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Measuring the soil water content (SWC) is a fundamental component of the sustainable management of water resources, soil preservation, and high irrigation efficiency. Non-destructive SWC measurements using soil moisture sensors (SMSs) enables timely irrigation and reduces overirrigation and water stress. Within this context, the performance of four commercial single-point soil moisture sensors (Watermark and tensiometer (Irrometer Company, Inc., Riverside, CA, USA), SM150 (Delta-T Devices, Cambridge, UK)), FieldScout TDR300 (Spectrum Technologies, Aurora, IL, USA) and one soil profile PR2 probe (Delta-T Devices, Cambridge, UK) were tested under anthropogenic eutric cambisol with a silty clay loamy texture (20, 30, and 40 cm) to evaluate accuracy and sensitivity to changes in the SWC in an irrigated apple orchard. The Watermark and tensiometer were additionally tested in the laboratory to convert soil water tension (kPa) to the volumetric soil water content (%vol.). In general, all tested SMSs responded to changes in the SWC, with sensor-to-sensor differences. The Watermark and tensiometer underestimated the SWC, while the TDR overestimated the SWC. The SM150 and PR2 showed high accuracy, i.e., SM150—RMSE-2.24 (20 cm), 2.18 (30 cm) and 2.34 (40 cm), MSE—5.02 (20 cm), 2.93 (30 cm) and 1.89 (40 cm), and PR2—RMSE-1.8 (20 cm), 1.3 (30 cm) and 1.55 (40 cm), MSE-3.23 (20 cm), 1.7 (30 cm) and 2.39 (40 cm) at all observed soil depths. [ABSTRACT FROM AUTHOR]

Climate change is causing serious problems in various economic sectors in particular involving water management. For this reason, it is extremely important to conduct research to identify climate change trends and better understand them. This study was carried out in the Dim Stream basin in the Western Mediterranean region (Turkey), which is particularly vulnerable to climate change. The study used flow data from two flow observation stations (FOS) and meteorological records such as wind speed, average flow, precipitation, temperature, evaporation, radiation, and relative humidity for 1984-2017. These data showed the changes between flow and hydrometeorological variables using linear regression analysis, coefficient of variation, t-test and correlation analysis. It has been determined that there has been a rapid decrease in the average flow of the FOS number 09-006 since 1995 and the average flow of the FOS number 09-013 since 1999. Also, it was demonstrated that the average relative humidity (RH ave), average temperature (T ave), average precipitation (Pave), total precipitation (Pt) and maximum precipitation (P max) meteorological variables were most affected by climate change in the basin. Furthermore, it was found that the most changes were Qy ave (67.60%), T min (48.23%), P max (36.43%), P ave (33.91%), P t (33.90%), and RH ave (2.63%) in FOS numbered 09-013. Moreover, it was concluded that climate change variability had developed trends towards a rapid decrease in the flow values at the flow observation stations in Dim Stream. These results show that plans and measures for the efficient and sustainable management of water resources in this region must be implemented immediately. [ABSTRACT FROM AUTHOR]

Copyright of Glasnik Zastite Bilja is the property of Zadruzna Stampa D.D. 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.)

The paper presents research on measuring and the possibility of prediction of noise levels on the left and right sides of the operator within the cabin of an agricultural tractor when moving across various agrotechnical surfaces, considering movement velocity and tire pressures while employing machine learning techniques. Noise level measurements were conducted on a LANDINI POWERFARM 100 type tractor, and aligned with standards (HRN ISO 5008, HRN ISO 6396 and HRN ISO 5131). The obtained noise values were divided into two data sets (left and right set) and processed using multiple linear regression (mlr) and three machine learning methods (gradient boosting machine (gbm); support vector machine using radial basis function kernel (svmRadial); monotone multi-layer perceptron neural network (monmlp)). The most accurate method, considering surfaces, from the left side data set—(R2 0.515–0.955); (RMSE 0.302–0.704); (MAE 0.225–0.488)—and the right side—(R2 0.555–0.955); (RMSE 0.180–0.969); (MAE 0.139–0.644)—was monmlp predominantly, and to a lesser extent svmRadial. On analyzing the total data sets from the left and right sides regarding surfaces, gbm emerged as the most accurate method. The application of machine learning methods demonstrated data accuracy, yet in future research, measurements on certain surfaces may need to be repeated multiple times potentially to improve accuracy further. [ABSTRACT FROM AUTHOR]

Average monthly air temperatures in Bosnia and Herzegovina (BiH) exhibit a notable rise during summer, ranging from 0.4 to 0.8 °C per decade, while precipitation experiences a significant decrease of up to 8 mm per decade. Climate models, across various RCP scenarios, project an increase in air temperature, that is most pronounced in the summer season. Additionally, there is a projected frequency and intensity of heavy precipitation during autumn. In BiH, agricultural production faces substantial risks, including droughts, spring and autumn frosts, hail, and floods. Recent years have witnessed extreme hydrological events, notably the 2012 drought and the 2014 floods. Strategic documents highlight the critical importance of addressing floods and droughts for agriculture, as well as their implications for the environment, households, and industry. To assess the severity of extreme hydrological events and their impact on agriculture, with a specific emphasis on autumn and summer in Bosnia and Herzegovina, average and peak values of the Standardized precipitation evapotranspiration index (SPEI) were calculated separately for the periods 1961-1990 and 1991-2020, focusing on October and August. Compared to the reference climatic period the current climate is characterized by shifts between intense wet and dry periods, with very few years exhibiting stable and expected weather conditions. Identified as extremely wet and flood-prone years, SPEI2 October values for 1974 (2.42), 1996 (2.13), 2001 (2.24), and 2014 (2.05) stand out, with only one extremely dry year in 1985 (-2.21). SPEI2 August indicates extremely dry years, notably 2012 (-2.35) and 2017 (-2.25). [ABSTRACT FROM AUTHOR]

The air temperature in Bosnia and Herzegovina is increasing (0.3 - 0.6 °C per decade), while rainfall events are more extreme. Additionally, there is an increased variability in weather conditions across all seasons, marked by rapid shifts from extremely cold to warm weather, as well as transitions from periods of exceptionally high rainfall to exceedingly dry periods. Droughts and floods pose the most significant risks. However, Bosnia and Herzegovina faces a lack of adequate information and analyses of extreme climate events, especially regarding their timing, intensity, magnitude, duration, and spatial extent. Therefore, this study aims to address these questions using the precise drought index SPEI. The identified wet years were: 1969, 1970, 1976, 1978, 1999, 2001, 2010, 2013, and 2014, while the dry years were 1961, 1971, 1983, 1990, 2000, 2003, 2007, 2011, 2012, and 2020. In the northern and western regions of BiH, the longest wet period in terms of duration and spatial extent occurred from May 2014 to July 2015. In the central and southern parts of BiH, the longest wet period extended over 19 months from February 1969 to August 1970. The longest drought with the largest spatial extent was the drought from August 2011 to July 2013. The obtained data shows a significant shift towards drier weather, as dry months have increased by 15% compared to wet months. At the same time, there has been a decrease in near-normal conditions and an increase in extremely wet months. [ABSTRACT FROM AUTHOR]

Morphological and biochemical responses were assessed in an iceberg (GIL) and butterhead (GBL) lettuce (Lactuca sativa var. capitata) treated with commercially available soluble preparation of mycorrhizal fungi and beneficial soil bacteria (MT) grown in three irrigation treatments considered in greenhouse (continental Croatia, 2022): I100—control treatment (100% volumetric water content—VWC); I80—80% VWC, moderate drought and I60—60% VWC, severe drought), in two growing cycles. MT was applied during lettuce drought-sensitive stages, i.e., transplanting and heading. Study results show that MT improved lettuce growth-related traits, yet the results are genotype and growing-cycle dependent. The beneficial effect of MT was also noted for root length, weight, and diameter which confirms the mycorrhizal role in improving the plant water uptake. Both lettuce genotypes responded to water deficit by overproduction of MDA and proline content, whereby the response of tested variables was growing cycle and genotype-specific. Both genotypes in severe drought treatment (MT-I60) responded with higher MDA in the first growing cycle and lower MDA content in the second growing cycle. MT-I60 treatment reduced proline accumulation in GBH in both growing cycles, while increased accumulation in GIL during the second growing cycle. The responses of lettuce to MT are genotype-specific and shaped by environmental conditions. [ABSTRACT FROM AUTHOR]

At present there is little information available concerning the relationship between the tillage system applied and the soil moisture tension, penetration resistance, soil moisture content, and temperature responses to the temporal variability of precipitation under the semi-arid Mediterranean environment. The aim of this study was to determine the effects of standard tillage (ploughing to 25-35 cm) and conservation tillage shallow (loosening to 10 cm) on temporal changes in the three properties in response to the precipitation pattern in Croatia. The temporal changes in soil moisture tension were determined using Watermark sensors (at 15 and 30 cm), and penetration resistance (at 0-30 cm) was determined with an Eijkelkamp penetrometer in spring under winter wheat. After heavy precipitation, the soil moisture tensions were similar irrespective of the tillage system used and the measurement depth, while with the increasing length of the period without precipitation (using the last precipitation incident as the starting timepoint), the soil moisture tensions increased to a greater extent under conservation tillage shallow as compared to standard tillage. The temporal changes in soil moisture tension in response to precipitation were less sensitive at the 30 than at the 15 cm depth. The adoption of conservation tillage shallow increased the amount of topsoil organic matter as compared to standard tillage. This study indicates that conservation tillage shallow is a promising practice in terms of soil quality improvement and crop productivity under highly variable Mediterranean climate conditions. [ABSTRACT FROM AUTHOR]

The climate of Southeastern Europe, where Bosnia and Herzegovina (BiH) and Croatia are located, is changing in line with the global trends. The spatial and seasonal distribution of precipitation is changing, while the temperatures increased 0.4-0.8 oC on average compared to 1961-1990, most notably during summer (1.0-1.2 oC). Depending on the different Representative Concentration Pathway (RCP) scenarios, the temperatures in this area are projected to further increase by 1.7-4.0 °C. In order to understand the effects of climate change on regional water resources, it is important to assess the impacts of these changes on the components of the water balance. The aim of this study was to determine and compare the severity of changes in annual water balance between two climate periods (1961-1990 and 1991-2020). The results indicate that climate change has a different temporal and spatial effect. All areas showed a positive trend in mean air temperature (0.29-0.36 oC per decade), reference evapotranspiration (5.96-32.14 mm per decade) while precipitation, total runoff, amount of snow and actual evapotranspiration vary depending on the location and time period. The key characteristic of the 1991-2020 period compared to 1961-1990 is the greater variation of all components of the water balance. [ABSTRACT FROM AUTHOR]

This four-year study with four elite soybean lines with different maturities was conducted to investigate the impact of deficit (a field water capacity, or FWC, of 60%) and full irrigation (an FWC of 80–100%) on soybean grain yield and grain quality (grain protein and oil contents and crude protein and oil yields), depending on the environmental conditions and genotype. Overall, the irrigation effect was positive for the grain yield and grain protein content but negative for the grain oil content. The differences between the full and deficit irrigation were only 2.9% for the grain yield, 2.8% for the crude protein yield and 1.7% for the crude oil yield. The results indicate that deficit irrigation could be the best option for optimizing soybean production in environments similar to the tested one. In such conditions, further rationalization of soybean production could be achieved by choosing the C2 genotype (0 maturity group), which, combined with deficit irrigation, had the highest grain, crude protein and crude oil yields. [ABSTRACT FROM AUTHOR]

Allelopathy, a biological phenomenon, is a valuable tool for weed management and minimization of synthetic pesticide use in sustainable agricultural production. The aim of the study was to evaluate the allelopathic potential of nine sunflower genotypes. Water extracts from dry sunflower leaves collected in two growth stages (butonisation and flowering) were tested in two concentrations (1 and 2.5%) on germination and growth of lettuce under laboratory conditions. The allelopathic effect of extracts was influenced by genotype, growth stage and extract concentration. The majority of extracts exhibited negative allelopathic potential with seed germination being the least affected, and root length reduced up to 85% compared to the control. A higher concentration of water extracts resulted in a greater reduction of lettuce growth parameters. On average, extracts collected in the flowering stage inhibited lettuce shoot length to a greater degree. Several genotypes showed a greater negative impact, especially on shoot length and seedlings' fresh weight. Further investigations of selected sunflower genotypes with the highest allelopathic potential on weed species and studies on phytochemical analysis are needed. [ABSTRACT FROM AUTHOR]

Copyright of Agronomy Journal / Agronomski Glasnik (0002-1954) is the property of Croatian Society of Agronomists 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.)

Copyright of Glasnik Zastite Bilja is the property of Zadruzna Stampa D.D. 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.)

The study of salinity stress in irrigated floriculture can make a significant contribution to the preservation of freshwater sources. To analyze the morphological and aesthetic responses of zinnia (Zinnia elegans L.) and periwinkle (Catharanthus roseus (L.) G. Don) to different salinity stress levels, the following treatments were performed: s0 = municipal water (control), s1 = 3 dS m−1, s2 = 4.5 dS m−1, and s3 = 6 dS m−1. The growth of zinnia (flower number, plant height, branch and leaf number, total fresh and dry biomass, and root length) was linearly reduced by increasing salinity levels, while all observed periwinkle traits for the s2 salinity treatment were either equal to or greater than the control treatment (n.s.) and a further increase in salinity stress showed a significant (p < 0.01) decrease. The first flower buds on zinnia appeared with the control treatment (s0), while for periwinkle the first flower bud appeared with the s1 treatment. With regard to both zinnia and periwinkle leaf necrosis, drying and firing occurred during the third week in the s2 and s3 treatments. Zinnia proved to be sensitive to salinity, while periwinkle showed mild tolerance to salinity stress, up to 3 dS m−1. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central European Agriculture is the property of Journal of Central European Agriculture 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.)

One of the major challenges for agriculture related to climate change is drought. The increasing temperatures and decreasing precipitation in many parts of the world have enhanced the frequency and severity of drought events. Therefore, a detailed analysis is required in order to determine the drought frequency and take the necessary precautions. In this study, the climatic conditions in the agricultural region of Çukurova (Turkey) were analysed. Meteorological data for the three provinces of Adana, Mersin, and Osmaniye were used. The aim was to calculate the Standardized Precipitation Index (SPI) for each of the three provinces analysed, and to use these values to detect drought during the different growth periods of maize. We also investigated whether the SPI values for the last 30 years differ significantly between the provinces. Furthermore, indicators such as the duration, magnitude, severity, recurrence, and drought frequency were also calculated. Using linear regression analysis, we determined whether there were trends in the multi-year data for the total precipitation and mean temperature. In addition, the water deficiency was determined by examining the amount of water required by maize and the adequacy of the precipitation in each development period. As a result, it was found that the Çukurova region is prone to droughts, but they follow a mild course in most cases. However, no statistically significant differences were observed between the SPI values in the three provinces. The calculated average approximate drought recurrences (Tr) and expected intensities (Iave) were Tr ~ 1.036 years and Iave ~ 5.634 mm year−1 in 3 years for Adana, Tr ~ 1.031 years and Iave ~ −0.312 mm year−1 in 3 years for Mersin, and Tr ~ 1.052 years and Iave ~ −0.084 mm year−1 in 3 years Osmaniye. The research carried out in this paper confirmed that maize cultivation in the Çukurova region is vulnerable to drought, and adaptation actions should be taken immediately. [ABSTRACT FROM AUTHOR]

Copyright of Agronomy Journal / Agronomski Glasnik (0002-1954) is the property of Croatian Society of Agronomists 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.)

Sustainable and profitable crop production has become a challenge due to frequent weather extremes, where unstable crop yields are often followed by the negative impacts of agronomic practices on the environment, i.e., nitrate leaching in irrigated and nitrogen (N)-fertilized crop production. To study this issue, a three-year field study was conducted during quite different growing seasons in terms of weather conditions, i.e., extremely wet, extremely dry, and average years. Over three consecutive years, the irrigation and N fertilizers rates were tested for their effect on grain yield and composition, i.e., protein, starch, and oil content of the maize hybrids; soil N level (%); and nitrate leaching. The results showed that the impact of the tested factors and their significance was year- or weather-condition-dependent. The grain yield result stood out during the extremely wet year, where the irrigation rate reduced the grain yield by 7.6% due to the stress caused by the excessive amount of water. In the remainder of the study, the irrigation rate expectedly increased the grain yield by 13.9% (a2) and 20.8% (a3) in the extremely dry year and 22.7% (a2) and 39.5% (a3) during the average year. Regardless of the weather conditions, the N fertilizer rate increased the grain yield and protein content. The soil N level showed a typical pattern, where the maximum levels were at the beginning of the study period and were higher as the N fertilizer rate was increased. Significant variations in the soil N level were found between weather conditions (r = −0.719) and N fertilizer rate (r = 0.401). Nitrate leaching losses were expectedly found for irrigation and N fertilizer treatments with the highest rates (a3b3 = 79.8 mg NO3− L). [ABSTRACT FROM AUTHOR]

Watermark, Tensiometer and Time Domain Reflectometry (TDR) are commonly used soil water sensors in irrigation practice whose performance depends on soil type, depth and growing conditions. Here, the results of sensor performance evaluation in different soil depths as well as the field and laboratory testing in silty clay loamy soil are presented. Gravimetric soil moisture samples were taken from sensor installation depths (10, 20, 30 and 45 cm) and used as reference Soil Water Content (SWC). The measurements varied significantly (p < 0.05) across the monitoring depths. On average across the soil depths, there was a strong negative linear relationship between Watermark (r = −0.91) and TDR (r = 0.94), and a moderate negative (r = −0.75) linear relationship between SWC and Tensiometer. In general, Watermark and Tensiometer measured SWC with great accuracy in the range of readily available water, generated larger Mean Difference (MD) than TDR and overestimated SWC, while TDR underestimated SWC. Overall, laboratory testing reduced the root mean square error (RMSE, Watermark = 1.2, Tensiometer = 2.6, TDR = 1.9) and Mean Average Error (MAE, Watermark = 0.9, Tensiometer = 2.04. TDR = 1.04) for all tested sensors. [ABSTRACT FROM AUTHOR]

In this study, the AquaCrop model was used to quantify climate change impact on yield and net irrigation in maize and soybean production. Daily observed climate data (1961-1990) from Osijek weather station were used for past climate simulation, and output data from ECHAM model were dynamically downscaled under two IPCC SRES scenarios (A1B, A2) for two integration periods 2041-2070 and 2071- 2100. The soil properties and crop data were presented from 6-year-long (2010-2015) field study of the Agricultural Institute in Osijek, Osijek-Baranja County. The climate results showed expected rise in air temperature up to 5 ºC and significantly lower precipitation up to 43.5%. According to results from the AquaCrop model, there is no change in maize yield in non-irrigated conditions, while in irrigated conditions there is a yield increase of 1.4 t ha-1 of dry matter (dm), with 80 mm higher net irrigation in comparison with the 1961-1990 period. As for soybean production, the increase in yield is expected in both non-irrigated and irrigated conditions. The yield increases up to 1.9 dm t ha-1 in irrigated conditions with 90 mm higher net irrigation in comparison with the 1961-1990 period. As for crop water indices, in non-irrigated conditions the water use efficiency (WUE) has a trend to decrease in the future, while in irrigated conditions it can slightly increase. Irrigation water use efficiency (IWUE) showed significantly higher increase in irrigated maize and soybean production. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Central European Agriculture is the property of Journal of Central European Agriculture 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.)

The paper presents a study of the influence of an uneven surface and number of tractor hours on vibration that is transmitted to the operator's hand-arm system during operation. The study was conducted on the asphalt, gravel and grass traversal during 2015 and 2016. The results indicate that the movement of a tractor on different agrotechnical surfaces generates vibrations of varying intensity that affect the hand-arm system of the operator. The highest vibration values were recorded on the asphalt, while the least vibrations were measured on the grass. The measured maximum vibration values are lower than the permissible 5 m·s-2 in the direction of all three axes, making it possible to assume that they are not harmful to the health of the operator. [ABSTRACT FROM AUTHOR]

Copyright of Agronomy Journal / Agronomski Glasnik (0002-1954) is the property of Croatian Society of Agronomists 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.)

Copyright of Agronomy Journal / Agronomski Glasnik (0002-1954) is the property of Croatian Society of Agronomists 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.)

The paper presents the recorded vibrations that affect the operator's body when an agricultural tractor moves along three types of agrotechnical surfaces, i.e. asphalt, an alfalfa field, and a field path, and when seven different tractor seat upholsteries are used. The research was performed in accordance with the HRN ISO 2631-1 and HRN ISO 2631-4 standards. The tractor used in the research was an IMT 560 and the duration of the measurement was 30 minutes, which was repeated three times for every tractor seat upholstery type. The research was exploitative. The measurements were performed using an MMF VM30 meter. The paper reveals a different level of vibrations in dependence with different surfaces and seat upholsteries. The fewest vibrations were produced by asphalt, and the best upholsteries are memory foam and sponge. [ABSTRACT FROM AUTHOR]

Copyright of Genetika (0534-0012) is the property of Serbian Genetics Society 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.)

Copyright of Glasnik Zastite Bilja is the property of Zadruzna Stampa D.D. 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.)

Copyright of Glasnik Zastite Bilja is the property of Zadruzna Stampa D.D. 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.)

Copyright of Agronomy Journal / Agronomski Glasnik (0002-1954) is the property of Croatian Society of Agronomists 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.)

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell 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.)

Copyright of Journal of Central European Agriculture is the property of Journal of Central European Agriculture 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.)

Copyright of Journal of Agricultural Sciences, Belgrade is the property of University of Belgrade, Faculty of Agriculture 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.)

Deficit irrigation of soybean was induced by irrigation at 60-100% field water capacity (FWC) during three different climatic years in sub-humid area. Crop evapotranspiration (ETc) was measured for each irrigation plots, dry-land (a1), deficit irrigation (a2) and full irrigated plots (a3). Average across years ETc totalled 46.05 mm/dec from initial to late stage. Kc values ranged from 0.35 at vegetative stage, 1.0 at reproductive stage after what it declines to 0.82. In deficit irrigated plots grain yield of soybean was increased as compared to control plots by 7.5% (2006), 1.15% (2007) and 7.3% (2008). In average climate years (2006 and 2008), by increasing soil water content at full irrigated plots (80-100% FWC), grain yield of soybean was reduced by 1.9% (2006) and 5.8% (2008) in comparison to deficit irrigated plots. This was in contrast to results obtained in extremely warm and very dry year 2007, when the highest yield was at full irrigated plots (3.68 t ha-1). Averaged across years, the highest irrigation water use efficiency was at deficit irrigated plots (0.3 to 3.3 kg m-3). Results obtained from this research showed that deficit irrigation management is an efficient measure for preserving water resources and achieving high yields in average climate years. [ABSTRACT FROM AUTHOR]

Irrigation efficiency improvement requires optimization of its parameters like irrigation scheduling, threshold and amount of water usage. If these parameters are not satisfactorily optimized, negative consequences for the plant-soil system can occur with decreased yield and hence economic viability of the agricultural production. Numerical modelling represents an efficient, i.e. simple and fast method for optimizing and testing different irrigation scenarios. In this study HYDRUS-1D model assuming single- and dual-porosity systems was used to evaluate a triggered irrigation module for irrigation scheduling in maize/soybean cropping trials. Irrigation treatment consisted of two irrigation regimes (A2 = 60-100% field capacity (FC) and A3 = 80-100% FC) and control plot (A1) without irrigation. The model showed a very good fit to the measured data with satisfactory model efficiency values of 0.77, 0.69, and 0.93 (single-porosity model) and 0.84, 0.67, and 0.92 (dual-porosity model) for A1, A2, and A3 plots, respectively. The single-porosity model gave a slightly better fit in the irrigated plots while the dual-porosity model gave better performance in the control plot. This inconsistency between the two approaches is due to the manual irrigation triggering and uncertainty in field data timing collection. Using the triggered irrigation module provided more irrigation events during maize and soybean crop rotation and consequently increased cumulative amounts of irrigated water. However, that increase resulted in more water available in the root zone during high evapotranspiration period. The HYDRUS code can be used to optimize irrigation threshold values further by assuming different scenarios (e.g. different irrigation threshold or scheduling) or a different crop. [ABSTRACT FROM AUTHOR]