Irrigation Water Use Research Articles

Assessment and forecast of water resources use in Uzbekistan

The article examines the assessment of the state and problems of irrigation water use in the republic in the past and in the near future. A comparative analysis of the state of water resources use for the period of the last 30 years from 1989 to 2019 was carried out. According to the estimates, own water withdrawal for 5 years (2014 / 15-2018/19) shows that an average of 53.2 billion m3 were used for irrigation, including 50.5 billion m3 from rivers. At present (2018-2019), an average of 57.06 billion m3 of water is taken for irrigation of 4.289 million hectares of land, against 63.02 billion m3 approved in 1989. At the same time, the actual water consumption amounted to 48.9 billion m3. Specific water consumption (in the years of average water content) in the Amudarya river basin is 12.5 thousand m3/ha, in the Syrdarya basin - 10.4 thousand m3/ha. Forecast calculations show that there is a tendency to reduce water from rivers to agriculture by an average of 0.104 billion m3/year, with an increase in other sectors from 11.53% (communal and household sector) to 100% (fisheries). The volume of discharges into CDS is decreasing due to the use of collector-drainage waters throughout the region, while specific water consumption has increased to 11.50 thousand m3/ha, i.e. by 450 m3/ha or 28.1%. The reasons for the lack of water for irrigating agricultural crops during the period of vegetative irrigation are stated. The issues of water saving and ways of transition to modern technologies for the use of surface and ground waters, redistribution of water and solutions for the interstate use of river resources are touched upon.

Effect of Rural Sewage Irrigation Regime on Water-Nitrogen Utilization and Crop Growth of Paddy Rice in Southern China

Reclaimed water irrigation has become an effective mean to alleviate the contradiction between water availability and its consumption worldwide. In this study, three types of irrigation water sources (rural sewage’s primary treated water R1 and secondary treated water R2, and river water R3) meeting the requirements of water quality for farmland irrigation were selected, and three types of irrigation water levels (low water level W1 of 0–80 mm, medium water level W2 of 0–100 mm, and high water level W3 of 0–150 mm) were adopted to carry out research on the influence mechanismS of different irrigation water sources and water levels on water and nitrogen use and crop growth in paddy field. The water quantity indicators (irrigation times and irrigation volume), soil ammonium nitrogen (NH4+-N) and nitrate nitrogen (NO3−-N), rice yield indicators (thousand-grain weight, the number of grains per spike, and the number of effective spikes), and quality indicators (the amount of protein, amylose, vitamin C, nitrate and nitrite content) of rice were measured. The results showed that, the average irrigation volume under W3 was 2.4 and 1.9 times of that under W1 and W2, respectively. Compared with R3, the peak consumption of rice was lagged behind under R1 and R2, and the nitrogen form in 0–40 cm soil layers under rural sewage irrigation was mainly NH4+-N. The changes of NO3−-N and NH4+-N in the 0–40 cm soil layer showed the trend of declining and then increasing. The water level control only had a significant effect on the change of NO3−-N in the 60–80 cm soil layer. Both irrigation water use efficiency and crop water use efficiency were gradually reduced with the increase of field water level control. The nitrogen utilization efficiency under rural sewage irrigation was significantly higher than that under R3. Compared with the R3, rural sewage irrigation could significantly increase the yield of rice, and as the field water level rose, the effect of yield promotion was more obvious. It was noteworthy that the grain of rice under R1 monitored the low nitrate and nitrite content, but no nitrate and nitrite was discovered under R2 and R3. Therefore, reasonable rural sewage irrigation (R2) and medium water level (W2) were beneficial to improve nitrogen utilization efficiency, crop yield and crop quality promotion.

Water Delivery Performance of Canal Irrigation: A Case Study of Chalakudy River Diversion Scheme

The role of irrigation is important in mitigating the challenges involved in food production under the changing climate scenarios. Adequacy and equity in water distribution are the primary concern regarding the performance of any irrigation scheme. Conveyance efficiency and two adequacy indicators, namely, Relative Water Supply and Adequacy were used to evaluate the performance of Chalakudy River Diversion Scheme (CRDS) located in central Kerala, India, in the present study, Water withdrawal data collected from Irrigation Department, and data collected from field measurements of canal discharge and seepage loss were used in the study. Irrigation requirement of the canal command area was worked out using the FAO’s CROPWAT 8.0 software. The results revealed that the average annual irrigation demand of the CRDS command area is 46.90 Mm3. Measured flow rate through the canal system showed that the flow decreases towards the tail end. Loss of water through seepage from the canal was high in the irrigation scheme due to the highly damaged condition of canal lining and poor maintenance. The CRDS canal system’s overall conveyance efficiency was found to be 51%. Based on Relative Water Supply and Adequacy Indicator, functioning of the irrigation scheme falls in the category of ‘fair’. Apart from proper repair and maintenance of canal system, conjunctive use of groundwater and canal water for irrigation is suggested towards the tail reaches to alleviate irrigation water inadequacy problems in the CRDS command area.

Structural And Functional Relationship Study In Plant Salinity Stress

In today’s world the increased use of low-quality water for irrigation and soil salinization, saltness is a huge biotic problem that effecting factory growth and product in numerous corridors in the world. In repercussion to salt stress, plant cells accumulate compatible solutes and redistribute ions, all of which contribute them to acclimate to a low soil water potential. In addition, the endogenous abscisic acid (ABA) content increases daily, followed by changes in principle genetic expression in salt stress conditions. Here we are going to discuss about the proteins involved in plant salinity stress and their interactions with the salt tolerant factor which has a negative impact with the plant growth system. Some highly evaluated proteins that were observed under this stress are Plant ferredoxin-like protein (PFLP), Arabidopsis thaliana Salt Tolerance Related Protein (STRP), OsEXPA7, ribulose-1, 5-bisphosphate carboxylase (RuBP), etc. This report is also going to focus on various transcription factors (tf), responsible for the enhanced tolerance under biological activity of plant development. TFs bZIP, MYBs, bHLH, C2H2-Dof, G2-like, AP2-EREBP, NAC, GATA, ARF, ERF, bZIP and MYB which were highly up- regulated in salt stress response.

Efficiency of use of magnetic water in drip irrigation of cotton

The article presents the results of field research conducted on a cotton field of drip irrigation using magnetic irrigation water. The research aimed to study the effect of magnetic water on the growth, development, and increase in cotton yield in the meadow-serozem soil-reclamation conditions of the Chirchik-Akhangaran valley. The authors provide an overview of the designs and the principle of operation of various magnetic devices used for irrigation in domestic and world practice. In order to save irrigation water and study the effect on the growth, development, and increase in cotton yield, field studies were carried out using magnetized water during drip irrigation of cotton.

Establishment of additional norms for irrigation water

Due to the scarcity of water resources, there is a need for an additional source of irrigation. Drainage waters can serve as such sources. To use these waters, it is necessary to develop a number of measures. The aim of the study is to reduce the negative consequences by increasing the norms of preventive irrigation. It is vital to fulfilling the tasks set: calculation of additional water supply rates and irrigation regime when designing the use of drainage water for irrigation. As a result of field studies and according to the methodology of classifications developed by the Central Asian Research Institute of Irrigation (SANIIRI) analysis of the suitability for irrigation of pumped water from vertical drainage wells in the areas of the Fergana region. Studies conducted by scientists in Central Asia have shown that one of the methods to prevent soil salinization in the intra-contour use of collector-drainage water is the requirements with the following conditions: the ratio of total water supply to total evaporation and the ratio of drainage flow to the water supply. Taking into account the established coefficient, the irrigation rate must be increased depending on the mineralization of water and the mechanical composition of the soil.

Influência do sistema consorciado e monocultivo na cultura de fava sob estresse salino

ABSTRACT The fava bean crop makes an important socioeconomic contribution to the Northeast region of Brazil. However, in this region, there is a quantitative and qualitative shortage of water, being necessary the use of brackish water for irrigation. This study aimed to evaluate the saline stress on the yield and water-use efficiency in fava bean crop cultivated under monoculture and intercropping systems. The experiment was conducted under field conditions, using a randomized blocks experimental design, in a 5 × 2 factorial arrangement, with four replications. The first factor corresponded to five levels of electrical conductivity of irrigation water (1.0, 2.0, 3.0, 4.0 and 5.0 dS m−1) and the second comprised two cropping systems: fava bean grown in monoculture and intercropped with corn. The salt stress negatively affected the number of pods in the intercropped system, but with less intensity. The increase of salts in the irrigation water reduces the pod length, diameter and mass, as well as the yield and water-use efficiency, while the monoculture system is less affected by these effects.

ДИНАМИКА ИРРИГАЦИОННОГО КАЧЕСТВА ОРОСИТЕЛЬНОЙ И ДРЕНАЖНО-СБРОСНЫХ ВОД НИЖНЕ-ДОНСКОЙ ОРОСИТЕЛЬНОЙ СИСТЕМЫ В 1972 И 2019–2021 ГОДАХ

Purpose: to assess the dynamics of the irrigation quality of irrigation water from the main canal and drainage wastewater (DWW) from the outlet collectors using the example of the Nizhne-Don irrigation system (NDIS) to justify the sustainability of their environmental safety. Materials and methods. The objects of the study were DWW from the TsS, K-3, LS-2 and MKL-7 collectors, water from the Tsimlyansk reservoir supplied to the Nizhne-Don main canal (NDMC). The subject of the study was the hydrochemical indicators of the DWW in 1972 and 2019–2021, and the comparative irrigation characteristics of the waters. Results. Comparison of water irrigation characteristics from NDMC in 1972 and 2019 showed an increase in sulfate salinity by about 35 %. The irrigation coefficient according to H. Stebler (Ka) has decreased from 43.24 to 28.15 since 1972, while the irrigation water quality from NDMC remains good (Ka > 18). In 1972, the average value of the irrigation coefficient (Ka) of DWW during the irrigation period in the K-3 collector was 2.98, in LS-2 – 4.14, in TsS – 5.54, in MKL-7 – 22.96. In 2019–2021 – 10.44; 14.85; 12.62; 11.61 respectively. Conclusions. The irrigation quality of the Don irrigation water from the NDMC has now deteriorated compared to 1972 by 1.54 times. Over the fifty-year period of operation of the NDIS, the irrigation quality of the DWW in the collectors K-3, LS-2 and TsS increased by 2–3.5 times. Irrigation water quality in the MKL-7 collector decreased by 2 times. It has been proven that the use of fresh irrigation water for irrigation contributes to a sustainable increase in the environmental safety of DWW. The need to reuse DWW for irrigation should be decided at the regional level based on the economic feasibility of the cost of cleaning and transporting water to the irrigation system.

Drip Irrigation and Compost Applications Improved the Growth, Productivity, and Water Use Efficiency of Some Varieties of Bread Wheat

In hyper-arid and arid zones, management of crop water requirements is considered a vital component for sustaining crop production. The efficiency of the irrigation method and the application of many kinds of organic matter are practices that should be followed in Egypt to maximize the use of irrigation water. Two field experiments were conducted during the two successive winter seasons of 2020/2021 and 2021/2022 to study the effect of drip irrigation systems and of several types of compost on yield and yield attributes of four cultivars of wheat in newly reclaimed sandy soils. Studied factors were irrigation levels based on the amount of water evapotranspiration (ET) (I1, I2, I3) and the application of compost types (Com1, Com2 and Com3) on four bread wheat cultivars. The parameters measured at each irrigation level were: heading date (day), plant height (cm2), number of spikes/m2, number of grains/spike, 1000-grain weight (g), grain yield (t/fed.), Biological yield (kg/fed.) and harvest index (%). The farmyard manure (Com3) gave the maximum values under irrigation shortages, reflected in producing the maximum values for traits measured in the 2020/2021 season as compared to (Com1) or (Com2) applications, which scored lower values for the traits for the different cultivars for wheat. The interaction (I1, I2) × Com3 × (Mis1, Mis2) led to a significant increase during both seasons for all the yield and yield components studied. A drip irrigation system at the level of 80% of ET and application of Com3 is recommended to optimize wheat productivity from the unit area. The savings in water irrigation would allow expansion of the cultivated area to decrease the gap between local crop production and local requirements.

Impact of wild solanaceae rootstocks on morphological and physiological response, yield, and fruit quality of tomato (Solanum lycopersicum L.) grown under deficit irrigation conditions

It has been established that climate change has a direct impact on water availability, an essential resource for agricultural development. As a result, controlling, mitigating, and adapting to water deficit requires the advancement of research on promising wild flora species. As recent studies have shown, wild relatives of certain cultivars are tolerant to adverse factors, enabling the development of sustainable and resilient agriculture. The present study evaluated the morpho-physiology and productivity of tomato scions grafted on wild Solanaceae (Datura stramonium, Solanum sisymbriifolium, Solanum quitoense, and Cyphomandra betacea) grown under water deficit conditions (100% ETc - high level, 75% ETc - moderate level, 50% ETc - medium level, and 25% ETc - low level). The results showed that tomato plants grafted on Datura stramonium rootstocks performed better morpho-physiologically under deficit irrigation. The improved osmoregulation caused by a higher relative water content (98.49%) allowed the scion to be more tolerant to water stress. In addition, these scions showed high water potential during their phenological stages (vegetative −0.47 MPa, flowering −0.59 MPa, and production −0.64 MPa), as well as improved photosynthetic efficiency. The overall tolerance of the scion resulted in better yield (8.14 kg/plant) with higher number of commercially valuable fruits. The D. stramonium rootstock allowed better management and use of irrigation water, increasing productivity (54.95 kg/m3); that is, it is presented as a species with potential for establishing tomato production areas in scenarios of water scarcity or cultivation under deficit irrigation.

Power of Millets- Critical for addressing Ecological, Agrarian, and Emerging health crisis in Punjab

The state of Punjab is facing a major threat of ecological, agrarian as well as emerging health crisis. Continuously depleting water tables due to unregulated use of irrigation water and increased cultivation of water-thirsty, varieties of rice are posing major threat to water availability in the state. Indiscriminate use of chemicals in farming leading to soil infertility, polluted surface waters and air pollution are contributing to ecological catastrophe and eventually leading to many health problems in the population. Hence there is need to focus on environmentally friendly, economically viable and health benefitting solutions. Millets as climate change compliant crops score highly over other grains in terms of marginal growing conditions and high nutritional value are proposed as a solution for emerging challenges in Punjab.

Economic Analysis and Determination of Irrigation Water Use Efficiency in Second Crop Silage Corn Varieties

Çalışmada ikinci ürün olarak yetiştirilen farklı FAO olum gruplarına sahip 8 adet silajlık mısır çeşidinin (ADA-523, AGA, Keravnos, Simpatico, Kilowatt, P9027, SY-Gladius, DKC6308) silaj verimi, net gelir, sulama suyu kullanım etkinliği (IWUE) ve birim su hacmine göre net gelir değerleri belirlenmiştir. Bilecik ekolojik koşullarında 2021 yılında yürütülen çalışma Tesadüf Blokları Deneme Desenine göre 3 tekrarlı yürütülmüştür. Vejatasyon dönemi boyunca sulama suyu miktarları geçci çeşitlerde 340.34 mm, erkenci çeşitlerde ise 294.05 mm olarak gerçekleşmiştir. En yüksek silaj verimi ve net gelir FAO olum grubu göre geççi olan DKC6308’den sırasıyla 73.60 t ha-1 ve 24597.6 TL ha-1 olarak elde edilmesine rağmen, en yüksek sulama suyu kullanım etkinliği ve birim su hacmine göre net gelir ise FAO olum grubu erkenci çeşit olan P9027’den sırasıyla 24.15 kg m-3 ve 7.88 TL m-3 olarak elde edilmiştir. Sonuç olarak Bilecik ekolojik koşullarında verim ve net gelir açısından DKC6308 silajlık mısır çeşidi ön plana çıkmıştır.

Design and Performance Evaluation of a Low-Cost Domestic Level Filter to Treat Kitchen Wastewater

The aspects of water security mainly govern by the availability and the quality of the water. As foreseen, use of portable fresh water for landscape irrigation can be a problem in the future. This research study was carried out with objectives of characterizing the raw kitchen wastewater (KWW), designing a domestic level filter for treating KWW and evaluating the removal efficiency of newly designed filter for reuse purpose. Four combinations of treatment systems were used namely in an order, sand and gravel layer, sand and bricks, sand and bricks with a coco peat layer and sand, bricks, coco peat and activated charcoal units for filtering. Raw kitchen wastewater samples were collected three times per day and made a composite sample by mixing equal proportion of each. Water quality parameters were measured before and after treatment of the KWW and compared with the Central Environmental Authority, Sri Lanka (CEA) standards. The average pH, Chemical Oxygen Demand (COD) and oil content in raw KWW was significantly higher than CEA standards. Based on results, raw KWW cannot be reuse for irrigation and it requires adequate treatment prior irrigation. The quality of filtrate from treatment system four resulted with the mean values of pH, electrical conductivity, temperature, total dissolved solids, COD and oil content and respectively quantitative figures were 7.2 ,0.65 mS cm-1, 29.5°C, 230.1 mg L-1, 365 mg L-1 and 2.8 g L-1 .The combination of sand, bricks, coco peat and activated charcoal filter filtrated effluent was within the CEA standards, which can be reuse for irrigation.

DIRECT SOWING IMPROVES CHLOROPHYLL CONTENT OF SILAGE MAIZE FULLY IRRIGATED WITH RECYCLED WASTE WATER BY INCREASING WATER RETENTION IN THE SOIL

Increasing fresh water shortage has revealed the use of waste water in agricultural irrigation, deficit irrigation approaches and integrated management of soil moisture with tillage-sowing practices. The crop productivity in the irrigated conditions is directly controlled by photosynthetic activities. Therefore, the effects of the irrigation with recycled domestic waste water at different irrigation water levels (100%, 67% and 33%), compared to full irrigated fresh water, on the chlorophyll content of silage maize and surface soil moisture in conventional tillage and direct sowing conditions were examined in the irrigation periods of two experimental years (2020 and 2021). The soil moisture was determined by 1.5% higher in direct sowing than in conventional tillage, and the chlorophyll content in full irrigation with waste water and the direct sowing was found by 4.9% and 1.9% higher than in full irrigation with fresh water and conventional tillage, respectively. However, chlorophyll content decreased by 20.7% and 34.0% at 33% and 67% deficit irrigation with waste water compared to full irrigation with waste water. The significant (p<0.01) linear correlation between the soil moisture and chlorophyll content showed that chlorophyll content can be managed with the soil moisture. It can have concluded that full irrigation with waste water in the direct sowing can be recommended with positive effects on the conservation of fresh water resources, effective managing soil moisture, thus saving irrigation water, increasing chlorophyll content and crop productivity.

Dynamics System Model for the Optimization of Irrigation Water Allocation

This paper intends to build the optimization of irrigation water allocation. The research method uses a dynamics system that the methodology consists of building the causal loop diagram that amplifies (positive feedback loop) or negates (negative feedback loop) for a change in a system variable. Water balance is an important aspect of using the water resources. Its existence can provide an overview of the balance sheet conditions between water availability and water needs over a specific period. The water balance sheet can show the status of water availability conditions, whether the status is already in deficit or still excessive. Irrigation as part of water resource management is a system in society that is dynamic and depends on the environmental conditions, mainly because of the variety of actors, the variety of uses, across the different administrative areas and different cultures. This condition is further aggravated by the reduction in water sources that can be used as the main source of irrigation due to climate change, changes in land use and other uses such as domestic needs. Therefore, the complexity and limitations of the water resource are a challenge for irrigation development now and in the future. This research intends to optimize the irrigation water allocation by suing the dynamics system. By analyzing the causal relationships that affect the water availability, causal relationships that affect water demand, and formulating interventions with high leverage, the optimal condition is found. The results show that the limited amount of water availability with the increasing number of waters needs for various uses requires arranging the optimal water allocation in a fair, efficient and environmentally sound sense. However, the use of water for irrigation that can be allocated to fisheries will obtain maximum economic benefits if fisheries get top priority in water allocation.

30 años no es nada: una aproximación a las políticas ambientales en Uruguay

Three decades have elapsed since the creation of an explicit environmental policy in Uruguay. The issue was assigned ministerial rank in a State Secretariat with shared powers in 1990, in the run-up to the Earth Summit in Rio de Janeiro. In 2020, a Ministry of the Environment was created, with the reassignment of some of the powers of previously existing ministerial departments. In the same period, the country has materialized a productivism vocation, based on the promotion of agriculture and forestry. This article compiles some of the environmental policies -in particular environmental impact and nature protection- describing the main characteristics of the current environmental institutional context and its relationship with productive policies, both in a specific region (east of the country) and in a specific activity sector (agricultural irrigation). The recent legislative debate during the amendments to the legal framework for the use of water for irrigation, extending the water frontier by means of the financialization of the activity, is analyzed. The final discussions return to the relationship between public policies, environment and agricultural production from a sustainable intensification insight.

Representing Indian Agricultural Practices and Paddy Cultivation in the Variable Infiltration Capacity Model

AbstractIncreased irrigation due to agricultural intensification has profound impacts on the surface water and energy balance at regional to local scales. Recent updates of the state‐of‐the‐art Land Surface Models (LSMs) include the impacts of irrigation on surface hydrology. The Indo‐Gangetic Plain (IGP) is one of the global hotspots of irrigation water applications. However, the direct application of these models to Indian basins has certain limitations. The commonly employed flood irrigation technique is often indiscriminate and unmanaged, unlike the state‐of‐the‐art models' estimation of crop water use based on soil moisture (SM) conditions. The primary crop in the IGP is paddy, cultivated in inundated fields with quite distinct water and energy partitioning mechanisms represented in very few models. Here, we developed an improved irrigation module to simulate the Indian agricultural practices for the widely used Variable Infiltration Capacity model. We incorporated the crop‐specific water use for flood irrigation, calculated based on previously reported field studies. The water and energy balance processes are modified by incorporating the ponded paddy fields with proper parameterization. We achieved moderate improvement in the simulated evapotranspiration (ET) and SM of the IGP, particularly in the non‐monsoon seasons with the updated model. We found that ET and SM are more sensitive to the irrigation techniques than the interval of irrigation application. Runoff strongly responded to irrigation technique as well as the interval of application. We emphasize accurate representation of irrigation practices in the LSMs, specifically when applied to the human‐natural hydrological system.

Row spacing and irrigation management affect soybean yield, water use efficiency and economics

Declining water levels in the Mississippi River Valley Alluvial Aquifer necessitates research on the management practices that can reduce irrigation water use and improve irrigation water use efficiency. A three-year field study from 2019 to 2021 evaluated the effects of row spacing and irrigation management on soybean seed yield and quality, irrigation water use efficiency (IWUE), water productivity (WP), and profitability. Soybean was planted in two row spacings [single- (SR) and twin-row (TR)] and irrigated with three different methods [every row irrigated (ERI), alternate row irrigated (ARI), non-irrigated (NI)]. Soybean yields were increased with application of irrigation either as ERI or ARI as compared to NI in all three years ranging from 20% to 79%. The ERI had 20% increase in yield over ARI in 2021, whereas no significant differences were found between ERI and ARI in 2019 and 2020. Averaged over row spacing, IWUE was 66–91% greater with ARI compared to ERI. Only 2021 showed an increase (34%) in WP with irrigation applied as ARI than NI. Differences in rainfall amount among years and amount of irrigation applied under different treatments affected the soybean yields. Soybean yield showed reduction by 0.37–1.2 kg ha−1 with each unit increase in cumulative stress (kPa-days) for soil moisture potential drier than the −40 kPa on very fine sandy loam soils. Twin-row soybean had higher expected returns in all cases except for the NI and ERI in 2021. The TR soybean produced the greatest average risk-return than other treatments. The ARI with TR had the second highest overall risk-return trade-off. The ARI resulted in an equivalent risk-return production system as ERI for SR soybeans. Alterations in furrow irrigation methods could be more beneficial than row spacing to improve soybean productivity and IWUE.

Comprehensive Selection Criteria for Some Barley Genotypes under Different Water Stress Treatments

Nowadays, water scarcity is a great danger to agriculture development, in semiarid and arid regions beside climate change risks. Egypt is suffering from scarce water resources for agriculture; it is of high priority to rationalize irrigation water use. During two seasons, 2019/2020 and 2020/2021 the experimental were carried out to investigate the effect of three different irrigation water treatments (I1 at 45, I2 at 60 and I3 at 75% depletion of available soil moisture) on some photosynthetic, agronomical, grain quality parameters, water productivity for eight barley genotypes. Also, classify them on the SSR molecular level. The results showed that there were high genetic variations found among the eight genotypes with significant responses to irrigation water treatments. Rationalize irrigation water from I1 to I3 had a negative effect on all studied phenotypic traits, whereas had an appositive effect on leaf diffusive resistance and cured protein content and inducement all genotypes to flower early by average increasing (27.7, 12.7 and 7.08%) respectively. Giza 138, Giza 131, and Line 4 gave high mean performance values of the measured characters besides, attaining high WP values were 1.14, 1.08, and 0.89 kg grain/m3 applied water I1, I2, and I3 irrigation treatments, respectively. While, WUE values increased with increasing water availability. Water use efficiency values were 1.92, 1.71, and 1.34 kg grain/m3 consumed water for I1, I2, and I3 irrigation treatments, respectively. Twenty-six alleles were generated using ten SSR primers with a mean value of 2.6 alleles per locus. The Polymorphism Information Content (PIC) value of each SSRs marker ranged from 0.33 (Bmag 0387) to 0.47 (Bmac 0167) with an average value of 0.34. Cluster analysis clustered the eight barley genotypes into two major clusters divided according to their response to water stress tolerance. The genetic information about eight barley genotypes for water stress tolerance was established, for use them in breeding programs in Egypt.

Moderate soil drying improves physiological performances and kernel yield of maize

AbstractWater shortage is a serious problem in crop production, and maize (Zea mays L.) is the largest grain crop worldwide. It would have great significance in increasing kernel yield and water use efficiency to establish a high‐yielding and water‐saving irrigation technology in maize. In this study, two high‐yielding maize varieties were used and two irrigation regimes composed of well‐watered (WW) and moderate soil drying (MD) were conducted. Physiological performances, kernel yield, and water use efficiency were investigated. Compared with WW, the MD increased kernel yield by 4.69–6.40%, reduced irrigation water by 26.5–33.3%, and improved irrigation water use efficiency by 43.1–59.3%. In terms of physiological performances, the MD enhanced the leaf superoxide dismutase (SOD) activity, decreased malondialdehyde (MDA) content, increased the leaf photosynthetic rate and the contents of indole‐3‐acetic acid (IAA), zeatin (Z) + zeatin riboside (ZR), gibberellin‐3 (GA3), and abscisic acid (ABA) in inferior kernels, promoted the remobilization of non‐structural carbohydrates (NSC) from stalks and sheaths to kernels, and improved the filling rate and weight of inferior kernels. Correlation analysis showed that IAA, Z + ZR, and ABA contents in kernels were significantly and positively correlated with the kernel filling rate. These results suggest that the moderate soil drying imposed during the whole growth period of maize can achieve the dual goal of increasing food production and saving water by improving physiological performance, especially regulating hormonal levels in the kernel.