Irrigation Methods Research Articles

Wick irrigation improves seed yield and water use efficiency in mung bean

AbstractDrought is a serious threat to crop growth, and finding new irrigation methods can save water. This study was conducted to investigate water use efficiency and seed yield in mung bean under wick irrigation. Irrigation treatments consisted of the wick irrigation method, surface irrigation (common irrigation) with water equivalent to wick irrigation, and surface irrigation with the double water use of wick irrigation. The results showed that the wick irrigation had a seed weight per plant, 100‐seed weight, seed number per pod, pod number per plant, seed yield, biological yield, water use efficiency of seed, water use efficiency of biomass and net income increase of 164, 14, 28, 80, 164, 128, 164, 128 and 300%, respectively, compared to surface irrigation with an equivalent water volume of wick irrigation. Wick irrigation resulted in increases in plant height, internode length, leaf number per plant, node number per plant, branch number per plant, leaf length and leaf width of 60, 59, 65, 91, 91, 52 and 52%, respectively, compared to surface irrigation with an equivalent water volume of wick irrigation. In conclusion, the wick irrigation method, as a new method, can save water and improve seed yield and net income.

Assessing the feasibility of sprinkler irrigation schemes and their adaptation to future climate change in groundwater over-exploitation regions

Promoting appropriate water-saving irrigation is an important pathway to alleviate groundwater overexploitation in irrigated agriculture. Whether an alternative irrigation method is feasible relies on quantitative assessments of its impacts on crop yield and hydrological cycle, especially in the groundwater overdraft area that faces a dilemma between water scarcity and food security. Using a groundwater-module-improved SWAT (Soil & Water Assessment Tool) model, five GCMs (General Circulation Models) projections of CMIP6 (Coupled Model Intercomparison Project 6), and a linear programming algorithm, sprinkler irrigation was simulated, evaluated, and optimized in a representative global groundwater mining location, the piedmont plain of the North China Plain. During the historical period (1993–2012), the results showed that, in general, sprinkler irrigation had advantages in benefiting crop transpiration of winter wheat and reducing percolation, hence improving water use efficiency with reference to traditional surface irrigation. Specifically, compared to traditional surface irrigation schemes, winter wheat yields increased by 12%− 14% with a 225 mm irrigation quota; they were stable with a 150 mm irrigation quota; but they decreased by 4% with a 75 mm irrigation quota. The shallow groundwater tables would decline at an average rate of 1.29 m/yr, 0.83 m/yr, and 0.35 m/yr, respectively, under sprinkler irrigation with 225 mm, 150 mm, and 75 mm irrigation quotas. Future climate changes (increased precipitation, air temperatures, and CO2 concentration) would bring effects of improving wheat yield by 6%− 7% and increasing groundwater vertical recharge by 58%− 122% in 2030–2049. The variations of predicted future shallow groundwater tables were − 0.37 m/yr, 0.01 m/yr, and 0.40 m/yr with the 225 mm, 150 mm, and 75 mm irrigation quotas, respectively, in the SSP2–4.5 scenario; and the corresponding results were − 0.45 m/yr, − 0.05 m/yr, and 0.34 m/yr in the SSP5–8.5 scenario. The optimization results showed that sprinkler irrigation could be implemented in approximately 50% of the study area to achieve shallow groundwater equilibrium and stable wheat production simultaneously in the near future. And the dominant sprinkler irrigation schedule after optimization was found to be scheme S3 (irrigation frequency for wheat was 5 times) with a limited irrigation quota of 150 mm. This study provides detailed data for planning sprinkler water-saving irrigation regimes and groundwater pumping strategies in China’s breadbasket, as well as a reference for global irrigated agriculture with over-drafted aquifers to balance groundwater conservation and grain production.

Investigation of Irrigation Erosion in Pseudopodzol Yellow Soils of the Lankaran District

Inclination, length, form and exposition of the slopes affect the irrigation erosion process in the Lankaran district. The artificial rain in a different intensity was created in the tea plantations of the experiment farm of the tea and citrus plants in Lankaran branch in order to study a reason of the surface washing creation in irrigation erosion of the tea plantations more accurately. It was known that a tea plantation in which the rows were built along the slope in 1975, the liquid flow was 125.0 m3/ha, while the rain intensity was 1.0 mm/min., the liquid dissolved dissolved substances flow was 240.0 m3/ha, 2.90 t/ha in the tea plantations built in 1990, while an amount of the leached soil was 0.80 t/ha. Firstly, conduction of the surface smoothing work is recommended in order to prevent from irrigation erosion in irrigated areas with a slope more than 0.02°. Generally, the surface smoothing work is fundamental and current, and it is divided into two places. The current smoothing work begins from preparation of soil for sowing every year and this measure doesn’t require more funds. The fundamental smoothing work is performed for fundamental smoothing of the irrigated sowing areas. At this time an inclination of the areas shouldn’t be more than 0.01. It is recommended to conduct the fundamental smoothing work, then current smoothing work in the areas where the inclination is more than 0.01. Fight against irrigation erosion, definition of the water and irrigation norm, water consumption and realization in the irrigated areas are main problems. The irrigation norm should be determined before for each plant watering. Beside the aforesaid, the technical means (pipes that are made from different materials), including different brands (Fregat, Kuban, KSID-50, Volzhanka, DDA-100 M and so on) rainmaker aggregates, various progressive irrigation methods (artificial precipitation, subsoil irrigation, drip watering, aerosol irrigation, etc.) should be used.

Evaluating optimized irrigation strategies on crop productivity and field water utilization under micro sprinkling irrigation in typical cropping systems of the Huang-Huai-Hai Plain

Inefficient traditional irrigation methods have negative consequences for agricultural production and the depletion of groundwater resources. This two-year field experiment aimed to evaluate optimized irrigation practices for irrigation efficiency (IE) and water utilization in winter wheat-maize (W-M) and winter wheat-soybean (W-S) annual rotation systems. Four micro-sprinkler-based irrigation strategies were implemented during the winter wheat season, specifically when the soil water content (SWC) of the 40 cm soil layer reached 40% of the field capacity (FC) after sowing. Including W4 (irrigated to SWC at 40 cm reached 60% FC), W6 (irrigated to SWC at 60 cm reached 80% FC), FI (farmer's practice, with irrigation amount of 150 mm per irrigation, the same timing as W6), and a rain-fed (RF) as a control. Summer seasons had no irrigation except for emergence. The WHCNS model simulated water consumption. The results indicated that IE decreased with increasing irrigation volumes, and the W-S system demonstrated higher IE than W-M. Both W4 and W6 achieved the desired wetting zones, while FI resulted in water leakage. Surface runoff was not affected by irrigation. Compared to the FI treatment under both cropping systems, W4 significantly reduced field water losses, particularly deep percolation, by 18.3–39.4%. W6 and FI led to elevated winter wheat transpiration rates, impacting crop yield. W4 had comparable yields to W6 and FI, but higher crop water productivity with average increases of 17.9% and 21.3% in W-M, and 24.6% and 31.4% in W-S, respectively. W4 also showed higher harvest indexes in both systems. The W-S system had more stable interannual yields, higher water-holding capacity, and water use efficiency than W-M. Although RF had great water-saving potential, its yield losses were enormous. These optimized precision irrigation strategies significantly reduce water consumption while achieving substantial yield increases, thereby providing vital support for sustainable agricultural development.

Effect of salinity and drip fertigation on maize (<i>Zea mays</i>) and water use efficiency

Climatic variability is immensely pressurised on freshwater availability in arid and semi-arid ecosystems, leading to poor quality water for crop production not becoming uncommon, especially in coastal ecosystems. A field experiment was conducted during winter (rabi) season of 2022–23 at the Saline Water Scheme at Agricultural College Farm, Acharya N. G. Ranga Agricultural University, Bapatla, Andhra Pradesh to assess the impact of saline water on maize growth, yield and water use efficiency under drip fertigation. The experiment consisted 8 treatments laid in randomized block design (RBD) with 4 replications. The utilization of the BAW irrigation method, together with the application of a prescribed quantity of fertilizer, resulted in the highest plant height and dry matter accumulation during all phases of crop growth. These outcomes were comparable to those achieved by using a combination of fresh water and saline water with an electrical conductivity of 2 dS/m. The maximum values for the number of kernels per cob (451), cob length (17.2 cm), cob weight (164.4 g), kernel yield (7.38 t/ha), stover yield (9.61 t/ha) and water use efficiency (18.5 kg/ha mm) of maize were observed under the irrigation treatment T4. The parameters exhibited their minimum values when irrigation was conducted using water with a salt level of 4 dS/m and no fertilizers were used. However, there was no statistically significant difference observed in the number of cobs per plant and harvest index of maize when saline water was used in conjunction with drip fertigation. In the context of maize cultivation, employing a cyclic irrigation technique that alternates between salty (EC 2–4 dS/m) and freshwater sources, in conjunction with recommended dose of fertiliser (RDF) has the potential to deliver comparable crop development, productivity, and economic benefits when compared to the use of freshwater sources alone.

Quinoa growth and yield, soil water dynamics, root growth, and water use indicators in response to deficit irrigation and planting methods

To address the growing issue of scarce water in the arid and semi-arid areas, it is essential to investigate the potential of drought tolerant crops and implement promising farm management strategies to improve water productivity and yield production. Therefore, a split plot experiment to investigate how different irrigation levels (I-1:100% water requirement (WR), I-2:75%WR, and I-3: 50%WR) and planting methods (P-1: basin, P-2: on-ridge, and, P-3: in-furrow) interact and affect quinoa water use, yield, root growth, and water productivity in southern Iran over two growing seasons. The results showed high seasonal crop evapotranspiration (993–1030 mm) in I-1 as a result of the high advection ratio (α), which ranged from 1.02 to 1.46 from the early vegetative to the seed filling stages. The P-3 increased transpiration rate by 4.5% and 7.7%, and decreased soil evaporation by 17% and 29% compared to P-1 and P-2, respectively. Single (Kc) and dual (Kcb + Ke) crop coefficients varied between 0.41 and 1.38 over the two growing seasons. Grain yield in P-3 were 25%, 34%, and 44% higher compared to P-1 and P-2 under I-1, I-2 and I-3, respectively. The study revealed that nearly 67% and 80% of the total root dry matter was in the 0–30 cm and 0–60 cm of the soil profile in all experimental treatments, respectively. Regardless of irrigation treatment, root length density (RLD) and root mass density (RMD) were found to be 18.9% and 15.7% lower in P-1’s top 0–20 cm of the soil profile than those obtained in P-2 and P-3, respectively. Analyses showed that the increased root length in deeper soil layers contributed to higher soil water uptake, and consequently higher crop water productivity. In addition, root-to-shoot ratio increased as the amount of the applied irrigation water was decreased. Quinoa exhibited the highest acclimation to water stress in P-3 based on water stress sensitivity coefficients (λi) and yield response factor (Ky) values. Crop water productivity (WPC) and irrigation water productivity (WPI) for grain yield varied between 0.17 and 0.28 kg m−3. In conclusion, in terms of grain yield, shoot and root dry matter and water productivity, I-2 and P-3 (75% WR irrigation level and in-furrow planting method treatment) is recommended as the optimum water and planting management strategy for quinoa cultivation in the study area as a measure to address water scarcity and food sustainability. Still, to improve yield and irrigation water efficiency, the effect of soil management practices such as mulching and organic amendments on soil water retention and nutrient availability for quinoa should be investigated.

Water use characteristics of an early and late maturing maize hybrid using stable isotopes

AbstractWater requirements of early‐maturing (EM) maize hybrids might be lower than those of late‐maturing (LM) maize hybrids. This study aimed to analyze the effects of different irrigation management on grain yield (GY), water uptake patterns, evaporation (E), and transpiration (T) of two maize hybrids differing in maturity via stable isotope method. The field experiment with 36 lysimeters (4‐m wide × 4‐m long) under rain‐shelters was conducted with an EM (DH518) and a mid‐maturing and LM (DH605) hybrid with three replicates from 2021 to 2022. Maize plants were grown under three irrigation amounts (W1, W2, and W3 were irrigated to maintain soil moisture at 45%, 60%, and 75% of field capacity, respectively) by flood irrigation (FI) and drip irrigation (DI) under rain‐out shelters. Results showed that GY and evapotranspiration (ET) of EM were 8% and 12% lower, while the crop water productivity (CWP) was 6% higher than that of LM. Water uptake of both hybrids occurred mainly within 0‐ to 60‐cm soil layer during the vegetative stage. Water uptake of both hybrids occurred mainly within 0‐ to 60‐cm soil layer during the vegetative stage. Summer maize under FI absorbed more water from the deep soil layer than DI in the late growth stage. Compared with LM, the water absorption depth of EM became shallower in the late growth stage. Water uptake of maize was mainly from the deeper soil under water stress conditions. E of total ET accounts for 43% under DI and 57% under FI; GY and CWP were 22% and 51% higher than those of FI. Together with choosing EM hybrids, optimization of water management with DIW3 could achieve higher GY and CWP. The optimization of irrigation method and hybrids could provide a reference for local farmers to improve GY and CWP.

Influence of Drip Irrigation and Fertigation Levels on Physiological Characters and Yield of Aerobic Rice (Oryza sativa L.)

Background: Water shortage is becoming severe in many rice growing areas in the world. Conventional method of irrigation, which not only consumes huge water, but also causes severe water and nutrient losses under anaerobic condition. Introduction of aerobic rice, growing high yielding rice in non-puddled and non-flooded aerobic soil with the support of external inputs like supplementary irrigation, manures and fertilizers can reduced water use and increase rice production. Methods: Study on different levels of drip irrigation and fertigation on physiological characters and yield of aerobic rice was conducted during summer 2022 and 2023 at research farm of wetland in Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu. The experiment was laid out in randomized complete block design with thirteen treatments, replicated thrice. Result: The findings revealed that drip fertigation @ 100% PE up to 30 DAS+150% PE up to 60 DAS+200% PE up to 90 DAS with 125% RDF (25% through NF+75% through WSF) resulted significantly higher leaf area index (5.84 and 5.95), chlorophyll index (SPAD) (41.5 and 42.3) and grain yield (4315.9 and 4446.1 kg ha-1) respectively than all other treatments during both summer 2022 and 2023. However, significantly lower leaf area index (2.70 and 2.91), chlorophyll content (31.9 and 32.2) and yield (2301.0 and 2364.8 kg ha-1) observed with fertigation at 50% PE up to 30 DAS+100% PE up to 60 DAS+150% PE up to 90 DAS with 75% RDF (75% through NF+25% through WSF), respectively in summer 2022 and 2023.

Worldwide productivity and research trend on fruit quality: a bibliometric study.

As one of the important sources of food for human beings, fruits have been extensively studied. To better guide basic and applied research, it is urgent to conduct a systematic analysis of these studies based on extensive literature collection. Based on the Web of Science Core Collection database, this study uses R language and CiteSpace to conduct bibliometric analysis and data mining on the literatures related to fruit quality from January 2013 to June 2023. The results indicated that among various fruits, tomatoes have been most frequently studied with special interests in photosynthesis, fruit development, and molecular breeding. The research direction primarily focused on fruit resistance and storage characteristics. Among the indicators related to fruit quality, antioxidant activity has the highest co-occurrence with other indicators of fruit quality, especially with nutrients such as anthocyanins, phenolic substances, sugars, and fruit firmness. Currently, adaptation to stress and antioxidant activity are recognized as prominent research focal points in this field. Fruit morphology, particularly fruit size, irrigation methods, application of molecular technology, and infection prevention, represent potential areas of interests in future research on fruit quality.

An Ex-vivo Comparative Study to Evaluate the Efficacy of Three Root Canal Irrigation Systems in Reduction of Enterococcus Faecalis.

The purpose of this ex-vivo study is to evaluate the efficacy of three irrigation techniques in the reduction of E. faecalis in root canal. Eighty healthy maxillary anteriors were employed in this investigation. The bacteria E. faecalis was left on teeth for 7 days while they were kept. Once teeth were contaminated, they were randomly divided into three groups of 20 for experimentation and a control group of 20 for comparison. NaviTip FX was used to irrigate Group I, the Max-I-probe was used to water Group II, and the Endovac system was used to water Group III. The number of colony forming units (CFUs) was determined by growing bacteria from root canal samples for 2 days in Brain heart infusion agar after chemo-mechanical operations. There was a substantial decrease in bacterial numbers across all experimental groups compared to group IV (control). Group III (Endovac) had the fewest bacterial colonies among the test groups. There were no discernible changes between Group I (the Navitip FX) and Group II (the Max I probe). Endovac was the most effective of the three irrigation methods for reducing CFUs. This study's findings lend credence to the idea that the apical negative pressure approach has more potential than the conventional irrigation delivery system for achieving an enhanced antibacterial impact.

Growth and Yield Response of Pea (Pisum sativum L.) Crop to Classical and Regulated Deficit Irrigation along with Nitrogen Fertilization under Drip Irrigation

Background: The conventional methods of applying water and nutrient results lot of wastage and negatively affect the soil, environment and crop response of pea. Methods: The experiments were conducted at Lovely Professional University, Punjab during two years. The five drip irrigated treatments having full irrigation, classical deficit irrigation and regulated deficit irrigation in combination same level of nitrogen fetigation @90% recommended dose of nitrogen (RDN) were taken in 4 replications. One control plot (having flood irrigation with soil application of nitrogen @100% RDN through broadcasting) was taken for comparison. Result: Plant growth, yield contributing parameters, pod yield and water use efficiency (WUE) were significantly affected by drip irrigation in combination with 90% RDN through fetigation over conventional method of irrigation and fertilizer application. Among all the drip irrigated treatments, the increment in crop yield, WUE and irrigation water saving varied from 27.6 to 65.7%, 63.6 to 99.7% and 26.1 to 44.6%, respectively over control plot. In case of same nitrogen fertigation level, the yield and water use efficiency of drip irrigated pea crop can be improved by adoption of moderate water deficit level (which is 15% less than full IWR) under regulated deficit irrigation approach over full irrigation approach. The findings of the work can be utilized by farm managers for irrigation planning and nitrogen management for pea crop and by policy makers to conserve available fresh water resources in water scares regions.

Production-water user association performance nexus in mediterranean irrigated agriculture: The case of banana in Türkiye

In this study, the relationship between the increasing banana production in the Mediterranean region of Türkiye and the performance of Water User Associations (WUAs) is investigated. The increase in banana production due to economic incentives and nutrient demand has triggered a complex nexus of challenges and opportunities in the context of water resource management. The effect of banana production areas on performance of WUAs has not been studied in the region in terms of statistical evaluation. Principle component analysis sheds light on several critical dimensions, including irrigation water use, methods, management, operation and maintenance costs, production value, and water supply ratio, all of which are affected by the expansion of banana cultivation. The findings underline the urgency of adaptive strategies and sustainable practices within the scope of WUAs to meet the growing demand for irrigation water, promote water-efficient technologies, and mitigate economic and environmental consequences. As a result of the research, it has been observed that increasing banana production areas ensures more efficient use of water, improves performances related to production value, and reduces operating, maintenance, and management costs per unit service area.

Ecology and economics of irrigation in the south of Ukraine following destruction of the Kakhov reservoir

ABSTRACT The rupture of the Nova Kakhovka dam on 6 June 2023, resulted in the termination of water distribution to southern Ukraine and Crimea, affecting 750 000 ha of farmland that relied on irrigation. The Kakhov irrigation system serves as a case study to demonstrate the organisation of crop rotation and the economic viability of irrigated farming. We also consider the potentials of future agricultural development in the region and a novel conceptual strategy for water management and changes in irrigation methods to conserve energy and resources.

Water-food-energy nexus assessment for major agricultural crops and different irrigation methods of Lake Urmia basin, Iran

ABSTRACT In this study, the water-food-energy nexus in the Lake Urmia basin was investigated to establish a balance between water and energy consumption, aiming to protect the environment and ensure food security. The research was conducted on 17 farms located in different parts of the Lake Urmia basin, encompassing the predominant crops in the region as well as a variety of irrigation systems. An integrated water-food-energy nexus index was developed, which included irrigation application efficiency, water productivity, energy ratio, energy efficiency, various water footprints and the carbon footprint. The implementation of drip irrigation systems can significantly reduce potential harm to water and energy resources, and the environment.

Choice of an Irrigation Method for Maize Cultivation in a Local Productive Arrangement Using the SAPEVO-M Method

Corn crops can be irrigated using surface irrigation methods (furrows, horizontal pots, strips), as well as fixed or mobile sprinklers under canopy and localized irrigation (drip and micro sprinklers). The selection of the most appropriate irrigation method and system for a particular situation depends on an assessment of the available physical resources, such as water supply (quantity, quality and location), soil properties (texture, structure, depth, salinity, drainage, topography, erodibility) and plant climate systems, in which the adaptability of crops to the climatic conditions of each site must be taken into account. In this sense, the objective of this work is to select an irrigation method for a corn plantation in a Local Productive Arrangement (LPA). For this study, six irrigation methods were pre-selected as alternatives, and seven pre-established comparison criteria were unstructured interviews with stakeholders. The solution of the problem was carried out using the Multicriteria Decision Analysis model Simple Aggregation of Preferences Expressed by Ordinal Vectors – Multi Decision Makers (SAPEVO-M). After modeling the problem with the decision-makers, the method indicated the drip irrigation system as the best alternative.

The Influence of Sprinkler and Drip Irrigation on the Incidence and Severity of Bacterial Disease in Onions Grown in Northeast California

Overhead sprinkler irrigation and its effect on leaf wetness are often referenced as a key factor for bacterial disease spread in onions grown in arid climates. A study was conducted in 2021 and 2022 in Tulelake, California, to compare the incidence and severity of bacterial disease under sprinkler and drip irrigation. The experiment was a split-plot randomized complete block design with drip and solid-set sprinkler irrigation as the main plot treatments and inoculation and no inoculation with plant-pathogenic bacteria as the split-plot treatments. The entire study area was irrigated with solid-set sprinklers from planting until the five-leaf stage to facilitate uniform onion germination and chemigation of herbicides for weed control. After the five-leaf stage, irrigation treatments were imposed for the remainder of the growing season. Total irrigation water amount and irrigation frequency were similar for both irrigation methods. Foliar disease severity and the incidence of bulb rot were 170 and 186% higher, respectively, for solid-set sprinkler compared with drip irrigation. Leaf wetness within the plant canopy during onion bulbing was on average 36% higher in the solid-set sprinkler compared with drip irrigation treatment, whereas relative humidity and temperature were similar between irrigation methods. Drip irrigation maintained lower soil water tension and increased average bulb size by 9% compared with solid-set sprinkler irrigation. This study confirms historical observations that overhead irrigation can extend leaf wetness and increase bacterial disease in onions in arid production areas and highlights the potential benefits of the adoption of drip irrigation.

Subsurface Seep Irrigation Effects on Omnivorous Nematode Vertical Distribution in Lysimeters

Subsurface seep irrigation is a common practice in Florida histosol soils to supply water to crops by utilizing high-water tables. This study evaluated the effect of subsurface and overhead irrigation methods on plant-parasitic and free-living nematode densities in 46-cm soil lysimeters in a greenhouse study. Lysimeters were planted with bahiagrass in 2019 and wheat in 2020 and irrigated with subsurface or overhead irrigation for 12 weeks. Nematodes were extracted and quantified at 5-cm depth increments. Nematode counts were subjected to analysis of variance to compare treatment effects. Among nematode functional groups, omnivores were the most affected by irrigation method, their abundance being lower in subsurface-irrigated lysimeters than in overhead-irrigated ones. The results of this study show that omnivore nematode density and depth distribution are impacted by irrigation method.

COMPARATIVE ASSESSMENT OF THE ROOT CANAL IRRIGATION QUALITY WITH EXPERIMENTAL INTRA-ROOT RESORPTION IN VITRO

Introduction. To date, intra-root resorption of teeth is poorly understood, although it is often encountered in dental clinics. This study aimed on assess and comparison of different methods of irrigation and antiseptic solutions activation used for root canal treatment, and focus on cleaning the area of simulated intra-root resorption. Methods. 24 extracted teeth were used, which the simulation of internal resorption was reproduced by dissection the inside of the root canal under the control of an electron microscope (Karl Kaps, Germany) in. Distilled water, sodium hypochlorite 5.25 %, sodium hypochlorite 3 %, chlorhexidine 2 % were used for comparative assessment of irrigation quality by staining with Indian Ink dye. Results. When using an endodontic needle and passive irrigation with the studied irrigation solutions, the dye remained on the inner surfaces of the root canal walls, which indicated their insufficient cleaning. The use of auxiliary cleaning methods - sound and ultrasonic irrigation nozzles - showed better cleaning of the root canal resorption zone. When using the sound activation of the irrigator with the EndoActivator device, the dye partially remained in the simulated resorption zone, while a significant part of the root canal system was cleaned. The use of ultrasonic activation of the irrigator with the P5 XS device showed that all dye-stained root canals of the samples were cleaned. Zones of simulated root resorption did not show any dye residues visually and under electron microscope control. Conclusions. The quality of root canal cleaning in case of intra-root resorption in terms of visual assessment of their transparency and under the control of an electron microscope was more pronounced when using methods of activating irrigation solutions with sound and ultrasonic activators.

Cotton irrigation regime under the mole irrigation method in the south of Russia

Studies on developing optimal soil water regimes under mole irrigation of cotton compared with sprinkling and drip irrigation were conducted in 2023 on light-chestnut soils of southern Russia. As a result, it was found that under mole irrigation, with increasing the pre-watering threshold of soil moisture from 70-70-65 to 80-80-75 % of the lowest water holding capacity (LWC) irrigation rates decreased from 250...290 to 170...210 m3/ha and the number of irrigations and irrigation rate increased from 4 to 7 units and from 1040 to 1270 m3/ha. A comparison of irrigation methods showed that under mole irrigation, in comparison with drip irrigation, irrigation rates increased by 7.4. 13.3 %, and the number of irrigations per season and irrigation rate decreased by 1...2 units and 11.2...12.6 %, respectively. Compared to sprinkling, irrigation rates and total amount of water decreased by 45.2...46.3 and 28.8...34.5 %, respectively, and the number of irrigations increased by 1 unit. It was also found that maintaining a moisture availability level of 75-75-70 % LWC created optimal conditions in cotton crops, which, combined with mineral fertilizer application with doses N140P60K45, allowed the highest cotton yield under mole irrigation of 3.18 t/ha. When sprinkling on a similar option, it decreased by 0.21 t/ha, and at drip irrigation, it increased by 0.13 t/ha.

Effect of drought stress on morpho-physiological characteristics, nutritive value, and water-use efficiency of sorghum [Sorghum bicolor (L.) Moench] varieties under various irrigation systems.

Addressing water scarcity and the need for high-quality forage in arid regions necessitates the development of efficient irrigation techniques. This study assesses the impact of various irrigation methods on the performance and irrigation water-use efficiency (IWUE) of sorghum cultivars under water-deficit conditions in a semi-arid region of Iran during the 2019 and 2020 cropping seasons. Three irrigation methods-variable alternate furrow irrigation (AFI), fixed alternate furrow irrigation (FFI), and conventional furrow irrigation (CFI)-were evaluated alongside three levels of drought stress (severe stress: I50, moderate stress: I75, and full irrigation: I100) and two sorghum cultivars. The results indicated that increasing drought stress, as well as the transition from CFI to AFI and FFI, led to reductions in metabolizable energy yield (MEY), plant height, cellulose, hemicellulose, and lignin. Conversely, there were increases in leaf-to-stem ratio, digestible organic matter, metabolizable energy content, crude protein content, and IWUE for metabolizable energy production (IWUEME). The highest MEY (211.68 GJ ha-1) was recorded under CFI×I100, albeit at the expense of maximum water consumption (7261 m3 ha-1). Meanwhile, the AFI×I50 and FFI×I50 treatments exhibited the highest IWUEME (44.46 MJ m-3) and metabolizable energy content (8.736 MJ kg-1), respectively, while conserving over 60% of water. Hybrid Speedfeed outperformed in forage yield and IWUEME, while cultivar Pegah excelled in forage quality. Transitioning from CFI to AFI or FFI resulted in decreased forage yield but improved forage quality and IWUEME. Principal component analysis revealed that leaf-to-stem ratio and plant height serve as effective indicators for assessing the nutritive value and forage yield of sorghum, respectively. Considering the overall results, cultivating the hybrid Speedfeed under AFI×I75 conditions is recommended for optimal water utilization, achieving satisfactory forage yield and quality, and enhancing IWUE.