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The radioactive fission product 90Sr has a sufficient half-life (28.8 years) to be detected long after its appearance in the environment. After its uptake into the soil-edible plant system, it enters the food chain and represents a potential source of contamination that threatens human health. Due to these facts, tracking the distribution of the artificial radionuclide 90Sr in the soil–edible plant system is a subject of intense research. The tracking of the 90Sr radionuclide distribution in the soil profile, as well as in the crops on the long-term experimental fields was carried out using beta radiation spectrometry. The radiochemical analytical method was used to analyze the 90Sr content in cultivated soil and crops. The conducted study focused on the experimental substantiation of the developed model for predicting the behavior of 90Sr in the cultivated soil–crop system. The results of using the applied radioecological model for the transfer of 90Sr from the soil to the above-ground part of crops showed a relatively good agreement with the experimentally determined values of the soil–crop transfer factor, which indicates that the used model can be successfully applied for the prediction of the behavior of 90Sr in the soil–soil solution–crop system. [ABSTRACT FROM AUTHOR]

Biochar can significantly alter soil properties and therefore can play an important role in increasing the resilience of agricultural systems to salt conditions. To match biochar to salt-affected soil constraints and application needs, a thorough understanding of the impact of biochar, soil properties and experimental conditions on crop productivity and soil salinity is necessary. This meta-analysis (MA) of the available literature for the first time quantitatively assessed the effect of not only biochar applied to salt-affected soils but also that of different salt-affected soil properties on crop productivity and soil salinity. The results showed that biochar was most effective at improving crop productivity in salt-affected soils, with an application rate ranging from 40–50 t/ha, a C/N ratio ranging from 40–60, a pyrolysis temperature ranging from 450–550 °C and a pH ranging from 7–8. Biochar with an EC of < 2 mS/cm, an application rate of 20–30 t/ha, a C/N ratio of > 80 t/ha or a pyrolysis temperature of < 450 °C reduced the soil salinity. Regardless of climatic and soil conditions, biochar applied to salt-affected soils increased crop productivity under different climatic conditions. Biochar increased soil salinity under different temperature and soil pH conditions and decreased soil salinity in salt-affected soils treated with all types of salts. Biochar was most effective at improving crop productivity and soil salinity in sulfate-dominated saline soils. Regardless of the planting and management practices, biochar increased crop productivity in salt-affected soils. The combined application of biochar and inorganic fertilizer significantly increased crop productivity and kept soil salinity unchanged. This meta-analysis provides the first quantitative review of the effect of biochar on crop productivity and soil salinity in salt-affected soils, which is critical for developing engineered biochar to restore salt-affected soils and promote food security. [ABSTRACT FROM AUTHOR]

An optimization method of fracturing fluid volume strength was introduced taking well X-1 in Biyang Sag of Nanxiang Basin as an example. The characteristic curves of capillary pressure and relative permeability were obtained from history matching between forced imbibition experimental data and core-scale reservoir simulation results and taken into a large scale reservoir model to mimic the forced imbibition behavior during the well shut-in period after fracturing. The optimization of the stimulated reservoir volume (SRV) fracturing fluid volume strength should meet the requirements of estimated ultimate recovery (EUR), increased oil recovery by forced imbibition and enhancement of formation pressure and the fluid volume strength of fracturing fluid should be controlled around a critical value to avoid either insufficiency of imbibition displacement caused by insufficient fluid amount or increase of costs and potential formation damage caused by excessive fluid amount. Reservoir simulation results showed that SRV fracturing fluid volume strength positively correlated with single-well EUR and an optimal fluid volume strength existed, above which the single-well EUR increase rate kept decreasing. An optimized increase of SRV fracturing fluid volume and shut-in time would effectively increase the formation pressure and enhance well production. Field test results of well X-1 proved the practicality of established optimization method of SRV fracturing fluid volume strength on significant enhancement of shale oil well production. [ABSTRACT FROM AUTHOR]

Wheat is the main grain crop in our country, and the traditional wheat yield estimation method is time-consuming and laborious. By estimating wheat yield efficiently, quickly and non-destructively, agricultural producers can quickly obtain information about wheat yield, manage wheat fields more scientifically and accurately, and ensure national food security. Taking the Xinxiang Experimental Base of the Crop Science Research Institute, Chinese Academy of Agricultural Sciences as an example, hyperspectral data for the critical growth stages of wheat were pre-processed. A total of 27 vegetation indices were calculated from the experimental plots. These indices were then subjected to correlation analysis with measured wheat yield. Vegetation indices with Pearson correlation coefficients greater than 0.5 were selected. Five methods, including multiple linear regression, stepwise regression, principal component regression, neural networks and random forests, were used to construct wheat yield estimation models. Among the methods used, multiple linear regression, stepwise regression and the models developed using principal component analysis showed a lower modelling accuracy and validation precision. However, the neural network and random forest methods both achieved a modelling accuracy R2 greater than 0.6, with validation accuracy R2 values of 0.729 and 0.946, respectively. In addition, the random forest method had a lower cross-validation RMSE value, with values of 869.8 kg/hm−2, indicating a higher model accuracy. In summary, the random forest method provided the optimal estimation for wheat yield, enabling the timely and accurate pre-harvest wheat yield prediction, which has significant value for precision agriculture management and decision making. [ABSTRACT FROM AUTHOR]

Risk assessment relies on cost–benefit analysis by prey species in relation to predator behavior. The lunar cycle can have strong influences on the way that predator and prey species behave in their environment as light levels can influence activity patterns. By examining how lunar phase influences behavior, we may be able to better predict instances of human–wildlife conflict. As part of the Elephants and Sustainable Agriculture in Kenya project, over 5 years of study have been dedicated to mitigating human–elephant conflict in the Kasigau Wildlife Corridor in southern Kenya, focusing on the construction of deterrent fences and the collection of environmental data in and bordering the Rukinga Wildlife Sanctuary. Elephant presence around crop fields was hypothesized to have a negative relationship with lunar light levels because of an increase in perceived risk from typically greater human activity with moonlight, and a positive relationship with increased darkness during the waning moon phases. The lunar phase data were compared to elephant presence within 12 m of experimental crop fields along the boundary of their wild habitat and human agricultural land to provide insight for potential crop raiding events. Elephants were present significantly less during the full and gibbous moon phases when compared to the new moon phase, and significantly more during the new and waning moon phases. Our findings are being shared with the farmers living in the KWC and may be useful to others living in high HEC areas by providing a form of early warning system that also may have broader applications in the mitigation of other human–wildlife interactions. HIGHLIGHTS Dynamic landscape of fear provides novel insight on elephant behavior near agricultural lands with applications for conservation strategies. [ABSTRACT FROM AUTHOR]

According to the convergence confinement theory, it is an effective measure to control the large deformation of high ground stress in fractured soft rock tunnels by using yielding support. The yielding support can be classified as either radial or circumferential yielding support. Circumferential yielding support is achieved by transforming radial displacement into circumferential tangential closure without compromising the support capacity of the primary lining support structure. Based on this, and inspired by the design principle of dampers, a yielding support structure system with spring damping elements as its core was developed, based on the connection characteristics of steel arches in highway tunnel, which can provide increasing support resistance in the yielding deformation section. Then the mechanical properties of spring damping elements were obtained through indoor axial pressure and flexural tests. In addition, according to these results with numerical calculations, the yielding support structure system with embedded spring damping elements can reduce the internal force of the support structure by approximately 10% and increase the area of the plastic zone of the surrounding rock by 11.23%, which can fully utilize the self-bearing capacity of surrounding rock and verify the effectiveness of circumferential yielding support. Finally, the spring damping support structure system was designed with reference to the construction process of the tunnel excavated by drilling and blasting method, and the transformation of the spring damping element to spring damping support structure was achieved. Based on field test results, surrounding ground pressure for the yielding support optimization scheme was reduced by 40% and more evenly distributed, resulting in the successful application and a reduction in the construction cost of large deformation tunnels in soft rock. [ABSTRACT FROM AUTHOR]

The study's main aim was to evaluate the effects of complex mineral fertilizers on the complex properties of heavy loam soils in the grey forests of Russia in terms of applying individual soil nutrition components from experiments with fodder beets. This study employed a rigorous and systematic approach to accomplish the defined goal. Specifically, the research was conducted within a seven-field crop rotation system, with fodder beets serving as the primary experimental crop. In addition, a model experiment resembling a vegetation trial was undertaken, incorporating seven distinct schemes involving various types of fertilizers. This design facilitated the evaluation of the effectiveness of each fertilizer type. The study results demonstrate that complex fertilizers impact the soil's chemical and biophysical parameters. Soil acidity decreases through the use of complex, high-nitrogen fertilizers. Major chemical nutrients (nitrogen, phosphorus, and potassium) in plant biomass and soil also have a high degree of transition. It is explained by the effects of combining elements on the destruction intensity of the crystalline lattice in the basic structures of potassium, phosphorus, and nitrogen. There is also evidence that complex fertilizers can improve humus quality and replenish its reserves. All the aforementioned impacts of complex fertilizers on the crop contribute to the high productivity and yield of forage beet. The results of the study may help optimize the fertilization process, improve the quality and quantity of agricultural products, as well as increase soil fertility, and reduce the negative impact of agrochemicals on the environment. [ABSTRACT FROM AUTHOR]

Monitoring of bioinoculants once released into the field remains largely unexplored; thus, more information is required about their survival and interactions after root colonization. Therefore, specific primers were used to perform a long-term tracking to elucidate the effect of Hartmannibacter diazotrophicus on wheat and barley production at two experimental organic agriculture field stations. Three factors were evaluated: organic fertilizer application (with and without), row spacing (15 and 50 cm), and bacterial inoculation (H. diazotrophicus and control without bacteria). Hartmannibacter diazotrophicus was detected by quantitative polymerase chain reaction on the roots (up to 5 × 105 copies g−1 dry weight) until advanced developmental stages under field conditions during two seasons, and mostly in one farm. Correlation analysis showed a significant effect of H. diazotrophicus copy numbers on the yield parameters straw yield (increase of 453 kg ha−1 in wheat compared to the mean) and crude grain protein concentration (increase of 0.30% in wheat and 0.80% in barley compared to the mean). Our findings showed an apparently constant presence of H. diazotrophicus on both wheat and barley roots until 273 and 119 days after seeding, respectively, and its addition and concentration in the roots are associated with higher yields in one crop. [ABSTRACT FROM AUTHOR]

The article explores the concept of agroecology and the importance of integrating different knowledge systems to achieve sustainable nutrient management and climate resilience in agriculture. It emphasizes the value of traditional ecological knowledge and farmer knowledge, alongside Western scientific research, in understanding and managing agroecosystems. The article advocates for collaborative approaches and the inclusion of diverse perspectives to develop effective agroecological practices. It also discusses the potential benefits of ecological approaches to nutrient management, such as enhancing internal nutrient cycling processes and increasing agroecosystem resilience. The article concludes by highlighting the need for an integrated and participatory approach to researching and understanding agroecosystems, which recognizes and respects the contributions of traditional knowledge and Indigenous practices. [Extracted from the article]

The rising adoption of agricultural technologies such as the Internet of Things (IoT) or "smart farming" aims to boost crop production in terms of both quantity and quality. This study compares the benefits of a smart farm employing an IoT-based hydroponic system with those of a conventional hydroponic farm, using Chinese cabbage (Brassica pekinensis L.) as the experimental crop. Our primary objective was to automate environmental monitoring, achieving pH level and electrical conductivity (EC) maintenance through smartphone or computer interfaces for nutrient and acid–base solution adjustments. Additionally, we evaluated plant growth and crop quality, finding superior results with the smart hydroponic system. On average, there were substantial increases in various parameters, including total fresh weight (27.14%), total dry weight (48.90%), plant height (11.14%), stem diameter (32.89%), leaf area (94.30%), leaf width (32.36%), leaf length (38.12%), and chlorophyll content (22.73%). Nitrate accumulation in the edible parts of Chinese cabbage remained within safe limits for both systems, reflecting careful nutrient management. These findings highlight the potential of IoT-based technology in enhancing productivity and quality in hydroponic farming, marking a significant step towards revolutionizing traditional agricultural practices for more efficient crop production systems. [ABSTRACT FROM AUTHOR]

This document is a summary of a special issue of the journal Foods that focuses on pesticide residue monitoring and risk assessment in food. The articles included in this special issue discuss various methods and technologies for detecting and quantifying pesticide residues in different types of food. The studies also assess the health risks associated with pesticide residues in these foods. The findings suggest that while some pesticide residues may be present in food, the overall health risks are low. However, further research is needed to fully understand the dietary risks and ensure the safe use of pesticide-containing products. The article discusses the detection and risk assessment of pesticide residues in food, including the presence of multiple pesticide residues in samples and the development of a quantitative prediction model for pesticide degradation. The authors emphasize the need for refinement of detection methods and the use of multi-methodology and integrated risk assessment approaches. [Extracted from the article]

The ecotoxicological hazard assessment of pesticide use on crops was performed. The study was conducted in 2021-2023 at the experimental field of the Skvyra Research Farm of the Institute of Agroecology and Environmental Management of National Academy of Agrarian Sciences of Ukraine, located in the Forest-Steppe zone of Ukraine. The influence of herbicides, insecticides, and fungicides on the formation of environmental hazards in crop agrocenoses was studied: experiment (1) - peas, winter wheat, buckwheat; experiment (2) - winter wheat, buckwheat, oats. The ecological risk was assessed taking into account the ecotoxic properties of the chemical active ingredients of pesticides. It was found that the main parameters characterizing the occurrence of environmental risks are: (i) the pesticide load, i.e. the amount of toxicant applied per unit of sown area; (ii) the ecotoxicity of the pesticide (LD50), which is established by hygienic standards; (iii) the persistence of the pesticide in the soil, namely, its half-life (DT50), etc. The calculations proved that the pesticides used had a low environmental risk of impact on agrocenoses. This is evidenced by the ecotoxicity index (E). The total pesticide load (ΣE) on the agrocenosis of each crop during the three years of the study (2021-2023) was calculated. It was found that in experiment (1) - ΣExperiment 1 = 0.23 conventional units (c.u.); in experiment (2) - ΣEexperiment 2 = 0.04 c.u. The results obtained indicate an insignificant environmental risk of pesticide use for experimental plots of crops of the studied farm. However, prolonged use of pesticides certainly leads to the concentration of their persistent residues in the soil. This can lead to contamination of crop products and environmental. The cereals (buckwheat and oats) grown on the farm are intended for dietary consumption. To confirm the reliability of the hypothesis of the safety of the obtained grain and cereal products, it is advisable to further study their quality in terms of pesticide residues. It is shown that this methodology can be used to assess the risk of pesticide contamination of an agroecosystem. The ecotoxicity criterion (E) can be considered as a management tool for reducing environmental risks in agroecosystems. [ABSTRACT FROM AUTHOR]

The current study investigates the performance of various sampling designs in providing accurate estimates for crucial maize yield traits (intended for silage) including plant height, fresh/dry/ear weight, number of maize ears per plant, and total ear weight per plant, using spatial maize data. The experiment took place in an experimental field area at Aristotle University (AUTH) farm during the 2016 growing season. Nine sampling designs were statistically analyzed and compared with spatial data from an Italian maize hybrid (AGN720) to identify the most suitable and effective sampling design for dependable maize yield estimates. The study's results indicate that, among the different sampling techniques, Stratified Random Sampling is the most effective and reliable method for obtaining accurate maize yield estimates. This new approach not only provides precise estimates but also requires fewer measurements, making it suitable for experiments where not all plants have emerged. These findings suggest that Stratified Random Sampling can be employed effectively as an alternative to harvesting the entire plot for effectively estimating maize crop traits in experimental plots. [ABSTRACT FROM AUTHOR]

In Romania, evapotranspiration at bare soil or covered by crops is monitored within the experimental evapotranspiration stations: Căldărușani, Voinești and Poiana Brașov. Many experimental researches are carried out, in order to analysed the variation of crop evapotranspiration, in relation to the climatic parameters and soil moisture. The experiments carried out in recent years, have shown that starting from 2021 until 2023, at the level of G1 lysimeters, no more infiltrated water quantities were recorded, so all the amount of water was evaporated. It was also observed that in the year 2022 the sunflower and maize crops did not reach the stage of maturity. In 2023, an experiment was carried out that aimed to compare the maize evapotranspiration in a natural regime and exposed to additional watering (Căldărușani station). The water addition rate was established based on specialized literature and by applying CropWat model. Additional waterings generated different evapotranspiration values. The waterings changed the values of soil moisture and helped the plant not to reach the wilting point before ripening. [ABSTRACT FROM AUTHOR]

The article discusses the demonization and weaponization of conventional agriculture in recent years, as well as the promotion of radical agricultural transformation. It emphasizes the need for improvements in current agricultural practices through science-based technologies, such as improved crop varieties, soil management strategies, and strategies to reduce greenhouse gas emissions. The article also examines two claims that have been used to support radical agricultural transformation: the loss of plant genetic diversity and the contribution of smallholder farmers to global food production. It questions the validity of these claims and highlights the potential for misleading policy decisions based on questionable estimates. The article concludes by emphasizing the importance of evidence-led policies for sustainable food production. [Extracted from the article]

The demand for soybeans as one of cereal commodities increases every year, however, to meet the production and demand level is still challenging in Indonesia. One of the causes of low soybean production is stress during cultivation, lack of nutrients, or poor quality of soybean seeds. One solution is to increase seed protection by coating the seeds with an environmentally friendly biological seed coating. This study aims to obtain the best biological seed coating for increasing soybean seed viability, vigor, and yield. The research was conducted at the Faculty of Agriculture Experimental Station of Universitas Padjadjaran, Jatinangor from August to November 2021. Two sets of experimental design were employed in this study, a Completely Randomized Design for the viability and vigor parameters in laboratory, and a Randomized Block Design with four replications for evaluation of the yield components in the field. The experiment was carried out with a combination of soybean cultivar and biological seed coating. The cultivars used in this study were Anjasmoro cv. (yellow) and Detam-4 cv. (black) and the biological seed coatings were B. subtilis, Trichoderma sp., and Rhizobium sp. Post-hoc test after F-test used Least Significance Different (LSD) with a significant level of 5%. The results showed that the application of the three biological seed coatings was not significantly affect seed physiological traits. However, the seed coating treatments increased the number of seeds per plant and seed weight per plant in yellow soybeans. Meanwhile, the application of B. subtilis and Rhizobium sp. in black soybeans increased the number of seeds per plant and the weight of seeds per plant. The best biological seed coating in this experiment was B. subtilis. [ABSTRACT FROM AUTHOR]

One of the latest environmentally friendly methods in soybean production technology is the pulsed electromagnetic field of low frequencies (PEMP). The paper presents the results of the influence of electromagnetic stimulation of soybean seeds on grain yield, protein and oil yield, depending on different agroclimatic conditions, exposure time and frequency. In the 2012-2017 research period, the soybean cv. Valjevka was used in the Institute of Field and Vegetable Agriculture experimental field, Novi Sad, Serbia. Immediately before sowing, the seeds were subjected to PEMP treatment, with a pulse generator and a tape applicator, in the following variants: electromagnetic field frequencies of 16, 24 and 30 Hz, and exposure time of 0, 30 and 60 min. The most successful variant of seed stimulation for all three examined parameters was at 16 Hz and 30 min, where the research results show that this measure can increase the examined parameters by more than 10%. The average yield of grain for all years of research with seed stimulation was 4.85% (3 338 kg/ha) compared to the control (3 203 kg/ha). The average grain protein yield in the treatments with PEMP was 1 315 kg/ha, which was 4.26% higher compared to the variant without PEMP (1 260 kg/ha), and the treatment was 4% higher in the average oil yield, 703 kg/ha compared to the control 676 kg/ha. Also, the analysis of the mutual dependence of the indicators is in a positive correlation, which is essential for plant breeding and the development of new technologies, which have economic justification, are safe for use and have a positive impact on adverse effects such as drought. [ABSTRACT FROM AUTHOR]

Drought and climate change have decreased water availability for agriculture, especially in the desert of southwestern USA. Efficiency enhancements in irrigation management aimed at conserving water are key to adjust to limits in water supply, improve profitability and sustainability of alfalfa production in arid and semiarid areas. This study intended to conduct a field-scale analysis to develop yield and ET estimation tools for the effective use of irrigation water in a desert alfalfa production system. Extensive data collection and trials were carried out over three years in nine fully irrigated commercial alfalfa fields in the low deserts of California. The seasonal crop water consumption measured using the residual of energy balance method varied from 1381 mm to 1596 mm across the experimental sites and crop seasons. Variable seasonal dry mater (DM) yields ranged from 23.01 Mg ha−1 to 29.90 Mg ha−1. The results indicated that the first five cuttings each year were the most productive cuttings with a mean DM value ranged between 3.29 (cut 1) and 4.21 (cut 4) Mg ha−1 but declined in later cuttings. An average annual water productivity (WP) value of 17.0 kg ha−1 mm−1 was determined across the sites varying from 15.5 to 18.9 kg ha−1 mm−1. The findings suggested that one may lose up to 1.44 Mg ha−1 alfalfa yields with moderate summer deficit irrigation strategies, using 40% less water applied than full irrigation practices over the summer period of July–September. A more severe summer water deficit, with no irrigation event over the summer period of July–September may result in a potential water savings of 0.234–0.246 (ha·m) ha−1 and 19–21% seasonal yield losses in the desert environment. This study describes the seasonal yield pattern, the crop water use-production function, and the crop coefficient values for various harvest cycles over the crop season. These tools may assist farmers to quantify water savings and estimate yield losses for more accurate and effective irrigation management strategies to meet water conservation objectives and for the resiliency of alfalfa production in the desert region. [ABSTRACT FROM AUTHOR]

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An important direction of modern agrotechnologies of crop production is the greening of intensive technologies and energy conservation, this contributes to the use of biological preparations that can increase yields, improve grain quality, increase profitability by saving mineral fertilizers and protective equipment. Therefore, field experiment was conducted during 2019-2021 in the dry-steppe zone of chestnut soils of the Volgograd region. The scheme of the experiment included four sites with late-autumn; early-spring; late-spring application dates and control, without the use of nitrogen fertilizers. All records and surveys were carried out according to the methodology of the state variety testing of agricultural crops: calculation of germination, determination of tillering coefficient, determination of the weight of aboveground biomass of plants, the density of productive stems. As a result of studying the issue conducted in various weather conditions of the test years, it was established that the period of application of nitrogen fertilizers had a significant impact on the growth, development and yield of experimental crops. The highest yield indicators were recorded at the time of early spring application of nitrogen fertilizers @ 38.0, 30.8 and 40.2 q/ha in 2020, 2021 and 2022, respectively. With the delay in the application of nitrogen fertilizers in the spring, the yield decreased by 8-13% during the observation period, and 32.94 28.2 and 35.8 q/ha in 2020, 2021 and 2022, respectively. The introduction of nitrogen fertilizers in autumn, as close as possible to the end of the growing season, led to a decrease in yield by only 2-4% and amounted to 36.5, 29.8 and 39.5 q/ha in 2020, 2021 and 2022, respectively. [ABSTRACT FROM AUTHOR]

Copyright of INMATEH - Agricultural Engineering is the property of INMATEH - Agricultural Engineering 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.)

Plant loss occasionally occurs in field experiments with coffee crops in experimental plots. In breeding programs, such loss can be harmful, especially when the corresponding statistical analyses are not consistent with the experimentally generated data. Herein, we analyzed productivity data to determine whether the compensatory effect occurs in coffee crops, evaluated the need to correct experimental failures, and identified the best stand correction method. We used productivity data from six harvests of eleven experiments with Coffea arabica plants. The experiments were implemented in a randomized block design, with four replications and six plants per plot. The following stand correction methods were evaluated: rule of three; Zuber; Vencovsky and Cruz covariance of the average or ideal stands; and Cruz, and the data were compared without correction adjustments. The most adequate correction methods were selected based on genetic variance, selective accuracy, and progeny ordering. The compensatory effect was evident from the analyzed data, with stand correction being evidenced as beneficial in progeny competition experiments. The best results were obtained for the covariance methods using average or ideal stands, followed by the method proposed by Cruz. The rule of three and Zuber method exhibited unsatisfactory results and are not recommended for stand correction in progeny competition experiments with coffee crops. [ABSTRACT FROM AUTHOR]

Copyright of Iraqi Journal of Agricultural Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) 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.)

Until recently, mouldboard ploughing was used as the main tillage in almost the entire territory of Ukraine and Russia. However, mouldboard technologies contribute to the formation of a "plough pan", which contributes to additional soil compaction. The intensity of agricultural production exacerbated the problem of soil compaction by machine and tractor units. The over-consolidation of soil results in stunted plant root growth, lack of oxygen, and water and nutrient restrictions. Soil compaction can be reduced by deep local chiselling. The aim of the study was to determine the density of the soil at different depths during continuous traditional cultivation (reverse ploughing). The density of the soil was evaluated by resistance to penetration into the soil in a vegetable-forage crop rotation on an experimental field with continuous traditional tillage. The measurement of penetration resistance was carried out using an automatic electronic hardness tester "DATAFIELD". The boundaries of the experimental field were determined, a computer map of the experimental field was compiled with automatic "grid" of plot sizes, two-dimensional mapping was carried out, and the sequence and place of measurements were developed. As a result, the level of soil compaction at different penetration depths and resistance to root growth was determined. It has been established that with constant traditional reverse tillage, the soil at a depth of more than 10 cm is sufficiently compacted. At a depth of 15 cm, a strong compaction of the soil is observed, which indicates its physical and hydrological degradation. [ABSTRACT FROM AUTHOR]

Drought severely damages crop production, even under conditions so mild that the leaves show no signs of wilting. However, it is unclear how field-grown plants respond to mild drought. Here, we show through six years of field trials that ridges are a useful experimental tool to mimic mild drought stress in the field. Mild drought reduces inorganic phosphate levels in the leaves to activate the phosphate starvation response (PSR) in soybean plants in the field. Using Arabidopsis thaliana and its mutant plants grown in pots under controlled environments, we demonstrate that PSR occurs before abscisic acid response under progressive mild drought and that PSR plays a crucial role in plant growth under mild drought. Our observations in the field and laboratory using model crop and experimental plants provide insight into the molecular response to mild drought in field-grown plants and the relationship between nutrition and drought stress response. Even mild drought impacts crop production significantly. Here, the authors develop an experimental mild drought system induced by ridges in the field and find that phosphate starvation response occurs before ABA response in early mild drought. [ABSTRACT FROM AUTHOR]

Crop characterization is considered a prerequisite to devising effective strategies for ensuring successful implementation of sustainable agricultural management strategies. As such, remote-sensing technology has opened an exciting horizon for crop characterization at reasonable spatial, spectral, and temporal scales. However, the presence of shadows on croplands tends to distort radiometric properties of the crops, subsequently limiting the retrieval of crop-related information. This study proposes a simple and reliable approach for radiometrically compensating crops under total occlusion using brightness-based compensation and thresholding approaches. Unmanned aerial vehicle (UAV) imagery was used to characterize crops at the experimental site. In this study, shadow was demarcated through the computation and use of mean spectral radiance values as the threshold across spectral channels of UAV imagery. Several image classifiers, viz., k-nearest neighbor (KNN), maximum likelihood, multilayer perceptron (MLP), and image segmentation, were used to categorize land features, with a view to determine the areal coverage of crops prior to the radiometric compensation process. Radiometric compensation was then performed to restore radiometric properties of land features under occlusion by performing brightness tuning on the RGB imagery. Radiometric compensation results revealed maize and soil as land features subjected to occlusion. The relative error of the mean results for radiance comparison between lit and occluded regions revealed 26.47% deviation of the restored radiance of occluded maize from that of lit maize. On the other hand, the reasonable REM value of soil was noted to be 50.92%, implying poor radiometric compensation results. Postradiometric compensation classification results revealed increases in the areal coverage of maize cultivars and soil by 40.56% and 12.37%, respectively, after being radiometrically compensated, as predicted by the KNN classifier. The maximum likelihood, MLP, and segmentation classifiers predicted increases in area covered with maize of 18.03%, 22.42%, and 30.64%, respectively. Moreover, these classifiers also predicted increases in the area covered with soil of 1.46%, 10.05%, and 14.29%, respectively. The results of this study highlight the significance of brightness tuning and thresholding approaches in radiometrically compensating occluded crops. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate whether, in the context of a higher incidence of Ustilago maydis and Fusarium spp. at optimal and delayed harvest times, a higher incidence of mycotoxin contamination in maize grains could be expected. The field experiment was carried out at the Lithuanian Research Centre for Agriculture and Forestry experimental fields over three consecutive years (2020–2022). Two maize hybrids (Duxxbury and Lapriora) with different FAO numbers were used. The experimental design in the field was a randomized complete block design. Harvesting took place at three different times: first at physiological maturity, and then 10 (±2) and 20 (±2) days after the first harvest. Each hybrid had four repetitions at different harvest times. The U. maydis infection was only detected in 2021 and after the first harvest cobs were further divided into four different groups with four repetitions: healthy cobs, cobs visually infected with Fusarium spp., cobs visually infected with common smut, and cobs visually infected with both pathogens. No U. maydis-damaged maize cobs were found in 2020 and 2022. The levels of Fusarium microscopic fungi in maize grains were also from 4 to 16 times higher in 2021 than in 2020 and 2022. Harvest delays in 2020 led to a significant deoxynivalenol concentration increase in the Duxxbury hybrid and an HT-2 concentration increase in the Lapriora hybrid. In 2021, deoxynivalenol, 3-acetyl-deoxynivalenol, 15-acetyl-deoxynivalenol, and HT-2 concentrations significantly rose in both hybrids, but the T-2 concentration significantly increased only in the Lapriora hybrid. Deoxynivalenol concentrations were, respectively, 110 and 14.6 times higher than in cobs only infected with Fusarium spp. or U. maydis. Concentrations of 15-acetyl-deoxynivalenol were, respectively, 60, 67, and 43 times higher than in asymptomatic cobs and cobs only infected with Fusarium spp. or U. maydis. Cobs contaminated with both pathogens also had higher concentrations of 3-acetyl-deoxynivalenol. T-2 and HT-2 were detected in maize grains harvested from cobs infected only with Fusarium spp. The presence of U. maydis and Fusarium fungi in maize cobs, along with harvest delays, led to significant increases in mycotoxin concentrations, highlighting the importance of timely harvesting and pathogen management to mitigate mycotoxin contamination in maize grains. [ABSTRACT FROM AUTHOR]

Copyright of Zagazig Journal of Agricultural Research is the property of Egyptian National Agricultural Library (ENAL) 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.)

Against the backdrop of excessive global nitrogen fertilizer use, the loss of nitrogen fertilizer has led to environmental pollution and resource waste. Therefore, finding effective mitigation measures is of great significance for sustainable agricultural development. This study examined the problems of nitrogen fertilizer loss in soil and the potentials of nitrification inhibitors and urease inhibitors to reduce it by using quantitative analysis methods. Different soil types and treatment areas at the ecological agriculture experimental station were included in the study with different ratios of nitrification inhibitor, 3,4-Dimethylpyrazole phosphate (DMPP), and urease inhibitor, N- (n-butyl) thiophosphoric triamide (NBPT) treatments. The indicators for the degree of nitrogen fertilizer loss measurement included ammonia volatilization, nitrogen leaching, and nitrogen fertilizer utilization efficiency. The results showed that, by using the CO (NH2)2+DMPP+NBPT treatment method, the cumulative losses of ammonia volatilization in sandy soil and clay soil after 15 days were 5,430.36 g N/hm² and 4,130.36 g N/hm², respectively. The nitrogen runoff loss rates were approximately 36-60% and 34-45%, respectively. The nitrogen leaching loss rates were about 20-74% and 15-50%, respectively. The nitrogen fertilizer utilization efficiency for wheat was approximately 36.1-37.4% and 44.3-45.6%, respectively. The results indicated that the utilization of nitrification/urease inhibitors could significantly reduce nitrogen fertilizer loss and improve its overall utilization efficiency. The results of this study offered valuable insights for enhancing environmental conservation and promoting food security. [ABSTRACT FROM AUTHOR]

Top‐down suppression of herbivores is a fundamental ecological process and a critical service in agricultural landscapes. Adoption of bioenergy cropping systems is likely to become an increasingly important driver causing loss or gain of this service in coming decades. We measured natural pest suppression potential in ten model bioenergy crops in a long‐term experimental array by deploying plasticine sentinel caterpillar mimics, which record imprints from predator attacks. Cropping systems included three intensive annual row crop systems and a range of simple perennial monocultures and more complex polycultures. We compared attack rates across the ten cropping systems and assessed differences over time within a growing season and between the ground level and canopy. We found strong differences in attack rates across cropping systems, usually with more attacks in perennial crops than annuals. However, outcomes varied in space and time, both within and among cropping systems. Birds and small mammals were responsible for most, and sometimes all, attacks in annual crops and were most important early in the season. Chewing arthropod attacks increased over the course of the growing season and were responsible for most attack events in perennial systems. In late summer there were almost no attacks in annual crop canopies, while attack rates in perennial canopies at the same time were quite high and were carried out almost entirely by chewing arthropods. Our results underscore the lack of trophic complexity in annual bioenergy cropping systems relative to perennials. They also illustrate the dramatic changes in predator activity and predation intensity that occur both seasonally and between the ground and plant canopy. Policies and practices that increase the footprint of annual crops for bioenergy are likely to cause a deficit in pest suppression services at local and landscape scales. [ABSTRACT FROM AUTHOR]

This study introduces a dataset of crop imagery captured during the 2022 growing season in the Eastern Kazakhstan region. The images were acquired using a multispectral camera mounted on an unmanned aerial vehicle (DJI Phantom 4). The agricultural land, encompassing 27 hectares and cultivated with wheat, barley, and soybean, was subjected to five aerial multispectral photography sessions throughout the growing season. This facilitated thorough monitoring of the most important phenological stages of crop development in the experimental design, which consisted of 27 plots, each covering one hectare. The collected imagery underwent enhancement and expansion, integrating a sixth band that embodies the normalized difference vegetation index (NDVI) values in conjunction with the original five multispectral bands (Blue, Green, Red, Red Edge, and Near Infrared Red). This amplification enables a more effective evaluation of vegetation health and growth, rendering the enriched dataset a valuable resource for the progression and validation of crop monitoring and yield prediction models, as well as for the exploration of precision agriculture methodologies. Dataset: https://doi.org/10.5281/zenodo.7749239 , https://doi.org/10.5281/zenodo.7749362 , https://doi.org/10.5281/zenodo.7748792 , https://zenodo.org/record/7860751. Dataset License: Creative Commons Attribution 4.0 International [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Oil Crop Sciences is the property of Oil Crops Research Institute of Chinese Academy of Agricultural Sciences 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.)

Our experiments with crop progenitors have demonstrated that these species exhibit dramatic plasticity in key traits that are affected by domestication, including seed and fruit morphology. These traits can be altered by cultivating crop progenitors for a single season, in the absence of any selection for domesticated phenotypes. We hypothesize that cultivation caused environmental shifts that led to immediate phenotypic changes in crop progenitors via developmental plasticity, similar to tameness in animals. Here we focus on the loss or reduction of germination inhibitors in an annual seed crop because seeds with high dormancy are undesirable in crops, and also present a serious barrier to selective pressures that arise from seed-saving and planting by humans. Data from four seasons of observation of the crop progenitor Polygonum erectum L. suggest that the low plant density conditions of an agroecosystem trigger a phenotypic response that reduces germination inhibitors, eliminating a key barrier to further selection. The timing of the harvest can also be used to manipulate the germinability of seed stock. These observations suggest that genetic assimilation may have played a role in the domestication of this plant. More experimental work with crop progenitors is needed to understand whether or not this phenomenon played a part in the domestication of other plants, and to accurately interpret the significance of ancient plant phenotypes in the archaeological record. [ABSTRACT FROM AUTHOR]

For efficient grain production in arid climate, producers need a choice of winter crop varieties. For this purpose, an ecological test of varieties of winter wheat and winter barley was carried out on experimental fields typical for the climatic conditions of the Lower Volga region of Russia. Plots with experimental crops, with an area of 10 m2, were located by the method of successive repetitions in 3-fold repetition. By the ecological test, varieties of winter crops of various originators were sown, according to the predecessor - black fallow, with seeds with a field germination rate of 90-95%, with a seeding rate of 3.5 million pcs. ha, to a depth of 5-6 cm. There were 16 varieties of winter wheat in the test, Don 93 served as the standard variety. Five varieties of winter barley were tested, the standard variety was Volzhsky 1. The obtained results of the yield of varieties were processed by analysis of variance to assess their yield. It has been established that in the technological process of production of grain of winter crops, the value of the variety is significant and has a share of 72.4%, the remaining factors of production account for 27.5%. The leader in terms of winter wheat yield (8.5 t/ha) was the Tarasovskaya variety. The lowest yield in the test was in the Governor of the Don variety 5.7 t/ha. High yield of winter wheat in the variety of local selection Kamyshanka 3 was 8.1 t/ha. The maximum biological yield of 6.4 t/ha was obtained for the winter barley variety Buran, mainly due to the larger number of productive shoots 440 pcs/m² and the largest grain mass per spike 1.46 g variety Voskhod 4.9 t/ha. [ABSTRACT FROM AUTHOR]

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Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering 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 Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office 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.)

Wheat can be cultivated by hole sowing, but its border effect has not yet been studied. Therefore, we carried out a field experiment from 2021 to 2022 at the Doukou Crop Experimental Demonstration Station (108°52′ E, 34°37′ N) of Northwest A&F University in Jingyang County, Xianyang City, Shaanxi Province, China. The response of dry matter, photosynthetic characteristics, and yield components of wheat to the border effects under the hole sowing method was studied. The results showed specific border effects on each index of five wheat varieties (XN136, XN175, XN527, XN536, and XN765), among which the border effects of XN175 and XN765 were the most significant, with the highest yield. Subsequent correlation analysis revealed that only grain per spike and intercellular carbon dioxide concentration responded negatively to the border effects, and the rest were positively correlated. Finally, we conducted a random forest model analysis of different indicators of wheat varieties with significant border effects. We found that net photosynthetic rate and aboveground dry matter per plant had the most significant impact and contribution to the border effects. In contrast, grain per spike had the most negligible impact on the border effects. Our results fill a gap in the study of the border effects of wheat under hole sowing cultivation for future researchers. [ABSTRACT FROM AUTHOR]

For seed germination and the formation of a good soybean crop, significant reserves of soil moisture are required, which depends on the autumn-winter soil preparation, weather conditions and planting dates. The purpose of this study is to identify the impact of the main tillage technology on its agrophysical properties and conditions for the growth and development of soybean plants. Experimental crop rotation: soybean – winter wheat was carried out under favourable (hydrothermal coefficient 1.46) and dry (hydrothermal coefficient 0.66–0.87) weather conditions. The main tillage was carried out with a stratifier PRSM-5 to a depth of 15–17 cm or a chisel plough PCh-2.5 to a depth of 25–27 cm, with additional pre-sowing or post-sowing rolling with a ring-spur roller KKSH. Sowing was carried out at a depth of 10 cm with stable heating of the soil in three periods: the first at 8–10 °С, the second at 10–12 °С, and the third at 12–14 °С. As a result of evaluating the influence of various factors, it was found that under favourable conditions, the highest seed productivity of soybean plants (1.91–1.96 t·ha−1) was formed after treatment with the stratifier PRSM-5 at the first sowing period and at the second sowing period after chisel ploughing with additional soil compaction. In dry weather conditions, pre-sowing treatment with a stratifier PRSM-5 had an advantage in seed productivity by 7–12% compared to ploughing with a chisel plough PCH-2.5. [ABSTRACT FROM AUTHOR]

Genetically engineered (GE) crops are likely to be one solution when it comes to balancing the needs of a growing human population and changing climate. Recent data suggest that many U.S. adults believe that GE foods are risky for human health and the environment, despite scientific consensus that they are no more harmful to human health or the environment than conventionally bred crops. While some evidence suggests that consensus messaging could be a significant factor in publics' perceptions about technologies like GE, the effect of communicating scientific consensus and under different conditions remains unclear. We test message effectiveness in terms of individuals' consensus perceptions and beliefs about the environmental risks and benefits of GE technology. We find that consensus messaging reduces perceived environmental risks of GE crops, and that supplementing a consensus message with benefits information reduces perceived environmental risks and increases anticipated benefits. We find an interaction effect for trust in scientists, such that those who have lower trust in industry scientists exhibit a backfire effect when exposed to consensus information. [ABSTRACT FROM AUTHOR]

Cover crops are gaining traction in many agricultural regions, partly driven by increased public subsidies and by private markets for ecosystem services. These payments are motivated by environmental benefits, including improved soil health, reduced erosion, and increased soil organic carbon. However, previous work based on experimental plots or crop modeling indicates cover crops may reduce crop yields. It remains unclear, though, how recent cover crop adoption has affected productivity in commercial agricultural systems. Here we perform the first large‐scale, field‐level analysis of observed yield impacts from cover cropping as implemented across the US Corn Belt. We use validated satellite data products at sub‐field scales to analyze maize and soybean yield outcomes for over 90,000 fields in 2019–2020. Because we lack data on cover crop species or timing, we seek to quantify the yield impacts of cover cropping as currently practiced in aggregate. Using causal forests analysis, we estimate an average maize yield loss of 5.5% on fields where cover crops were used for 3 or more years, compared with fields that did not adopt cover cropping. Maize yield losses were larger on fields with better soil ratings, cooler mid‐season temperatures, and lower spring rainfall. For soybeans, average yield losses were 3.5%, with larger impacts on fields with warmer June temperatures, lower spring and late‐season rainfall, and, to a lesser extent, better soils. Estimated impacts are consistent with multiple mechanisms indicated by experimental and simulation‐based studies, including the effects of cover crops on nitrogen dynamics, water consumption, and soil oxygen depletion. Our results suggest a need to improve cover crop management to reduce yield penalties, and a potential need to target subsidies based on likely yield impacts. Ultimately, avoiding substantial yield penalties is important for realizing widespread adoption and associated benefits for water quality, erosion, soil carbon, and greenhouse gas emissions. [ABSTRACT FROM AUTHOR]

Leaf airborne diseases cause major shortfalls in agricultural crops. The introduction of technical means can significantly improve early-warning systems for plant diseases as well as provide timely and accurate forecasts. In this paper, we aim to evaluate the possibilities of detecting a phytopathogenic infection using a spore-catching device developed at the Federal Research Center of Biological Plant Protection (FRCBPP) on winter wheat varieties of different levels of susceptibility to major economically important leaf diseases, taking into account climatic conditions. The device captures spores in the surface layer of air among crop plants. We conducted research in the experimental fields of FRCBPP in 2019–2021. The objects of the study were four cultivars of winter wheat. They were selected according to the degree of resistance to various leaf diseases. We studied the progress of wheat diseases according to generally accepted international scales the onset of the first manifestations to their maximum development. We studied the aerogenic infection in wheat crops using the FRCBPP developed portable device for determining the infestation of plants. Sampling was carried out in the same period as the visual assessment. The samples were taken in the crops of each variety at five points. The sampling time was one minute. As a result of research on experimental crops of four varieties of winter wheat, we observed the development of such diseases as powdery mildew (Erysiphe graminis), yellow spot (Pyrenophora tritici-repentis), septoria leaf spot (Septoria tritici), yellow (Puccinia striiformis) and brown rust (Puccinia triticina). In a laboratory study of samples under a light microscope, all of the listed pathogens were found except for septoria leaf spot. Two-way analysis of variance confirmed the statistically significant separate and cumulative influence of the cultivar and year factor on winter wheat diseases. A generalized correlation analysis for three growing seasons (2019–2021) showed that an average statistically significant correlation coefficient (0.5–0.6) remains for the total groups for powdery mildew, yellow and brown rust. This indicator for the causative agent of yellow spot was equal to 0.4 with a high level of statistical significance. Thus, we conclude that by using a spore-catching device, it is possible to identify spores of economically significant pathogens in winter wheat crops and predict the further development of pathogens, taking into account the cultivar and annual climate factors. [ABSTRACT FROM AUTHOR]

Errors in the generation of production maps can arise from many causes and are practically inevitable. Even though errors will occur, production data can be improved by following a few best practices. The primary methods for improving harvest data should always be the calibration and proper operation of the combine. In cases where this is not possible or where errors occur, the John Deere Operations Center offers data analysis tools through filtering, postcalibration, and improving the visualization of production maps. These practices will result in obtaining accurate data on which agronomic decisions can be made for subsequent farming years. Mapping productions using the John Deere S780i harvester combine and its associated systems provides the farmer with valuable information about their farm, which can be used to make informed and calculated decisions to increase overall productivity, sustainability, and profitability of the agricultural farm. [ABSTRACT FROM AUTHOR]

It is also important to indicate the presence of wild or weed plant species; I Amaranthus hybridus i , I Chenopodium album i , I Chenopodium murale i , I Chenopodium vulvaria i , belonging to the Chenopodiaceae (Amaratnaceae) family that is naturally present in the region (Deghiche-Diab et al., 2016; Deghiche-Diab & Deghiche, 2016). First record of the sawfly Athalia cornubiae Benson, 1931 (Hymenoptera: Tenthredinidae) in the oasis of Ziban (Algerian Sahara) Athalia cornubiae Benson (Hymenoptera: Tenthredinidae: Allantinae), A sawfly genus and species new to North America. Notes on the British sawflies of the genus Athalia (Hymenoptera: Tenthredinidae), with the description of a new species. [Extracted from the article]

Crop disease leaf image segmentation (CDLIS) is the premise of disease detection, disease type recognition and disease degree evaluation. Various convolutional neural networks (CNN) and their modified models have been provided for CDLIS, but their training time is very long. Aiming at the low segmentation accuracy of various diseased leaf images caused by different sizes, colors, shapes, blurred speckle edges and complex backgrounds of traditional U-Net, a lightweight multi-scale extended U-Net (LWMSDU-Net) is constructed for CDLIS. It is composed of encoding and decoding sub-networks. Encoding the sub-network adopts multi-scale extended convolution, the decoding sub-network adopts a deconvolution model, and the residual connection between the encoding module and the corresponding decoding module is employed to fuse the shallow features and deep features of the input image. Compared with the classical U-Net and multi-scale U-Net, the number of layers of LWMSDU-Net is decreased by 1 with a small number of the trainable parameters and less computational complexity, and the skip connection of U-Net is replaced by the residual path (Respath) to connect the encoder and decoder before concatenating. Experimental results on a crop disease leaf image dataset demonstrate that the proposed method can effectively segment crop disease leaf images with an accuracy of 92.17%. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Irrigation & Drainage is the property of Journal of Irrigation & Drainage Editorial Office 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.)