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Ovipositional behaviour and larval performance of <i>Trichoferus campestris</i> (Faldermann) (Coleoptera: Cerambycidae) on cut branches of four North American tree species

Abstract Velvet longhorned beetle Trichoferus campestris (Faldermann) (Coleoptera: Cerambycidae) is native to Asia. It is reported to be polyphagous in its native range, but hosts have not been screened in its introduced range in the United States. We conducted choice and no‐choice host experiments. For choice assays, gravid T. campestris oviposited freely on cut branches of four tree species: Juglans nigra, Malus domestica, Acer saccharum, and Pinus strobus. We investigated oviposition between apple branches with and without cankers. Half of the choice trials underwent winter temperatures. For no‐choice assays, eggs were placed on cut branches of these same four species. Half of these branches were later dissected to measure larval development. The rest were exposed to winter temperatures and T. campestris emergence was quantified. Overall, Trichoferus campestris oviposition and development occur more readily on J. nigra and M. domestica than on A. saccharum or P. strobus. The insect oviposited more on cankered than uncankered apple wood. Cold exposure during an overwintering period benefitted insect development in adults. The insect's high degree of polyphagy and ability to reproduce in dry wood has likely facilitated its establishment in multiple locales around the world.

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Aspect ratio and baffles impact hydraulic performance of full-size denitrifying bioreactors

Denitrifying woodchip bioreactors treating subsurface drainage in the US have high aspect ratios (i.e., length: width ratios; approximately 4:1) to encourage plug flow dynamics. Improved understanding of bioreactor hydraulics across aspect ratios would help assess possible increased flexibility for this practice to capture greater hydraulic loading or provide greater nitrate mass removal. The objective of this study was to assess the hydraulic impacts of aspect ratio and baffles using conservative tracer testing at full-scale denitrifying woodchip bioreactors. Fourteen tracer tests were performed at six bioreactors, spanning three design styles: (1) “conventional” bioreactors with high aspect ratios of ≥2.6:1; (2) a “wide” bioreactor with a low aspect ratio of 0.3:1; and (3) a relatively wide “advanced” bioreactor with baffles placed to route flow sinuously perpendicular (sideways) to the hydraulic gradient. The wide bioreactor had the most dispersion, the most short circuiting, and was the most well mixed based on the tanks-in-series model. The advanced design with baffles had higher volumetric efficiencies than the conventional and wide designs (2.9, 2.2, and 2.1, respectively) and trended toward the highest nitrate removals. The concept of baffles at relatively wide bioreactors merits additional field-scale assessment to increase hydraulic loading while maintaining hydraulic efficiency. The Morill Dispersion and Short Circuiting Indices were strongly and significantly correlated (Pearson's r: −0.88) across the fourteen tests as were the volumetric and hydraulic efficiency metrics (r: 0.87). While aspect ratio and baffles have been well studied in wetlands and other reactor types, this work is the first to establish these concepts using tracer testing at three woodchip bioreactor design styles.

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Spray water quality and herbicide performance: a review

AbstractWater is the primary carrier for herbicide applications. Spray water qualities such as pH, hardness, temperature, or turbidity can influence herbicide performance and may need to be amended for optimum weed control. Water quality factors can affect herbicide activity by reducing solubility, enhancing degradation in the spray tank, or forming herbicide-salt complexes with mineral cations, thereby reducing the absorption, translocation, and subsequent weed control. The available literature suggests that the effect of water quality varies with herbicide chemistry and weed species. The efficacy of weak-acid herbicides such as glyphosate, glufosinate, clethodim, sethoxydim, bentazon, and 2,4-D is improved with acidic water pH; however, the efficacy of sulfonylurea herbicides is negatively impacted. Hard-water antagonism is more prevalent with weak-acid herbicides, and trivalent cations are the most problematic. Spray solution temperature between 18 C and 44 C is optimum for some weak-acid herbicides; however, their efficacy can be reduced at relatively low (5 C) or high (56 C) water temperature. The effect of water turbidity is severe on cationic herbicides such as paraquat and diquat, and herbicides with low soil mobility such as glyphosate. Although adjuvants are recommended to overcome the negative effect of spray water hardness or pH, the response has been inconsistent with the herbicide chemistry and weed species. Moreover, information on the effect of spray water quality on various herbicide chemistries, weed species, and adjuvants is limited; therefore, it is difficult to develop guidelines for improving weed control efficacy. Further research is needed to determine the effect of spray water factors and develop specific recommendations for improving herbicide efficacy on problematic weed species.

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ICP-MS Based Metallomics and GC-MS Based Metabolomics Reveals the Physiological and Metabolic Responses of Dendrobium huoshanense Plants Exposed to Fe 3 O 4 Nanoparticles

To improve the growth, yield and quality of Dendrobium huoshanense, Fe O NPs has been used as nano-fertilizer. Safety of Fe O NPs in medicinal production on D. huoshanense must be critically evaluated. In this study, two-year-old D. huoshanense was cultured in a solution containing Fe O NPs (100 or 200 mg/L) for 21 days. The results were investigated by a combination of phenotypic and non-target metabolomics based on gas chromatography-mass spectrometry (GC-MS). Fe O NPs induced not only earlier flowering and increased sugar content, photosynthesis, but also stress to plants, increased MDA content and related antioxidant enzymes activities. Fe O NPs caused a significant Fe and some other nutrient elements (Mn, Co, B, Mo) accumulation in stems based in Inductively Coupled Plasma Mass Spectrometry analysis. Metabolomics revealed that the metabolites were reprogrammed in D. huoshanense by Fe O NPs exposure. Fe O NPs can inhibit antioxidant defense-related pathways, suggesting that Fe O NPs had the antioxidant ability with plants accumulating relative metabolites to cope with stresses. As the first study associating Fe O NPs with the quality of D. huoshanense, it provided vital insights into the molecular mechanisms of how D. huoshanense responds to Fe O NPs, ensuring the reasonable use of Fe O NPs as nano-fertilizer.

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Biological control of Canada thistle (Cirsium arvense) revisited: host range of Hadroplontus litura on Cirsium species native to the Upper Midwest, USA

ABSTRACT In 1998, Hadroplontus (formerly Ceutorhynchus) litura, a stem-mining weevil, was introduced into a limited area in Minnesota for the biological control of Canada thistle, Cirsium arvense. Although showing a preference for C. arvense, initial host range testing in the 1960s indicated H. litura attacked other native Cirsium species. Before promoting or augmenting biocontrol with H. litura in Minnesota, we wanted to further define the host range of H. litura on native Cirsium species. Our objective was to determine whether H. litura could feed, oviposit and complete development on Cirsium spp. native to the Upper Midwest of the USA. In no-choice tests, female H. litura accepted all native Cirsium species for oviposition. In addition, H. litura was able to complete development to the adult stage on swamp thistle, Cirsium muticum, field thistle, Cirsium discolour, and tall thistle, Cirsium altissimum, and we confirmed the published host range test results of completed development on Flodman’s thistle, Cirsium flodmanii. These Cirsium species are within the fundamental host range of H. litura. No adults were found in development tests with Hill’s thistle, Cirsium pumilum var. hillii, a threatened or species of concern in the Upper Midwest, or Pitcher’s thistle, Cirsium pitcheri, a federally listed threatened species. Larval tunnelling was documented in C. pitcheri. We recommend that field tests be conducted, where search and host acceptance behaviour can occur under field conditions to further define the ecological host range of H. litura.

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Effect of Test Portion Mass on Vitamin A Testing in Animal Feed Materials.

BackgroundVitamin A test results have historically been notorious for poor repeatability and reproducibility. This problem has been discussed at length in Association of American Feed Control Officials Laboratory Methods and Services Committee meetings.ObjectiveThe objective of this work was to assess the effect of test portion mass on the repeatability of vitamin A test results.MethodsThe study was conducted in two parts. In Part I, fundamental sampling error (FSE) was determined experimentally through replicated (n = 16) vitamin A testing of three animal feed materials. The testing followed rigorous test portion selection for 10 g and 100 g test portions. In Part II, FSE calculations were made (1) using theoretical equations based on vitamin A as a liberated analyte and (2) on representing the particles in feed materials. Particle size characterization of vitamin A ingredients was estimated by microscopy and further evaluated by particle size analysis.ResultsRSDs, % for vitamin A determinations ranged from 10.5–24.7, and 2.26–10.7 for 10 g and 100 g test portions, respectively. FSE calculated for Ingredient A ranged from 18.3–101% and 5.79–32.0% for 10 g and 100 g test portions, respectively, and for Ingredient B, ranged from 10.2–56.2% and 3.21–17.8% for 10 g and 100 g test portions, respectively.ConclusionTest portion mass has a substantial impact on FSE and is an important factor in controlling the random error in vitamin A testing. FSE equations are useful to approximate minimum test portion mass.HighlightsVitamin A method development should use theoretical predictions and experimental verification to guide test portion mass. Strategies to deal with the larger test portion masses will be key to validating new methods.

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Multilaboratory Collaborative Study of a Nontarget Data Acquisition for Target Analysis (nDATA) Workflow Using Liquid Chromatography-High-Resolution Accurate Mass Spectrometry for Pesticide Screening in Fruits and Vegetables.

Nontarget data acquisition for target analysis (nDATA) workflows using liquid chromatography-high-resolution accurate mass (LC-HRAM) spectrometry, spectral screening software, and a compound database have generated interest because of their potential for screening of pesticides in foods. However, these procedures and particularly the instrument processing software need to be thoroughly evaluated before implementation in routine analysis. In this work, 25 laboratories participated in a collaborative study to evaluate an nDATA workflow on high moisture produce (apple, banana, broccoli, carrot, grape, lettuce, orange, potato, strawberry, and tomato). Samples were extracted in each laboratory by quick, easy, cheap, effective, rugged, and safe (QuEChERS), and data were acquired by ultrahigh-performance liquid chromatography (UHPLC) coupled to a high-resolution quadrupole Orbitrap (QOrbitrap) or quadrupole time-of-flight (QTOF) mass spectrometer operating in full-scan mass spectrometry (MS) data-independent tandem mass spectrometry (LC-FS MS/DIA MS/MS) acquisition mode. The nDATA workflow was evaluated using a restricted compound database with 51 pesticides and vendor processing software. Pesticide identifications were determined by retention time (tR, ±0.5 min relative to the reference retention times used in the compound database) and mass errors (δM) of the precursor (RTP, δM ≤ ±5 ppm) and product ions (RTPI, δM ≤ ±10 ppm). The elution profiles of all 51 pesticides were within ±0.5 min among 24 of the participating laboratories. Successful screening was determined by false positive and false negative rates of <5% in unfortified (pesticide-free) and fortified (10 and 100 μg/kg) produce matrices. Pesticide responses were dependent on the pesticide, matrix, and instrument. The false negative rates were 0.7 and 0.1% at 10 and 100 μg/kg, respectively, and the false positive rate was 1.1% from results of the participating LC-HRAM platforms. Further evaluation was achieved by providing produce samples spiked with pesticides at concentrations blinded to the laboratories. Twenty-two of the 25 laboratories were successful in identifying all fortified pesticides (0-7 pesticides ranging from 5 to 50 μg/kg) for each produce sample (99.7% detection rate). These studies provide convincing evidence that the nDATA comprehensive approach broadens the screening capabilities of pesticide analyses and provide a platform with the potential to be easily extended to a larger number of other chemical residues and contaminants in foods.

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