Crop Plots Research Articles

When are you measuring soil β‐glucosidase activities in cropping systems?

AbstractIn situ soil respiration is driven by annual patterns of temperature and soil moisture, but what about extracellular enzyme activities responsible for depolymerizing soil organic matter? We conducted biweekly measurements of potential soil β‐glucosidase activities during a 4‐month period from March soil thawing through July in annually cropped field plots in eastern South Dakota. Our objective was to determine the best sampling time to resolve the effects of crop rotational diversity on soil microbial activities. Potential β‐glucosidase activities were elevated immediately following soil thaw, peaked in May, and declined to their lowest value in mid‐summer. Temperature and precipitation had no value in predicting enzyme activities; however, enzyme activities were affected by crop rotational diversity and responded to current crop and previous crop. These findings are pertinent to the use of soil extracellular enzymes in soil health assessments and as indicators of microbial substrate preference with implications for soil carbon stabilization.

Does a native and introduced cover crop species differ in their ability to suppress weeds? A study in a table grape vineyard

This study compared the weed suppression ability of a native cover crop species phacelia (Phacelia tanacetifolia), an introduced cover crop species rye (Secale cereale L.), and a no cover crop (herbicide‑managed) system in a vineyard. Cover crops were sown in the interrow spaces of the grapevine rows. Percent weed cover after the cover crop termination was lower in the interrow of the phacelia than the no cover crop plots. During the cover crop growing season, phacelia suppressed weeds more than rye. However, the weed seedbank of the cover crop plots was greater than that of the no cover crop plots.

Agricultural Valorization of Treated Effluent from Korhogo Wastewater Treatment Plant

Aims: The main objective is to evaluate the effluents of Korhogo’s wastewater treatment plant for irrigation and fertilization in agriculture. Study Design: Characterization of outlet treated wastewaters has been firstly done. Then their suitability for irrigation has been determined and finally their fertilizing power has been assessed. Place and Duration of Study: Department of geosciences, Korhogo’s wastewater treatment plant and laboratory. Sampling and analyses were carried out in January 2023, before agricultural field implementation started in February 2023. Methodology: Firstly, Physico-chemical and microbiological analyses, allowed characterization of outlet treated wastewaters. A determination of their suitability for irrigation was then done through Sodium Adsorption Ratio calculation and water classification with Diagram of Richards. An assessment of their fertilizing capacity was finally carried out using these waters for irrigating and fertilizing crop plots (3x2 m), and consisting of determining firstly their biodegradability index, then their nutrient contents (Nitrogen, Phosphorus and potassium), and the influence of their use on crop development and yield. Results: The results show that several parameters meet standards for discharge of treated wastewater except total nitrogen, suspended matters and total phosphorus (67.67 mg/l, 271.33 mg/l and 18.30 mg/l). Sodium Adsorption Ratio (SAR) value=3.78 and C3S1 class indicate that these treated effluents can be used for irrigation without salinization risk. As fertilizer, treated effluents brought to crops respectively 603 kg/ha of nitrogen, 162 kg/ha of phosphorus and 99 kg/ha of potassium for maize; and 368.5 kg/ha of nitrogen, 99 kg/ha of phosphorus and 60.5 kg/ha of potassium respectively for Okra. A yield of 12.2 kg of fresh maize and 3.15 kg of fresh okra was obtained for the plot irrigated by treated effluents, compared with 4.80 kg of fresh maize and 0.36 kg of fresh okra for the plot irrigated by well water. Conclusion: This study has shown that outlet treated wastewater from Korhogo’s wastewater treatment plant is suitable for crops irrigation, contains sufficient nutrients enhancing crops development and yield.

Long‐term tillage and cover cropping differentially influenced soil nitrous oxide emissions from cotton cropping system

AbstractClimate‐smart agricultural practices, such as no‐tillage (NT) and cover cropping, have been widely adopted and are anticipated to yield multiple benefits, including soil carbon sequestration, enhancing soil health, and crop yield stability. However, their influence on nitrous oxide (N2O) emissions varies, with the potential of both increasing and decreasing N2O emissions. Increasing N2O emissions under these practices may potentially offset the climate mitigation benefits from increased soil carbon sequestration. We investigated N2O emissions in response to 42 years of long‐term adoption of NT and legume cover crop, under nitrogen (N) rates of 0 and 67 kg N ha−1, in a continuous cotton system in the Southeastern United States. Intensive manual chamber‐based measurements were conducted over two growing seasons (2021–2022 and 2022–2023). Long‐term NT did not significantly affect cumulative N2O emissions during the study period (p > 0.05). Hairy vetch cover crop‐grown plots emitted two to three times more N2O than those without cover crops in 2021–2022, with no significant effect observed in 2022–2023. Cumulative emissions in cover crop plots were greater compared to those in no cover crop plots when fertilized with 67 kg N ha−1 in 2021–2022; however, this trend did not persist in 2022–2023. While interannual variability exists, our results generally suggest that long‐term NT may not increase N2O emissions, hence its adoption could enhance its broader soil health and climate benefits via soil carbon sequestration, whereas managing legume cover crop residues in N‐fertilized systems is critical to mitigate N2O emissions.

Analyzing the spatiotemporal habitat colonization dynamics of the common vole (Microtus arvalis Pallas) in Castilla y León, northwest Spain, using a hotspot-based approach†.

The common vole is an agricultural pest and population outbreaks have caused significant crop damage in the agricultural areas of the west-central part of the Iberian Peninsula (Spain) during the last few decades. Thus, monitoring is imperative to gain a comprehensive insight on its spatiotemporal habitat colonization dynamics. This work was performed on a long-term database with the primary objective of establishing an operational framework for understanding the spatial and temporal distribution of the common vole, all of it based on the Getis-Ord statistics. The temporal evolution of the vole abundance index (VAI) was consistent for the three studied habitats, that is, crops, reservoirs and paths. Furthermore, the majority of common vole abundance peaks coincide with summer periods, especially in annual herbaceous crops. The spatial distribution of vole abundance exhibited a non-random pattern, characterized by spatial clustering. Particularly, the areas with higher significance of this clustering were located at the so-called 'Tierra de Campos' county, covering northern Valladolid, southern Palencia and north-eastern Zamora provinces. Periods of major incidence and concentration were 2013-2014, 2016-2017 and 2019. Common vole temporal occupancy patterns demonstrate that colonization occurred simultaneously in alfalfa reservoirs and dispersion paths, both preceding settlement in annual herbaceous crop plots. The geographic information system (GIS)-hotspots-based methodology proposed here can be valuable for stakeholders involved in integrated management of the common vole, serving as a detector of pest-prone areas in both space and time. These hotspots are useful for predicting future surveillance areas that accurately reflect pest colonization patterns. It was found that common vole abundance along dispersal paths acts as a source of dissemination, preceding the risk of colonization in annual herbaceous crop plots. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Summer cover crop and temporary legume-cereal intercrop effects on soil microbial indicators, soil water and cash crop yields in a semi-arid environment

ContextFew studies have investigated summer cover crops as a replacement for bare fallow in semi-arid temperate regions, and summer cover crop impacts on soil biological function, water balances and subsequent winter crop yields in these regions remain largely unknown. ObjectiveThe 4-year field study aimed to determine the consequences of replacing a summer fallow with a summer growing cover crop on soil function, water balances and subsequent winter cash crop yields in a semi-arid region (486 mm mean annual rainfall) of the Australian southern cropping zone. MethodsA canola (Brassica napus)-wheat (Triticum aestivum L.) rotation with summer fallow was compared to the same rotation with either i) a single species (buckwheat, Fagopyrum esculentum L.) summer cover crop; ii) a four-species mixed brassica + cereal summer cover crop or iii) a cropping sequence with a temporary legume intercrop in the wheat phase of the rotation. Cover crop biomass production, soil water to a depth of 90 cm at cash crop sowing, crop yields and soil functional indices were quantified. ResultsCover crops produced 500–700 kg biomass ha−1 in the 2020 and 2021 seasons and 1000–2400 kg biomass ha−1 in 2022. The four-species mixed cover crop significantly lowered soil water (around 30 mm; P < 0.05) at the time of sowing the cash crop compared to the control and resulted in 15% reduction (P = 0.12) in canola seed yield in 2020, but no significant effect of cover crops of soil water and mineral N at sowing, or cash crop yields, were observed in subsequent seasons. In 2021 the temporary vetch intercrop produced > 1000 kg ha−1 biomass over 9 weeks, and led to a (non-significant) 10% wheat yield reduction. There was no significant effect of cover crop or temporary intercrop treatments on soil functions in the 2020 or 2021 seasons, but activities of several soil enzymes (leucine aminopeptidase, arylsulfatase and B-glucosidase; P < 0.05) and water-soluble carbon (P = 0.059) were significantly higher in the summer cover crop plots compared to control and intercrop plots in March 2022 following termination of the cover crops. These changes coincided with a significant increase in saturated hydraulic conductivity in the four-species cover crop plots in March 2022 compared to control plots. ImplicationsThe study did not provide any compelling evidence for benefits of summer cover crops over fallow in the short term (3–4 years). The relatively low cover crop biomass production over the 4-year study suggests summer cover crops are unlikely to substantially improve soil carbon levels in temperate, semi-arid cropping systems.

Comparative Studies of Lepidopteran Pest Incidence on JL 24 and DH 256 Varieties of Groundnut

This experiment compares the incidence of lepidopteran pests under protected and unprotected groundnut cultivation at AICRP on Groundnut, MARS, Dharwad, Karnataka in the kharif season of 2021–2022. In order to protect the protected plot from pests, protection measures were implemented at 50 DAS using flubendiamide 20 WG @ 0.5g/l for leaf-eating caterpillars. Based on the crop's phenology, observations were made. Spodoptera litura, Thysanoplusia orichalcea, Helicoverpa armigera, and Maruca vitrata, were deemed to be the main pests, with the remaining pests being of less significance based on their population density and type of damage. When comparing unprotected JL-24 and DH-256 crop plots to protected plots, the majority of major and minor pests were infested during the vegetative to maturity stage, with maximum infestation occurring during the pod formation and pod filling stages of the crop. In comparison to unprotected plots, protected plots had the highest pod and haulm yields.

Assessing relationships of cover crop biomass and nitrogen content to multispectral imagery

AbstractCover crops provide valuable roles in sustainable agriculture, provided they produce enough biomass. To accurately measure their services to field management, spatial estimates would be useful to producers. This study used multispectral drone imagery to produce maps of normalized difference vegetation index (NDVI), normalized difference red edge index (NDRE), and a digital surface model (DSM) of cover crop plots on sandy, Mid‐Atlantic soils. Cover crops included cereal rye (Secale cereale), mixtures of rye and crimson clover (Trifolium incarnatum), and mixtures of rye and hairy vetch (Vicia villosa). Their biomass was sampled in the spring of 2019, 2020, and 2021, dried, weighed, and analyzed for total nitrogen (N) content. Measurements of NDVI became saturated (i.e., reached a linear plateau) at 3.86 Mg biomass ha−1, NDRE at 5.72 Mg biomass ha−1, and the DSM at 5.11 Mg biomass ha−1. The measured N content became saturated at 80.9, 139.1, and 75 kg N ha−1 for NDVI, NDRE, and the DSM, respectively. Based on log transformations, NDVI was a stronger predictor of biomass and N, but not C:N. The NDRE was important for biomass, N, and C:N, while the DSM interactions with cover crop species helped predict both the N content and C:N of cover crop tissues. Accumulated growing degree days was important as an individual variable for biomass and N and as an interaction with cover crop species.

Winter game crop plots for gamebirds retain hedgerow breeding songbirds in an improved grassland landscape

The cause of recent population declines in some farmland/hedgerow breeding bird species in the UK is related to a lack of cover and food resources in winter. In improved grassland areas some of those declines have been particularly acute and some have been shown to be related to the availability of grass and weed seed in winter. The provision of seed‐bearing crops as part of AES options has been shown to benefit some of these birds. Game crop plots sown on shooting estates for holding and driving gamebirds in autumn and winter have been shown to hold relatively high densities of farmland and wood‐edge birds during the winter.We studied breeding songbirds in hedges in a primarily improved grassland area in the SW of England where there are some large shooting estates that sow relatively large game crop plots (1–5 ha) in the landscape. In this study we found that otherwise similar hedges in terms of size and density near to those winter game crop plots, had between 1.5 and 2 times as many breeding resident songbirds per unit length the following spring compared to hedges further away from game crop plots. This was despite game management in these plots being wound down during February and in many cases, the crops themselves being removed by mid‐March. Hedges within approximately 350 m from game crop plots had more breeding birds. We discuss possible mechanisms and suggest that some passerines preferentially establish breeding territories in hedges near to game crops in late winter. We suggest how to distribute game crop plots to maximise any benefit in an improved grassland landscape.

An Investigation into the Impacts of Preparatory Tillage and Nutrient Management on Barley Yield and Economic Viability in the Context of Water Stress Conditions

A number of field tests were carried out at the Chandra Shekhar Azad University of Agriculture and Technology's Soil Conservation and Water Management Farm in Kanpur, Uttar Pradesh, during the successive rabi seasons of 2020–21 and 2021–22. The gangatic alluvial soil in the study area had a pH of 7.6, which was indicative of its light texture and moderate soil fertility. The study included three different treatments that included preparatory tillage techniques: T1 treatment was one cross plowing with a cultivator; T2 treatment was one disc harrow plowing followed by another cross plowing with a cultivator; and T3 treatment was one disc harrow plowing plus one rotavator pass. The experiment also looked into three different nutrient management strategies: N1, which involved applying 100% of the Recommended Dose of Fertilizers (RDF)—60 kg of N, 30 kg of P2O5, and 30 kg of K2O—through chemical fertilizers; N2, which involved applying 75% of the RDF through chemical fertilizers along with 25% of Farm Yard Manure (FYM); and N3, which applied 50% of the RDF through chemical fertilizers along with 50% of FYM. In addition to applying 50% RDF through chemical fertilizers combined with 50% FYM, the results of the two-year experiment showed that planting barley crops in plots that received one disc harrow plowing and one rotavator pass yielded the maximum values across growth factors, yield attributes (such as grain yield q ha-1, straw yield q ha-1, biological yield q/ha, as well as harvest index), net return, gross return, and the barley benefit-to-cost ratio. This was noted in both years in a consistent manner. The next best results were seen with preparatory tillage, which involved using a cultivator to plough a single cross and applying chemical fertilizers to achieve 100% RDF (N1: 60 kg N ha-1 + 30 kg P2O5ha-1 + 30 kg K2Oha-1).

Artificial intelligence and Internet of Things‐enabled decision support system for the prediction of bacterial stalk root disease in maize crop

AbstractAlthough the Internet of Things (IoT) has been considered one of the most promising technologies to automate various daily life activities, that is, monitoring and prediction, it has become extremely useful for problem solving with the introduction and integration of artificial intelligence (AI)‐enabled smart learning methodologies. Therefore, due to their overwhelming characteristics, AI‐enabled IoTs have been used in different application environments, such as agriculture, where detection, prevention (if possible), and prediction of crop diseases, especially at the earliest possible stage, are desperately required. Bacterial stalk root is a common disease of tomatoes that severely affects its production and yield if necessary measures are not taken. In this article, AI and an IoT‐enabled decision support system (DSS) have been developed to predict the possible occurrence of bacterial stalk root diseases through a sophisticated technological infrastructure. For this purpose, Arduino agricultural boards, preferably with necessary embedded sensors, are deployed in the agricultural field of maize crops to capture valuable data at a certain time interval and send it to a centralized module where AI‐based DSS, which is trained on an equally similar data set, is implemented to thoroughly examine captured data values for the possible occurrence of the disease. Additionally, the proposed AI‐ and IoT‐enabled DSS has been tested on benchmark data sets, that is, freely available online, along with real‐time captured data sets. Both experimental and simulation results show that the proposed scheme has achieved the highest accuracy level in timely prediction of the underlined disease. Finally, maize crop plots with the proposed system have significantly increased the yield (production) ratio of crops.

Evaluating the Yields of the Rainfed Potato Crop under Climate Change Scenarios Using the AquaCrop Model in the Peruvian Altiplano

Ensuring global food security and adapting to the challenges posed by climate change, particularly in rainfed agriculture, are paramount concerns. This research investigates the impacts of climate change on the yield of the potato crop variety Imilla Negra (Solanum tuberosum spp.) under the extreme climatic conditions of the Peruvian Altiplano. From the experimentation in six crop plots under a rainfed agricultural system, periodic crop growth parameter measurements were obtained from 2017 to 2018. The results showed a good performance of the AquaCrop model in the calibration and validation, successfully simulating crop growth and yield parameters. Climate projections showed precipitation decreases and temperature and evapotranspiration increases for the representative concentration pathway (RCP), RCP 4.5, and RCP 8.5 scenarios in 2023–2050. A comparison of crop yields between the base period (2006–2021) and the period 2023–2037 showed no significant changes, whereas a more considerable decrease was observed for the period 2038–2050. It is concluded that climate change generates moderate impacts on potato crop yields under the rainfed agricultural system in the Peruvian Altiplano due to the average reduction in precipitation.

Can strip cropping reduce pest activity density and damage while increasing yield? A case study of organic cabbage and faba bean

This study assessed how strip cropping white cabbage (Brassica oleracea) and faba bean (Vicia faba) affects the activity density of pests – diamondback moth (Plutella xylostella) and flea beetles (Phyllotreta spp.) – and how this affects crop yields. The setup consisted of three 270m2 plots representing monocrops of faba bean and cabbage, and a plot of alternating strips of the two. The setup was established in 2018 and 2019. Activity density of P. xylostella was determined through yellow sticky trapping and Phyllotreta spp. activity density was determined by pitfall trapping. Crop yields were determined at harvest, and foliar damage to cabbage leaves was also assessed. The results showed that strip cropping reduced the activity density of P. xylostella, but no suppression effect was observed for Phyllotreta spp. Average foliar damage to cabbage was higher in the strip crop plot, but in 2018 the yield was also higher. Average faba bean yield was lower in the strip crop plot in both years. Our results indicate potential for cabbage-faba bean strip cropping to reduce the activity density of P. xylostella but not Phyllotreta spp. and to increase cabbage yield when overall pest pressure is moderate, but at the cost of faba bean yield. The case study shows that a Brassica vegetable – legume strip cropping system has potential for pest suppression in northern conditions, but agronomic compatibility of crop plants needs attention to ensure similar or higher productivity than a monocrop system.

Exploring the mechanisms of diverging mechanical and water stability in macro‐ and microaggregates

AbstractBackgroundSoil stability is often evaluated using either mechanical or hydraulic stress. The few studies that use both approaches suggest that these two types of stability behave differently.AimsOur aim was to explore the mechanisms of aggregate stability regarding mechanical and water stability at the macro‐ and microscale, among other things, the effect of differing pore structure and soil organic matter content.MethodsSamples were taken from two adjacent plots that were expected to differ in stability due to land use, that is, cropped versus bare fallow (BF). The stability of dry‐separated macroaggregates (8–16 mm) and microaggregates (53–250 µm) was determined via wet sieving and unconfined uniaxial compression tests. To explore the mechanisms of stability, 3D pore characteristics were analyzed with microtomography scans. Furthermore, the contents of carbon and exchangeable polyvalent cations as well as contact angles were determined.ResultsWater stability of macroaggregates was much higher in the cropped plot (geometric mean diameter 0.65–2.37 mm [cropped] vs. 0.31–0.56 mm [BF]), while mechanical stability was very similar (median work 17.3 [cropped] and 17.5 N mm [BF]). The two size fractions behaved similarly regarding both types of stability, with more pronounced differences in macroaggregates. Several soil characteristics, like carbon, exchangeable calcium, and higher connectivity of pores to the aggregate exterior, contributed to water stability. Regarding mechanical stability, the destabilizing effect of lower carbon content and exchangeable calcium in the BF plot was counterbalanced by a lower porosity.ConclusionsMechanical and water stability behaved differently in the two plots due to the different deformation mechanisms.

Приживаемость культур сосны кедровой сибирской (Pinus sibirica Du Tour.) в условиях Ханты-Мансийского автономного округа — Югры

The article discusses the reasons for the low survival capacity of Siberian stone pine (Pinus sibirica Du Tour.) crops in the conditions of the West Siberian mid-taiga plain forest region. The field stage of research was performed in the autumn 2020 and the summer 2022. The survival capacity of forest crops was determined on rectangular trial plots covering 1–2 % of the total area of the surveyed plots. The article provides data on the location and description of the studied areas of Siberian stone pine crops, as well as data on the number of surviving plants and the survival capacity of seedlings in these plots. In the course of the research, it was found that the survival capacity of Siberian stone pine crops in the four studied plots was 7,8 (60,3 %) in 2020, and this figure decreased to 3,6 (39,8 %) in 2022. Along with many other possible causes of excessive death of Siberian stone pine seedlings, the most likely reasons for the poor survival capacity are soaking seedlings and suppressing them with unwanted herbaceous and woody vegetation. In the three study areas, it is recommended to write off forest crops and replant seedlings. In one of the studied crop plots, it is necessary to perform silvicultural maintenance in order to remove unwanted hardwoods and supplement forest crops with enlarged seedlings or seedlings of Siberian stone pine. To increase the survival capacity of Siberian stone pine crops, it is recommended to abandon soil cultivation methods in which the upper fertile soil layer is mixed with the underlying levels, as well as to perform agrotechnical and silvicultural maintenance in a timely manner.

Effects of conventional vs. organic farming practices on raptor nestling health: Neither black nor white

Agricultural intensification is one of the main threats to biodiversity. Farmland bird specialists such as Montagu’s harrier, Circus pygargus, are particularly at risk and declining. Conventional farming (CF) production systems usually involve landscape homogenisation, mechanisation, and the use of synthetic pesticides that may have direct and indirect effects on individuals. By contrast, organic farming (OF) systems typically promote agro-ecosystem health, which benefits biodiversity and the reproductive success of birds. However, the potential effects of agricultural systems on life history traits of Montagu’s harrier chicks have not been investigated. Still, altered life history traits could impair chick survival and future reproductive success, which may in turn impact population dynamics. Here, we investigated the effects of OF (measured as a percentage around nests at different buffer sizes from 100 m to 2000 m) on a set of life history traits covering the behaviour, physiology (haematological, immune and nervous systems) and body condition of 380 chicks from 137 nests monitored between 2016 and 2021. At a local scale (<2000 m), only the H/L ratio (indicative of physiological stress) and carotenoid-based ornaments were clearly related to OF percentage. At 600 m around the nest, a higher OF percentage increased the H/L ratio, suggesting that chicks experienced greater stress due to either increased human disturbance or higher intra-/interspecific negative interactions around OF crop plots. Carotenoid-based ornaments were more strongly coloured with increasing OF around the nest at 1500 m. Considering the role of carotenoids in both detoxification processes and expression of secondary sexual traits, this result may indicate that CF would lead either to a difference in nestlings’ diet and/or to a trade-off between organism’s maintenance and sexual characters. These findings suggest that farming practices at a local scale surrounding nest locations may have subtle effects on chick development, but also on trade-offs between important physiological functions. This study highlights the importance of a multi-trait approach when assessing adverse and beneficial effects of both OF and CF on individuals.

Crop Mapping Based on Sentinel-2 Images Using Semantic Segmentation Model of Attention Mechanism.

Using remote sensing images to identify crop plots and estimate crop planting area is an important part of agricultural remote sensing monitoring. High-resolution remote sensing images can provide rich information regarding texture, tone, shape, and spectrum of ground objects. With the advancement of sensor and information technologies, it is now possible to categorize crops with pinpoint accuracy. This study defines crop mapping as a semantic segmentation problem; therefore, a deep learning method is proposed to identify the distribution of corn and soybean using the differences in the spatial and spectral features of crops. The study area is located in the southwest of the Great Lakes in the United States, where corn and soybean cultivation is concentrated. The proposed attention mechanism deep learning model, A2SegNet, was trained and evaluated using three years of Sentinel-2 data, collected between 2019 and 2021. The experimental results show that this method is able to fully extract the spatial and spectral characteristics of crops, and its classification effect is significantly better than that of the baseline method, and it has better classification performance than other deep learning models. We cross verified the trained model on the test sets of different years through transfer learning in both spatiotemporal and spatial dimensions. Proving the effectiveness of the attention mechanism in the process of knowledge transfer, A2SegNet showed better adaptability.

Assessment of intensive periurban agriculture soil quality applying biomarkers in earthworms

Periurban agriculture in Argentina is carried out by farmers without adequate control. The indiscriminate agrochemical application for productivity improvement negatively impacts the environment. The objective of this work was to test the quality of periurban agricultural soils by performing bioassays with Eisenia andrei as an indicator. Soils belonging to two orchards with intensive production (S: strawberry/broccoli crop plot and G: tomato/pepper crop greenhouse - Moreno District, Buenos Aires, Argentina) were sampled during 2015 and 2016. As subcellular biomarkers, cholinesterases (ChE), carboxylesterases (CaE), and glutathione-S-transferases (GST) activities were analysed in E. andrei (7-day exposure). While no effect on ChE activities was observed, CaE activities were significantly reduced 18% (S-2016 soil). GST activities were increased 35% and 30% by S-2016 and G-2016, respectively. CaE decrease together with GST increase could be indicative of a negative disturbance. Concerning whole organism biomarkers, reproduction (56-day exposure), avoidance (3-day exposure), and feeding activity (bait-lamina test, 3-day exposure) were analysed. A reduced cocoons’ viability (50%), hatchability (55%), accompanied by a low number of juveniles (50%) were observed in all cases. Additionally, the earthworms exhibited significant avoidance responses to S-2015, S-2016 and G-2016 whereas G-2015 soil induced migration. No significant effect on the feeding activity was registered in any case. Most of the E. andrei biomarkers tested could constitute an early warning of harmful effects produced by polluted periurban soils, even if the agrochemical treatment applied remains unknown. The results reveal the need to develop an action plan to avoid further deterioration of the productive soil.

Evaluation of winter cover crop methods for management of flatheaded appletree borer (Coleoptera: Buprestidae).

Winter cover crops grown at the base of red maples (Acer rubrum L.) can reduce flatheaded appletree borer (Chrysobothris femorata Olivier; Coleoptera: Buprestidae; FAB) damage by both physically blocking preferred oviposition sites and altering the environment around them. However, cover crop competition negatively affects tree growth. To investigate long-term cover crop effects, trees grown with cover crop for 2 yr were transitioned to a standard herbicide practice. After 4 yr, trees in the initial 2 yr cover crop plots were 1 yr behind in growth compared to trees grown in bare rows for all 4 yr. Most growth reduction occurred in the first year following transplant. Additional borer losses of 1-2% per year were observed in production years 3 and 4. A second experiment answered 2 questions: Can killing the cover crop once it reaches maximal height protect trees from borers while also reducing competition and thereby increase tree growth? and Do herbicide applications increase borer attacks? In this experiment, red maples were grown with (i) a standard herbicide program, (ii) a mulch mat, (iii) a cover crop that was killed early, or (iv) a cover crop allowed to senesce naturally. Evaluations after 2 yr indicated early kill of the cover crop was not enough to improve tree growth. Further, trees in the early kill cover crop treatment had the most FAB attacks. Cover crops allowed to senesce naturally reduced FAB attacks in both studies; however, more work is needed to minimize disparities in tree growth during the initial year post-transplant and determine the causal relationship between herbicide use and borer attacks.

Harmfulness of cryptid and cabbage pod mosquito of the Steppe zone of Ukraine

Goal. To specify the species composition of phytophages and to investigate their harmfulness in winter rapeseed crops.&#x0D; Methods. The research was conducted in the Steppe zone in 2022 (Odesa region, Odesa district, Khlybodarske settlement, «Odesa State Agricultural Research Station of the Institute of Water Problems and Land Reclamation of the National Academy of Sciences»). Clarification of the species composition and the dynamics of the number of phytophages was carried out according to generally accepted methods.&#x0D; Results. During the surveys, insects belonging to 6 orders (Coleoptera, Heteroptera, Hemiptera, Diptera, Hymenoptera and Lepidoptera) were found, of which 47,3% were direct pests of winter rape, 10.8% were pests of grain crops (there were fields nearby, and research plots of grain and ear crops), and 41.9% are entomophages. At the time of research, there were an average of 46 rapeseed plants per 1 m2, with 36.7 ± 2.19 pods per plant. During visual inspections before harvesting, characteristic damage by the cabbage stem borer (Ceutorhynchus quadridens Panz.) was noted on the rape stalks — 31.0% of plants/ m2, and the plants were broken near the root neck. During the growth of the stem, the larval stages of this pest were found, which penetrated into the middle, biting the petiole of the leaf, then moved to the root neck, where they fed on the tissues of the plant for a long time, causing its fragility. It was found that damage to pods per 1 m2 was 21.9%. Of them, the seed gnat (Ceutorhynchus assimilis Payak.) — 18.0%, the cabbage pod mosquito (Dasyneura brassicae Winn.) — 3.9%. Total crop losses from the above-mentioned pests on winter rapeseed crops amounted to — 52.9%.&#x0D; Conclusions. It was established that the share of pests in the entomocomplex of rape agrocenosis was — 47.3%. Damage to winter rapeseed crops by cabbage seed borer was — 18.0%, cabbage pod mosquito — 3.9%, and cabbage stem borer — 31.0%, which in total resulted in 52.9% yield loss.