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Antarctic terrestrial biodiversity faces multiple threats, from invasive species to climate change. Yet no large-scale assessments of threat management strategies exist. Applying a structured participatory approach, we demonstrate that existing conservation efforts are insufficient in a changing world, estimating that 65% (at best 37%, at worst 97%) of native terrestrial taxa and land-associated seabirds are likely to decline by 2100 under current trajectories. Emperor penguins are identified as the most vulnerable taxon, followed by other seabirds and dry soil nematodes. We find that implementing 10 key threat management strategies in parallel, at an estimated present-day equivalent annual cost of US$23 million, could benefit up to 84% of Antarctic taxa. Climate change is identified as the most pervasive threat to Antarctic biodiversity and influencing global policy to effectively limit climate change is the most beneficial conservation strategy. However, minimising impacts of human activities and improved planning and management of new infrastructure projects are cost-effective and will help to minimise regional threats. Simultaneous global and regional efforts are critical to secure Antarctic biodiversity for future generations., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Lee et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Soybean ( Glycine max ) farmers in the Upper Midwest region of the United States often experience severe yield losses due to Sclerotinia stem rot (SSR). Previous studies have revealed benefits of individual management practices for SSR. This study examined the integration of multiple control practices on the development of SSR, yield, and the economic implications of these practices. Combinations of row spacings, seeding rates, and fungicide applications were examined in multisite field trials across the Upper Midwest from 2017 to 2019. These trials revealed that wide row spacing and low seeding rates individually reduced SSR levels but also reduced yields. Yields were similar across the three highest seeding rates examined. However, site-years where SSR developed showed the highest partial profits at the intermediate seeding rates. This finding indicates that partial profits in diseased fields were reduced by high seeding rates, but this trend was not observed when SSR did not develop. Fungicides strongly reduced the development of SSR while also increasing yields. However, there was a reduction in partial profits due to their use at a low soybean sale price, but at higher sale prices fungicide use was similar to not treating. Additionally, the production of new inoculum was predicted from disease incidence, serving as an indicator of increased risk for SSR development in future years. Overall, this study suggests using wide rows and low seeding rates in fields with a history of SSR while reserving narrow rows and higher seeding rates for fields without a history of SSR.

Corn silage, made from Zea mays , is a high-energy feed that is important for feeding dairy cows. Plant diseases, such as those caused by Fusarium graminearum , can decrease silage corn yields and quality. F. graminearum (teleomorph Gibberella zeae ) is an ascomycete fungus that causes Gibberella ear and stalk rot in corn. F. graminearum produces deoxynivalenol (DON), a secondary metabolite toxic to humans and animals. An understanding of the distribution of DON and F. graminearum throughout the corn plant is important for determining the quality of corn silage. A partitioned sample experiment that included two brown midrib silage hybrids and three fungicide treatments was conducted in research plots located in Arlington, WI, U.S.A., in 2018 and 2019. At harvest, stalk and ear parts were physically separated, dried, and ground for analysis. DON concentration (in parts per million) was determined using an enzyme-linked immunosorbent assay, and F. graminearum DNA concentration (in picograms per nanogram) was determined using quantitative PCR. DON and F. graminearum DNA were detected in all samples, demonstrating accumulation of the fungus in stalks and ears of the plant. In 2018, DON contamination was as high as 30 ppm and varied drastically between stalks and ears. In 2019, DON concentrations were much lower (<5 ppm), but were consistently higher in stalk samples than ear samples. Across all samples, DON concentrations and F. graminearum accumulation were highly correlated within the separated stalk ( r = 0.78) and ear portions ( r = 0.87) but were not correlated between ears and stalks. Depending on the weather and planting conditions in a given year, stalk infections or ear infections may occur by F. graminearum , leading to subsequent DON increases in those respective parts that are independent of each other.

Hemp fiber was used untreated and treated with sodium hydroxide or (3-aminopropyl)triethoxysilane (APTES) as an additive in polylactic acid (PLA) for fused filament fabrication (FFF) of tensile test specimens. Composites granules were produced by solvent processing with 10 wt. % of hemp fiber to use as feedstock for the extrusion of filaments compatible with commercial FFF printers. The dataset shows the thermal properties of the various composites, which were used to determine the appropriate temperatures required for extrusion of filaments and FFF printer settings. Microcomputed tomography imaging was performed and tensile mechanical properties of FFF-printed tensile test specimens were determined as a function of hemp fiber surface treatment. The data provides an assessment of the use of minimally processed hemp fiber as a filler or mechanical enhancer of thermoplastic materials for additive manufacturing., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships which have or could be perceived to have influenced the work reported in this article., (© 2021 The Authors.)

Fusarium graminearum commonly causes Fusarium head blight on wheat, barley, rice, and oats. F. graminearum produces nivalenol (NIV) and deoxynivalenol (DON) and forms derivatives of DON based on its acetylation sites. The fungus is profiled into chemotypes based on DON derivative chemotypes (3 acetyldeoxynivalenol [3ADON] chemotype; 15 acetyldeoxynivalenol [15ADON] chemotype), and/or the NIV chemotype. This study assessed the Fusarium population found on wheat and the chemotype profile of the isolates collected from 2016 and 2017 in Wisconsin. F. graminearum was isolated from all locations sampled in both 2016 and 2017. Fusarium culmorum was isolated only from Door County in 2016. Over both growing seasons, 91% of isolates were identified as the 15ADON chemotype, while 9% of isolates were identified as the 3ADON chemotype. Aggressiveness was quantified by area under the disease progress curve (AUDPC). The isolates with the highest AUDPC values were from the highest wheat-producing cropping districts in the state. Deoxynivalenol production in grain and sporulation and growth rate in vitro were compared with aggressiveness in the greenhouse. Our results showed that 3ADON isolates in Wisconsin were among the highest in sporulation capacity, growth rate, and DON production in grain. However, there were no significant differences in aggressiveness between the 3ADON and 15ADON isolates. The results of this research detail the baseline frequency and distribution of 3ADON and 15ADON chemotypes observed in Wisconsin. Chemotype distributions within populations of F. graminearum in Wisconsin should continue to be monitored in the future.

The asymptomatic host range of Fusarium virguliforme includes corn, a common crop rotated with soybean that we hypothesize may alter F. virguliforme population dynamics and disease management. A field-based approach explored the temporal dynamics of F. virguliforme colonization of corn and soybean roots under different tillage and residue managements. Experiments were conducted in Iowa, Indiana, Michigan, and Wisconsin, United States and Ontario, Canada from 2016 to 2018. Corn and soybean roots were sampled at consecutive timepoints between 1 and 16 weeks after planting. DNA was extracted from all roots and analyzed by real-time quantitative PCR for F. virguliforme quantification. Trials were rotated between corn and soybean, containing a two-by-two factorial of tillage (no-tilled or tilled) and corn residue (with or without) in several experimental designs. In 2016, low amounts (approximately 100 fg per 10 mg of root tissue) of F. virguliforme were detected in the inoculated Iowa, Indiana, and Michigan locations and noninoculated Wisconsin corn fields. However, in 2017, greater levels of F. virguliforme DNA were detected in Iowa, Indiana, and Michigan across sampling timepoints. Tillage practices showed inconsistent effects on F. virguliforme root colonization and sudden death syndrome (SDS) foliar symptoms among trials and locations. However, residue management did not alter root colonization of corn or soybean by F. virguliforme . Plots with corn residue had greater SDS foliar disease index in Iowa in 2016. However, this trend was not observed across the site-years, indicating that corn residue may occasionally increase SDS foliar symptoms depending on the disease level and soil and weather factors.

Soybean production in the upper midwestern United States is affected by Sclerotinia stem rot (SSR) caused by the fungal pathogen Sclerotinia sclerotiorum . Genetic resistance is an important management strategy for this disease; however, assessing genetic resistance to S. sclerotiorum is challenging because a standardized method of examining resistance across genotypes is lacking. Using a panel of nine diverse S. sclerotiorum isolates, four soybean lines were assessed for reproducible responses to S. sclerotiorum infection. Significant differences in SSR severity were found across isolates ( P < 0.01) and soybean lines ( P < 0.01), including one susceptible, two moderately resistant, and one highly resistant line. These four validated lines were used to screen 11 other soybean genotypes to evaluate their resistance levels, and significant differences were found across genotypes ( P < 0.01). Among these 11 genotypes, five commercial and public cultivars displayed high resistance and were assessed during field studies across the upper midwestern United States growing region to determine their response to SSR and yield. These five cultivars resulted in low disease levels ( P < 0.01) in the field that were consistent with greenhouse experiment results. The yields were significantly different in fields with disease present ( P < 0.01) and disease absent ( P < 0.01), and the order of cultivar performance was consistent between environments where disease was present or absent, suggesting that resistance prevented yield loss to disease. This study suggests that the use of a soybean check panel can accurately assess SSR resistance in soybean germplasm and aid in breeding and commercial soybean development.

A lack of complete resistance in the current germplasm complicates the management of Sclerotinia stem rot (SSR) caused by Sclerotinia sclerotiorum in soybean. In this study, we used bean pod mottle virus (BPMV) as a vehicle to down-regulate expression of a key enzyme in the production of an important virulence factor in S. sclerotiorum , oxalic acid (OA). Specifically, we targeted a gene encoding oxaloacetate acetylhydrolase ( Ssoah1 ), because Ssoah1 deletion mutants are OA deficient and non-pathogenic on soybean. We first established that S. sclerotiorum can uptake environmental RNAs by monitoring the translocation of Cy3-labeled double-stranded and small interfering RNA (ds/siRNAs) into fungal hyphae using fluorescent confocal microscopy. This translocation led to a significant decrease in Ssoah1 transcript levels in vitro . Inoculation of soybean plants with BPMV vectors targeting Ssoah1 (pBPMV-OA) also led to decreased expression of Ssoah1 . Importantly, pBPMV-OA inoculated plants showed enhanced resistance to S. sclerotiorum compared to empty-vector control plants. Our combined results provide evidence supporting the use of HIGS and exogenous applications of ds/siRNAs targeting virulence factors such as OA as viable strategies for the control of SSR in soybean and as discovery tools that can be used to identify previously unknown virulence factors., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 McCaghey, Shao, Kurcezewski, Lindstrom, Ranjan, Whitham, Conley, Williams, Smith and Kabbage.)

Plant diseases caused by necrotrophic fungal pathogens result in large economic losses in field crop production worldwide. Effectors are important players of plant-pathogen interaction and deployed by pathogens to facilitate plant colonization and nutrient acquisition. Compared to biotrophic and hemibiotrophic fungal pathogens, effector biology is poorly understood for necrotrophic fungal pathogens. Recent bioinformatics advances have accelerated the prediction and discovery of effectors from necrotrophic fungi, and their functional context is currently being clarified. In this review we examine effectors utilized by necrotrophic fungi and hemibiotrophic fungi in the latter stages of disease development, including plant cell death manipulation. We define "effectors" as secreted proteins and other molecules that affect plant physiology in ways that contribute to disease establishment and progression. Studying and understanding the mechanisms of necrotrophic effectors is critical for identifying avenues of genetic intervention that could lead to improved resistance to these pathogens in plants., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Shao, Smith, Kabbage and Roth.)

Diaporthe seed decay can compromise seed quality in soybean [ Glycine max (L.) Merr.] in the warm and humid production areas of the United States during crop maturation. In the current study, 45 isolates of Diaporthe were recovered from seed sampled from soybean fields affected by Diaporthe -associated diseases in eight U.S. states in 2017. The isolates obtained belonged to 10 species of Diaporthe based on morphology and phylogenetic analyses of the internal transcribed spacer, partial translation elongation factor 1-α, and β-tubulin gene sequences. The associated species included D. aspalathi , D. caulivora , D. kongii , D. longicolla , D. sojae , D. ueckerae , D. unshiuensis , and three novel fungi, D. bacilloides , D. flavescens , and D. insulistroma . One isolate each of the 10 species was examined for pathogenicity on seed of cultivar Sava under controlled conditions. Seven days postinoculation, significant differences in the percentages of decayed seeds and seedling necrosis were observed among the isolates and the noninoculated control ( P < 0.0001). While the isolates of D. bacilloides , D. longicolla , and D. ueckerae caused a significantly greater percentage of decayed seeds ( P < 0.0001), the isolate of D. aspalathi caused the greatest seedling necrosis ( P < 0.0001). The observation of new fungi causing Diaporthe seed decay suggests the need for a more comprehensive survey in U.S. soybean producing areas since members of the genus Diaporthe appear to form a complex that causes seed decay.

Random-effect meta-analyses were performed on data from 240 field trials conducted between 2005 and 2018 across nine U.S. states and Ontario, Canada, to quantify the yield response of soybean after application of foliar fungicides at beginning pod (R3) stage. Meta-analysis showed that the overall mean yield response when fungicide was used compared with not applying a fungicide was 2.7% (110 kg/ha). Moderator variables were also investigated and included fungicide group, growing season, planting date, and base yield, which all significantly influenced the yield response. There was also evidence that precipitation from the time of planting to the R3 growth stage influenced yield when fungicide was used ( P = 0.059). Fungicides containing a premix of active ingredients from multiple groups (either two or three ingredients) increased the yield by 3.0% over not applying a fungicide. The highest and lowest yield responses were observed in 2005 and 2007, respectively. Better yield response to fungicides (a 3.0% increase) occurred when soybean crops were planted not later than 21 May and when total precipitation between planting and the R3 application date was above historic averages. Temperatures during the season did not influence the yield response. Yield response to fungicide was higher (a 4.7% increase) in average yield category (no spray control yield 2,878 to 3,758 kg/ha) and then gradually decreased with increasing base yield. Partial economic analyses indicated that use of foliar fungicides is less likely to be profitable when foliar diseases are absent or at low levels.

While fungal biotrophs are dependent on successfully suppressing/subverting host defenses during their interaction with live cells, necrotrophs, due to their lifestyle are often confronted with a suite of toxic metabolites. These include an assortment of plant defense compounds (PDCs) which can demonstrate broad antifungal activity. These PDCs can be either constitutively present in plant tissue or induced in response to infection, but are nevertheless an important obstacle which needs to be overcome for successful pathogenesis. Fungal necrotrophs have developed a number of strategies to achieve this goal, from the direct detoxification of these compounds through enzymatic catalysis and modification, to the active transport of various PDCs to achieve toxin sequestration and efflux. Studies have shown across multiple pathogens that the efficient detoxification of host PDCs is both critical for successful infection and often a determinant factor in pathogen host range. Here, we provide a broad and comparative overview of the various mechanisms for PDC detoxification which have been identified in both fungal necrotrophs and fungal pathogens which depend on detoxification during a necrotrophic phase of infection. Furthermore, the effect that these mechanisms have on fungal host range, metabolism, and disease control will be discussed., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Westrick, Smith and Kabbage.)

Shrimp shell waste obtained from Louisiana Gulf shrimp (Litopenaeus setiferus) was heat-treated at varying temperatures and ground into a powder by ball-milling. The powder was used with and without surface treatment with maleic anhydride or stearic acid to form shrimp shell - polylactic acid (PLA) composite granules by solution processing and mechanical grinding. These granules were used as feedstock for the extrusion of composite filaments. The dataset shows the thermal properties of the shrimp shells and the presence of covalent bonding for surface treatment with maleic anhydride. The thermal properties of the composite granules and the influence of the use of surfactants on the morphology, density, and die swell of the extruded filaments are also collected to assess their use as a manufacturing material., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships which have or could be perceived to have influenced the work reported in this article., (© 2021 The Author(s). Published by Elsevier Inc.)

Development of new additive manufacturing materials often requires the production of several batches of relatively large volumes in order to print and test objects. This can be difficult for many materials that are expensive or difficult to produce in large volumes on the laboratory scale. Bioprinter systems are advantageous in this regard, however, commercial systems are expensive or do not have the ability to use photopolymers. Herein, we outline a Syringe Pump Extruder and Curing System (SPECS) modification for inexpensive filament-based 3D printers which enables the use of standard bioplotter materials and photopolymers. The system is capable of using multiple syringe volumes and needle sizes that can be quickly and easily exchanged. The SPECS modification is demonstrated using a Prusa i3 mk3 fused filament fabrication printer to print several 3D objects and films using stereolithography (SLA) photopolymer resin. Geometric accuracy in the X, Y, and Z directions was ±0.1 mm using a 5 ml syringe, 22-gauge needle, and commercial SLA resin. The SPECS system could be of great benefit for laboratories pursing material development in the area of additive manufacturing., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Author(s).)

Dollar spot is caused by the fungus Clarireedia spp. and is the most economically important disease of golf course turfgrass in temperate regions of the United States. Previous research has demonstrated that nitrogen (N) fertilization may reduce dollar spot severity, but the results have been inconsistent, and the impact of N as part of repeated foliar fertilization applications to golf course putting greens remains unclear. Two independent trials were replicated in Madison, Wisconsin and Glenview, Illinois in the 2015, 2016, and 2017 growing seasons. The objective of the first trial was to evaluate the effect of four different N rates applied as urea (4.9, 9.8, 19.4, and 29.3 kg N/ha applied every 2 weeks) on dollar spot severity, and the objective of the second trial was to evaluate the effect of three N sources (calcium nitrate, ammonium sulfate, and ammonium nitrate applied every 2 weeks) on dollar spot severity. Results from the N rate trial at both locations indicated that only the highest (29.3 kg N/ha) rate consistently reduced dollar spot severity relative to the nontreated control. Nitrogen source had minimal and inconsistent impacts on dollar spot severity based on location and year. Although these results show that meaningful reductions in dollar spot severity can be achieved by manipulating N fertilizer application rates, the rate of N needed for disease suppression may be impractical for most superintendents to apply and result in undesirable nontarget impacts.

In total, 52 uniform field experiments were conducted in Illinois, Indiana, Iowa, Michigan, South Dakota, and Wisconsin in the United States and Ontario, Canada from 2013 to 2017 comparing crop protection products against sudden death syndrome (SDS) of soybean. Data were analyzed using meta-analytic models to summarize the relationship between foliar disease index (FDX) and yield. For each study, correlation and regression analyses were performed separately to determine three effect sizes: Fisher's transformation of correlation coefficients ( Z r ), intercept (β 0 ), and slope (β 1 ). Random- and mixed-effect meta-analyses were used to summarize the effect sizes. Study- and location-specific moderator variables FDX (low < 10% and high ≥ 10%), date of planting (early = prior to 7 May, conventional = 7 to 21 May, and late = after 21 May) cultivar (susceptible and partially resistant to SDS), study location, and growing season were used as fixed effects. The overall mean effect sizes of transformed correlation coefficient [Formula: see text] r was -0.41 and different from zero ( P < 0.001), indicating that yield was negatively correlated with FDX. The [Formula: see text] r was affected by disease level ( P < 0.01) and cultivar ( P = 0.02), with a greater effect at higher disease levels and with susceptible cultivars. The mean [Formula: see text] 0 was 4,121 kg/ha and mean [Formula: see text] 1 was -21 kg/ha/% FDX and were different from zero ( P < 0.01). Results from these data indicate that, for every unit of FDX increase, yield was decreased by 0.5%. Study locations and year affected the [Formula: see text] 0 , whereas none of the moderator variables significantly affected [Formula: see text] 1.

A rise in resistance to current antifungals necessitates strategies to identify alternative sources of effective fungicides. We report the discovery of poacic acid, a potent antifungal compound found in lignocellulosic hydrolysates of grasses. Chemical genomics using Saccharomyces cerevisiae showed that loss of cell wall synthesis and maintenance genes conferred increased sensitivity to poacic acid. Morphological analysis revealed that cells treated with poacic acid behaved similarly to cells treated with other cell wall-targeting drugs and mutants with deletions in genes involved in processes related to cell wall biogenesis. Poacic acid causes rapid cell lysis and is synergistic with caspofungin and fluconazole. The cellular target was identified; poacic acid localized to the cell wall and inhibited β-1,3-glucan synthesis in vivo and in vitro, apparently by directly binding β-1,3-glucan. Through its activity on the glucan layer, poacic acid inhibits growth of the fungi Sclerotinia sclerotiorum and Alternaria solani as well as the oomycete Phytophthora sojae. A single application of poacic acid to leaves infected with the broad-range fungal pathogen S. sclerotiorum substantially reduced lesion development. The discovery of poacic acid as a natural antifungal agent targeting β-1,3-glucan highlights the potential side use of products generated in the processing of renewable biomass toward biofuels as a source of valuable bioactive compounds and further clarifies the nature and mechanism of fermentation inhibitors found in lignocellulosic hydrolysates.

In 2002, world leaders committed, through the Convention on Biological Diversity, to achieve a significant reduction in the rate of biodiversity loss by 2010. We compiled 31 indicators to report on progress toward this target. Most indicators of the state of biodiversity (covering species' population trends, extinction risk, habitat extent and condition, and community composition) showed declines, with no significant recent reductions in rate, whereas indicators of pressures on biodiversity (including resource consumption, invasive alien species, nitrogen pollution, overexploitation, and climate change impacts) showed increases. Despite some local successes and increasing responses (including extent and biodiversity coverage of protected areas, sustainable forest management, policy responses to invasive alien species, and biodiversity-related aid), the rate of biodiversity loss does not appear to be slowing.

Purpose: Propofol is a water-insoluble intravenous anesthetic agent that is actually formulated as a water-in-oil emulsion with known drawbacks such as pain on injection, microorganism growth support and stability. We report on the properties of formulations of propofol in poly (N-vinyl-2-pyrrolidone)-block-poly(D,L-lactide), PVP-PLA, polymeric micelles (Propofol-PM)., Methods: Microbial growth in these formulations was evaluated with Pseudomonas aeruginosa (ATCC 9027), Staphylococcus aureus (ATCC 6538), Escherichia coli (ATCC 25922) and Candida albicans (ATCC 10231). Sleep-recovery studies in female Sprague-Dawley rats, at a dose of 10mg/kg were performed to compare pharmacodynamic profiles of the new Propofol-PM formulations with those of Diprivan, a commercially available lipid based propofol formulation., Results: Growth of microorganisms was not supported in the Propofol-PM formulations tested. No significant differences in times to unconsciousness, awakening, recovery of righting reflex and full recovery were observed between Propofol-PM formulations and Diprivan., Conclusions: Propofol loaded in PVP-PLA micelles (Propofol-PM) is not significantly different in terms of pharmacodynamic but demonstrates no microorganism growth support and improved stability that opens up the door to pain on injection reduction strategy.