Open Access Publications

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Open access publications related to sustainability research.

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Neighborhood disadvantage is associated with working memory and hippocampal volumes among older adults
(Aging, Neuropsychology and Cognition, 2024-04-24) Wright, Regina S.; Allan, Alexa C.; Gamaldo, Alyssa A.; Morgan, Adrienne A.; Lee, Anna K.; Erus, Guray; Davatzikos, Christos; Bygrave, Desirée C.
It is not well understood how neighborhood disadvantage is associated with specific domains of cognitive function and underlying brain health within older adults. Thus, the objective was to examine associations between neighborhood disadvantage, brain health, and cognitive performance, and examine whether associations were more pronounced among women. The study included 136 older adults who underwent cognitive testing and MRI. Neighborhood disadvantage was characterized using the Area Deprivation Index (ADI). Descriptive statistics, bivariate correlations, and multiple regressions were run. Multiple regressions, adjusted for age, sex, education, and depression, showed that higher ADI state rankings (greater disadvantage) were associated with poorer working memory performance (p < .01) and lower hippocampal volumes (p < .01), but not total, frontal, and white matter lesion volumes, nor visual and verbal memory performance. There were no significant sex interactions. Findings suggest that greater neighborhood disadvantage may play a role in working memory and underlying brain structure.
Disruption, adaptation, and maintenance of domestic violence services during the COVID-19 pandemic
(Critical Public Health, 2024-04-18) Horney, Jennifer A.; Pena, Annaliese; Scales, Sarah E.; Fleury-Steiner, Ruth E.; Camphausen, Lauren C.; Miller, Susan L.
COVID-19 disrupted many aspects of domestic violence services including sheltering, in-person advocacy, and access to mental health, visitation, and legal services. Increased demand for services occurred concurrent with the highest levels of pandemic disruptions. Adaptations to many systems and services were made to address survivor’s changing needs. To understand how various aspects of service provision were disrupted during the pandemic, we surveyed a national census of U.S. based domestic violence direct service agencies. Email addresses were collected from online directories and each agency received a link to complete a survey using the online platform Qualtrics. The survey included five sections: services provided; work environment during COVID-19; disruptions caused by COVID-19; personal and organizational disaster preparedness; and demographics. Twenty-two percent of 1,341 agencies responded to the survey. At the start of the pandemic, the most disrupted services were legal and court, sheltering, and mental health/counselling services. Hazard pay, flexible scheduling, and additional information technology support were most frequently mentioned supports provided to mitigate disruptions and support providers and advocates. Disruptions and supports changed over the course of the pandemic. The COVID-19 pandemic disrupted the provision of services and advocacy to victims and survivors of domestic violence. Adaptations were made as new control measures were available (e.g. vaccines) and lessons learned were identified (e.g. successful implementation of virtual legal and court services). Maintaining supportive measures post-pandemic will require continued investment in this chronically underfunded, yet critical, sector and applying lessons learned from COVID-19 related disruptions and adaptations.
A comparative assessment of household power failure coping strategies in three American cities
(Energy Research and Social Science, 2024-05-19) Andresen, Adam X.; Kurtz, Liza C.; Chakalian, Paul M.; Hondula, David M.; Meerow, Sara; Gall, Melanie
Household power outage experiences vary based on outage characteristics and the household's ability to cope with a disruption. While disaster management scholarship has produced methods to predict where the most significant impacts of a hazard may occur, these methods do not anticipate secondary effects, such as those from power outages. This research is necessary as the expected risks associated with power outages will increase in the United States due to climate change, increasing electricity demand, and aging infrastructure. To understand households' power outage experiences, we collected 896 surveys from three cities in the United States: Detroit, MI; Miami, FL; and Phoenix, AZ. Participants were recruited through Amazon's Mechanical Turk (MTurk) service to complete a survey. We hypothesized that racial/ethnic minority groups, specifically non-white households and lower-income households experienced more frequent and prolonged power outages. We also hypothesized that the same groups were more likely to have experienced more significant adverse effects, such as throwing away perishable food and not receiving assistance. We found that non-white households in Phoenix and Detroit were more likely to experience longer outages than white households; however, this association was not present in Miami and was not statistically significant in any city. Income was not a major factor in predicting food waste or assistance received during the longest self-reported outage. Further assessments in varying geographical contexts and more generalizable samples are necessary to increase understanding of how households experience power outages.
Spatiotemporal patterns in habitat use of natal and non-natal adult Atlantic sturgeon in two spawning rivers
(Animal Biotelemetry, 2024-04-24) White, Shannon; Breece, Matthew; Fox, Dewayne; Kazyak, David; Higgs, Amanda; Park, Ian; Busch, Cassia; Lubinski, Barbara; Johnson, Robin; Welsh, Amy
Background Monitoring movement across an organism’s ontogeny is often challenging, particularly for long-lived or wide-ranging species. When empirical data are unavailable, general knowledge about species’ ecology may be used to make assumptions about habitat use across space or time. However, inferences about habitat use based on population-level ecology may overlook important eco-evolutionary contributions from individuals with heterogenous ethologies and could diminish the efficacy of conservation and management. Methods We analyzed over a decade of acoustic telemetry data to understand individual differences in habitat use of federally endangered adult Atlantic sturgeon (Acipenser o. oxyrinchus) in the Delaware and Hudson rivers during spawning season. In particular, we sought to understand whether sex or natal origin could predict patterns in habitat use, as there is a long-held assumption that adult Atlantic sturgeon seldom stray into non-natal rivers. Results In both rivers, migration timing, spawning habitat occupancy, and maximum upstream migration distance were similar between natal and non-natal individuals. While non-natal individuals represented only 13% of fish detected in the Hudson River, nearly half of all tagged fish detected in the Delaware River were non-natal and generally occupied freshwater habitats longer than natal individuals. In both systems males had more heterogenous patterns of habitat use and longer duration of occupancy than did females. Conclusions This study demonstrates the importance of non-natal rivers for fulfilling ontogenetic habitat requirements in Atlantic sturgeon. Our results may also highlight an opportunity to improve conservation and management by extending habitat designations to account for more heterogenous patterns in individual habitat use in non-natal freshwater environments.
Living, learning, working, and playing during COVID-19: tackling existing and exacerbated problems of low-income Singaporean youth
(Asia Pacific Journal of Social Work and Development, 2024-02-12) Kwan, Jin Yao; Tan, Joshua; Yi Jie, Chua; Khor, Joanna
COVID-19’s adverse, disproportionate impact on low-income youth — prompting youth-serving professionals to adapt and adjust — is well-documented. However, research gaps exist, including explanatory processes underlying COVID-19’s deleterious impact, systematic documentation of existing and exacerbated problems, and short- and long-term responses of youth-serving professionals. Using a multi-informant mixed methods design guided by a live-learn-work-play theoretical framework, exploratory findings indicated that COVID-19 worsened existing problems across all domains. In the short-term, Singaporean professionals prioritised, moved online, and evaluated programmes. Progressively, they sought to build youth communities, empower families, collaborate, and experiment. Findings have implications for understanding and resolving structural problems perpetuating pre-disaster vulnerabilities.
Evolving wildlife management cultures of governance through Indigenous Knowledges and perspectives
(The Journal of Wildlife Management, 2024-04-17) Fisk, Jonathan James; Leong, Kirsten Mya; Berl, Richard E. W.; Long, Jonathan W.; Landon, Adam C.; Adams, Melinda M.; Hankins, Don L.; Williams, Christopher K.; Lake, Frank K.; Salerno, Jonathan
Within governance agencies, academia, and communities alike, there are increasing calls to recognize the value and importance of culture within social-ecological systems and to better implement Indigenous sciences in research, policy, and management. Efforts thus far have raised questions about the best ethical practices to do so. Engaging with plural worldviews and perspectives on their own terms reflects cultural evolutionary processes driving paradigm shifts in 3 fundamental areas of natural resource management: conceptualizations of natural resources and ecosystems, processes of public participation and governance, and relationships with Indigenous Peoples and communities with differing worldviews. We broadly describe evolution toward these paradigm shifts in fish and wildlife management. We then use 3 case studies to illustrate the ongoing cultural evolution of relationships between wildlife management and Indigenous practices within specific historical and social-ecological contexts and reflect on common barriers to appropriately engaging with Indigenous paradigms and lifeways. Our case studies highlight 3 priorities that can assist the field of wildlife management in achieving the changes necessary to bridge incommensurable worldviews: acknowledging and reconciling historical legacies and their continued power dynamics as part of social-ecological systems, establishing governance arrangements that move beyond attempts to extract cultural information from communities to integrate Indigenous Knowledges into dominant management paradigms, and engaging in critical reflexivity and reciprocal, accountable relationship building. Implementing these changes will take time and a commitment to processes that may initially feel uncomfortable and unfamiliar but have potential to be transformative. Ethical and culturally appropriate methods to include plural and multivocal perspectives and worldviews on their own terms are needed to transform wildlife management to achieve more effective and just management outcomes for all.
Assessing relationships of cover crop biomass and nitrogen content to multispectral imagery
(Agronomy Journal, 2024-02-29) Miller, Jarrod O.; Shober, Amy L.; Taraila, Jamie
Cover 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. Abbreviations DSM digital surface model GDD growing degree days NDRE normalized difference red edge index NDVI normalized difference vegetation index
A recreation demand model for warmwater fishing in Delaware with welfare effects for improvements in catch rates, species diversity, and water clarity
(Agricultural and Resource Economics Review, 2024-03-18) Dalvand, Kaveh; Parsons, George
We estimate a recreation demand model for warmwater fishing in Delaware and then use it to measure welfare gains associated with improved fishing quality as measured by catch rate of fish, diversity of species, and clarity of water. We use a “linked” site choice – trip frequency model with data gathered by the Delaware Division of Fish and Wildlife. Our site choice model includes 118 rivers and lakes in the state with detailed characteristics of each. We develop hypothetical scenarios of fishing quality improvement involving combinations of fish catch, fish diversity, and water clarity and apply it to individual water bodies, water basins, selected water body groupings, and statewide. Values are reported in seasonal per angler and aggregate terms.
Common ragweed (Ambrosia artemisiifolia L.) accessions in the Mid-Atlantic region resistant to ALS-, PPO-, and EPSPS-inhibiting herbicides
(Weed Technology, 2024-03-08) D’Amico Jr. , Frank; Besanҫon, Thierry; Koehler, Alyssa; Shergill, Lovreet; Ziegler, Melissa; VanGessel, Mark
Common ragweed is a troublesome weed in many crops. Farmers and crop advisors in the coastal Mid-Atlantic region have reported inadequate control of common ragweed in soybean fields with glyphosate and other herbicide modes of action. To determine whether herbicide resistance was one of the causes of poor herbicide performance, 29 accessions from four states (Delaware, Maryland, New Jersey, and Virginia) where common ragweed plants survived herbicide applications and produced viable seeds were used for greenhouse screening. Common ragweed seedlings from those accessions were treated with multiple rates of cloransulam, fomesafen, or glyphosate, applied individually postemergence (POST). All accessions except one demonstrated resistance to at least one of the herbicides applied at twice the effective rate (2×), 17 accessions were two-way resistant (to glyphosate and cloransulam, or to glyphosate and fomesafen), and three-way resistance was present in eight accessions collected from three different states. Based on the POST study, five accessions were treated preemergence (PRE) with herbicides that inhibit acetolactate synthase (ALS), and two accessions were treated with herbicides that inhibit protoporphyrinogen oxidase (PPO). All accessions treated PRE with the ALS inhibitors chlorimuron or cloransulam demonstrated resistance at the 2× rates. Both accessions treated PRE with the PPO inhibitor sulfentrazone had survivors at the 2× rate. When the same accessions were treated PRE with fomesafen, one had survivors at the 2× rate, and one had survivors at the 1× rate. Results from these tests confirmed common ragweed with three-way resistance to POST herbicides is widespread in the region. In addition, this is the first confirmation that common ragweed accessions in the region are also resistant to ALS- or PPO-inhibiting herbicides when applied PRE.
Supporting physical activity adoption through recommender system technology: A pilot study
(Journal of Health Psychology, 2024-04-16) Agans, Jennifer P.; Ma, Fenglong; Schade, Serena; Sciamanna, Christopher
We tested the potential for recommender system technology to provide personalized physical activity (PA) suggestions for inactive young adults with high bodyweight. We developed a recommender system using data from the 2017 Behavioral Risk Factor Surveillance System and assessed interest in using the system among 47 young adults (mean age = 23.0 years; 63.4% female; 65.0% White; mean BMI = 29.4). Eleven of these participants (mean age = 23.6 years; 90.9% female, 63.6% White; average BMI = 28.5) also received a PA recommendation and a follow-up interview. Approximately half of the survey participants were willing to use the recommender system, and participants interested in the recommender system differed from those unwilling to try the system (e.g., more likely to be female, worse self-perceived health). Furthermore, eight of the 11 interviewees tried the PA recommended to them, but had mixed reviews of the system’s accuracy. Although our recommender system requires improvements, such systems have promise for supporting PA adoption.
Contrasting roles of rice root iron plaque in retention and plant uptake of silicon, phosphorus, arsenic, and selenium in diverse paddy soils
(Plant and Soil, 2024-02-20) Linam, Franklin A.; Limmer, Matt A.; Seyfferth, Angelia L.
Background and aims Iron (Fe) plaque on rice roots is a mixture of Fe oxide and oxyhydroxide minerals thought to protect rice from high levels of arsenic (As) in flooded paddy soils. Silicon (Si), phosphorus (P), and selenium (Se) also exist as oxyanions in rice paddies, but the impacts of Fe plaque on uptake of these nutrients are unknown. Methods We used natural variation in paddy soil chemistry to test how Si, P, As, and Se move from porewater to plaque to plant via multiple techniques. In a pot study, we monitored Fe plaque deposition and porewater chemistry in 5 different soils over time and measured plaque/plant chemistry and Fe plaque mineralogy at harvest. We normalized oxyanion concentrations by Fe to determine the preferential retention on plaque or plant uptake. Results Low phosphorus availability increased root Fe-oxidizing activity, while Fe, Si, P, As, and Se concentrations in plaque were strongly correlated with porewater. Plaque did not appreciably retain Si and Se, and the oxyanions did not compete for adsorption sites on the Fe plaque. Conclusion Root Fe plaque seems to protect rice from As uptake, does not interfere with Si and Se uptake, and roots adapt to maintain P nutrition even with retention of porewater P on plaque.
Environmental drivers of biogeography and community structure in a Mid-Atlantic estuary
(Oecologia, 2024-02-14) Oleynik, Haley A.; Bizzarro, Joseph J.; Hale, Edward A.; Carlisle, Aaron B.
Estuaries include some of the most productive yet anthropogenically impacted marine ecosystems on the planet, and provide critical habitat to many ecologically and economically important marine species. In order to elucidate ecological function in estuaries, we must understand what factors drive community dynamics. Delaware Bay is the third largest estuary in the United States and hosts over 200 species of migrant and resident fishes and invertebrates. The Delaware Division of Fish and Wildlife has conducted two long-term trawl surveys at monthly intervals in Delaware Bay since 1966. The two surveys collect data on environmental conditions, species composition, and number of fishes and macroinvertebrates across different size classes and life histories. Using a suite of multivariate approaches including hierarchical cluster analysis, canonical correlation analysis, and permutational multivariate analysis of variance, we characterized the fish and macroinvertebrate community in Delaware Bay and found that community composition and environmental conditions varied across spatial and seasonal scales. We identified four distinct biogeographic regions, based on environmental conditions and community composition, which were consistent across surveys. We found that the community was driven primarily by gradients in temperature and salinity and that abundant, frequently occurring species in the Bay have well-defined environmental associations. Our work represents the first attempt to use an existing historical survey to better understand how environmental parameters influence diversity and distribution of macrofauna within Delaware Bay, providing insight into how abiotic variables, influenced by climate, may impact the Delaware Bay ecosystem and similar estuarine ecosystems worldwide.
Early-season biomass and weather enable robust cereal rye cover crop biomass predictions
(Agricultural & Environmental Letters, 2024-02-13) Huddell, Alexandra; Needelman, Brian; Law, Eugene P.; Ackroyd, Victoria J.; Bagavathiannan, Muthukumar V.; Bradley, Kevin; Davis, Adam S.; Evans, Jeffery A.; Everman, Wesley Jay; Flessner, Michael; Jordan, Nicholas; Schwartz-Lazaro, Lauren M.; Leon, Ramon G.; Lindquist, John; Norsworthy, Jason K.; Shergill, Lovreet S.; VanGessel, Mark; Mirsky, Steven B.
Farmers need accurate estimates of winter cover crop biomass to make informed decisions on termination timing or to estimate potential release of nitrogen from cover crop residues to subsequent cash crops. Utilizing data from an extensive experiment across 11 states from 2016 to 2020, this study explores the most reliable predictors for determining cereal rye cover crop biomass at the time of termination. Our findings demonstrate a strong relationship between early-season and late-season cover crop biomass. Employing a random forest model, we predicted late-season cereal rye biomass with a margin of error of approximately 1,000 kg ha−1 based on early-season biomass, growing degree days, cereal rye planting and termination dates, photosynthetically active radiation, precipitation, and site coordinates as predictors. Our results suggest that similar modeling approaches could be combined with remotely sensed early-season biomass estimations to improve the accuracy of predicting winter cover crop biomass at termination for decision support tools. Core Ideas - Cereal rye winter cover crop biomass modeled on data from 35 site-years. - We found a strong relationship between early and late-season biomass. - Random forest model with early-season biomass and weather data performed well. - Similar approach could improve decision support tools for cover crop management. Graphical Abstract available at: https://doi.org/10.1002/ael2.20121 Effect size estimates from the generalized linear mixed effects model prediction late-season cereal rye cover crop biomass. All covariates were standardized, and significant relationships are indicated by *p < 0.05, **p < 0.01, and ***p < 0.001. Abbreviations CGDD cumulative growing degree days GLMM generalized linear mixed effects model PAR photosynthetically active radiation
Post-harvest drone flights to measure weed growth and yield associations
(Agricultural & Environmental Letters, 2022-06-14) Miller, Jarrod O.; Shober, Amy L.; VanGessel, Mark J.
Drone flights are often only performed during the growing season, with no data collected once harvest has been completed, although they could be used to measure winter annual weed growth. Using a drone mounted with a multispectral sensor, we flew small plot corn (Zea mays L.) fertility, cover crop, and population studies at black layer and 0–14 d after harvest (DAH). Yields had positive correlations to normalized difference vegetation index (NDVI) at black layer but often had negative correlations to corn yields 0–14 DAH. After harvest, NDVI could be associated with weed growth, and negative correlations to yield could point to reduced corn canopy allowing light to reach late-season weeds. In fertility studies, excess nitrogen appears to increase weed biomass after harvest, which can be easily identified through drone imagery. Flights should be performed after corn harvest as weed growth may provide additional insight into management decisions. Core Ideas: - Corn yields can be correlated to post-harvest weed biomass by using NDVI. - Drone flights efficiently mapped weeds and made correlations to yield and management. - Fall weed control can be prioritized using drone mapping. Abbreviations: DAH days after harvest LAI leaf area index NDVI normalized difference vegetation index
Monitoring winter wheat growth at different heights using aerial imagery
(Agronomy Journal, 2021-02-09) Miller, Jarrod O.; Adkins, James
Drones (unmanned aerial vehicles) provide another system to mount sensors for measuring plant characteristics. For winter wheat (Triticum aestivum) this can include evaluating stands and making nitrogen (N) recommendations. Timing these flights and adequate camera resolution (based on flying height), must be known before applying tasks. This study observed six winter wheat planting populations (222, 297, 371, 445, 494, and 544 seeds m–2) at three different heights above ground level (30, 60, and 120 m) over three growing seasons. Plant populations could be separated at all growth stages and heights flown but were easier to separate right after emergence (GS11). In the spring, additional tillering caused the higher populations (371–544 seeds m–2) to have similar normalized difference vegetative index (NDVI), much like the final yields. Comparing changes in NDVI between flights was also successful in separating high and low planting populations, with inverse relationships in the fall and spring. A random forest classification of tiller counts by NDVI measurements ranked change in NDVI between stages as the most important compared to single flights. As separation and classification was successful at the lowest camera resolution (120 m), it can be possible for scouts to collect whole field imagery for analyses prior to deciding on split N applications.
Sensor-based measurements of NDVI in small grain and corn fields by tractor, drone, and satellite platforms
(Crop and Environment, 2024-02-01) Miller, Jarrod O.; Mondal, Pinki; Sarupria, Manan
The use of sensors for variable rate nitrogen (VRN) applications is transitioning from equipment-based to drone and satellite technologies. However, regional algorithms, initially designed for proximal active sensors, require evaluation for compatibility with remotely sensed reflectance and N-rate predictions. This study observed normalized difference vegetation index (NDVI) data from six small grain and two corn fields over three years. We employed three platforms: tractor-mounted active sensors (T-NDVI), passive multispectral drone (D-NDVI), and satellite (S-NDVI) sensors. Averaged NDVI values were extracted from the as-applied equipment polygons. Correlations between NDVI values from the three platforms were positive and strong, with D-NDVI consistently recording the highest values, particularly in areas with lower plant biomass. This was attributed to D-NDVI's lower soil reflectance and its ability to measure the entire biomass within equipment polygons. For small grains, sensors spaced on equipment booms might not capture accurate biomass in poor-growing and low NDVI regions. Regarding VRN, S-NDVI and D-NDVI occasionally aligned with T-NDVI recommendations but often suggested half the active sensor rate. Final yields showed some correlation with landscape variables, irrespective of N application. This finding suggests the potential use of drone or satellite imagery to provide multiple NDVI maps before application, incorporating expected landscape responses and thereby enhancing VRN effectiveness.
Profiling national institutional archetypes for climate change technology implementation: application in small islands and least developed countries
(Mitigation and Adaptation Strategies for Global Change, 2024-04-19) Shah, Kalim U.
In developing countries, when the implementation success of new climate adaptation and mitigation technologies fall short of expectations, the typical “suspects” cited are lack of funding or country expertise and allusions to “lack of institutional capacity.” The premise of this study is that the national institutional environment is the fundamental prerequisite for successful technology implementation, and despite much effort, a diagnostic approach to assessing this prerequisite is missing. Here, I propose an approach to do this, based on an understanding of the dynamics that interconnect country-level legal, regulatory and market mechanisms, societal norms, and inter/intra governmental structures. I estimate levels of country structural and systems supports, operating environment, implementer acceptance and country tractability. A preliminary test of the approach was completed through a survey of experts involved in the United Nations Technology Needs Assessment programs in Least Developed and Small Island Developing Countries. It was found that countries fall into four fundamental archetypes. A country’s archetype suggests characteristics of the institutional environment that help to explain the potential for technology implementation success. A further implication is that some countries that typically would not be considered very similar may possess similar country institutional environments. One consequence of this is that archetype-based groups could work together and learn from each other more effectively.
How manganese affects rice cadmium uptake and translocation in vegetative and mature plants
(Plant and Soil, 2024-04-19) Hu, Ruifang; Limmer, Matthew A.; Seyfferth, Angelia L.
Background and aims Rice is prone to Cd uptake under aerobic soil conditions primarily due to the OsNramp5 Mn transport pathway. Unlike Cd, Mn availability in rice paddies decreases as redox potential increases. We tested whether increasing Mn concentrations in solution would decrease Cd accumulation in rice through competition between Mn and Cd for uptake and/or suppression of OsNramp5 expression. Methods Rice was grown to maturity under Mn concentrations that spanned three orders of magnitude (0.30 to 37 μM) that corresponded to free Mn2+ activities of 10–7.9 to 10–5.0 M while free Cd2+ activity was held as constant as achievable (10–10.2 to 10–10.4 M). Plant biomass and elemental concentrations were measured in roots and shoots at each stage. Fold changes in the expression of OsNramp5, OsCd1, OsHMA3, OsCCX2, and OsYSL6 genes in vegetative and grain-filling stages of rice plants were determined. Results Competition between Mn and Cd for root uptake and accumulation in shoots was observed at the highest concentration of Mn tested. OsNramp5 expression was significantly higher in rice plants at the vegetative stage compared to the grain-filling stage, while OsCd1 and OsHMA3 showed the opposite. Solution Mn concentrations previously thought to be tolerable by rice grown to the vegetative stage led to Mn toxicity as plants matured. Conclusions Mn competes with Cd during uptake into rice with OsNramp5 expression unaffected. Different translocation paths may occur for Mn and Cd within the rice plant and over the rice life cycle, with OsCCX2 correlated with shoot Cd concentration.
Moths are less attracted to light traps than they used to be
(Journal of Insect Conservation, 2024-04-19) Battles, Ian; Burkness, Eric; Crossley, Michael S.; Edwards, Collin B.; Holmstrom, Kristian; Hutchison, William; Ingerson-Mahar, Joseph; Owens, David; Owens, Avalon C.S.
As evidence of global insect declines continues to mount, insect conservationists are becoming increasingly interested in modeling the demographic history of at-risk species from long-term survey data. However, certain entomological survey methods may be susceptible to temporal biases that will complicate these efforts. Entomological light traps, in particular, may catch fewer insects today than they once did due solely to increases in anthropogenic light pollution. Here we investigate this possibility by comparing the demographic histories of corn earworm moths (Helicoverpa zea) estimated from pairs of blacklight and pheromone traps monitored at the same farms. We find a stark decline in blacklight trap efficacy over 25 years of monitoring in Delaware, USA, mirrored over 10 years of monitoring in New Jersey, USA. While the precise causes of this decline remain a subject for discussion, the practical consequences are clear: insect conservationists cannot fully rely on long-term trends from entomological light traps.
A Bacillus velezensis strain shows antimicrobial activity against soilborne and foliar fungi and oomycetes
(Frontiers in Fungal Biology, 2024-02-23) Wockenfuss, Anna; Chan, Kevin; Cooper, Jessica G.; Chaya, Timothy; Mauriello, Megan A.; Yannarell, Sarah M.; Maresca, Julia A.; Donofrio, Nicole M.
Biological control uses naturally occurring antagonists such as bacteria or fungi for environmentally friendly control of plant pathogens. Bacillus spp. have been used for biocontrol of numerous plant and insect pests and are well-known to synthesize a variety of bioactive secondary metabolites. We hypothesized that bacteria isolated from agricultural soil would be effective antagonists of soilborne fungal pathogens. Here, we show that the Delaware soil isolate Bacillus velezensis strain S4 has in vitro activity against soilborne and foliar plant pathogenic fungi, including two with a large host range, and one oomycete. Further, this strain shows putative protease and cellulase activity, consistent with our prior finding that the genome of this organism is highly enriched in antifungal and antimicrobial biosynthetic gene clusters. We demonstrate that this bacterium causes changes to the fungal and oomycete hyphae at the inhibition zone, with some of the hyphae forming bubble-like structures and irregular branching. We tested strain S4 against Magnaporthe oryzae spores, which typically form germ tubes and penetration structures called appressoria, on the surface of the leaf. Our results suggest that after 12 hours of incubation with the bacterium, fungal spores form germ tubes, but instead of producing appressoria, they appear to form rounded, bubble-like structures. Future work will investigate whether a single antifungal molecule induces all these effects, or if they are the result of a combination of bacterially produced antimicrobials.

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