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1.
J Pediatr ; : 114168, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38944190

RESUMO

To evaluate the utilization of the American Academy of Pediatrics' (AP) cardiovascular screening questions within preparticipation physical evaluation forms from the 50 state high school athletic associations. We found that fewer than half of state forms incorporated all 10 AAP questions; moreover, a subset failed to adhere to criteria recommended by either the AAP or American Heart Association.

2.
Plant Dis ; : PDIS12232726RE, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38499976

RESUMO

Meloidogyne enterolobii is an emerging global threat and is damaging to sweetpotato (Ipomoea batatas) production in the southeast United States. Nematicide application is one of the few management strategies currently available against this nematode, and field testing is urgently needed. The objective of this study was to assess common nematicides for management of M. enterolobii and nontarget effects on free-living nematodes in sweetpotato field production. Treatments were (i) untreated control, (ii) fumigation using 1,3-dichloropropene, or at-transplant drench of fluorinated nematicides (iii) fluazaindolizine, (iv) fluopyram, or (v, vi) fluensulfone at 2 or 4 kg a.i./ha. In 2022, a field trial was conducted under severe M. enterolobii pressure and was repeated in 2023 in the same location without treatment rerandomization. Fumigation using 1,3-dichloropropene (1,3-D) was the only consistently effective nematicide at improving marketable yield relative to control and also consistently reduced most storage root galling measurements and midseason Meloidogyne soil abundances. Fluensulfone at 4 kg a.i./ha consistently improved total yield but not marketable yield, whereas fluensulfone at 2 kg a.i./ha, fluazaindolizine, and fluopyram did not improve yield. Each fluorinated nematicide treatment reduced at least one nematode symptom or nematode soil abundances relative to control, but none provided consistent benefits across years. Even with 1,3-D fumigation, yield was poor, and none of the nematicide treatments provided a significant return on investment relative to forgoing nematicide application. There were minimal effects on free-living nematodes. In summary, 1,3-D is an effective nematicide for M. enterolobii management, but additional management will be needed under severe M. enterolobii pressure.

3.
ACS Appl Mater Interfaces ; 16(13): 16754-16766, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38517314

RESUMO

We report a highly controlled technique for the synthesis of polymer films atop a substrate by combining spin coating with ring-opening metathesis polymerization (ROMP), herein termed spin coating ROMP (scROMP). The scROMP approach combines polymer synthesis and deposition into one process, fabricating films of up to 36 cm2 in under 3 min with orders-of-magnitude reduction in solvent usage. This method can convert numerous norbornene-type molecules into homopolymers and random copolymers as uniform films on both porous and nonporous substrates. Film thickness can be varied from a few hundred nanometers to a few tens of micrometers based on spin speed and monomer concentration. The resulting polymers possess high MW (>100 kDa) and low polydispersity (PDI) (<1.2) values that are similar to ROMP polymers made in solution. We also devise a model to investigate the balance between convective monomer spin-off and polymer growth from the surface, which allows the determination of critical kinetic parameters for scROMP. Finally, translation of scROMP to porous supports enables the synthesis of thin film composite membranes that demonstrate the ability to dehydrate ethanol by pervaporation.

5.
J Nematol ; 55(1): 20230041, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37868787

RESUMO

Rotylenchulus reniformis (reniform nematode, RN) is among the most important nematodes affecting cotton. Cultural practices, such as rotation and soil amendment, are established methods for managing RN. Management may be enhanced if crop residue has biofumigant properties against RN. The objective was to evaluate the efficacy of winter crop amendments for managing RN in the greenhouse. Reniform nematode-infested soil was amended with dry or fresh organic matter (OM, 2% w/w) from winter crops - canola, carinata, hairy vetch, oat, or no crop. Cotton was subsequently grown in this soil. Independent of the crop, dry OM amendments were more effective than no amendment at managing RN, while fresh OM amendments were not. Soil and root RN abundances and reproduction factors were generally lower in Trials 1 and 3 for dry OM than fresh OM amendments or control without OM. In Trial 2, none of the OM treatments reduced RN parameters compared with no OM control. In general, when compared to plants without RN or OM, RN did not produce significant changes in growth parameters but did affect physiology (Soil Plant Analysis Development, or SPAD, values). In conclusion, dry OM amendments can help manage RN, crop growth does not always relate to RN abundances, and SPAD values could help indicate RN presence.

6.
BMJ Open Ophthalmol ; 8(Suppl 3): A6-A7, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37797991

RESUMO

Involving children and young people (CYP) in service and research design improves quality and accessibility. Running events in schools to invite CYP to volunteer and explore careers in the NHS may contribute to uptake of training posts and developing the NHS workforce.Here we evaluate two activities with CYP, our Young Person's Advisory Group for research (eye-YPAG) and our workshop for secondary schools, 'visually'.We evaluated eye-YPAG in focus groups and online surveys with group members, parents/carers, researchers, facilitators and funders. We conducted thematic analysis and descriptive statistics. To evaluate 'visually', we monitored the numbers of workshops and young people applying for volunteering roles. We asked those who started working with us about their experience.eye-YPAG members valued social and creative aspects as well as learning about research and developing skills and confidence. Researchers reported that CYP gave novel suggestions, modifying research plans, and that their different perspective was helpful in making research more relevant for children and families.Over 6 months, we held 15 'visually' workshops in secondary schools. Ninety students applied for volunteering roles, and 20 have completed the Human Resources onboarding process. Young volunteers report that this work has increased their confidence and that they have gained insights into how a hospital works. One is considering training to become an orthoptist.Both eye-YPAG and 'visually' are available to all eye researchers and units in the UK and can facilitate outreach activities.


Assuntos
Pais , Estudantes , Criança , Humanos , Adolescente , Aprendizagem , Instituições Acadêmicas , Recursos Humanos
7.
J Nematol ; 55(1): 20230035, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37712053

RESUMO

Rotylenchulus reniformis (reniform nematode, RN) is an important pathogen in cotton production. Cultural practices such as crop rotation and biofumigation-management of soil pathogens by biocidal compounds from crop residues-may help manage RN. The objective of this study was to evaluate the efficacy of winter crops for RN management through combinations of rotation and crop residue incorporation in a cotton greenhouse experiment. A total of 10 treatments were evaluated in soil inoculated with RN: three winter crops (carinata, oat, or hairy vetch) grown in rotation with no shoot organic matter (OM) incorporated (1-3), fresh shoot OM incorporated (4-6), or dry shoot OM incorporated (7-9), and a fallow control (10). Roots were re-incorporated in all treatments except fallow. Subsequently, cotton was grown. Oat and fallow were better rotation crops to lower soil RN abundances at winter crop termination than hairy vetch and carinata. After the OM incorporation treatments and cotton growth, oat was generally more effective at managing RN in cotton than carinata or hairy vetch. Within each crop, incorporation treatment generally did not affect RN management. Cotton growth was not consistently affected by the treatments.

8.
Nanoscale Adv ; 5(19): 5301-5308, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37767044

RESUMO

The combination of conducting polymers with electro- and photoactive proteins into thin films holds promise for advanced energy conversion materials and devices. The emerging field of protein electronics requires conductive soft materials in a composite with electrically insulating proteins. The electropolymerization of pyrrole through voids in a drop-casted photosystem I (PSI) multilayer film enables the straightforward fabrication of photoactive and conductive biohybrid films. The rate of polypyrrole (PPy) growth is reduced by the presence of the PSI film but is insensitive to its thickness, suggesting that rapid diffusion of pyrrole through the voids within the PSI film enables initiation at vacant areas on the gold surface. The base thickness of the composite tends to increase with time, as PPy chains propagate through and beyond the PSI film, coalescing to exhibit a tubule-like morphology as observed by scanning electron microscopy. Increasing amounts of PPy greatly increase the capacitance of the composite films in a manner almost identical to that of pure PPy films grown from unmodified gold, consistent with a high polymer/aqueous interfacial area and a conductive composite film. While PPy is not photoactive here, all composite films, including those with large amounts of PPy, exhibit photocurrents when irradiated by white light in the presence of redox mediator species. Optimization of the Py electropolymerization time is necessary, as increasing amounts of PPy lead to decreased photocurrent density due to a combination of light absorbance by the polymer and reduced accessibility of redox species to active PSI sites.

9.
J Nematol ; 55(1): 20230028, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37426724

RESUMO

Belonolaimus longicaudatus (sting nematode) is an important pest in Florida potato production and is managed primarily by fumigation using 1,3-dichloropropene (1,3-D). Other effective nematicides are needed for more flexibility in managing this pest. The objective of this study was to evaluate fluensulfone, metam potassium, and mixtures of the two products, relative to 1,3-D and untreated control, for efficacy at managing sting nematode, and for non-target effects on free-living nematodes in potato. To test this objective, a small-plot field experiment was conducted in northeast Florida in 2020 and repeated in 2021. Metam potassium fumigation (390 kg a.i./treated ha)-with or without fluensulfone-managed sting nematode soil abundances but was phytotoxic to potato. Strategies that mitigate metam potassium phytotoxicity, such as reduced application rates, are needed before efficacy of metam potassium in this system can be determined. As a preplant soil spray, fluensulfone alone (403 g a.i./treated ha) did not manage sting nematode abundances and had an inconsistent effect on yield. Fumigation with 1,3-D (88.3 kg a.i./treated ha) was the only treatment that consistently managed sting nematode and increased potato yield. Nematicides did not consistently affect free-living nematodes.

10.
J Cell Sci ; 136(11)2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37305999

RESUMO

The budding yeast Saccharomyces cerevisiae has a closed mitosis in which the mitotic spindle and the cytoplasmic microtubules (MTs), both of which generate forces to faithfully segregate chromosomes, remain separated by the nuclear envelope throughout the cell cycle. Kar3, the yeast kinesin-14, has distinct functions on MTs in each compartment. Here, we show that two proteins, Cik1 and Vik1, which form heterodimers with Kar3, regulate its localization and function within the cell, and along MTs in a cell cycle-dependent manner. Using a yeast MT dynamics reconstitution assay in lysates from cell cycle-synchronized cells, we found that Kar3-Vik1 induces MT catastrophes in S phase and metaphase, and limits MT polymerization in G1 and anaphase. In contrast, Kar3-Cik1 promotes catastrophes and pauses in G1, while increasing catastrophes in metaphase and anaphase. Adapting this assay to track MT motor protein motility, we observed that Cik1 is necessary for Kar3 to track MT plus-ends in S phase and metaphase but, surprisingly, not during anaphase. These experiments demonstrate how the binding partners of Kar3 modulate its diverse functions both spatially and temporally.


Assuntos
Cinesinas , Saccharomyces cerevisiae , Cinesinas/genética , Ciclo Celular , Anáfase , Metáfase
11.
Pediatrics ; 151(1)2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36519230

RESUMO

BACKGROUND AND OBJECTIVES: Annual preparticipation physical evaluation (PPE) is used in the United States to screen adolescents for potential causes of sudden cardiac death. The American Heart Association recommends 14 screening elements of history and physical examination. This study sought to define the utilization of these screening elements by each of the 50 states before high school athletics. METHODS: PPE forms were obtained from the public website of the high school athletics governing body in every state. Form content was analyzed to identify which of the 14 screening elements were explicitly fulfilled. Additional PPE forms provided by private/parochial schools, other professional societies, or independent groups were excluded from this study. RESULTS: A total of 48 states (96%) had PPE forms posted online. The remaining 2 states (4%) deferred the specific method of PPE documentation to individual school districts and provided no standardized form. Of the 48 states providing PPE forms, 13 (27%) included all 14 American Heart Association screening elements. The median criteria included by each state was 11 (range 3-14). The 3 criteria most commonly absent were (1) the examination of femoral pulses to exclude coarctation (58%), (2) a family history of specific inherited cardiac disease (31%), and (3) personal history of hypertension (27%). CONCLUSIONS: Annual preparticipation forms are important screening tools. Only a minority of states include all 14 cardiac screening elements recommended by the American Heart Association.


Assuntos
Cardiopatias , Esportes , Adolescente , Humanos , Estados Unidos , Programas de Rastreamento/métodos , Atletas , Cardiopatias/diagnóstico , Morte Súbita Cardíaca/prevenção & controle , Exame Físico
12.
J Nematol ; 54(1): 20220046, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36457366

RESUMO

Plant-parasitic and free-living nematodes - bacterivores, fungivores, omnivores, predators - comprise the nematode community. Nematicide application and crop rotation are important tools to manage plant-parasitic nematodes, but effects on free-living nematodes and nematode ecological indices need further study. The nematicide fluopyram was recently introduced in cotton (Gossypium hirsutum) production and its effects on the nematode community need assessment. This research was conducted in 2017 and 2018 at a long-term field site in Quincy, FL where perennial grass/sod-based (bahiagrass, Paspalum notatum) and conventional cotton rotations were established in 2000. The objective of this research was to evaluate the effects of fluopyram nematicide, crop rotation phase, and irrigation on free-living nematodes and nematode ecological indices based on three soil sampling dates each season. We did not observe consistent effects of crop rotation phase on free-living nematodes or nematode ecological indices. Only omnivores were consistently negatively impacted by fluopyram. Nematode ecological indices reflected this negative effect by exhibiting a degraded/ stressed environmental condition relative to untreated plots. Free-living nematodes were not negatively impacted by nematicide when sod-based rotation was used.

13.
J Nematol ; 54(1): 20220019, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35860512

RESUMO

Sting nematode is acutely damaging to a wide range of crops and is relatively common in sandy soils in the southeastern United States. Sweetpotato is an important crop in this region, and its production may be expanding to localities where sting nematode is an important pest. Despite this, the relationship between sweetpotato and sting nematode is not well-defined. Therefore, the objectives of this study were to assess (1) the relative host status of sweetpotato for sting nematode and (2) damage potential of sting nematode on sweetpotato in repeated greenhouse experiments. A known sting nematode host (field corn), a known poor host (sunn hemp), and sweetpotato cultivars susceptible ('Beauregard') and resistant ('Covington') to southern root-knot nematode were challenged with sting nematode. In both trials, field corn supported greater final soil sting nematode abundances than sunn hemp or either sweetpotato cultivar. Based on the average reproductive factor, field corn was confirmed as a susceptible host, whereas sunn hemp and sweetpotato were poor hosts. Sting nematode did not impair the growth of any crop, suggesting greenhouse conditions were not conducive to damage since field corn sustains damage in field conditions. These results suggest that sunn hemp and sweetpotato could be useful rotation crops for managing sting nematode, but future work is needed to assess sting nematode pathogenicity on these crops under field conditions.

14.
J Trauma Acute Care Surg ; 93(5): 604-612, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35444156

RESUMO

BACKGROUND: Posttraumatic venous thromboembolism (VTE) remains prevalent in severely injured patients despite chemoprophylaxis. Importantly, although platelets are central to thrombosis, they are not routinely targeted in prevention of posttraumatic VTE. Furthermore, platelets from injured patients show ex vivo evidence of increased activation yet impaired aggregation, consistent with functional exhaustion. However, the relationship of this platelet functional phenotype with development of posttraumatic VTE is unknown. We hypothesized that, following injury, impaired ex vivo platelet aggregation (PA) is associated with the development of posttraumatic VTE. METHODS: We performed a secondary analysis of 133 severely injured patients from a prospective observational study investigating coagulation and inflammation (2011-2019). Platelet aggregation in response to stimulation with adenosine diphosphate (ADP), collagen, and thrombin was measured at presentation (preresuscitation) and 24 hours (postresuscitation). Viscoelastic clot strength and lysis were measured in parallel by thromboelastography. Multivariable regression examined relationships between PA at presentation, 24 hours, and the change (δ) in PA between presentation and 24 hours with development of VTE. RESULTS: The 133 patients were severely injured (median Injury Severity Score, 25), and 14% developed VTE (all >48 hours after admission). At presentation, platelet count and PA were not significantly different between those with and without incident VTE. However, at 24 hours, those who subsequently developed VTE had significantly lower platelet counts (126 × 10 9 /L vs. 164 × 10 9 /L, p = 0.01) and lower PA in response to ADP ( p < 0.05), collagen ( p < 0.05), and thrombin ( p = 0.06). Importantly, the magnitude of decrease in PA (δ) from presentation to 24 hours was independently associated with development of VTE (adjusted odds ratios per 10 aggregation unit decrease: δ-ADP, 1.31 [ p = 0.03]; δ-collagen, 1.36 [ p = 0.01]; δ-thrombin, 1.41 [ p < 0.01]). CONCLUSION: Severely injured patients with decreasing ex vivo measures of PA despite resuscitation have an increased risk of developing VTE. This may have implications for predicting development of VTE and for studying platelet targeted chemoprophylaxis regimens. LEVEL OF EVIDENCE: Prognostic/Epidemiological; Level III.


Assuntos
Tromboembolia Venosa , Humanos , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle , Agregação Plaquetária , Trombina , Testes de Função Plaquetária , Difosfato de Adenosina
15.
Am J Bot ; 109(4): 564-579, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35274309

RESUMO

PREMISE: Trees in wet forests often have features that prevent water films from covering stomata and inhibiting gas exchange, while many trees in drier environments use foliar water uptake to reduce water stress. In forests with both wet and dry seasons, evergreen trees would benefit from producing leaves capable of balancing rainy-season photosynthesis with summertime water absorption. METHODS: Using samples collected from across the vertical gradient in tall redwood (Sequoia sempervirens) crowns, we estimated tree-level foliar water uptake and employed physics-based causative modeling to identify key functional traits that determine uptake potential by setting hydraulic resistance. RESULTS: We showed that Sequoia has two functionally distinct shoot morphotypes. While most shoots specialize in photosynthesis, the axial shoot type is capable of much greater foliar water uptake, and its within-crown distribution varies with latitude. A suite of leaf surface traits cause hydraulic resistance, leading to variation in uptake capacity among samples. CONCLUSIONS: Shoot dimorphism gives tall Sequoia trees the capacity to absorb up to 48 kg H2 O h-1 during the first hour of leaf wetting, ameliorating water stress while presumably maintaining high photosynthetic capacity year round. Geographic variation in shoot dimorphism suggests that plasticity in shoot-type distribution and leaf surface traits helps Sequoia maintain a dominate presence in both wet and dry forests.


Assuntos
Sequoia , Desidratação , Fotossíntese , Folhas de Planta , Caracteres Sexuais , Árvores
16.
G3 (Bethesda) ; 12(1)2022 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-35100403

RESUMO

Sequencing, assembly, and annotation of the 26.5 Gbp hexaploid genome of coast redwood (Sequoia sempervirens) was completed leading toward discovery of genes related to climate adaptation and investigation of the origin of the hexaploid genome. Deep-coverage short-read Illumina sequencing data from haploid tissue from a single seed were combined with long-read Oxford Nanopore Technologies sequencing data from diploid needle tissue to create an initial assembly, which was then scaffolded using proximity ligation data to produce a highly contiguous final assembly, SESE 2.1, with a scaffold N50 size of 44.9 Mbp. The assembly included several scaffolds that span entire chromosome arms, confirmed by the presence of telomere and centromere sequences on the ends of the scaffolds. The structural annotation produced 118,906 genes with 113 containing introns that exceed 500 Kbp in length and one reaching 2 Mb. Nearly 19 Gbp of the genome represented repetitive content with the vast majority characterized as long terminal repeats, with a 2.9:1 ratio of Copia to Gypsy elements that may aid in gene expression control. Comparison of coast redwood to other conifers revealed species-specific expansions for a plethora of abiotic and biotic stress response genes, including those involved in fungal disease resistance, detoxification, and physical injury/structural remodeling and others supporting flavonoid biosynthesis. Analysis of multiple genes that exist in triplicate in coast redwood but only once in its diploid relative, giant sequoia, supports a previous hypothesis that the hexaploidy is the result of autopolyploidy rather than any hybridizations with separate but closely related conifer species.


Assuntos
Sequoia , Evolução Biológica , Cromossomos , Genoma , Sequenciamento de Nucleotídeos em Larga Escala , Sequoia/genética
17.
Plant Dis ; 106(8): 2228-2238, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34978874

RESUMO

Meta-analysis was used to compare yield protection and nematode suppression provided by two seed-applied and two soil-applied nematicides against Meloidogyne incognita and Rotylenchulus reniformis on cotton across 3 years and several trial locations in the U.S. Cotton Belt. Nematicides consisted of thiodicarb- and fluopyram-treated seed, aldicarb and fluopyram applied in furrow, and combinations of the seed treatments and soil-applied fluopyram. The nematicides had no effect on nematode reproduction or root infection but had a significant impact on seed cotton yield response ([Formula: see text]), with an average increase of 176 and 197 kg/ha relative to the nontreated control in M. incognita and R. reniformis infested fields, respectively. However, because of significant variation in yield protection and nematode suppression by nematicides, five or six moderator variables (cultivar resistance [M. incognita only], nematode infestation level, nematicide treatment, application method, trial location, and growing season) were used depending on nematode species. In M. incognita-infested fields, greater yield protection was observed with nematicides applied in furrow and with seed-applied + in-furrow than with solo seed-applied nematicide applications. Most notable of these in-furrow nematicides were aldicarb and fluopyram (>131 g/ha) with or without a seed-applied nematicide compared with thiodicarb. In R. reniformis-infested fields, moderator variables provided no further explanation of the variation in yield response produced by nematicides. Furthermore, moderator variables provided little explanation of the variation in nematode suppression by nematicides in M. incognita- and R. reniformis-infested fields. The limited explanation by the moderator variables on the field efficacy of nematicides in M. incognita- and R. reniformis-infested fields demonstrates the difficulty of managing these pathogens with nonfumigant nematicides across the U.S. Cotton Belt.


Assuntos
Antinematódeos , Tylenchoidea , Aldicarb/toxicidade , Animais , Antinematódeos/toxicidade , Benzamidas/toxicidade , Gossypium , Piridinas/toxicidade , Sementes , Solo , Tylenchoidea/efeitos dos fármacos , Tylenchoidea/fisiologia , Estados Unidos
18.
MRS Commun ; 11(6): 701-715, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34931153

RESUMO

The oil and gas industry has been tagged as among the largest revenue-generating sectors in the world. High-performance polymers (HPPs), on the other hand, are among the most useful industrial materials, while the utility of 3D printing technologies has evolved and transitioned from rapid prototyping of composite materials to manufacturing of functional parts. In this prospective, we highlight the potential uses and industrial applications of 3D-printed HPP materials in the oil and gas sector, including the challenges and opportunities present.

19.
J Nematol ; 532021.
Artigo em Inglês | MEDLINE | ID: mdl-34671749

RESUMO

Organic and conventional production are common in horticulture crops and each system may exert a different influence on the soil ecosystem, particularly the nematode community. Crop nutrient rate is an important choice in both production systems. The objectives of this study were to assess the impacts of (i) organic and conventional production systems and (ii) nutrient rate in both systems on the nematode community in carrot production. To investigate these objectives, field studies in organic and conventional production - which included fumigation with 1,3-dichloropropene - were conducted in North-Central Florida. In both production systems, nutrient rate treatments were 168, 224, 280, 336, and 392 kg N/ha. Poultry litter was the nitrogen source in organic production whereas synthetic, inorganic fertilizer was used in conventional production. All nematode trophic groups were consistently more abundant in organic than conventional production. The nematode community was more diverse and had greater trophic structure in organic production. Greater rates of organic nutrients increased enrichment opportunists (bacterivores and fungivores), but inconsistently across years. Conventional production had similar results except that only moderate nutrient rates increased fungivore abundances. Extreme enrichment opportunists (Rhabditis spp.) drove bacterivore trends in organic production whereas moderate enrichment opportunists (Cephalobus spp.) drove trends in conventional production. Nutrient rates did not affect omnivore-predators, herbivores, nematode community diversity, or structure in either system. In summary, type of production system, organic or conventional, exerts a strong influence on the nematode community, but nutrient rate has less consistent effects in horticulture production.

20.
J Nematol ; 532021.
Artigo em Inglês | MEDLINE | ID: mdl-34296191

RESUMO

Meloidogyne incognita (southern root-knot nematode, SRKN) is a major pest in tomato (Solanum lycopersicum) production in the Southeastern United States. Management has relied on fumigant and carbamate non-fumigant nematicides. New non-fumigant nematicides, such as fluopyram, are available and field evaluation of new nematicides is needed. The objectives of this research were to assess the efficacy of new (fluopyram) and established (oxamyl) non-fumigant nematicides as well as fumigation (1,3-dichloropropene) for (1) SRKN management, and (2) impacts on total soil abundances of non-target, free-living nematodes in field tests in Florida. Fumigation with 1,3-D consistently managed SRKN and, in two of three trials, increased yield relative to untreated. Oxamyl and fluopyram also had efficacy in managing SRKN, but were inconsistent from year to year. Oxamyl provided better root galling control than fluopyram in one of two trials, but otherwise those nematicides provided similar SRKN management and yield response. Supplementing 1,3-D fumigation with fluopyram did not improve SRKN management or yield relative to fumigation alone. Fumigation consistently reduced free-living nematode abundances relative to untreated. Oxamyl and fluopyram were more inconsistent, but always reduced total free-living nematode abundances when effective against SRKN. In summary, while non-fumigant nematicides provided some management of SRKN, fumigation continued to be the most consistent option. All nematicides had deleterious effects on free-living nematodes.

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