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Background: Patients with Parkinson's disease might develop treatment‐resistant axial dysfunction after bilateral subthalamic stimulation. Objectives: To study whether lateralized stimulation (unilateral 50% amplitude reduction) for ≥21 days results in ≥0.13 m/s faster gait velocity in the dopaminergic ON state in these patients, and its effects on motor and axial function, quantitative gait and speech measures, quality of life, and selected cognitive tasks. Methods: Randomized, double‐blinded, double‐crossover trial. Results: In 22 participants (51–79 years old, 15 women), there were no significant changes in gait velocity, quality of life, cognitive, and speech measures. Reducing left‐sided amplitude resulted in a 2.5‐point improvement in axial motor Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS‐UPDRS) (P = 0.005, uncorrected) and a 1.9‐point improvement in the Freezing of Gait Questionnaire (P = 0.024, uncorrected). Conclusions: Lateralized subthalamic stimulation does not result in meaningful improvement in gait velocity in patients with Parkinson's disease who develop treatment‐resistant axial dysfunction after bilateral subthalamic stimulation. Left subthalamic overstimulation may contribute to axial deterioration in these patients. © 2022 International Parkinson and Movement Disorder Society [ABSTRACT FROM AUTHOR]

Minnesota is the state with the strongest winter warming in the contiguous United States. We performed regional climate projections at 10 km horizontal resolution using the Weather Research Forecasting model forced with eight CMIP5 GCMs. The selected GCMs have previously been found to be in relatively good agreement with observations over Minnesota compared to other members of the CMIP5 model ensemble. Our projections suggest ongoing warming in all seasons, especially in winter, as well as shallower snow depth and fewer days with snow cover. We expect significant increases in spring and early summer heavy precipitation events. Our comparisons between different time slices and two different emission scenarios indicate a climate for the state of Minnesota near the end of the 21st century that is significantly different from what has been observed by the end of the 20th century. Winters and summers are expected to be up to 6 and 4°C warmer, respectively, over northern and central Minnesota, and spring precipitation may increase by more than 1 mm d−1 over northern Minnesota. Especially over the central part of the state, winter snow depth is projected to decrease by more than 12 cm, and the number of days per year with snow depth of more than 2.54 cm (one inch) is expected to decrease by up to 55. Plain Language Summary: Minnesota is the state with the strongest winter warming in the contiguous United States. We performed regional projections of the climate across Minnesota for the middle and end of the 21st century. We selected the results from eight recent global climate model projections to calculate climate data over an area of 10 km by 10 km with a regional climate model. Our results indicate that the future climate for the state of Minnesota is likely to be significantly different from what has been observed near the end of the 20th century. Over northern and central Minnesota, winters and summers are expected to be up to 6 and 4°C warmer, respectively, near the end of the 21st century. Spring precipitation may increase by more than 1 mm d−1 over northern Minnesota. Over the central part of the state, winter snow depth is suggested to decrease by more than 12 cm. The number of days per year with snow depth of more than 2.54 cm (one inch) is expected to decrease by up to 55. These results are expected to influence regional decision‐making related to agriculture, infrastructure, water resources, and other sectors. Key Points: Over northern and central Minnesota, winters and summers may be up to 6 and 4°C warmer, respectively, at the end of the 21st centurySpring precipitation may increase by more than 1 mm per day over northern MinnesotaSnow depth may decrease by more than 12 cm. Number of snow days per year may decrease by up to 55 [ABSTRACT FROM AUTHOR]

European corn borer (ECB), Ostrinia nubilalis (Hubner), larvae develop resistance to management protocols in laboratory and field environments. Laboratory bioassays, tissue elemental analyses, and field resistance evaluations were conducted on ear tissues of maize, Zea mays L, to (i) identify genotypes and tissues which affect ECB development, (ii) isolate tissue extracts detrimentally affecting larvae, (iii) determine if high performance liquid chromatography (HPLC) absorption peaks are associated with biological activity, (iv) determine if ferulic acid and p-coumaric acid affect ECB larvae, and (v) determine if laboratory and field resistance are related. Tissue and genotype did not affect larval survival. Silk tissue from W182E, `Apache', MN 3153, and MN 276 reduced 10-d larval weight, increased time to pupation, reduced pupal weight, and increased time to moth emergence compared with kernel tissue, which did not differ from the cellulose control. Methanol fractions of silks reduced 10-d larval weight, but not larval survival, compared with the cellulose control. No methanol fraction of silks, except from MG 15, reduced 10-d larval weight as much as nonextracted Apache silk, suggesting that some allelochemicals were not captured or were lost during extraction. HPLC analysis detected three to four large peaks only found in active methanol fractions. Ear tissue element levels, except for manganese (r = -0.70), were not associated with decreased 10-d larval weight. Larvae reared on diet containing ferulic acid (2.61 and 1.67 mg/g) or p-coumaric acid (, TRADITIONAL FIELD SCREENING of sweet corn germplasm effectively increased ear resistance to European corn borer (Davis et al., 1993; Warnock et al., 1998). Sweet corn germplasm with improved native resistance [...]

Deep brain stimulation is an established therapy for several neurological disorders; however, its effects on neuronal activity vary across brain regions and depend on stimulation settings. Understanding these variable responses can aid in the development of physiologically-informed stimulation paradigms in existing or prospective indications. Provide experimental and computational insights into the brain-region-specific and frequency-dependent effects of extracellular stimulation on neuronal activity. In patients with movement disorders, single-neuron recordings were acquired from the subthalamic nucleus, substantia nigra pars reticulata, ventral intermediate nucleus, or reticular thalamus during microstimulation across various frequencies (1–100 Hz) to assess single-pulse and frequency-response functions. Moreover, a biophysically-realistic computational framework was developed which generated postsynaptic responses under the assumption that electrical stimuli simultaneously activated all convergent presynaptic inputs to stimulation target neurons. The framework took into consideration the relative distributions of excitatory/inhibitory afferent inputs to model site-specific responses, which were in turn embedded within a model of short-term synaptic plasticity to account for stimulation frequency-dependence. We demonstrated microstimulation-evoked excitatory neuronal responses in thalamic structures (which have predominantly excitatory inputs) and inhibitory responses in basal ganglia structures (predominantly inhibitory inputs); however, higher stimulation frequencies led to a loss of site-specificity and convergence towards neuronal suppression. The model confirmed that site-specific responses could be simulated by accounting for local neuroanatomical/microcircuit properties, while suppression of neuronal activity during high-frequency stimulation was mediated by short-term synaptic depression. Brain-region-specific and frequency-dependant neuronal responses could be simulated by considering neuroanatomical (local microcircuitry) and neurophysiological (short-term plasticity) properties. • Extracellular stimulation is brain-region-specific and frequency-dependent. • Neuronal stimulus responses were excitatory in thalamus & inhibitory in basal ganglia. • High-frequency stimulation led to neuronal suppression/a loss of site-specificity. • Responses to single stimuli could be predicted based on anatomy/local microcircuitry. • Frequency-dependant neuronal suppression could be modelled by synaptic depression. [ABSTRACT FROM AUTHOR]

Stink bugs represent an increasing risk to soybean production in the Midwest region of the United States. The current sampling protocol for stink bugs in this region is tailored for population density estimation and thus is more relevant to research purposes. A practical decision-making framework with more efficient sampling effort for management of herbivorous stink bugs is needed. Therefore, a binomial sequential sampling plan was developed for herbivorous stink bugs in the Midwest region. A total of 146 soybean fields were sampled across 11 states using sweep nets in 2016, 2017, and 2018. The binomial sequential sampling plans were developed using combinations of five tally thresholds at two proportion infested action thresholds to identify those that provided the best sampling outcomes. Final assessment of the operating characteristic curves for each plan indicated that a tally threshold of 3 stink bugs per 25 sweeps, and proportion infested action thresholds of 0.75 and 0.95 corresponding to the action thresholds of 5 and 10 stink bugs per 25 sweeps, provided the optimal balance between highest probability of correct decisions (≥ 99%) and lowest probability of incorrect decisions (≤ 1%). In addition, the average sample size for both plans (18 and 12 sets of 25 sweeps, respectively) was lower than that for the other proposed plans. The binomial sequential sampling plan can reduce the number of sample units required to achieve a management decision, which is important because it can potentially reduce risk/cost of management for stink bugs in soybean in this region. [ABSTRACT FROM AUTHOR]

Electrical stimulation in the kilohertz-frequency range has gained interest in the field of neuroscience. The mechanisms underlying stimulation in this frequency range, however, are poorly characterized to date. To summarize the manifold biological effects elicited by kilohertz-frequency stimulation in the context of the currently existing literature and provide a mechanistic framework for the neural responses observed in this frequency range. A comprehensive search of the peer-reviewed literature was conducted across electronic databases. Relevant computational, clinical, and mechanistic studies were selected for review. The effects of kilohertz-frequency stimulation on neural tissue are diverse and yield effects that are distinct from conventional stimulation. Broadly, these can be divided into 1) subthreshold, 2) suprathreshold, 3) synaptic and 4) thermal effects. While facilitation is the dominating mechanism at the subthreshold level, desynchronization, spike-rate adaptation, conduction block, and non-monotonic activation can be observed during suprathreshold kilohertz-frequency stimulation. At the synaptic level, kilohertz-frequency stimulation has been associated with the transient depletion of the available neurotransmitter pool – also known as synaptic fatigue. Finally, thermal effects associated with extrinsic (environmental) and intrinsic (associated with kilohertz-frequency stimulation) temperature changes have been suggested to alter the neural response to stimulation paradigms. The diverse spectrum of neural responses to stimulation in the kilohertz-frequency range is distinct from that associated with conventional stimulation. This offers the potential for new therapeutic avenues across stimulation modalities. However, stimulation in the kilohertz-frequency range is associated with distinct challenges and caveats that need to be considered in experimental paradigms. • Despite growing interest, the mechanisms underlying kilohertz-frequency stimulation are poorly characterized to date. • We performed a comprehensive literature search to characterize the neural effects underlying kilohertz-frequency stimulation. • Kilohertz-frequency stimulation yields distinct sub- and suprathreshold effects that are unique to this frequency range. • Phenomena include: facilitation, desynchronization, non-monotonic activation, spike-rate adaptation, conduction block, and synaptic fatigue. • The spectrum of distinct neuronal responses may offer the potential for new therapeutic avenues. [ABSTRACT FROM AUTHOR]

Parkinson's disease is a neurodegenerative disease affecting the supply of dopamine to basal ganglia nuclei, leading to pathological beta band (13–35 Hz) oscillations in the subthalamic nucleus (STN). STN and beta activity are recognized in motoric functions but their role in cognitive functions remains elusive. We examined single unit and beta local field potential (LFP) activity in the STN during a visual choice preference task in PD patients (n = 12) undergoing deep brain stimulation surgery. Patients viewed 2 of 5 possible animal picture‐pairs and were instructed to choose their favorite ("fav") picture by clicking the left or right mouse key. A block of trials consisted of 50–75 picture‐pair presentations. Single unit histograms and LFP spectrograms were aligned to picture presentation and point of decision for pairs that included the fav and non‐fav pictures, respectively. A total of 58 neurons from 26 blocks of trials were analyzed. Thirty of 58 neurons showed a selective change in spiking activity 0.20–0.65 s to fav picture presentation, which preceded the shortest recorded reaction time (=0.7 s), and 17/58 neurons showed no significant response in our task. Beta LFP significantly desynchronized in response to fav but not non‐fav pictures in all trials, and in 14/26 blocks of trials, the desynchronization was followed by a "beta burst" and ramp‐up to baseline activity. Neurons with choice preference responses were found throughout the dorsoventral extent of the STN. STN single units and beta activity are modulated during visual choice preference, and this suggests a role for STN beta activity in cognitive processing. [ABSTRACT FROM AUTHOR]

Data were collected through interviews with campus-based faculty, telephone surveys of 84 Extension field faculty, and focus group discussions. Differences between campus and field faculty included supervision, appointment, evaluation, publication, promotion and tenure, scholarly pursuit, and funding. Ways to improve campus and field faculty interaction were identified. (SK)

Magnetic resonance imaging-guided focused ultrasound (MRgFUS) is a novel method for stereotactic brain lesioning and has primarily been applied for thalamotomies to treat essential tremor (ET). The electrophysiological properties of previously MRgFUS-sonicated thalamic neurons have not yet been described. We report on an ET patient who underwent an MRgFUS thalamotomy but experienced tremor recurrence. We expanded the MRgFUS-induced thalamic cavity using radiofrequency (RF), with good effect on the tremor but transient sensorimotor deficits and permanent ataxia. This is the first report of a patient undergoing RF thalamotomy after an unsuccessful MRgFUS thalamotomy. As we used microelectrode recording to guide the RF thalamotomy, we could also study for the first time the electrophysiological properties of previously sonicated thalamic neurons bordering the MRgFUS-induced cavity. These neurons displayed electrophysiological characteristics identical to those recorded from nonsonicated thalamic cells in ET patients. Hence, our findings support the widespread assumption that sonication below the necrotic threshold does not permanently alter neuronal function. [ABSTRACT FROM AUTHOR]

The authors report the case of an elderly male in his 60s who, after 5 months of efficacious treatment with chronic deep brain stimulation of the subthalamic nucleus (STN-DBS), developed a hardware-related erosion necessitating removal of the complete DBS system. One and a half years following the first implantation, a new STN-DBS system was implanted along an immediately adjacent trajectory, and reproduction of clinical efficacy was reported. Additionally, 2 microstimulation protocols were compared between the 2 surgeries, i.e., one to assess the stimulation frequency response of STN neurons and another to assess inhibitory synaptic plasticity in the substantia nigra pars reticulata (SNr). The spontaneous neuronal firing rates of STN neurons in each hemisphere were also compared between the 2 surgeries. The results suggest that the frequency-sensitivity of STN neurons may have been reduced (i.e., more resistant to neuronal suppression), while the spontaneous baseline firing rates of STN neurons and the plasticity measured in the SNr remained unchanged (2 factors that may be indicative of neurodegenerative processes). [ABSTRACT FROM AUTHOR]

Spotted-wing drosophila, Drosophila suzukii (Matsumura), an economically damaging invasive species of numerous fruit crops, was first detected in Minnesota in 2012. High fecundity, and short generation times facilitated a rapid rise in the global pest status of D. suzukii, particularly in North America and Europe. To date, the majority of crop injury research has focused on fruit crops such as blueberries, raspberries, and cherries. However, little is known regarding the impact of D. suzukii on the wine grape industry in the upper Midwest region of the United States. Field trials were conducted in Minnesota during the summers of 2017–2018 to examine season-long phenology of D. suzukii in wine grape vineyards and wineries, and to assess the efficacy of exclusion netting for control of D. suzukii. Four treatments were evaluated, 1) open plot check (control), 2) open plot treated with an insecticide, 3) exclusion netting, and 4) exclusion netting, with artificial infestations of D. suzukii adults. Exclusion netting was applied at véraison and removed at harvest. On each sample date, 20 berries (10 intact and 10 injured) were collected from each plot for dissection. The number of larvae and adults were recorded for each berry to determine infestation levels. As shown by mean larval infestations and injured berries across treatments, exclusion netting provided a significant reduction in the level of D. suzukii infested berries when compared with the untreated check. These results indicate that exclusion netting could provide an effective alternative management strategy for D. suzukii in wine grapes. [ABSTRACT FROM AUTHOR]

Tremor is a well-known side effect from many psychiatric medications, including lithium and dopamine antagonists. In patients whose psychiatric symptoms are stabilized and only respond to certain medications, deep brain stimulation may offer relief of the consequent motor complications. We report the case of an elderly male with disabling tremor related to lithium therapy for bipolar affective disorder, who was subsequently treated with deep brain stimulation. In this patient, we obtained recordings from the substantia nigra pars reticulata and performed a high-frequency stimulation protocol that robustly elicits long-term potentiation (LTP)-like changes in patients with Parkinson's disease. We hypothesized that in this patient, who did not have Parkinson's disease, the levels of inhibitory plasticity would be much greater. However, we found an unanticipated lack of plasticity in the patient with lithium-induced tremor, compared with two de novo control patients with Parkinson's disease. This patient was successfully treated with deep brain stimulation in the vicinity of the ventral oral posterior nucleus, an area of the thalamus that receives inputs from the basal ganglia. We postulate that the lithium-induced blockade of LTP may bring about motor complications such as tremor while simultaneously contributing to the therapeutic mechanism for treating the symptoms of psychiatric disorders such as bipolar affective disorder. [ABSTRACT FROM AUTHOR]

Population responses to environmental extremes often dictate the bounds to species' distributions. However, population dynamics at, or near, those range limits may also be affected by sublethal effects. We exposed late instars and pupae of an invasive leafroller, Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae), to cold temperatures and measured the effects of exposure on subsequent survivorship, development, and reproduction. Cold temperature was applied as acute exposure to –10 °C (a low, but not immediately lethal temperature for this species) or the onset of freezing (the peak of the supercooling point exotherm). Survival was defined as the ability to successfully eclose as an adult. We measured immature development times, pupal mass, and adult longevity as proxies of fitness in survivors. Additionally, surviving insects were mated with individuals that had not been exposed to cold to measure fertility. There was no difference between the proportion of larvae or pupae that survived acute exposure to –10 °C and those exposed to the control temperature. Approximately 17% of larvae and 8% of pupae survived brief periods with internal ice formation and continued development to become reproductively viable adults. Importantly, surviving the onset of freezing came with significant fitness costs but not to exposure to –10 °C; most insects that survived partial freezing had lower fertility and shorter adult lifespans than either the –10 °C or control group. These results are discussed within the context of forecasting invasive insect distributions. [ABSTRACT FROM AUTHOR]

Objective: Many lines of evidence suggest that response conflict recruits brain regions in the cortical-basal ganglia system. Within the basal ganglia, deep brain recordings from the subthalamic nucleus (STN) have shown that conflict triggers a transient increase in low-frequency oscillations (LFOs; 2-8Hz). Here, we deployed a new method of delivering short trains of event-related deep brain stimulation (DBS) to the STN to test the causal role of the STN and its associated circuits in conflict-related processing.Methods: In a double-blind design, we stimulated the STN in patients with Parkinson disease by locking brief trains of DBS to specific periods of the trial within a Stroop task.Results: Stimulation had a specific effect on conflict compared to nonconflict trials by relatively speeding responses on conflict trials (ie, reducing the Stroop effect, defined as the difference in reaction time between conflict and nonconflict trials) when it was delivered in the preresponse period in the preparation phase. Stimulation also increased errors when it was delivered early in the response window. This latter result corresponded to the timing of the conflict-induced increase in LFOs observed in the absence of stimulation but was not directly related to the reduction in the Stroop effect.Interpretation: These results support the theory that the time of LFO increase recorded from the STN corresponds to a conflict-processing function. They also provide one of the first demonstrations of event-related DBS of the STN in humans during a cognitive control paradigm. Ann Neurol 2018;84:515-526. [ABSTRACT FROM AUTHOR]

Ventral intermediate thalamic deep brain stimulation is a standard therapy for the treatment of medically refractory essential tremor and tremor-dominant Parkinson's disease. Despite the therapeutic benefits, the mechanisms of action are varied and complex, and the pathophysiology and genesis of tremor remain unsubstantiated. This intraoperative study investigated the effects of high frequency microstimulation on both neuronal firing and tremor suppression simultaneously. In each of nine essential tremor and two Parkinson's disease patients who underwent stereotactic neurosurgery, two closely spaced (600 µm) microelectrodes were advanced into the ventral intermediate nucleus. One microelectrode recorded action potential firing while the adjacent electrode delivered stimulation trains at 100 Hz and 200 Hz (2-5 s, 100 µA, 150 µs). A triaxial accelerometer was used to measure postural tremor of the contralateral hand. At 200 Hz, stimulation led to 68 ± 8% (P < 0.001) inhibition of neuronal firing and a 53 ± 5% (P < 0.001) reduction in tremor, while 100 Hz reduced firing by 26 ± 12% (not significant) with a 17 ± 6% (P < 0.05) tremor reduction. The degree of cell inhibition and tremor suppression were significantly correlated (P < 0.001). We also found that the most ventroposterior stimulation sites, closest to the border of the ventral caudal nucleus, had the best effect on tremor. Finally, prior to the inhibition of neuronal firing, microstimulation caused a transient driving of neuronal activity at stimulus onset (61% of sites), which gave rise to a tremor phase reset (73% of these sites). This was likely due to activation of the excitatory glutamatergic cortical and cerebellar afferents to the ventral intermediate nucleus. Temporal characteristics of the driving responses (duration, number of spikes, and onset latency) significantly differed between 100 Hz and 200 Hz stimulation trains. The subsequent inhibition of neuronal activity was likely due to synaptic fatigue. Thalamic neuronal inhibition seems necessary for tremor reduction and may function in effect as a thalamic filter to uncouple thalamo-cortical from cortico-spinal reflex loops. Additionally, our findings shed light on the gating properties of the ventral intermediate nucleus within the cerebello-thalamo-cortical tremor network, provide insight for the optimization of deep brain stimulation technologies, and may inform controlled clinical studies for assessing optimal target locations for the treatment of tremor. [ABSTRACT FROM AUTHOR]

Modern functional neurosurgery for movement disorders such as Parkinson's disease, tremor, and dystonia involves the placement of focal lesions or the application of deep brain stimulation (DBS) within circuits that modulate motor function. Precise targeting of these motor structures can be further refined by the use of electrophysiological approaches. In particular, microelectrode recordings enable the delineation of neuroanatomic structures. In the course of these operations, there is an opportunity not only to map basal ganglia structures but also to gain insights into how disturbances in neural activity produce movement disorders. In this review, we aim to highlight what the field has uncovered thus far about movement disorders through DBS. The work to date lays the foundation for future studies that will shed further light on dysfunctional circuits mediating diseases of the nervous system and how we might modulate these circuits therapeutically. [ABSTRACT FROM AUTHOR]

A farmer’s decision on whether to control a pest is usually based on the perceived threat of the pest locally and the guidance of commercial advisors. Therefore, farmers in a region are often influenced by similar circumstances, and this can create a coordinated response for pest control that is effective at a landscape scale. This coordinated response is not intentional, but is an emergent property of the system. We propose a framework for understanding the intrinsic feedback mechanisms between the actions of humans and the dynamics of pest populations and demonstrate this framework using the European corn borer, a serious pest in maize crops. We link a model of the European corn borer and a parasite in a landscape with a model that simulates the decisions of individual farmers on what type of maize to grow. Farmers chose whether to grow Bt-maize, which is toxic to the corn borer, or conventional maize for which the seed is cheaper. The problem is akin to the snow-drift problem in game theory; that is to say, if enough farmers choose to grow Bt maize then because the pest is suppressed an individual may benefit from growing conventional maize. We show that the communication network between farmers’ and their perceptions of profit and loss affects landscape scale patterns in pest dynamics. We found that although adoption of Bt maize often brings increased financial returns, these rewards oscillate in response to the prevalence of pests. [ABSTRACT FROM AUTHOR]

Cost-effective and reliable sampling procedures are crucial for integrated pest management. Sweep net sampling is commonly used for stink bugs (Hemiptera: Pentatomidae) in soybean, with sample size being the number of sets of sweeps, and sample unit size the number of sweeps in each set. Sample unit size has received little attention, but can affect sampling parameters. Here, two sample unit sizes (10 vs. 25 sweeps) were compared for the sampling of stink bug taxa. On average, sampling for stink bugs took 3.6 more minutes with the 25-sweep than with the 10-sweep sample unit size. Generally, estimates of the mean number of stink bugs per sweep were similar between the two sample unit sizes for Euschistus spp. and Chinavia hilaris combined ("combined herbivores") and Euschistus spp. The 25-sweep sample unit size had a higher probability of detecting combined herbivores, Euschistus spp. and Podisus spp., lower standard errors and relative variance for combined herbivores and Euschistus spp., lower standard errors for C. hilaris , and higher relative net precision [which accounts for sampling cost (i.e., time)] for combined herbivores and Euschistus spp. Taken together, the better probability of detection, precision and efficiency of the 25-sweep sample unit size support the continued use of sampling plans developed for that sample unit size. The optimization of sample unit sizes is an important factor that should be accounted for in the development of sampling plans. • Two sample unit sizes (10 vs. 25 sweeps) were compared for sampling of stink bug taxa. • Probability of detection, precision and efficiency were higher with 25 sweeps. • Sample unit sizes should be evaluated when implementing sampling plans. [ABSTRACT FROM AUTHOR]

Transgenic maize MON88017, expressing the Cry3Bb1 toxin from Bacillus thuringiensis (Bt maize), confers resistance to corn rootworms (Diabrotica spp.) and provides tolerance to the herbicide glyphosate. However, prior to commercialization, substantial assessment of potential effects on non-target organisms within agroecosystems is required. The MON88017 event was therefore evaluated under field conditions in Southern Bohemia in 2009–2011, to detect possible impacts on the above-ground arthropod species. The study compared MON88017, its near-isogenic non-Bt hybrid DK315 (treated or not treated with the soil insecticide Dursban 10G) and two non-Bt reference hybrids (KIPOUS and PR38N86). Each hybrid was grown on five 0.5 ha plots distributed in a 14-ha field with a Latin square design. Semiquantitative ELISA was used to verify Cry3Bb1 toxin levels in the Bt maize. The species spectrum of non-target invertebrates changed during seasons and was affected by weather conditions. The thrips Frankliniella occidentalis was the most abundant species in all three successive years. The next most common species were aphids Rhopalosiphum padi and Metopolophium dirhodum. Frequently observed predators included Orius spp. and several species within the Coccinellidae. Throughout the three-year study, analysis of variance indicated some significant differences (P<0.05). Multivariate analysis showed that the abundance and diversity of plant dwelling insects was similar in maize with the same genetic background, for both Bt (MON88017) and non-Bt (DK315) untreated or insecticide treated. KIPOUS and PR38N86 showed some differences in species abundance relative to the Bt maize and its near-isogenic hybrid. However, the effect of management regime on arthropod community was insignificant and accounted only for a negligible portion of the variability. [ABSTRACT FROM AUTHOR]