7 and 33.3 mm h-1, respectively. The average rate of final infiltration in the treatments using manure and compost has increased by about 16 and 19%, respectively, compared to the average of other treatments. Conclusion According to the obtained results and the changes in the physical characteristics of the soil affected by the use of manure and compost in the cultivation periods, the role of the use of these materials in improving the physical characteristics of the soil is generally evident. The average bulk density of treatments T1 to T5 was equal to 1.47, 1.52, 1.54, 1.54, and 1.54 g cm-³, respectively, indicating a relative increase in bulk density in organic fertilizer treatments. The soil aggregate stability index in the treatment of using compost and manure increased by 27 and 18%, respectively, compared to the average of treatments without fertilizer use, which indicates the role of organic fertilizer use in increasing the aggregate stability. The average final infiltration rate in manure and compost treatments has increased by about 16 and 19%, respectively, compared to the average of other treatments, which indicates the effect of manure and compost application in increasing the final soil infiltration rate. Because for each crop rotation, the soil is subjected to tillage operations, therefore destruction of the surface layer of the soil (with more organic matter) and as a result intensifying the activity of microorganisms, from the effect of organic matter on the characteristics, the physical properties of the soil are reduced and it even causes that no special trend can be seen in the physical characteristics of the soil during the cultivation periods. Therefore, it is necessary to use a set of management strategies to improve the amount of organic matter or the physical characteristics of the soil.

Indonesia is a significant producer of shallots, and the country frequently cultivates three distinct varieties: Bima, Trisula, and Sumenep. Each cultivar exhibits distinct characteristics, specifically when grown under suboptimal conditions. Several studies showed that insufficient watering intervals (WIs) can lead to drought stress, while excessive levels often lead to inundation. To investigate the effects of cultivar and WI on shallot growth and quality, this study employed a split-plot design with main plots and subplots with four repetitions. The main plots consisted of cultivars (Bima, Trisula, and Sumenep), while the subplots comprised WIs (once in 1 day, 2 days, and 3 days). The results showed that there was an effect of interaction between cultivars and WIs on growth (proline [126.15 mg 100 g−1]) and quality (quercetin [3.8739 mg g−1], rutin [0.2080 mg g−1], and kaempferol [1.209 mg g−1]). However, there was no effect on the number of tillers, shoot/root ratio, water content, number of tubers, tuber weight, and total flavonoid.

This research was conducted to investigate the effect of planting densities on some morphophysiological characteristics of sports turfgrass under low water stress conditions. The experiment was carried out in the form of split plots, based on a randomized complete block design with three replications. Treatments included low water stress at three levels of 90 (control), 60 and 30% of field capacity (FC), and planting density of 20, 30, and 40 g seed/m2. Seeds were planted according to the desired densities in plots measuring 2×3 m2. Two months after planting, low water stress was applied for three weeks. The results showed that the treatments had a significant effect on the evaluated traits. The highest fresh and dry weight of the aerial part, leaf length, and total chlorophyll content was observed in 90% FC and the density of 20 g seed/m2 treatment. The highest root fresh and dry weight, root volume, and total carbohydrates were obtained in 30% FC and density of 20 g seed/m2 treatment. Moreover, the highest proline content was in 30% FC and density of 40 g seed/m2 treatment. According to the results, the planting density of 20 g seed/m2 and 90% FC had a more favorable effect on the vegetative and physiological indicators of sport turfgrass.

Saffron is a valuable plant that generally faces water stress in its life cycle. Therefore, in order to investigate the effect of corm priming of saffron on the physiological and corm characteristics of this product under drought stress conditions, a split plot experiment was carried out based on a randomized complete block design with three replications. The experimental treatments included two levels of irrigation based on 70 and 50% of field capacity as a main plot and six corm priming treatments, including no priming (control), potassium nitrate, auxin, gibberellin, silicon dioxide nanoparticles, and hydro-priming as subplot. The results showed that the increase of intensity of drought stress from 70 to 50% of field capacity caused an increase of 38.5%, 59.1%, and 57.3% in the amount of chlorophyll a, chlorophyll b, and carotenoids, respectively, and a decrease of 32.6% and 20% to the ratio of chlorophyll a.b -1 and the amount of protein respectively. Priming of the mother corm with two hormones auxin and gibberellin, significantly increased the amount of protein, and the highest weight of the daughter corm was observed at gibberellin hormone treatment at the rate of 3.72 grams per plant. The two treatment levels of gibberellin and auxin hormones, under conditions of medium drought stress, significantly resulted in the highest number of daughter corms and gibberellin hormone and also significantly increased the diameter of daughter corm at the rate of 28 mm. In general, corm priming of saffron with two hormones gibberellin and auxin is recommended to improve the physiological traits and tuber characteristics, especially under water stress conditions. [ABSTRACT FROM AUTHOR]

One of the most significant challenges in arid and semi-arid regions is the presence of abiotic environmental stresses, particularly drought stress, which affects the growth and development of plants. Elaeagnus angustifolia, as a species resistant to drought stress, is utilized for revegetation of barren areas, soil conservation, and creation of green spaces. An experiment was conducted in Semnan city to assess the impact of varying levels of drought stress on one-year-old elm seedlings using a completely randomized design. The experiment included four stress levels: control (100% available water), mild stress (75% available water), moderate stress (50% available water), and severe stress (25% available water). The results indicated that there was no significant difference between drought stress levels regarding the height and diameter of seedlings, while significant differences were observed in leaf number, vitality, root dry weight, and stem dry weight. The control group and mild stress conditions exhibited the highest number of leaves (25), freshness (>95%), root dry weight (>5 grams), and stem dry weight (>8 grams). As drought stress levels increased, there was a noticeable decrease in the number of leaves, survival rate, freshness, root dry weight, and stem dry weight. Regarding the vitality of seedlings, it was found that vitality remained at 100% in all drought stress levels except for severe stress, where vitality gradually decreased to zero after 7 months. Generally, the results demonstrated that the best outcome, which included acceptable growth and optimal water consumption, was attainable under mild stress conditions (75% available water). Indeed, this species demonstrated the ability to endure moderate drought stress conditions (50% available water) with a 100% survival rate. Additionally, there was no significant difference in terms of the stem dry weight (7.5 grams) compared to the control sample. This indicates that the elm species is resilient to water stress and can be effectively utilized for planting in green spaces within dry climate regions. [ABSTRACT FROM AUTHOR]

Climate changes and the cost of irrigation water in semi-arid areas seriously reduce the availability of water for irrigation. The optimal allocation of water resources to irrigation and limit water overexploitation are necessary in these regions. A field trial aimed to evaluate irrigation regimes (60, 80, and 100% based on field capacity, abbreviated as FC60, FC80 and FC100) and organic fertilizer (0, 15, and 30 t ha-1 farmyard manure, abbreviated as FYM) on two rapeseed varieties (Hydromel and Nathalie) in the semi-arid region of Qazvin, Iran. The highest lateral growth (branch number) was observed in the Hydromel cultivar with the application of 15 and 30 t ha-1 farmyard manure (FYM30 and FYM15) under FC100 and FC80 conditions. Comparison of lateral growth between the cultivars showed that Nathalie cultivar was less affected by FYM and irrigation. The chlorophyll content decreased under FC60; however, no significant difference was observed between FC80 and FC100. The maturity of Nathalie was earlier than that of Hydromel. However, the use of FYM significantly extended the days to maturity in Hydromel. Although the silique length of the Nathalie cultivar was 13% less than Hydromel, this component significantly decreased in Hydromel under water deficit conditions (FC80 and FC60). The highest number of siliques was recorded in the Hydromel under FYM30+FC100 and FYM30+FC80. The 60% irrigation regime caused a significant reduction in the number of siliques. Although the seed yield of Hydromel was higher than that of Nathalie, the stability of the seed yield in Nathalie was more evident under FC80 and FC60. Overall, the obtained results showed that the Hydromel variety can produce an acceptable yield under FYM30+FC80 and save 20% in water consumption. The results indicated that the 60% irrigation regime was a stressful deficit irrigation and cannot be recommended for this semi-arid region.

IntroductionPlants are exposed to various environmental stresses during growth and development under natural and agricultural conditions. Drought is one of the most severe abiotic stresses that greatly affects plant yield. Metabolic changes under stress cause the morphological and physiological changes in the plant which may eventually lead to reduced yield. Barley is one of the most important cereals which a large part of the human population in many parts of the world are dependent on it as a source of food and animal feed.Materials and methodsIn order to investigate the effects of drought stress on some morphological and physiological traits in barley as one of the most important crop, this experiment was carried out in the greenhouse of the agriculture faculty, Ferdowsi University of Mashhad in 2019 in a factorial based on a randomized complete block design with three replications. Experimental factors were included: different levels of drought stress including 100% of field capacity (control or no stress), 80, 60 and 40% of field capacity and two barley cultivars containing semi-sensitive (Fajr30) and drought tolerant (Dasht). First, the seeds of both cultivars were planted in trays filled with coco peat, perlite and sand, and after two weeks, the seedlings were transferred to pots filled with garden soil. The pots were watered daily and after one month (4 to 6 leaf stage) until the end of the growing season, they were subjected to drought stress treatments. During the vegetative stage, morphological traits such as plant height (from crown to end of plant), stem diameter, number of leaves, number of tillers, leaf area and number of stomata below and above the leaf were examined using common methods. Physiological traits including proline, soluble sugars, photosynthetic pigments and antioxidant enzymes (catalase and peroxidase) were also measured. Analysis of variance was performed using JMP statistical software version 8 and the mean of treatments was compared using LSD test at the level of 5%.Results and discussionThe results of this experiment showed that the effect of cultivar and drought stress were significant for many of the studied traits. The highest plant height, stem diameter, number of leaves and tillers and leaf area index were observed in plants without stress (100% FC), which was significant compared to other stress level. Also, the comparison of the two cultivars showed that Dasht, as a drought tolerant cultivar, has more leaves and tillers but less leaf area and stomata than the semi-sensitive cultivar Fajr30. In other words, the tolerant cultivar produces more leaves but smaller under stress condition which finally reduces the leaf area compared to the sensitive cultivar. This can be a good solution for drought resistance through reduce evaporation from the leaf surface as well as shading. In addition, osmotic regulators such as proline and soluble sugars and the activity of antioxidant enzymes including catalase and peroxidase increased under drought stress and it was higher in tolerant cultivar. In fact, it seems that tolerant cultivar can tolerate drought stress through activating their immune system by producing osmoprotectant and increasing the activity of antioxidant enzymes.ConclusionIn general, results showed that proline, soluble sugars and antioxidant enzymes play a role in the mechanism of stress tolerance and their metabolism is affected by drought stress. The results of this experiment suggest that the accumulation of these osmoprotectans and morphological changes can be part of the drought resistance mechanisms in the drought tolerant genotype of barley, which can ultimately be used in breeding programs to improve drought tolerance. In general, the results of this experiment showed that both barley cultivars responded to drought stress, but Dasht cultivar showed more tolerance in these conditions.

In drylands, where the annual precipitation is low and erratic, improving the water storage capacity and the available water in the soil is crucial for crop production. To explore the effect of long-term agronomic management on water storage capacity and available water in the soil, four agronomic management systems were used (including the farmer’s management model (FM), the high nitrogen input model (HN), the manure amendment model (MM), and the biochar amendment model (BM)) for eight consecutive years, and the variation in wheat yield and soil hydraulic, physical, and chemical properties in the 0–100 cm soil profile were investigated. The management practices varied in terms of seeding rates, nitrogen (N)-application strategies, and the application of manure or biochar. The results showed that, under the manure amendment model (MM), the wheat yield was increased by 17–35%, and the water-use efficiency was increased by 14–29% when compared to the farmer’s management model (FM) and the high nitrogen input model (HN). However, no significant differences in wheat yield and water-use efficiency were found under the biochar amendment model (BM) compared to the HN. The high yield and water-use efficiency under the MM were mainly due to the higher saturated hydraulic conductivity, soil saturated water content, field capacity, and soil available water content, which led to an increase in the available water storage in the 0–100 cm soil profile by 29–48 mm. Furthermore, the MM also improved soil organic matter, porosity, root length density, and root weight density and reduced the soil bulk density, which are beneficial for the improvement of the above soil hydraulic properties. Therefore, it is a practical way to ensure high yield and high efficiency of crops in dryland by improving water storage capacity and the available water in the soil, which can be profoundly regulated by agronomic management.

Preferential pathways in soil lead to nutrient leaching and groundwater contamination. However, the evolution of preferential flow with straw application remains uncertain. This study aims to experimentally determine the hypothesis that, depending on how it is applied, straw will either promote or inhibit the movement of soil preferential flow. Treatments with straw application rates of 0, 5, 10, and 15 t/ha and decomposition time points of 0, 60, and 240 d were set up for the potassium iodide–starch dye-tracer method. The results showed that the straw decomposition rate slowed down in the later stages. At 0 d, the preferential flow coefficients of straw application of 0, 5, 10, and 15 t/ha were 0.13, 0.14, 0.23, and 0.17, respectively. At 60 d, the preferential flow coefficients were approximately 0.17, 0.11, 0.22, and 0.12. Soil properties and irrigation quality improved at 0 d and 60 d. However, a marked increase of 0.31, 0.35, and 0.17 in the preferential flow coefficient was observed at 240 d. Soil properties and irrigation quality deteriorated at 240 d. These results indicate that the effect of straw incorporation and decomposition on preferential flow was initially inhibited and subsequently promoted. Soil properties and irrigation quality were initially improved and subsequently deteriorated. The study serves as a reference for rational utilization of agricultural residuals and scientific irrigation, suggesting that the optimal method of straw incorporation should be adopted based on the growth cycle of the crops. [ABSTRACT FROM AUTHOR]

Introduction Cross breeding processes including targeted crossings to increase drought tolerance, can be considered as a safe and permanent solution to reduce the harmful effects of drought stress on plants. Therefore, two issues of pistachio as a strategic crop in the country and location of Iran in arid and semi-arid region necessitated research in order to achieve rootstocks drought-tolerant hybrids are necessary. Materials and methods The experiment was conducted as factorial based on a Completely Randomized Design with four replications in the research greenhouse of Gorgan University of Agricultural Sciences and Natural Resources during 2018-2019. The treatments were consisted of 10 pistachio genotypes Ahmad Aghaei, Akbari, Sorkheh Hosseini, Garmeh, Fandoghi and interspecific hybrids (Ahmad Aghaei×Integerrima, Akbari×Integerrima, Sorkheh Hosseini× Integerrima, Garmeh×Iintegerrima and Fandoghi×Integerrima) and three levels of drought including control (field capacity), mild stress (65% of field capacity) and Severe stress (30% of field capacity) were applied on 3 months old the seedlings for 84 days. Results and Discussion According to the results, fandoghi genotype showed a higher malondialdehyde concentration in leaves (280.23 %), while the hybrid genotypes of Sorkheh Hosseini×Integerrima, Ahmad Aghaei- ×Integerrima and Akbari× Integerrima showed a lower malondialdehyde concentration in leaves by 70.18, 76.70, 81.03 % respectively compared to the control. Several osmotic mechanisms are carried out by plants, especially pistachios, in stressful conditions to reduce the effects of drought stress. In fact, these mechanisms have enabled plants to withstand the damages caused by drought and have made plants able to recover their biochemical and physiological functions faster after removing the stress factor. For example, a general physiological mechanism adopted by plants to cope with abiotic stresses is the production of large amounts of low molecular weight, watersoluble, non-toxic organic compounds even in high amounts called osmolytes. One of the most important of them is proline. Therefore, the genotypes with higher amount of proline can be more tolerant to drought conditions. The next osmolyte is glycine betaine, which has a significant protective role in the stability of enzymes and the structure of plasma membranes when faced with drought stress. Therefore, glycine betaine plays a significant role in the resistance of plants to stress through the protection of enzymes, the photosynthetic apparatus, the elimination of free radicals, the preservation of membrane integrity, the protection of large molecules, and as a nontoxic compatible osmolyte. It has an environment. Carbohydrates also increase membrane stability in response to drought stress. Therefore, the accumulation of carbohydrates in the osmotic responses of plants is one of the factors that can prevent disorders in the cell membrane. In addition, phenols are also one of the antioxidant mechanisms of plants in drought stress conditions, because such compounds act as scavengers of reactive oxygen species and thus stabilize membrane, cells and prevent lipid peroxidation. Malondialdehyde is also a decomposition product of unsaturated fatty acids and hydroxides and is used as a suitable marker for lipid peroxide. Therefore, the amount of malondialdehyde obtained from the peroxidation of membrane lipids is used as an indicator for oxidative damage in most cases. Conclusion Based on the results of the present research, it seems that it is possible to use the hybrids of Sorkhe Hosseini × Integerrima, Ahmad Aghaei × Integerrima, and Akbari× Integerrima as drought-tolerant genotypes in dry areas. Therefore, based on the results of the present research, it seems that the plants in question can be used as drought tolerant genotypes in arid regions. [ABSTRACT FROM AUTHOR]

Background and objectives: Given the low precipitation and frequent occurrence of droughts in Iran, it is crucial to devise basic plans and identify new methods to mitigate the effects of drought on fodder production resources. Saltbush (Atriplex canescens (Pursh) Nutt.), extensively cultivated in Iran for desert restoration, is one such plant. Methodology: To investigate the effects of nano-zinc oxide and its efficacy in creating resistance to drought stress on the growth and physiological variables of one-year-old saltbush seedlings, an experiment was conducted in a completely randomized design with four replications. The experimental treatments included seed nano priming using nano-zinc oxide at concentrations of 0, 30, 100, 300, and 1000 mg/liter, and drought stress at four levels of field capacity: 20%, 40%, 60%, and 80%. Results: The results showed that as soil moisture decreased, the growth characteristics of seedlings, including the number of branches, leaves, collar diameter growth, fresh and dry weight of aerial parts, and fresh and dry weight of roots, decreased. The highest values of these characteristics were observed in the 80% treatment and the lowest in the 20% field capacity. With increasing drought stress, leaf physiological characteristics such as chlorophyll a, total chlorophyll, carotenoid, and proline increased. The investigation into the effect of nano-zinc oxide on the growth characteristics and physiology of saltbush seedlings revealed that this nanoparticle significantly affected only chlorophyll a, total chlorophyll, and proline. The highest amount was observed in the control seedlings, and the lowest was in the nano-zinc oxide treatment with a concentration of 1000 mg/liter. Conclusion: In general, due to the very insignificant effects of zinc oxide nanoparticles observed in this research, their use to increase the resistance of saltbush to drought stress is not recommended. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Grass species have a range of strategies to tolerate soil water restriction, which are linked to the environmental conditions at their site of origin. Climate change enhances the relevance of the functional role of anatomical attributes and their contribution as water stress tolerance factors. Morpho-anatomical traits and adjustments that contribute to drought resistance in Lolium perenne L. (Lp) and Bromus valdivianus Phil. (Bv), a temperate humid grass species, were analysed. The structure of the leaves and pseudostems (stems only in Lp) grown at 20–25% field capacity (FC) (water restriction) and 80–85% FC (control) were evaluated by making paraffin sections. In both species, water restriction reduced the thickness of the leaves and pseudostems, along with the size of the vasculature. Bv had long and dense leaf hairs, small and numerous stomata, and other significant adaptive traits under water stress, including thicker pseudostems (p ≤ 0.001), a greatly thickened bundle sheath wall (p ≤ 0.001) in the pseudostem to ensure water flow, and a thickened cuticle covering on leaf surfaces (p ≤ 0.01) to avoid water loss. Lp vascular bundles developed throughout the stem, and under water restriction the xylem vessel walls were strengthened and lignified. Lp leaves had individual traits of a ribbed/corrugated-shaped upper surface, and the stomata were positioned to maintain relative humidity outside the leaf surface. Water restriction significantly changed the bulliform cell depth in Lp (p ≤ 0.05) that contributed to water loss reduction via the curling leaf blade. This study demonstrated that the two grass species, through different morphological traits, were able to adjust their individual tissues and cells in aboveground parts to reach similar physiological functions to reduce water loss with increased water restriction. These attributes explain how both species enhance persistence and resilience under soil water restriction. [ABSTRACT FROM AUTHOR]

Introduction: Guar (Cyamopsis tetragonoloba) is an annual plant from the legume family and tolerant to salinity and drought, which can be used as an alternative product in low water plains. Ascorbic acid is one of the antioxidants involved in the defense mechanisms of plants against various stresses, including drought, which plays a role in ROS detoxification. Calcium is also an essential element for plant growth, which, despite being immobile, has many electrochemical, structural and catalytic functions in plants. It has been reported that calcium ions can increase drought tolerance in plants by participating in the drought signal transduction process and stimulating abscisic acid synthesis. Therefore, this research was conducted with the aim of investigating the effect of foliar spraying of ascorbic acid and calcium on some morpho-physiological traits of guar under drought stress conditions. Materials and Methods: In order to investigate the morpho-physiological responses of guar to foliar application of ascorbic acid and calcium under drought stress conditions, a factorial experiment was conducted with two factors in the form of a randomized complete block design with three replications in the research greenhouse of Saravan Higher Education Complex in 2020. The experimental treatments included three levels of drought stress (70, 50 and 30% of field capacity) and three levels of foliar application (no foliar application, foliar application with calcium carbonate and ascorbic acid with a concentration of 3‰). Results and Discussion: The results showed that in 50 and 30% of the field capacity, compared to the treatment of 70% of the field capacity, plant height, number of pods per plant, number of seeds per pod, pod length, leaf dry weight and total protein showed a decreasing trend, but traits of reducing sugar, Polyphenol oxidase (PPO) enzyme activity and root length showed an increasing trend. The increase of reducing sugars is considered a mechanism to deal with drought in plants because reducing sugars are osmolytes that play a role in plant cells as regulators of the osmotic potential of the intracellular environment. Similarly, the increase in PPO activity during drought stress is justified by the increase in radical oxygen species generated during this stress, because the increase in the activity of antioxidant compounds as a defense mechanism is essential to maintain cellular processes and prevent the damaging effects of free radicals on plant physiological processes. Foliar application with ascorbic acid did not significantly change plant height and number of pods per plant compared to nonsprayed plants but increased leaf dry weight, total protein, reducing sugar and root length by 22%, 11%, and 21%, respectively. While, calcium foliar application significantly increased plant height, number of pods per plant and leaf dry weight by 16%, 24%, and 42%, respectively compared to nonfoliar application and 8.5%, 12%, and 17.5% compared to foliar application with ascorbic acid, but total protein, reducing sugar, root length and dry weight of root remained statistically unchanged in calcium spraying respect to foliar application with ascorbic acid. However, both ascorbic acid and calcium application than no-foliar application showed a significant increase in the amount of total protein, reducing sugar, root length and dry weight of root and a decrease in PPO enzyme activity. The decrease in PPO activity can be considered as a result of reducing the harmful effects of drought stress caused by the application of calcium and ascorbic acid. Conclusion: In general, it seems that the availability of moisture in less than 70% of the field capacity has caused the formation of mechanisms to deal with drought stress in the guar, but foliar application with ascorbic acid and calcium can somewhat to be effective in modulating the effects of drought stress on this plant. [ABSTRACT FROM AUTHOR]

Soil compaction is a threat to agricultural soil function due to constriction of macro- and meso-pores necessary for air and water movement and crop root elongation. Soils are most vulnerable to compaction when moist. Agricultural soils saturated from winter precipitation or from intentional flooding for groundwater recharge may limit growers’ operational access to fields. The objective of this research was to develop guidance for rain-free “time-to-trafficability” (including shallow workability—when a soil is conducive to both tillage and traffic) after deep wetting, using soil survey data, pedotransfer functions, and a hydroclimatological modeling approach. Trafficability is defined as a threshold of field capacity (θfc) at the soil surface (0–10 cm), ranging from 85% of θfc (clays and silty clays) to 95% of θfc (sands and loamy sands). The θfc threshold is guided by the soil texture plasticity index, an indicator of compaction risk. 2911 soil profiles from soil survey databases were subjected to a wetting simulation, followed by drainage and evaporation using HYDRUS-1D across 11 locations representing mean annual potential evapotranspiration (PET) quantiles from 5% to 95%, four months (January-April), and three different years, assuming no precipitation. Rain-free time-to-trafficability was greatest in fine and loamy soils during cold months (January and February). However, seasonal effects on time-to-trafficability were more pronounced in loamy soils. Non-linear predictive functions were developed for each 0–10 cm textural class to enable mapping the typical time-to-trafficability across PET gradients, revealing clear regional and temporal patterns. Model derived estimates can inform agricultural managed aquifer recharge timing decisions and subsequent risk of soil compaction. Additional research is needed for validation and to better constrain time-to-trafficability estimates for loamy and fine textured soils, which show a greater degree of uncertainty amid greater risk of compaction indicated by plasticity indices.

IntroductionWheat (Triticum aestivum L.) is one of the most important grains used in the world and its production is reduced in different regions due to drought stress. the plant antioxidant system can scavenge the reactive oxygen species (ROS) produced under drought. Induction of mutation using gamma ray is one of the common methods for genetic modification and identification of tolerant and resistant mutants. Mutant T65-58-8 is one of these drought tolerant genotypes that has been obtained by irradiation to Tabasi wheat genotype. The wheat plant needs irrigation during the flowering stage and drought stress is very important in this stage. In this study, in the flowering stage, the enzymes superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) and glutathione peroxidase (GPX) involved in the mechanisms of tolerance to oxidative damage of ROS in the flag leaf were studied and the expression of the genes related to these enzymes was investigated using RNAseq. method.Materials and methodsDrought stress was applied based on field capacity (FC). The experiment was performed as a factorial experiment in a completely randomized design with three replications. Factors studied in this experiment include genotype at two levels (Tabasi parent and Mutant T65-58-8) and drought stress at 5 levels (100% FC or control, 75%, 22%, re-sampling from control pots at 18% FC and sampling after re-irrigation to the pot when had 90% FC). Wheat growth stages can be studied by Zadoks index. SOD activity was measured by Minami and Yoshikawa method, CAT activity by Aebi method, GR activity by Foyer and Halliwell method and GPX activity by Hopkins and Tudhope method. RNA sequencing was performed using Illumina NovaSeq 6000. Gene expression was obtained based on sequencing data by Bowtie2, Tophat2, HTseq-count and Featurecount softwares. After normalization by generating FPKM, Log2FC gene expression was calculated.Results and discussionExamination of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) and glutathione peroxidase (GPX) indices showed a significant difference (p

AbstractGlobally, Rice (Oryza sativa) is one of the most important crops. In India cultivars majorly use wash root type seedlings for rice production. The objective of the study was to assess the influence of transplanting techniques for transplanting wash root paddy seedlings. Two types of mechanical transplanting techniques (two-row hand cranked rice transplanter and tractor operated rice transplanter) were evaluated for three different age of nursery and compared with manual transplanting. The performances for each technique were evaluated in terms of average hill spacing, missing index, multiple index, damage seedlings, floating/buried hills, number of hills/m2, planting efficiency, actual field capacity, field efficiency, energy required and cost of transplanting. Acquired results revealed that the best combination observed was tractor operated rice transplanter and 25 days of seedlings (desirability—0.764). The tractor operated rice transplanter increases the labor productivity by 32.22 times and saved about 66.69% average transplanting cost compared to manual transplanting, whereas it increases the labor productivity by 2.57 times and saved average 35.68% transplanting cost compared to hand crank rice transplanter. Manual transplanting causes non-uniform transplanting, higher missing index and cost of transplanting. Tractor operated rice transplanter at 25 days of seedlings was the best combination for transplanting due its superior techno-economics results.

Combine harvesters' performance during wheat harvests can be analyzed using various methods. These methods typically rely on traditional field-level metrics, such as those defined by ASABE, to address average performances in terms of field or machine. However, next-generation digital agriculture technologies have significantly increased the operation precision of agricultural activities. As a result, the evaluation of instantaneous performance becomes possible. This work introduces a novel methodology that enables fully automated, low-cost, and high-resolution (both in time and space) instantaneous combine performance analyses based on global navigation satellite system (GNSS) positioning records. The methodology incorporates a multi-step, easy-to-follow workflow with customizable modules for efficient and effective data processing. This way, the computation of traditional field capacity metrics can be fully automated even if multiple combines cooperate in harvesting the same field. Furthermore, two groups of novel metrics are proposed: Swath Utilization and Spatial Field Capacity. They enhance traditional metrics by analyzing machine performances both temporally and spatially on a finer scale. As a case study, we computed these metrics for seven fields in Colorado, USA, during wheat harvests across five different years. We compared the results with typical values from ASABE standards to validate the correctness of our data processing methodology. We also provided four analysis examples with a rich set of temporal and spatial visualizations to showcase how our metrics can accurately assess combine performances, quantitatively uncover harvest details, and effectively compare operations in different fields/years for better practice. These new analyses enabled by our methodology are required to harness the full potential of digital agriculture. [ABSTRACT FROM AUTHOR]

The estimation of plant‐available soil water (PASW) is essential to quantify transpiration fluxes, the onset of heatwaves, irrigation water management, land‐use decisions, vegetation ecology, and land surface memory in climate models. PASW is the amount of stored water available for plant use. It is broadly defined as the difference between soil water content at field capacity (FC) and wilting point (WP) in the root zone. The limiting states of FC and WP are linked to gravitational drainage and plant physiology and are often deduced from soil water characteristics at prescribed matric potentials (−3.3 and −150 m for FC and WP, respectively). Evidence suggests that static definition of FC at a constant matric potential ignores dynamic effects on FC attainment affected by soil and climate. Here, we revise the definition of PASW by considering (a) soil‐specific dynamic effects and (b) local climate effects of evaporation and rainfall frequency on PASW. The new global PASW maps benefit from state‐of‐the‐art soil maps, water characteristic parameterization, and incorporation of dynamic definition of FC. For completeness we provide static and dynamic PASW estimates. Globally, ice‐free soils store up to 19,941 km3 of water in the top 1 m (representing 18% of annual terrestrial precipitation). Adjusted for local climatic conditions, global PASW storage rarely exceeds 14,853 km3 per year highlighting the need for multiple refilling of soil profiles. Differences between potential and climatic PASW are manifested primarily in arid regions (where soil profiles are rarely filled to capacity) whereas in humid regions differences in PASW storage are minor. Plain Language Summary: Plant‐available soil water (PASW) is defined as the amount of water held in soil that can be used by plants. It is conventionally estimated as the difference between field capacity (FC) and wilting point (WP), which depend on soil type and plant physiology. Water contents at FC and WP are usually deduced at fixed matric potentials irrespective of soil types (−3.3 and −150 m for FC and WP, respectively). However, FC is affected by various factors such as soil texture, soil structure, and clay type that affect the dynamics of FC attainment and put into question the use of a static definition based on constant matric potentials. Therefore, we used the approach developed by Assouline and Or (2014, https://doi.org/10.1002/2014wr015475) that considers a dynamic definition of FC based on soil‐specific matric potential values beyond which the soil water continuity is substantially reduced or disrupted. The potential PASW was calculated by subtracting the WP from the dynamic FC. The novelty of this study is to incorporate the effect of climate such as evaporative water loss to introduce a climatic PASW. Our results suggest that PASW in arid regions are overestimated when climatic effects are ignored. Key Points: Global maps of field capacity (FC) are compared based on dynamic and static definitionsLocal climate effects of evaporation and rainfall frequency via dynamic FC affect climatic plant‐available soil water (PASW)Incorporating climatic effects mainly reduces PASW in arid regions compared to humid climates [ABSTRACT FROM AUTHOR]

Plant available water storage capacity is a vital soil property for vegetation and soil hydrological processes. Different investigations focused on evaluating the influence of rock fragments on the soil plant water storage capacity usually don't involve the spatial component. This work spatially modelled the available water storage capacity for plants of a tropical Andean micro-watershed as response of some soil properties. Hydrological response units were used for the sampling design and 46 sampling sites were established in which disturbed and undisturbed soil samples were taken. The rock fragments content (2 to 20 mm) in soils were determined by sieving method and the sand and clay content were obtained using Bouyoucos method modified by Day. Undisturbed samples in 98.1 cm3 metal cylinders were taken from the soil to determine the available water retention capacity using the Richards' pressure chamber. For the modelling process, the spatial regression method was used. The results show that the retention of water available for plants is greater on the slopes of the middle and upper part of the studied micro-watershed, and the model created was able to relate the contents of rock fragments, sand, and clay to predict the variable with a good statistical fit. The spatial model developed allowed estimating the values of the plant available water retention capacity with a high degree of assertiveness (r = 0.77). It was established that the gravimetric rock fragments content in the soil surface horizon had a significant influence on the spatial behavior of the plant available water retention capacity. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study introduces a simple and cost-effective method for the indirect determination of field capacity (FC) in soil, a critical parameter for soil hydrology and environmental modeling. The relationships between FC and soil moisture constants, specifically maximum capillary water capacity (MCWC) and retention water capacity (RWC), were established using undisturbed soil core samples analyzed via the pressure plate method and the "filter paper draining method". The aim was to reduce the time and costs associated with traditional FC measurement methods, as well as allowing for the use of legacy databases containing MCWC and RWC values. The results revealed the substantial potential of the "filter paper draining method" as a promising approach for indirect FC determination. FC determined as soil water content at −33 kPa can be effectively approximated by the equation FC33 = 1.0802 RWC − 0.0688 (with RMSE = 0.045 cm3/cm3 and R = 0.953). FC determined as soil water content at −5 or −10 kPa can be effectively approximated by both equations FC5 = 1.0146 MCWC − 0.0163 (with RMSE = 0.027 cm3/cm3 and R = 0.961) and FC10 = 1.0152 MCWC − 0.0275 (with RMSE = 0.033 cm3/cm3 and R = 0.958), respectively. Historical pedotransfer functions by Brežný and Váša relating FC to fine particle size fraction were also evaluated for practical application, and according to the results, they cannot be recommended for use. [ABSTRACT FROM AUTHOR]

Abstract The estimation of plant‐available soil water (PASW) is essential to quantify transpiration fluxes, the onset of heatwaves, irrigation water management, land‐use decisions, vegetation ecology, and land surface memory in climate models. PASW is the amount of stored water available for plant use. It is broadly defined as the difference between soil water content at field capacity (FC) and wilting point (WP) in the root zone. The limiting states of FC and WP are linked to gravitational drainage and plant physiology and are often deduced from soil water characteristics at prescribed matric potentials (−3.3 and −150 m for FC and WP, respectively). Evidence suggests that static definition of FC at a constant matric potential ignores dynamic effects on FC attainment affected by soil and climate. Here, we revise the definition of PASW by considering (a) soil‐specific dynamic effects and (b) local climate effects of evaporation and rainfall frequency on PASW. The new global PASW maps benefit from state‐of‐the‐art soil maps, water characteristic parameterization, and incorporation of dynamic definition of FC. For completeness we provide static and dynamic PASW estimates. Globally, ice‐free soils store up to 19,941 km3 of water in the top 1 m (representing 18% of annual terrestrial precipitation). Adjusted for local climatic conditions, global PASW storage rarely exceeds 14,853 km3 per year highlighting the need for multiple refilling of soil profiles. Differences between potential and climatic PASW are manifested primarily in arid regions (where soil profiles are rarely filled to capacity) whereas in humid regions differences in PASW storage are minor.

Predictions of soil hydraulic properties by pedotransfer functions (PTFs) must be treated with caution when they are used in an application domain which differs from the domain of their original development and calibration. However, in some settings, scientists may have little alternative but to use PTFs calibrated elsewhere. In this paper we consider how legacy data can be used to evaluate PTFs in new regions, paying particular attention to the challenges that arise when, as is often the case, the legacy data are not obtained by independent random sampling, and may be clustered at multiple scales. We undertook this work in southern Africa (Zimbabwe, Zambia and Malawi) where PTFs have been little-used, despite the scarcity of direct measurements of the soil properties of interest. We evaluated the extent to which existing PTFs provide a useful tool for the prediction of soil moisture content at field-capacity (−33 kPa) and permanent wilting-point (−1500 kPa) at different spatial scales. Soil legacy data for Zambia, Zimbabwe and Malawi were collated from various sources and PTFs from temperate and tropical domains were evaluated. We examined error variance components of predictions at within-profile, within-site and between-site scales; and estimated their mean errors. In general the better-performing PTFs (with respect to bias and the size of the error variance components) were ones calibrated with data from a tropical domain. This was most apparent at −1500 kPa. However, not all PTFs calibrated with data on tropical soils performed well, and predictions from some PTFs calibrated over a temperate domain were better at −33 kPa. The observations were spatially clustered, with data from different depth intervals in the same profile, from profiles in the same experimental site or farm, and from clusters across the region. This enabled us to show, with an appropriate mixed model analysis, that PTFs which effectively capture regional-scale variation may be less useful for predicting variation within a profile. We propose that such studies, based on legacy data, and with a suitable linear mixed model, should be used to screen PTFs of any provenance before their wider application.

Drought stress is a major abiotic factor that frequently suppresses crop growth at various stages. The main ambition behind this current work is to check the influence of foliar applied silicon @50 ppm at flag leaf stage on three oat cultivars (IST, S-85/Sl and PARC) under three different field capacities (100% FC, 75% FC and 50% FC). Data about antioxidants enzymes including SOD (Superoxide dismutase), CAT (Catalase), proline compatible solutes and MDA (Malondialdehyde) accumulation was collected at flag leaf stage. Similarly, relative water content (RWC), excised leaf water loss (ELWL), membrane thermo-stability index (MTSI), SPAD chlorophyll and leaf area index (LAI) were determined. The given outcomes proved that silicon helped to minimize the harmful effect of drought by increasing proline (by 43%) as well as SOD (by 46%), CAT (by 52%) and decreasing the MDA (by 61%) in oat-tested cultivars. Moreover, Si application resulted to lowering of MTSI (by 12%) and ELWL (by 12%) while it helped to increase RWC (13%). Furthermore, LAI and chlorophyll (29%) were significantly increased with silicon application. The obtained results showed that silicon treatment could help to augment the harmful effect of water stress and mitigate this stress in different crops. Our research work provided the comprehensive note on physio-chemical properties of all oat cultivars under water stress conditions treated with silicon. This research work clearly showed that silicon could be used to mitigate water stress by maintaining leaf water balance under drought stress condition. [ABSTRACT FROM AUTHOR]

Dry direct seeding (DDS) is a water saving rice cultivation technology. The sowing of dry direct seeded rice in boro season is generally delayed when grown under the T. aman rice - Rabi crops - DDS boro rice pattern. An experiment was conducted at the Agronomy Field of Bangladesh Agricultural University, Mymensingh to study the effect of sowing date and irrigation schedule on growth and yield of DDS boro rice. The experiment used two sets of treatments (a) two sowing dates viz. 22 February and 13 March; and (b) six irrigation regimes viz. no irrigation, one irrigation at 25% Field Capacity (FC), two irrigations at 25% FC and 1 week after (WA) 25% FC, three irrigations at 25% FC, 1WA 25% FC and 2 WA 25% FC, four irrigations at 25% FC, 1 WA 25% FC, 2 WA 25% FC and 3 WA 25% FC and one irrigation at 3 weeks after 25% FC and the treatments were arranged in a split-plot design with three replications allocating sowing dates into the main plot and irrigation schedule into the subplots. BRRI dhan58 was used as test crop. The result showed that grain yield of the crop did not differ significantly for sowing on 13 March and 22 February. The study revealed that BRRI dhan58 sown on 13 March with four irrigations applied at 25% FC, 1 WA 25% FC, 2 WA 25% FC and 3 WA 25% FC produced the highest economic return and hence it is concluded that the sowing date of boro rice could be delayed up to 13 March with four irrigations. [ABSTRACT FROM AUTHOR]

Local genetic resources could constitute a promising solution to overcome drought stress. Thus, eight (8) durum wheat landraces and one improved variety were assessed for drought tolerance in pots under controlled conditions. Three water treatments were tested: control (100 % of the field capacity (FC)), medium (50 % FC) and severe (25 % FC) stress. The assessment was carried out at the seedling stage to mimic stress during crop set-up. Results showed that increased water stress led to a decrease in biomass and morpho-physiological parameters and an increase in antioxidant enzyme activities. Severe water stress decreased the chlorophyll fluorescence parameters, relative water content (RWC) and water potential of the investigated genotypes by 56.45, 20.58, 50.18 and 139.4 %, respectively. Besides, the phenolic compounds content increased by 169.2 % compared to the control. Catalase and guaiacol peroxidase activities increased 17 days after treatment for most genotypes except Karim and Hmira. A principal component analysis showed that the most contributed drought tolerance traits were chlorophyll fluorescence parameters, RWC and electrolyte conductivity. Unweighted pair group method with arithmetic mean clustering showed that the landraces Aouija, Biskri and Hedhba exhibited a higher adaptive response to drought stress treatments, indicating that water stress-adaptive traits are included in Tunisian landraces germplasm. [ABSTRACT FROM AUTHOR]

Copyright of Scientific Journal of Agricultural Sciences (SJAS) is the property of Beni Suef University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purslane (Portulaca oleracea L.) is an edible wild plant that is widely grown in the world, including Türkiye. Purslane plant, which is an important component of Mediterranean cuisine, can grow spontaneously in nature. Stress conditions can directly or indirectly affect its growth and development in the environment in which it is grown. In the current study, stress conditions of soil organic matter content, irrigation water amount and irrigation water salinity were investigated in pot experiments. The experiments were carried out in a 72 m2 greenhouse established on the Dokuz Eylül University Tınaztepe Campus. From the variables, soil organic matter was applied as 1%, 1.8% (control), 3% and 5% on a dry weight basis. 15 purslane seeds were planted in each pot and left to germinate. Irrigation water amounts were chosen as 100%, 75%, 50%, 30%, 15% of the field capacity. The last variable in the application was determined as the salinity of the irrigation water; the conductivity of the applied irrigation waters were control (tap water-about 0.5 mS/cm), 4 mS/cm, 8 mS/cm, 16 mS/cm. All pots were prepared in four repetitions and the study was carried out with a total of 320 pots. Experiments were carried out for 90 days from the first planting. In the study, it was observed that the increase in organic matter increased plant germination. Statistical evaluation was also made and the effects of irrigation water amount and salinity were also evaluated according to principal component analysis. As the field capacity decreased, decreases were observed in plant growth, but this was mostly observed at 30% and 15% field capacity. The negative effects of salinity on plant growth were observed at 8 mS/cm and 16 mS/cm values.