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Temperate insect species often enter diapause in preparation for overwintering. One such species is the invasive vinegar fly, Drosophila suzukii (Matsumura), which has seasonal polymorphisms, considered winter and summer morphs. To date, the morphs have been differentiated by color and size with winter morphs typically being darker and larger compared to summer morphs. 'Dark' and 'large' are subjective, however, and standardizing an identification process can ensure that the morph of interest is being accurately characterized. The goal of our research was to investigate a quantitative method to distinguish between D. suzukii morphs based on body and wing size. We reared winter and summer morph D. suzukii in the laboratory using standard procedures, and measured wing length, wing width, and hind tibia length. Additionally, we collected field D. suzukii to document the seasonal phenology of the morphs in Minnesota based on our model's cutoff criteria. A classification and regression tree analysis were used to determine which metrics would be best for predicting field-caught D. suzukii morphs. Using laboratory-reared flies as our known morphs for the training data in the classification model we developed classification trees based on wing length and the ratio of wing length to hind tibia length. The frequency of winter and summer morphs present in the field varied based on which classification tree was used. Nevertheless, we suggest ratio of wing length to hind tibia length as the most robust criteria for differentiating D. suzukii morphs because the ratio accounts for the size variability between laboratory-reared and field-caught flies and the error rate of misclassification is reduced to 0.01 for males. The results from this work can aid in future D. suzukii research by allowing scientists to objectively differentiate the morphs, and thereby improve our understanding of the biology and phenology of seasonal morph dynamics.

Transgenic maize engineered to express insecticidal proteins from the bacterium Bacillus thuringiensis (Bt) has become widely adopted in U.S. agriculture. In 2009, Bt maize was planted on more than 22.2 million hectares, constituting 63% of the U.S. crop. Using statistical analysis of per capita growth rate estimates, we found that areawide suppression of the primary pest Ostrinia nubilalis (European corn borer) is associated with Bt maize use. Cumulative benefits over 14 years are an estimated $3.2 billion for maize growers in Illinois, Minnesota, and Wisconsin, with more than $2.4 billion of this total accruing to non-Bt maize growers. Comparable estimates for Iowa and Nebraska are $3.6 billion in total, with $1.9 billion for non-Bt maize growers. These results affirm theoretical predictions of pest population suppression and highlight economic incentives for growers to maintain non-Bt maize refugia for sustainable insect resistance management.

As part of an insect resistance management plan to preserve Bt transgenic technology, annual monitoring of target pests is mandated to detect susceptibility changes to Bt toxins. Currently Helicoverpa zea (Boddie) monitoring involves investigating unexpected injury in Bt crop fields and collecting larvae from non-Bt host plants for laboratory diet bioassays to determine mortality responses to diagnostic concentrations of Bt toxins. To date, this monitoring approach has not detected any significant change from the known range of baseline susceptibility to Bt toxins, yet practical field-evolved resistance in H. zea populations and numerous occurrences of unexpected injury occur in Bt crops. In this study, we implemented a network of 73 sentinel sweet corn trials, spanning 16 U.S. states and 4 Canadian provinces, for monitoring changes in H. zea susceptibility to Cry and Vip3A toxins by measuring differences in ear damage and larval infestations between isogenic pairs of non-Bt and Bt hybrids over three years. This approach can monitor susceptibility changes and regional differences in other ear-feeding lepidopteran pests. Temporal changes in the field efficacy of each toxin were evidenced by comparing our current results with earlier published studies, including baseline data for each Bt trait when first commercialized. Changes in amount of ear damage showed significant increases in H. zea resistance to Cry toxins and possibly lower susceptibility to Vip3a. Our findings demonstrate that the sentinel plot approach as an in-field screen can effectively monitor phenotypic resistance and document field-evolved resistance in target pest populations, improving resistance monitoring for Bt crops.

Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) is an invasive pest of soft-skinned fruit causing significant damage on a variety of fruit crops in North America, Europe, and Asia. In North America, fall-bearing fruit, such as primocane raspberries, ripen when D. suzukii populations peak and thus are vulnerable to high levels of infestation. In recent years, growers in northern climates have increased raspberry production under protected culture (high tunnels), resulting in season extension, increased yield, and improved fruit quality. High tunnels may be used as a pest management tool by physically excluding insect pests. This study investigated whether D. suzukii can be excluded from fall-bearing raspberries cultivated under tunnels covered with plastic or fine mesh netting, and whether this production technique can improve fruit marketability and serve as an alternative to insecticide application. We found that berries in plastic-covered tunnels had low season-long levels of infestation by D. suzukii (mean = 2 %), compared to netted tunnels (35 %), insecticide-treated open plots (60 %) and untreated open plots (81 %). Our microclimate data show that temperature and humidity levels inside the plastic-covered tunnels were often outside the previously published optimal temperature range for development, mating, and/or oviposition for D. suzukii , and may have therefore limited overall population growth. We conclude that exclusion and modification of microclimate may be effective and complementary pest management strategies for fall-fruiting raspberry and serve as an alternative to insecticide applications, particularly for small-acreage and organic production systems.

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) produces an electrophysiological signature called evoked resonant neural activity (ERNA); a high-frequency oscillation that has been linked to treatment efficacy. However, the single-neuron and synaptic bases of ERNA are unsubstantiated. This study proposes that ERNA is a subcortical neuronal circuit signature of DBS-mediated engagement of the basal ganglia indirect pathway network. In people with Parkinson’s disease, we: (i) showed that each peak of the ERNA waveform is associated with temporally-locked neuronal inhibition in the STN; (ii) characterized the temporal dynamics of ERNA; (iii) identified a putative mesocircuit architecture, embedded with empirically-derived synaptic dynamics, that is necessary for the emergence of ERNA in silico; (iv) localized ERNA to the dorsal STN in electrophysiological and normative anatomical space; (v) used patient-wise hotspot locations to assess spatial relevance of ERNA with respect to DBS outcome; and (vi) characterized the local fiber activation profile associated with the derived group-level ERNA hotspot. Subthalamic deep brain stimulation produces evoked resonant neural activity (ERNA) which has been linked to therapeutic benefit. Using a multimodal approach, the authors propose that ERNA reflects activation of the basal ganglia indirect pathway network.

Although it is widely accepted that the cortex participates in pain perception, there is no direct evidence for the existence of cortical neurons that respond to noxious or painful stimuli in humans. Anatomical and neurophysiological studies in animals as well as brain imaging and evoked potential studies in humans suggest that the anterior cingulate cortex (ACC) is an important area for processing sensory information related to pain 1 , 2 , 3 , 4 , 5 , 6 , 7 . We have now identified single neurons in ACC that respond selectively to painful thermal and mechanical stimuli, supporting a role for the ACC in pain perception.

Western bean cutworm, Striacosta albicosta (Smith) (Lepidoptera: Noctuidae), is a native, univoltine pest of corn and dry beans in North America. The current degree-day model for predicting a specified percentage of yearly moth flight involves heat unit accumulation above 10°C after 1 May. However, because the moth's observed range has expanded into the northern and eastern United States, there is concern that suitable temperatures before May could allow for significant S. albicosta development. Daily blacklight moth catch and temperature data from four Nebraska locations were used to construct degree-day models using simple or sine-wave methods, starting dates between 1 January and 1 May, and lower (-5 to 15°C) and upper (20 to 43.3°C) developmental thresholds. Predicted dates of flight from these models were compared with observed flight dates using independent datasets to assess model performance. Model performance was assessed with the concordance correlation coefficient to concurrently evaluate precision and accuracy. The best model for predicting timing of S. albicosta flight used simple degree-day calculations beginning on 1 March, a 3.3°C (38°F) lower threshold, and a 23.9°C (75°F) upper threshold. The revised cumulative flight model indicated field scouting to estimate moth egg density at the time of 25% flight should begin when 1,432 degree-days (2,577 degree-days °F) have accumulated. These results underscore the importance of assessing multiple parameters in phenological models and utilizing appropriate assessment methods, which in this case may allow for improved timing of field scouting for S. albicosta.

In sub-Saharan Africa (SSA) and several Asian countries, maize continues to be a major staple food for millions of people. It plays an important role in food and nutrition security and as a source of income. Pests and diseases, however, are the primary biotic constraints to maize productivity in these countries. The recent invasion of the fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), throughout Africa and Asia threatens the production and food security goals of subsistence smallholder farmers throughout most of sub-Saharan Africa followed by spread to India in 2018 and China. FAW was first detected in West Africa from São Tomé, Nigeria, Bénin and Togo in early 2016. As of May 2019, FAW has now been confirmed in all sub-Saharan countries, and later on its occurrence has been reported in various Asian countries. FAW is a highly polyphagous pest attacking over 350 plant species, including several economically important crops such as maize (Zea mays L.), rice (Oryza sativa L.), cotton (Gossypium spp. L.), sorghum (Sorghum bicolor (L.) Moench) and several legumes that are also preferred hosts. In Africa, without effective FAW management options, this pest will cause substantial maize yield losses ranging from 8.3 to 20.6 million tonnes annually, with losses of$2.5–6.2 million. However, now that FAW is established in > 42 countries, the total annual impact is estimated at $ 13 billion. Although over 150 species of FAW parasitoids have been recorded in the Americas, there is still the demand of information regarding the potential of biological control in Africa, and alternative complementary management tactics. Given the ongoing damage potential of FAW in Africa, and now Asia, the urgency to develop practical management solutions at the farm level cannot be overemphasized. This review summarizes much of the global, current research that should be useful in developing FAW management programs for smallholder farmers in SSA and Asia. In so doing, we present an Integrated pest management (IPM) framework that relies on several foundational and compatible tactics, including timely monitoring of FAW, host plant resistance, biological control, cultural control, and when necessary, chemical control. Consequently, this review identifies several research gaps, as well as logical research objectives that should prove useful going forward. Finally, we explore how sustainable IPM systems for FAW can contribute to both long-term food security and environmental stewardship goals for agricultural production in sub-Saharan Africa and Asia-Pacific region.

Japanese beetle, Popillia japonica Newman, is an invasive insect, native to Japan. The species was detected in the United States in New Jersey in 1916, and then first confirmed in Minnesota in 1968. Since their arrival, P. japonica has become a major pest in turfgrass and several crop agroecosystems. As P. japonica continues to spread throughout the U.S., it's important to discover more efficient ways to monitor adult populations. In 2018–2020, due to the high volume of P. japonica beetles collected in traps, a comparison of weight and volume calibration methods was conducted in Minnesota. Each method yielded a strong goodness of fit with counts of beetles captured. However, with a goal of cost-effective use of traps and in-field estimates, the volume-based approach was the preferred, most efficient method. In addition, a comparison of monitoring systems was conducted to observe differences in trap type, lure age, and check interval. Results from these studies indicate a standard green/yellow trap, and multi-component, semiochemical-based lure used for the duration of the P. japonica flight period, and a weekly check interval will minimize sampling time and resources, while providing accurate population estimates. In addition, results from these studies will benefit growers and researchers as they continue to explore integrated pest management (IPM) strategies for P. japonica. More importantly, by reducing the time required to quantify trap catches and rebait traps, these results may also facilitate area-wide tracking of P. japonica populations in newly invaded regions.

Drosophila suzukii Matsumura (Diptera: Drosophilidae), or spotted-wing drosophila, is an invasive pest first detected in the United States in 2008. Although D. suzukii can use many cultivated fruit as hosts, raspberries are considered ‘most at risk’ for infestation. Conventional broad-spectrum insecticides are proven effective D. suzukii controls and can be economically profitable when combined with integrated pest management (IPM) on large-scale commercial raspberry farms. It remains unclear, however, whether organic controls are cost-effective strategies, particularly for farms operating on a small-scale seasonal basis, as is common in the Upper Midwest. The purpose of this paper is to explore the efficacy of two organic D. suzukii controls—exclusion netting for high tunnels and organic insecticides for open plots using data available from different field trials—and to ascertain whether any economic benefits of the organic controls outweigh treatment costs for small-scale raspberry operations under different risk scenarios. The field trials suggest that the organic treatments are effective controls for D. suzukii infestation and economically profitable. The exclusion netting treatment produced positive net returns compared to the alternative of no treatment and economically outperformed the organic-certified insecticide treatment for several yield, price and infestation scenarios. As D. suzukii infestation rates increased, net returns improved for both organic treatments. The economic results were robust across a range of yields and prices, suggesting that in almost all scenarios small scale organic raspberry growers benefit economically from the application of exclusion netting on high tunnels and insecticides for open plots.