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A rulebook for peptide control of legume–microbe endosymbioses
Get PDFPlants engage in mutually beneficial relationships with microbes, such as arbuscular mycorrhizal fungi or nitrogen-fixing rhizobia, for optimized nutrient acquisition. In return, the microbial symbionts receive photosynthetic carbon from the plant. Both symbioses are regulated by the plant nutrient status, indicating the existence of signaling pathways that allow the host to fine-tune its interactions with the beneficial microbes depending on its nutrient requirements. Peptide hormones coordinate a plethora of developmental and physiological processes and, recently, various peptide families have gained special attention as systemic and local regulators of plant–microbe interactions and nutrient homeostasis. In this review, we identify five \u27rules\u27 or guiding principles that govern peptide function during symbiotic plant–microbe interactions, and highlight possible points of integration with nutrient acquisition pathways
Effect of winter canola cultivar on seed yield, oil, and protein content
Get PDFWinter canola (Brassica napus L.) production has increased in the United States over the past several decades; however, there is little research in the southeastern United States on its agronomic production and growth characteristics under different nitrogen (N) fertilizer rates. The objectives of this study were to determine the effects of N rates on winter mortality, yield, oil and protein content, and seedpod shatter resistance across cultivars. Canola was grown in a randomized split complete block design with four replicates under five different N rates (0, 56, 112, 168, and 224 kg N ha−1) with four different cultivars (Hekip, Inspiration, and Edimax CL or Phoenix CL). Seed yield was very low for the 2017–2018 season, likely due to extreme cold conditions in winter and/or frost at flowering. There was high winter mortality during this period, but Edimax CL had significantly lower mortality (79.7%) than Inspiration (85.7%) and Hekip (83.9%). In the following year, more mild temperatures led to low mortality and greater yields, where rates of 112, 168, and 224 kg N ha−1 had the greatest yields (1,612–1,857 kg ha−1) with no significant differences according to cultivar. In 2018, shatter resistance was greatest for the rates of 112, 168, and 224 kg N ha−1 and was positively related to N rate. Across both years, Inspiration had greater shatter resistance. In 2019, the lowest N rate (0 kg N ha−1) and Phoenix CL had significantly greater oil contents (48.4 and 47.3%, respectively), whereas the highest N rate (224 kg N ha−1) with no particular cultivar had a significantly greater protein content (21.0%)
The Current State of Community Engagement in Urban Soil Pollution Science
Get PDFEnvironmental burdens disproportionately impact the health of communities of color and low-income communities. Contemporary and legacy industry and land development may pollute soils with pesticides, petroleum products, and trace metals that can directly and indirectly impact the health of frontline communities. Past efforts to study environmental injustice have often excluded those most impacted, created distrust of researchers and other experts among frontline communities, and resulted in little to no structural change. Prevailing research methods value formal knowledge systems, while often dismissing the knowledge of those most harmed by environmental hazards. Community science has emerged as a process of doing science that centers the participation of community members, who may co-develop research questions, inform study methods, collect data, interpret findings, or implement projects. While community science is one of several research methods that can advance community goals, it can also be implemented in ways that are extractive or harm communities. Research on best practices for community science is robust; however, how community science has been used in urban soil research is not well understood. We identified sixteen relevant urban soil studies published between 2008 and 2021 that used community science methods or engaged with community members around soil pollution. We then assessed the selected studies using two community engagement models to better understand community engagement practices in urban soil pollution science. The Spectrum of Community Engagement to Ownership (SCEO) model, which organizes engagement from level 0 (ignore) to 5 (defer to) was used to assess all studies. Studies that explicitly aimed to co-develop research with the community were additionally assessed using the Urban Sustainability Directors Network High Impact Practices (USDN HIPs). The majority of the studies assessed were aligned with levels 1–3 of the SCEO. Studies assessed as levels 4–5 of the SCEO were associated with delegating power to communities, community engages decision-making, creating space for community voices, and remediation efforts. We propose that future urban remediation soil pollution work that engages at higher levels of the SCEO and employs USDN HIPs, will be more effective at addressing crucial environmental health challenges by supporting, equitable, inclusive, and sustainable solutions
Electrospray Deposition of Polyvinylidene Fluoride (PVDF) Microparticles: Impact of Solvents and Flow Rate
Get PDFPolymeric microparticles have been shown to have great impacts in the area of drug delivery, biosensing, and tissue engineering. Electrospray technology, which provides a simple yet effective technique in the creation of microparticles, was utilized in this work. In addition, altering the electrospray experimental parameters such as applied voltage, flow rate, collector distance, solvents, and the polymer-solvent mixtures can result in differences in the size and morphology of the produced microparticles. The effects of the flow rate at (0.15, 0.3, 0.45, 0.6, 0.8, and 1 mL/h) and N, N-Dimethylformamide (DMF)/acetone solvent ratios (20:80, 40:60, 60:40, 80:20, 100:0 v/v) in the production of polyvinylidene fluoride (PVDF) microparticles were studied. Scanning electron microscopy (SEM) was used to observe changes in the morphology of the microparticles, and this revealed that a higher acetone to DMF ratio produces deformed particles, while flow rates at (0.3 and 0.45 mL/h) and a more optimized DMF to acetone solvent ratio (60:40 v/v) produced uniform spherical particles. We discovered from the Raman spectroscopy results that the electrosprayed PVDF microparticles had an increase in piezoelectric β phase compared to the PVDF pellet used in making the microparticles, which in its original form is α phase dominant and non-piezoelectric
Efficacy and Timing of Application of Fungicides, Biofungicides, Host-Plant Defense Inducers, and Fertilizer to Control Phytophthora Root Rot of Flowering Dogwoods in Simulated Flooding Conditions in Container Production
Get PDFPhytophthora root rot caused by Phytophthora cinnamomi Rands is one of the major diseases of flowering dogwoods (Cornus florida L.). The severity of root rot disease increases when the plants are exposed to flooding conditions. A study was conducted to determine the efficacy and timing of application of different fungicides, biofungicides, host plant defense inducers, and fertilizer to manage Phytophthora root rot in month-old seedlings in simulated flooding events for 1-, 3-, and 7- days. Preventative treatments were drench applied 3 weeks and 1 week before flooding whereas curative treatments were applied 24 hrs. after flooding. Dogwood seedlings were inoculated with P. cinnamomi 3 days before the flooding. Plant height and width were recorded at the beginning and end of the study. At the end of the study, plant total weight and root weight were recorded and disease severity in the root was assessed using a scale of 0-100%. Root samples were plated using PARPH-V8 medium to determine the percentage recovery of the pathogen. Empress Intrinsic, Pageant Intrinsic, Segovis, and Subdue MAXX, as preventative and curative applications, were able to suppress the disease severity compared to the inoculated control in all flooding durations. All treatments, with the exception of Stargus as preventative application 3 weeks before flooding and Orkestra Intrinsic as curative application, were able to suppress the disease severity compared to the inoculated control for 1-day flooding event. Aliette and ON-Gard were effective in the first trial when applied preventatively in both 1 week and 3 weeks before flooding but not in the second trial. Signature Xtra was effective as preventative application but not as a curative application. Interface was effective as curative application but not as preventative application. The findings of this study will help nursery growers to understand the performance of fungicides, biofungicides, host-plant defense inducers, and fertilizer in different time intervals and repeated applications to manage Phytophthora root rot in flooding conditions
Agritourism as an Alternative On-Farm Enterprise for Small U.S. Farms: Examining Factors Influencing the Agritourism Decisions of Small Farms
Get PDFThis study examines the adoption of agritourism by small farms in the U.S. Using primary survey data collected from small farms in Tennessee in 2020, we assessed adopter characteristics and investigated the factors influencing the farmers’ decision to adopt or add agritourism-related activities, including recreational, educational, and touristic attractions in the farm. We found that factors such as social media marketing, smartphone use in farm activities, and having farm insurance significantly increased the likelihood of agritourism adoption in addition to other demographic factors. Additionally, we found that a farmer’s perceived survival risk positively influences small farms to adopt agritourism. Small farms with survival challenges in the U.S. could consider agritourism as an enterprise to enhance their economic sustainability by utilizing touristic aspects of farming, rural landscape, and agriculture
Cognitive and Non-Cognitive Pre-College Predictor’s Impact on College Graduation
No full textThis study assesses the impact of cognitive and noncognitive pre-characteristics on college graduation in Tennessee. The State of Tennessee has applied multiple campus-based interventions at the Tennessee Board of Regents and the University System of Tennessee to increase graduation rates. This study is driven by three concepts and investigated by two main research questions: (1) To what extent do cognitive and non-cognitive pre-college experiences college impact a student’s propensity to graduate college at a mid-sized public university? (2) What cognitive/non-cognitive pre-college characteristics impact a student’s propensity to graduate college at a mid-sized public university? While cognitive and non-cognitive factors impacting college graduation are relatively new research areas, this study aims to add to the literature by measuring the extent. The null Hypotheses explored the negative significance of impact and extent on college graduation. Vincent Tinto has pioneered and steered the area of student retention for nearly five decades. Evolving models of Astin’s 1980 Involvement Model or, more recently, Swails’ 2004 Student-Centered Model, student retention remains an area of interest for colleges and universities, families, and public officials. This examination included descriptive statistics for variable exploration and Binary Logistic Regression Analysis for the overall model and significance. The results found significance in five of the cognitive and one of the non-cognitive variables selected with a positive-to-very positive impact on college graduation. Contrary to the researcher’s previous belief, non-cognitive variables could not reject the null hypothesis but encourage additional research by utilizing diverse and relevant variables
Grow Your Own: Recommendations for Addressing Teacher Shortages for STEM and Other Critical Needs Areas
Get PDFThe United States has a well-documented teacher shortage crisis. Areas such as Science, Technology, Engineering and Mathematics (STEM) continue to experience shortages. Since teachers have the greatest impact on student achievement, the lack of highly qualified teachers potentially affects the academic and economic stability of the United States. This paper provides model recommendations for addressing teacher shortages in STEM and other critical shortage areas. These recommendations can be implemented at the local, district, state or national levels. Utilization of the models can potentially influence student achievement, human resource—talent acquisition, teacher preparation, policy development and professional development