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Journal of Nematology 2021Fumigant use in perennial crops can be reduced through prolonging the life of existing orchards. The longer an orchard remains healthy and productive, the less often it...
Fumigant use in perennial crops can be reduced through prolonging the life of existing orchards. The longer an orchard remains healthy and productive, the less often it will be terminated, fumigated, and replanted. Two trials were conducted to determine the effectiveness of DiTera, a toxin produced by the fungus ( and Nema-Q, an extract of the soap bark tree () for management of root-lesion () and ring ( nematodes on walnuts. In the first trial, spring and fall treatments of DiTera were applied each year for four years to variety 'Chandler' scion on seedling 'Paradox' rootstock, and to own-rooted 'Chandler' trees. On 'Paradox' rootstock, both DiTera and Nema-Q increased walnut yields ( ≤ 0.05) and produced more vigorous trees ( ≤ 0.05) without significant reductions in nematode populations ( ≤ 0.05). A second trial was conducted with three rates of DiTera and four rates of Nema-Q, combinations of the two products, and an untreated control on 'Chandler' scion on 'Paradox' rootstock. The highest rate of Nema-Q ( ≤ 0.05), and a combination treatment of DiTera plus Nema-Q ( ≤ 0.05) increased trunk circumference. Several treatments showed reductions in root-lesion and ring nematodes ( ≤ 0.05). Bionematicides can improve yield, growth, and vigor in walnut orchards infested with plant-parasitic nematodes.
PubMed: 33903856
DOI: 10.21307/jofnem-2021-044 -
Journal of Nematology Jan 1980Dispersion, dissipation, and efficacy of gas and gel formulations of methyl bromidechloropicrin (202, 269, 336, and 403 kg/ha) on nematodes and weeds on tomato were...
Dispersion, dissipation, and efficacy of gas and gel formulations of methyl bromidechloropicrin (202, 269, 336, and 403 kg/ha) on nematodes and weeds on tomato were studied in field plots. Concentrations of methyl bromide and chloropicrin 4 hr after soil treatment were greater at a depth of 15 cm than at 30, 45, or 60 cm. The concentrations of both chemicals decreased with lower doses, greater depths, and longer times after application. The gel formulation was more persistent than the gas formulation at both 336 and 403 kg/ha at depths of 30 and 45 cm, especially 24 and 36 hr after chemical application. Plant growth and yield were improved when nematodes and weeds were controlled.
PubMed: 19300668
DOI: No ID Found -
Environmental Monitoring and Assessment Aug 2021
PubMed: 34387752
DOI: 10.1007/s10661-021-09246-0 -
Journal of Nematology Dec 1996Methyl bromide is used extensively on a global basis as a pesticide against nematodes, weeds, insects, fungi, bacteria, and rodents. As a soil fumigant, it is used in...
Methyl bromide is used extensively on a global basis as a pesticide against nematodes, weeds, insects, fungi, bacteria, and rodents. As a soil fumigant, it is used in significant quantities in the production of strawberry and tomato, as well as other agriculture commodities. Grain, fresh fruit, forestry products, and other materials are fumigated with methyl bromide to control pest infestations during transport and storage. Structures also are treated with this chemical to control wood-destroying insects and rodents. However, methyl bromide has been identified as a significant ozone-depleting substance, resulting in regulatory actions being taken by the U.S. Environmental Protection Agency and the United Nations Environment Program (Montreal Protocol). The science linking methyl bromide to ozone depletion is strong and was reinforced by the 1994 UNEP Montreal Protocol Science Assessment on Ozone Depletion, which states, "Methyl bromide continues to be viewed as a significant ozone-depleting compound." Identifying efficacious and viable alternatives in the near term is critical.
PubMed: 19277178
DOI: No ID Found -
MBio Aug 2022This study examined the viability and diversity of fungi harbored in imported wooden handicraft products sold in six retail stores in Florida, United States. Despite...
This study examined the viability and diversity of fungi harbored in imported wooden handicraft products sold in six retail stores in Florida, United States. Despite being subjected to trade regulations that require various sterilization/fumigation protocols, our study demonstrates high survival and diversity of fungi in wood products originating from at least seven countries on three continents. Among these fungi were nonendemic plant and human pathogens, as well as mycotoxin producers. Several products that are sold for use in food preparation and consumption harbored a novel (to North America) plant and human pathogen, . In addition, a high number of species isolated were thermophilic and included halophilic species, suggesting adaptability and selection through current wood treatment protocols that utilize heat and/or fumigation with methyl-bromide. This research suggests that current federal guidelines for imports of wooden goods are not sufficient to avoid the transit of potential live pathogens and demonstrates the need to increase safeguards at both points of origin and entry for biosecurity against introduction from invasive fungal species in wood products. Future import regulations should consider living fungi, their tolerance to extreme conditions, and their potential survival in solid substrates. Mitigation efforts may require additional steps such as more stringent fumigation and/or sterilization strategies and limiting use of wood that has not been processed to remove bark and decay. This study, the first of its kind, demonstrates the risk of importation of nonendemic foreign fungi on wooden handicrafts into the United States despite the application of sanitation protocols. Previous risk assessments of imported wood products have focused on potential for introduction of invasive arthropods (and their fungal symbionts) or have focused on other classes of wood products (timber, wooden furniture, garden products, etc.). Little to no attention has been paid to wooden handicrafts and the fungal pathogens (of plants and humans) they may carry. Due to the large size and diversity of this market, the risk for introduction of potentially dangerous pathogens is significant as illustrated by the results of this study.
Topics: Florida; Fungi; Humans; North America; United States; Wood
PubMed: 35766379
DOI: 10.1128/mbio.01075-22 -
The Journal of Toxicological Sciences Nov 1980Cytotoxicity of methyl bromide on cultured mammalian cells was examined. Acute toxic action was induced by methyl bromide itself and its cytotoxicity was reduced in the... (Comparative Study)
Comparative Study
Cytotoxicity of methyl bromide on cultured mammalian cells was examined. Acute toxic action was induced by methyl bromide itself and its cytotoxicity was reduced in the presence of glutathione. Its hydrolysis products or its reaction products with organic compounds in the medium was extremely low in toxicity. Although methyl bromide is known to be a methylating agent, morphological changes induced on HeLa cells were different from the changes characteristic of chemotherapeutic alkylating agents. Lethal concentration of methyl bromide on HeLa cells and primary cultured muscle, kidney and brain cells was similar (10 microgram/ml). In a detailed survey, however, there was a slight difference in the susceptibility among the cells from primary culture of brain.
Topics: Animals; Brain; Cell Survival; Cells, Cultured; Glutathione; HeLa Cells; Humans; Hydrocarbons, Brominated; Kidney; Muscles; Rats
PubMed: 7218378
DOI: 10.2131/jts.5.321 -
Frontiers in Public Health 2023Methyl bromide (MB) is worldwide the only effective fumigant heavily used for quarantine pre-shipment treatment and has a critical use exemption for soil fumigations due...
Methyl bromide (MB) is worldwide the only effective fumigant heavily used for quarantine pre-shipment treatment and has a critical use exemption for soil fumigations due to its excellent permeability and insecticidal effect. However, MB should be replaced as it is an an ozone-depleting substance and also highly toxic to humans. Recently, MB has been shown to be hazardous even for asymptomatic workers, affecting their central and autonomic nervous systems. However, the effects of MB exposure on vascular health have not been explored. This study aimed to determine whether MB affects the arterial system of asymptomatic workers. We measured the second derivative of the photoplethysmogram (SDPTG) indices, which are indicators of vascular load and aging, and urinary bromide ion (Br) concentrations in 44 fumigators (study group) and 20 inspectors (control group) before and after fumigation. In fumigators, the mean values of post-work SDPTG indices (b/a, c/a, d/a, e/a, and SDPTG aging index) and Br levels were significantly changed compared to their pre-work values ( < 0.05), indicating a negative effect on their cardiovascular health. In contrast, SDPTG indices and Br levels in inspectors did not show any differences before and after work. All SDPTG indices except c/a showed significant correlations with Br levels in all individuals ( < 0.05). In conclusion, the Br levels and SDPTG indices of fumigators varied after MB work, and they experienced negative effects on their health despite being asymptomatic.
Topics: Humans; Photoplethysmography; Aging; Hydrocarbons, Brominated; Insecticides
PubMed: 37818301
DOI: 10.3389/fpubh.2023.1224143 -
Plant Disease Oct 2000Field trials were conducted in 1996 and 1997 to determine the effect of plant growth-promoting rhizobacteria (PGPR) strains, which previously were found to induce...
Field trials were conducted in 1996 and 1997 to determine the effect of plant growth-promoting rhizobacteria (PGPR) strains, which previously were found to induce systemic resistance in cucumber, on cucumber plant growth and on naturally occurring cucumber diseases with and without methyl bromide fumigation. Seven PGPR seed treatments included single-strain treatments and mixtures of Bacillus pumilus strain INR7, Curtobacterium flaccumfaciens strain ME1, and Bacillus subtilis strain GB03. In both years, in the absence of methyl bromide, all seven PGPR treatments significantly promoted plant growth, compared to the non-treated control, while with methyl bromide fumigation, only 3 and 1 of the same PGPR treatments promoted growth significantly in 1996 and 1997, respectively. In 1996, main runner length of plants in all seven PGPR treatments without fumigation was statistically equivalent to the main runner length of the nontreated control with methyl bromide fumigation. Naturally occurring foliar diseases were angular leaf spot, caused by Pseudomonas syringae pv. lachrymans in 1996, and a mixed infestation of angular leaf spot and anthracnose, caused by Colletotrichum orbiculare in 1997. In both years, all PGPR treatments significantly reduced severity of foliar disease, compared to the nontreated control, with and without methyl bromide. Mixtures of PGPR strains showed a higher level of disease protection in both years with and without methyl bromide. The results indicate that attempts to develop PGPR-mediated induced systemic resistance into components of vegetable integrated pest management should not be negatively impacted by the planned withdraw of MeBr from standard vegetable production and that PGPR may help compensate for reduced plant growth often seen without methyl bromide fumigation.
PubMed: 30831895
DOI: 10.1094/PDIS.2000.84.10.1073 -
Journal of Food Protection Sep 2017The purpose of this review is to delineate means of decontaminating soil. This information might be used to mitigate soil-associated risks of foodborne pathogens. The... (Review)
Review
The purpose of this review is to delineate means of decontaminating soil. This information might be used to mitigate soil-associated risks of foodborne pathogens. The majority of the research in the published literature involves inactivation of plant pathogens in soil, i.e., those pathogens harmful to fruit and vegetable production and ornamental plants. Very little has been published regarding the inactivation of foodborne human pathogens in crop soil. Nevertheless, because decontamination techniques for plant pathogens might also be useful methods for eliminating foodborne pathogens, this review also includes inactivation of plant pathogens, with appropriate discussion and comparisons, in the hopes that these methods may one day be validated against foodborne pathogens. Some of the major soil decontamination methods that have been investigated and are covered include chemical decontamination (chemigation), solarization, steaming, biofumigation, bacterial competitive exclusion, torch flaming, microwave treatment, and amendment with biochar. Other innovative means of inactivating foodborne pathogens in soils may be discovered and explored in the future, provided that these techniques are economically feasible in terms of chemicals, equipment, and labor. Food microbiology and food safety researchers should reach out to soil scientists and plant pathologists to create links where they do not currently exist and strengthen relationships where they do exist to take advantage of multidisciplinary skills. In time, agricultural output and the demand for fresh produce will increase. With advances in the sensitivity of pathogen testing and epidemiological tracebacks, the need to mitigate preharvest bacterial contamination of fresh produce will become paramount. Hence, soil decontamination technologies may become more economically feasible and practical in light of increasing the microbial safety of fresh produce.
Topics: Decontamination; Food Contamination; Food Microbiology; Food Safety; Humans; Soil; Soil Microbiology; Vegetables
PubMed: 28782997
DOI: 10.4315/0362-028X.JFP-17-040 -
American Journal of Public Health Dec 1998This study assessed the health effects associated with occupational exposure to methyl bromide and sulfuryl fluoride among structural fumigation workers.
OBJECTIVES
This study assessed the health effects associated with occupational exposure to methyl bromide and sulfuryl fluoride among structural fumigation workers.
METHODS
A cross-sectional study of 123 structural fumigation workers and 120 referents in south Florida was conducted. Nerve conduction, vibration, neurobehavioral, visual, olfactory, and renal function testing was included.
RESULTS
The median lifetime duration of methyl bromide and sulfuryl fluoride exposure among workers was 1.20 years and 2.85 years, respectively. Sulfuryl fluoride exposure over the year preceding examination was associated with significantly reduced performance on the Pattern Memory Test and on olfactory testing. In addition, fumigation workers had significantly reduced performance on the Santa Ana Dexterity Test of the dominant hand and a nonsignificantly higher prevalence of carpal tunnel syndrome than did the referents.
CONCLUSIONS
Occupational sulfuryl fluoride exposures may be associated with subclinical effects on the central nervous system, including effects on olfactory and some cognitive functions. However, no widespread pattern of cognitive deficits was observed. The peripheral nerve effects were likely caused by ergonomic stresses experienced by the fumigation workers.
Topics: Adult; Aged; Case-Control Studies; Cross-Sectional Studies; Florida; Fumigation; Humans; Hydrocarbons, Brominated; Insecticides; Kidney Diseases; Linear Models; Lung Diseases; Male; Middle Aged; Nervous System Diseases; Neuropsychological Tests; Occupational Diseases; Occupational Exposure; Sulfinic Acids
PubMed: 9842373
DOI: 10.2105/ajph.88.12.1774