Evaluation of a Peroxide-Based Algaecide for Cyanobacteria Control: A Mesocosm Trial in Lake Okeechobee, FL, USA

A 72 h small-scale trial was conducted in enclosed mesocosms in the Lake Okeechobee waterway to evaluate the effectiveness of a USEPA-registered peroxide-based algaecide (formulated as sodium carbonate peroxyhydrate) for controlling a natural cyanobacteria population. Mesocosms were initially subjected to either no algaecide or the maximum label rate of 10 mg H2O2·L−1. A subset of mesocosms were then subjected to a sequential application of 5 mg H2O2·L−1 at 48 h after initial treatment. Following application, peroxide concentrations rapidly decreased and were undetectable by 48 h. At 24 h after treatment, significant decreases in all biomass indicators were observed (compared to untreated mesocosms), including extracted chlorophyll a, microscopic counts (total phytoplankton and total cyanobacteria), and cyanobacteria-specific 16S rRNA gene copies by over 71%. Although peroxide treatment reduced cyanobacteria biomass, there was no change in overall community structure and the remaining population was still dominated by cyanobacteria (>90%). After 48 h exposure, some biomass recovered in single application mesocosms resulting in only a 32–45% reduction in biomass. Repeated peroxide dosing resulted in the greatest efficacy, which had a sustained (60–91%) decrease in all biomass indicators for the entire study. While a single application of the peroxide was effective in the first 24 h, a sequential treatment is likely necessary to sustain efficacy when using this approach to manage cyanobacteria in the field. Results of this study support that this peroxide-based algaecide is a strong candidate to continue with scalable field trials to assess its potential future utility for operational management programs in the Lake Okeechobee waterway.

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The Growth of Leaf Lettuce and Bacterial Communities in a Closed Aquaponics System with Catfish

Horticulturae ◽

10.3390/horticulturae7080222 ◽

2021 ◽

Vol 7 (8) ◽

pp. 222

Author(s):

Kenji Yamane ◽

Yuuki Kimura ◽

Keita Takahashi ◽

Isamu Maeda ◽

Masayuki Iigo ◽

...

Keyword(s):

Plant Growth ◽

Early Stage ◽

Amplicon Sequencing ◽

Small Scale ◽

Rrna Gene ◽

Culture Solution ◽

Beneficial Effects ◽

Sustainable Cultivation ◽

Microbial Groups ◽

Production Period

Aquaponics is a circulating and sustainable system that combines aquaculture and hydroponics and forms a symbiotic relationship between fish, plants, and microorganisms. We hypothesized that feed alone could support plant growth, but the symbiosis with fish adds some beneficial effects on plant growth in aquaponics. In this study, we created three closed culture systems, namely, aquaponics, hydroponics without nitrogen (N) and phosphorus (P), and aquaculture, and added the same amount of feed containing N and P to all the treatments in order to test the hypothesis. Accumulation of NO3− and PO43− was alleviated in aquaponics and hydroponics as a result of plant uptake. Lettuce plants grown in aquaponics grew vigorously until 2 weeks and contained a constant level of N in plants throughout the production period, whereas those in hydroponics grew slowly in the early stage and then vigorously after 2 weeks with a late increment of N concentration. These results suggest that catfish help with the faster decomposition of the feed, but, in hydroponics, feed can be slowly dissolved and decomposed owing to the absence of the fish. The bacterial community structures of the culture solution were investigated using 16S rRNA gene amplicon sequencing. At the class level, Actinobacteria, Alphaproteobacteria, Betaproteobacteria, and Gammaproteobacteria were the major microbial groups in the solutions. Aquaponics prevented the pollution of tank solution and maintained a higher water quality compared with hydroponics and aquaculture, suggesting that aquaponics is a more sustainable cultivation system even in a small-scale system.

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Control of Helicoverpa zea in Tomatoes with Chlorantraniliprole Applied Through Drip Chemigation

Plant Health Progress ◽

10.1094/php-2009-0407-01-rs ◽

2010 ◽

Vol 11 (1) ◽

pp. 21 ◽

Cited By ~ 11

Author(s):

Thomas P. Kuhar ◽

James F. Walgenbach ◽

Hélène B. Doughty

Keyword(s):

North Carolina ◽

Helicoverpa Zea ◽

Field Trials ◽

Single Application ◽

Beneficial Arthropods ◽

Worker Exposure ◽

Anthranilic Diamide ◽

Mammalian Toxicity ◽

Tomato Fruitworm ◽

Reduced Risk

Chlorantraniliprole (=Rynaxypyr) is a novel anthranilic diamide insecticide that is of interest to vegetable growers because of its low mammalian toxicity and systemic properties. Field trials were conducted between 2006 and 2008 in North Carolina and Virginia to test the efficacy of chlorantraniliprole as a drip chemigation treatment on tomatoes. Drip chemigation of chlorantraniliprole at various rates and intervals significantly reduced the percentage of tomatoes damaged by tomato fruitworm (Helicoverpa zea) comparable to that typically achieved from multiple foliar applications of insecticides. The best control was achieved with two applications of chlorantraniliprole at 0.074 kg ai/ha, or a single application at 0.099 kg ai/ha. Residual ingestion bioassays showed that chlorantraniliprole was effectively taken up by the roots and was active in leaves up to 66 days after treatment (DAT), active in blossoms up to 22 DAT, but was not active in fruit. Drip chemigation of chlorantraniliprole may offer several advantages over foliar applications, including ease of application, reduced pesticide input into the environment, reduced worker exposure to pesticides, and reduced risk to beneficial arthropods. Accepted for publication 14 January 2010. Published 7 April 2010.

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Intragenomic and intraspecific heterogeneity in rrs may surpass interspecific variability in a natural population of Veillonella

Microbiology ◽

10.1099/mic.0.038224-0 ◽

2010 ◽

Vol 156 (7) ◽

pp. 2080-2091 ◽

Cited By ~ 28

Author(s):

Anne-Laure Michon ◽

Fabien Aujoulat ◽

Laurent Roudière ◽

Olivier Soulier ◽

Isabelle Zorgniotti ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Gene Diversity ◽

Natural Populations ◽

Variable Region ◽

Housekeeping Gene ◽

Single Copy ◽

Population Based ◽

Rrna Gene ◽

Gene Copies

As well as intraspecific heterogeneity, intragenomic heterogeneity between 16S rRNA gene copies has been described for a range of bacteria. Due to the wide use of 16S rRNA gene sequence analysis for taxonomy, identification and metagenomics, evaluating the extent of these heterogeneities in natural populations is an essential prerequisite. We investigated inter- and intragenomic 16S rRNA gene heterogeneity of the variable region V3 in a population of 149 clinical isolates of Veillonella spp. of human origin and in 13 type or reference Veillonella strains using PCR-temporal temperature gel electrophoresis (TTGE). 16S rRNA gene diversity was high in the studied population, as 45 different banding patterns were observed. Intragenomic heterogeneity was demonstrated for 110 (74 %) isolates and 8 (61.5 %) type or reference strains displaying two or three different gene copies. Polymorphic nucleotide positions accounted for 0.5–2.5 % of the sequence and were scattered in helices H16 and H17 of the rRNA molecule. Some of them changed the secondary structure of H17. Phylotaxonomic structure of the population based on the single-copy housekeeping gene rpoB was compared with TTGE patterns. The intragenomic V3 heterogeneity, as well as recombination events between strains or isolates of different rpoB clades, impaired the 16S rRNA-based identification for some Veillonella species. Such approaches should be conducted in other bacterial populations to optimize the interpretation of 16S rRNA gene sequences in taxonomy and/or diversity studies.

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Grain mineral density of bread and durum wheat landraces from geochemically diverse native soils

Crop and Pasture Science ◽

10.1071/cp17306 ◽

2018 ◽

Vol 69 (4) ◽

pp. 335 ◽

Cited By ~ 4

Author(s):

José Francisco Vázquez ◽

Efraín Antonio Chacón ◽

José María Carrillo ◽

Elena Benavente

Keyword(s):

Durum Wheat ◽

Triticum Aestivum L ◽

Field Trials ◽

Mineral Elements ◽

Small Scale ◽

Mineral Density ◽

Native Soil ◽

Wide Range ◽

Grain Zinc ◽

Wheat Landraces

Future progress on the creation of wheat cultivars with high grain zinc (Zn) and iron (Fe) mineral density will depend on both the availability of suitable donor germplasm and the identification of genes or quantitative trait loci contributing to increase the accumulation of mineral elements in the wheat kernels. Multi-environment field trials were conducted to evaluate the grain Zn, Fe and protein concentration of 32 bread wheat (Triticum aestivum L.) and 20 durum wheat (T. turgidum L. var. durum) landraces locally adapted to soils covering a wide range of pH values and mineral composition. These landraces were selected after a preliminary, small-scale field trial that had analysed 425 Spanish local varieties. Analyses of variance demonstrated a significant effect of genotype on grain composition, and 16 wheat landraces with elevated grain Zn and/or Fe density across the environments were identified. These landraces rich in grain minerals represent valuable primary gene-pool parents for wheat biofortification. No pattern of native soil geochemical characteristics that could help to predict the success in collecting mineral-dense genotypes in a given area was found. Mapping populations derived from some pairs of grain-mineral-rich and -poor genotypes characterised in the study may facilitate the development of molecular markers to assist the selection of superior wheat genotypes.

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Fungicide efficacy on tar spot and yield of corn in the Midwestern United States

Plant Health Progress ◽

10.1094/php-10-21-0125-rs ◽

2022 ◽

Author(s):

Darcy E. P. Telenko ◽

Martin I. Chilvers ◽

Adam Byrne ◽

Jill Check ◽

Camila Rocco Da Silva ◽

...

Keyword(s):

United States ◽

Growth Stage ◽

Field Trials ◽

Corn Belt ◽

Yield Losses ◽

Single Application ◽

Midwestern United States ◽

Tar Spot ◽

Significant Yield ◽

Foliar Fungicide

Tar spot of corn caused by Phyllachora maydis has recently led to significant yield losses in the eastern corn belt of the Midwestern United States. Foliar fungicides containing quinone outside inhibitors(QoI), demethylation inhibitors(DMI), and succinate dehydrogenase inhibitors(SDHI) are commonly used to manage foliar diseases in corn. To mitigate the losses from tar spot thirteen foliar fungicides containing single or multiple modes of action (MOA/FRAC groups) were applied at their recommended rates in a single application at the standard tassel/silk growth stage timing to evaluate their efficacy against tar spot in a total of eight field trials in Illinois, Indiana, Michigan, and Wisconsin during 2019 and 2020. The single MOA fungicides included either a QoI or DMI. The dual MOA fungicides included a DMI with either a QoI or SDHI, and fungicides containing three MOAs included a QoI, DMI, and SDHI. Tar spot severity estimated as the percentage of leaf area covered by P. maydis stroma of the non-treated control at dent growth stage ranged from 1.6 to 23.3% on the ear leaf. Averaged across eight field trials all foliar fungicide treatments reduced tar spot severity, but only prothioconazole+trifloxystrobin, mefentrifluconazole+pyraclostrobin+fluxapyroxad, and mefentrifluconazole+pyraclostrobin significantly increased yield over the non-treated control. When comparing fungicide treatments by the number of MOAs foliar fungicide products that had two or three MOAs decreased tar spot severity over not treating and products with one MOA. The fungicide group that contained all three MOAs significantly increased yield over not treating with a fungicide or using a single MOA.

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Six species of nontuberculous mycobacteria carry non-identical 16S rRNA gene copies

Journal of Microbiological Methods ◽

10.1016/j.mimet.2018.08.012 ◽

2018 ◽

Vol 155 ◽

pp. 34-36

Author(s):

Keita Takeda ◽

Kinuyo Chikamatsu ◽

Yuriko Igarashi ◽

Yuta Morishige ◽

Yoshiro Murase ◽

...

Keyword(s):

16S Rrna ◽

16S Rrna Gene ◽

Nontuberculous Mycobacteria ◽

Rrna Gene ◽

Gene Copies

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Modifikasi alat cakram untuk proses pembelajaran

Journal of Physical Activity and Sports (JPAS) ◽

10.53869/jpas.v2i2.79 ◽

2021 ◽

Vol 2 (2) ◽

pp. 180-188

Author(s):

Laras Gita Kinanti ◽

Utvi Hinda Zhannisa ◽

Tubagus Herlambang

Keyword(s):

Physical Education ◽

Large Scale ◽

Field Trials ◽

Small Scale ◽

Plate Waste ◽

Education Material ◽

Teachers And Students ◽

Student Questionnaire ◽

Scale Test ◽

Expert Validation

The purpose of this research is to modify a simple disc device for learning physical education. The research method used was the development of Borg & Gall, namely (1) collecting information, (2) developing the initial form (in the form of a disc tool model), (3) expert validation testing, namely using 1 validation of athletic experts and one physical education learning expert, and small-scale trials using questionnaires and analysis, (4) revision of the first product design, based on the results of experts and small-scale trials (20 students), (5) field trials (48 students), (6) final product revision, (7) the final result of the modification produced through revision of field trials.The results of expert validation were carried out by 2 validities, namely validation in the field of athletic experts and validation of physical education material experts, and the results obtained in each validity were the first for the validation results in the field of athletic experts getting a percentage of 87.6% calcification (Good) , the second for the validation results in the field of Physical Education material experts got a percentage of 83.0% with the classification (Good). The results of the student questionnaire on a small scale test got a percentage of 86.6% (good). the results of the questionnaire on large-scale test students got a percentage of 81.8% (good).The conclusion and advice is that the development of a modified model of disc throwing tools with iron plate waste media can be used as an alternative to discus throwing. With the modification of disc throwing, teachers and students can be helped in learning discusses, students are interested and more active and excited in learning throw the disc.

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Pengembangan Komik Matematika Berbasis Kontekstual Untuk Materi Lingkaran

JURNAL PENELITIAN PENDIDIKAN MATEMATIKA DAN SAINS ◽

10.26740/jppms.v3n2.p55-64 ◽

2021 ◽

Vol 3 (2) ◽

pp. 55

Author(s):

Elfrida Rif’atul Chusniah ◽

Rini Setianingsih

Keyword(s):

Research And Development ◽

Teaching And Learning ◽

Field Trials ◽

Student Response ◽

Quality Of Education ◽

Small Scale ◽

Maximum Score ◽

Is Research ◽

Scale Field

Penelitian ini adalah penelitian yang bertujuan untuk mengembangkan komik matematika berbasis kontekstual untuk materi lingkaran yang berkualitas baik berdasarkan tiga kriteria, yaitu valid, praktis, dan efektif. Rancangan penelitian ini adalah Research and Development (R&D). Prosedur-prosedur pengembangan yang digunakan meliputi empat langkah: (1) melakukan perencanaan produk yang akandikembangkan, (2) mengembangkan produk awal, (3) validasi dan revisi produk, (4) uji coba lapangan skala kecil dan revisi. Uji coba komik dilakukan secara terbatas oleh 10 siswa kelas VIII SMP. Teknik pengumpulan data yang diterapkan dalam penelitian ini adalah angket, sedangkan instrumen penelitian yangdigunakan meliputi lembar validasi, angket penggunaan media, dan angket respon siswa. Data penelitian dianalisis dengan deskriptif kualitatif. Hasil penelitian ini menunjukkan bahwa komik matematika dinyatakan valid dengan skor kevalidan 4 oleh ahli media dan 3,9 oleh ahli materi dari skor maksimum 5 sehingga dikategorikan valid, komik matematika dinyatakan praktis dengan hasil analisis persentase kepraktisan 76,28 % dan komik matematika dinyatakan efektif degan hasil analisis persentase keefektifan 79,4%, sehingga dikategorikan efektif. Berdasarkan hasil tersebut maka media komik ini memiliki kualitas yang baik sehingga dapat dimanfaatkan sebagai satu upaya atau alternatif media dalam proses pembelajaran sebagai upaya peningkatan kualitas pendidikan dan menciptakan suasana yang menyenangkan bagi siswa.Kata Kunci: media pembelajaran, komik matematika, lingkaranThis research is a research that aims to develop contextual based mathematical comics for good quality circle material based on three criteria, namely valid, practical, and effective. The design of this research is Research and Development (R&D). The development procedures used include four steps: (1) conducting product planning to be developed, (2) developing initial products, (3) product validation and revision, (4) small-scale field trials and revisions. Comic trials are limited to 10 students in grade VIII SMP. Data collection techniques applied in this study were questionnaires, while the research instruments used included validation sheets, media use questionnaires, and student response questionnaires. The research data were analyzed by descriptive qualitative. The results of this study indicate that mathematics comics are declared valid with a validity score of 4 by media experts and 3.9 by material experts from a maximum score of 5 so that they are categorized valid, mathematical comics are declared practical with the results of a practicality percentage analysis of 76.28% and mathematical comics are declared effective with the result of the analysis of the effectiveness percentage is 79.4%, so it is categorized as effective. Based on these results, this comic media has good quality so that it can be used as an alternative media used by teachers in the teaching and learning process in an effort to improve the quality of education and create a pleasant atmosphere for students.Keywords: learning media, mathematical comics, circles

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Metagenomic and Metatranscriptomic Responses of Chemical Dispersant Application during a Marine Dilbit Spill

Applied and Environmental Microbiology ◽

10.1128/aem.02151-21 ◽

2022 ◽

Author(s):

Yiqi Cao ◽

Baiyu Zhang ◽

Charles W. Greer ◽

Kenneth Lee ◽

Qinhong Cai ◽

...

Keyword(s):

Microbial Community ◽

Late Stage ◽

Large Scale ◽

Community Dynamics ◽

Early Stage ◽

Small Scale ◽

Rrna Gene ◽

Shotgun Metagenomics ◽

Microcosm Studies ◽

Over Time

The global increase in marine transportation of dilbit (diluted bitumen) can increase the risk of spills, and the application of chemical dispersants remains a common response practice in spill events. To reliably evaluate dispersant effects on dilbit biodegradation over time, we set large-scale (1500 mL) microcosms without nutrients addition using low dilbit concentration (30 ppm). Shotgun metagenomics and metatranscriptomics were deployed to investigate microbial community responses to naturally and chemically dispersed dilbit. We found that the large-scale microcosms could produce more reproducible community trajectories than small-scale (250 mL) ones based on the 16S rRNA gene amplicon sequencing. In the early-stage large-scale microcosms, multiple genera were involved into the biodegradation of dilbit, while dispersant addition enriched primarily Alteromonas and competed for the utilization of dilbit, causing depressed degradation of aromatics. The metatranscriptomic based Metagenome Assembled Genomes (MAG) further elucidated early-stage microbial antioxidation mechanism, which showed dispersant addition triggered the increased expression of the antioxidation process genes of Alteromonas species. Differently, in the late stage, the microbial communities showed high diversity and richness and similar compositions and metabolic functions regardless of dispersant addition, indicating the biotransformation of remaining compounds can occur within the post-oil communities. These findings can guide future microcosm studies and the application of chemical dispersants for responding to a marine dilbit spill. Importance In this study, we employed microcosms to study the effects of marine dilbit spill and dispersant application on microbial community dynamics over time. We evaluated the impacts of microcosm scale and found that increasing the scale is beneficial for reducing community stochasticity, especially in the late stage of biodegradation. We observed that dispersant application suppressed aromatics biodegradation in the early stage (6 days) whereas exerting insignificant effects in the late stage (50 days), from both substances removal and metagenomic/metatranscriptomic perspectives. We further found that Alteromonas species are vital for the early-stage chemically dispersed oil biodegradation, and clarified their degradation and antioxidation mechanisms. The findings would help to better understand microcosm studies and microbial roles for biodegrading dilbit and chemically dispersed dilbit, and suggest that dispersant evaluation in large-scale systems and even through field trails would be more realistic after marine oil spill response.

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Progress towards small-scale field trials of coastal enhanced weathering of olivine

10.5194/egusphere-egu21-14112 ◽

2021 ◽

Author(s):

Stephen Romaniello ◽

Shanee Stopnitzky ◽

Tom Green ◽

Francesc Montserrat ◽

Eric Matzner ◽

...

Keyword(s):

Real World ◽

Field Experiments ◽

Ecological Impact ◽

Field Trials ◽

Research Strategy ◽

Unintended Consequences ◽

Ecological Impacts ◽

Small Scale ◽

Climate Mitigation ◽

Stage Of Development

Slow progress towards achieving global greenhouse gas emissions targets significantly increases the likelihood that future climate efforts may require not only emissions cuts but also direct climate mitigation via negative emissions technologies (IPCC AR5). Currently, such technologies exist at only a nascent stage of development, with significant uncertainties regarding their feasibility, cost, and potential unintended consequences and/or co-benefits.Coastal enhanced weathering of olivine (CEWO) has been suggested as one potential pathway for achieving net negative CO2 emissions at scale. CEWO involves the mining of olivine-rich ultramafic rocks (such as dunite) for incorporation during beach augmentation and restoration work. While grinding this rock into increasingly fine particle sizes is essential for increasing its surface area and reactivity, this step is also costly and energetically expensive. CEWO attempts to minimize this cost and energy penalty by relying on wave and tidal action to provide ongoing physical weathering of olivine grains once distributed on beaches. Laboratory experiments and carbon emissions assessments of CEWO suggest that these approaches may be technically feasible and carbon negative, but significant uncertainties remain regarding the real-world kinetics of coastal olivine dissolution. Furthermore, concerns about the fate and ecological impact of nickel (Ni) and chromium (Cr)&#8212;potentially toxic trace metals found in olivine&#8212;require careful evaluation.In 2019, Project Vesta was established as a nonprofit, philanthropically funded effort to evaluate the technical feasibility and ecological impacts of CEWO through a dedicated research program ultimately culminating in small-scale, real-world field trials of CEWO. This presentation will provide an overview and discussion of our overall research strategy, share insights from interim modeling and mesocosm experiments designed to ensure the practicality and safety of future field experiments, and explain our approach for ensuring transparent, responsible, and ethical research oversight and governance.

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