Rapid non-destructive monitoring and quality assessment of the fumigation process of Shanxi aged vinegar based on Vis-NIR hyperspectral imaging combined with multiple chemometric algorithms.

The quality of the grains during the fumigation process can significantly affect the flavour and nutritional value of Shanxi aged vinegar (SAV). Hyperspectral imaging (HSI) was used to monitor the extent of fumigated grains, and it was combined with chemometrics to quantitatively predict three key physicochemical constituents: moisture content (MC), total acid (TA) and amino acid nitrogen (AAN). The noise reduction effects of five spectral preprocessing methods were compared, followed by the screening of optimal wavelengths using competitive adaptive reweighted sampling. Support vector machine classification was employed to establish a model for discriminating fumigated grains, and the best recognition accuracy reached 100%. Furthermore, the results of partial least squares regression slightly outperformed support vector machine regression, with correlation coefficient for prediction (Rp) of 0.9697, 0.9716, and 0.9098 for MC, TA, and AAN, respectively. The study demonstrates that HSI can be employed for rapid non-destructive monitoring and quality assessment of the fumigation process in SAV.

Electrochemical Generation of Hydroxide and Hydrogen Peroxide for Hydrolysis of Sulfuryl Fluoride Fumigant.

The post-harvest fumigant, sulfuryl fluoride (SO2F2), is a >1000-fold more potent greenhouse gas than carbon dioxide and methane. Pilot studies have shown that SO2F2 fumes vented from fumigation chambers can be captured and hydrolyzed by hydroxide (OH-) and hydrogen peroxide (H2O2) at pH ∼ 12 in a scrubber, producing SO42- and F- as waste salts. To reduce the costs and challenges associated with purchasing and mixing these reagents onsite, this study evaluates the electrochemical generation of OH- and H2O2 within spent scrubbing solution, taking advantage of the waste SO42- and F- as free sources of electrolyte. The study used a gas diffusion electrode constructed from carbon paper coated with carbon black as a catalyst selective for the reduction of O2 to H2O2. Under galvanostatic conditions, the study evaluated the effect of electrochemical conditions, including applied cathodic current density and electrolyte strength. Within an electrolyte containing 200 mM SO42- and 400 mM F-, comparable to the waste salts generated by a SO2F2 scrubbing event, the system produced 250 mM H2O2 at pH 12.6 within 4 h with a Faradaic efficiency of 98.8% for O2 reduction to H2O2. In a scrubbing-water sample from lab-scale fumigation, the system generated ∼200 mM H2O2 at pH 13.5 within 4 h with a Faradaic efficiency of 75.6%. A comparison of the costs to purchase NaOH and H2O2 against the electricity costs for electrochemical treatment indicated that the electrochemical approach could be 38-71% lower, depending on the local cost of electricity.

Effect of fumigation height and time on cryopreservation of ram semen.

The cooling rate is a crucial factor in the process of freezing semen, influencing the overall freezing effectiveness. The height and time of fumigation can significantly impact the rate of cooling. Appropriate cooling rates can help minimize the formation of ice crystals in spermatozoa and reduce potential damage to them. Therefore, the aim of this study was to evaluate the effect of different fumigation heights and time for the cryopreservation of Hu ram semen. Experiments I-IV assessed the effect of semen cryopreservation by testing the post-thawed spermatozoa total motility (TM), progressive motility (PM) and kinetic parameters fumigated at distances of 2, 4, 6 and 8 cm for durations of 5, 10, 15 and 20 min, respectively. Based on the results of experiments I to IV, experiment V evaluated the effect of semen cryopreservation by testing the post-thawed spermatozoa TM, PM, kinetic parameters, plasma membrane integrity, acrosome integrity and reactive oxygen species (ROS) level fumigated at distances of 2, 4, 6 and 8 cm for duration of 20 min. The results indicated that fumigation at 2 cm for 20 min significantly (P < 0.05) improved spermatozoa TM, PM, mean angular displacement (MAD), plasma membrane integrity and acrosome integrity compared to other groups. Additionally, it significantly (P < 0.05) reduced spermatozoa ROS level compared to the 6 and 8 cm groups. In conclusion, fumigation for 20 min at a distance of 2 cm from the liquid nitrogen surface is the most suitable cooling method for the cryopreservation of Hu ram semen.

Soil microeukaryotic communities and phosphorus-cycling microorganisms respond to chloropicrin fumigation and azoxystrobin application.

Fumigants and fungicides are effective at controlling soil-borne pathogens but might also adversely affect soil beneficial microbes, such as soil phosphorus (P) solubilizing microbes, further altering nutrient cycling processes. Therefore, this study investigated the effects of the fumigant chloropicrin (CP) and the fungicide azoxystrobin (AZO) on soil microeukaryotes and P-cycling related soil bacteria through a greenhouse experiment. Soil microeukaryotic communities and bacterial communities containing two phosphomonoesterase encoding genes (phoC and phoD) were analysed using high-throughput sequencing methods. Results showed that, when applied at the field recommended application dosage, the fungicide AZO had no significant influence on the community structure of soil microeukaryotes and phoD-containing bacteria. However, in CP-fumigated soils, the soil microeukaryotic community composition changed from fungi-dominated to protist-dominated. CP fumigation significantly decreased the total phoC/phoD gene copy number but increased the relative abundance of some phoC/phoD-containing bacteria (such as Sinorhizobium and Streptomyces), which are significantly positively correlated to available P compositions in soil. The structural equation model (SEM) confirmed that CP fumigation could affect soil available P content directly by altering phoC-/phoD-containing bacteria, or indirectly by affecting phoC/phoD gene abundance and acid/alkaline phosphatases activity in soil. The inconsistent changes in phoC/phoD-containing bacteria, phoC/phoD gene number, and the phosphomonoesterase activities indicated that enzyme secretion may not be the only way for P solubilizing soil microorganisms to regulate P availability after soil fumigation. The outcome of this study can provide theoretical support for the design of soil beneficial microorganism recovery strategies and the regulation of phosphate fertilizer after soil fumigation.

Influence of molecular descriptors of plant volatilomics on fumigant action against the three major stored product beetle pests.

Plant volatilomics such as essential oils (EOs) and volatile phytochemicals (PCs) are known as potential natural sources for the development of biofumigants as an alternative to conventional fumigant pesticides. This present work was aimed to evaluate the fumigant toxic effect of five selected EOs (cinnamon, garlic, lemon, orange, and peppermint) and PCs (citronellol, limonene, linalool, piperitone, and terpineol) against the Callosobruchus maculatus, Sitophilus oryzae, and Tribolium castaneum adults. Furthermore, for the estimation of the relationship between molecular descriptors and fumigant toxicity of plant volatiles, quantitative structural activity relationship (QSAR) models were developed using principal component analysis and multiple linear regression. Amongst the tested EOs, garlic EO was found to be the most toxic fumigant. The PCs toxicity analysis revealed that terpineol, limonene, linalool, and piperitone as potential fumigants to C. maculatus (< 20 µL/L air of LC50), limonene and piperitone as potential fumigants to T. castaneum (14.35 and 154.11 µL/L air of LC50, respectively), and linalool and piperitone as potential fumigants to S. oryzae (192.27 and 69.10 µL/L air of LC50, respectively). QSAR analysis demonstrated the role of various molecular descriptors of EOs and PCs on the fumigant toxicity in insect pest species. In specific, dipole and Randic index influence the toxicity in C. maculatus, molecular weight and maximal projection area influence the toxicity in S. oryzae, and boiling point and Dreiding energy influence the toxicity in T. castaneum. The present findings may provide insight of a new strategy to select effective EOs and/or PCs against stored product insect pests.

Bioactivities and Synergistic Effect of Elsholtzia ciliata Essential Oil and Its Main Components against Lasioderma serricorne.

Investigations have shown that storage bugs seriously harm grains during storage. In the interim, essential oils (EOs) have been proven to be a good botanical pesticide. The anti-Lasioderma serricorne properties of Elsholtzia ciliata essential oil, which was obtained by steam distillation, were evaluated using DL-limonene, carvone, and their two optical isomer components using contact, repelling, and fumigation techniques. Simultaneously, the fumigation, contact, and repellent activities of carvone and its two optical isomers mixed with DL-limonene against L. serruricorne were evaluated. The results showed that E. ciliata, its main components (R-carvone, DL-limonene), and S-carvone exhibited both fumigations (LC50 = 14.47, 4.42, 20.9 and 3.78 mg/L) and contact (LD50 = 7.31, 4.03, 28.62 and 5.63 µg/adult) activity against L.serricorne. A binary mixture (1:1) of R-carvone and DL-limonene displayed an obvious synergistic effect. A binary mixture (1:1) of carvone and its two optical isomers exhibited an obvious synergistic effect, too. Furthermore, the repellent activity of the EO, carvone, and its two optical isomers, DL-limonene, and a combination of them varied. To stop insect damage during storage, E. ciliata and its components can be utilized as bio-insecticides.

Metals/bisulfite system involved generation of 24-sulfonic-25-ene ginsenoside Rg1, a potential quality control marker for sulfur-fumigated ginseng.

Ginseng is a most popular health-promoting food with ginsenosides as its main bioactive ingredients. Illegal sulfur-fumigation causes ginsenosides convert to toxic sulfur-containing derivatives, and reduced the efficacy/safety of ginseng. 24-sulfo-25-ene ginsenoside Rg1 (25-ene SRg1), one of the sulfur-containing derivatives, is a potential quality control marker of fumigated ginseng, but with low accessibility owing to its unknown generation mechanism. In this study, metals/bisulfite system involved generation mechanism was investigated and verified. The generation of 25-ene SRg1 in sulfur-fumigated ginseng is that SO2, formed during sulfur-fumigation, reacted with water and ionized into HSO3-. On the one hand, under the metals/bisulfite system, HSO3- generates HSO5- and free radicals which converted ginsenoside Rg1 to 24,25-epoxide Rg1; on the other hand, as a nucleophilic group, HSO3- reacted with 24,25-epoxide Rg1 and further dehydrated to 25-ene SRg1. This study provided a technical support for the promotion of 25-ene SRg1 as the characteristic quality control marker of sulfur-fumigated ginseng.

Encapsulated allyl isothiocyanate improves soil distribution, efficacy against soil-borne pathogens and tomato yield.

BACKGROUND: Crop quality, yield and farmer income are reduced by soil-borne diseases, nematodes and weeds, although these can be controlled by allyl isothiocyanate (AITC), a plant-derived soil fumigant. However, its efficacy against soil-borne pathogens varies, mainly because of its chemical instability and uneven distribution in the soil. Formulation modification is an effective way to optimize pesticide application. We encapsulated AITC in modified diatomite granules (GR) and measured the formulation's loading content and stability, environmental fate and efficacy against soil-borne pathogens, and its impact on the growth and yield of tomatoes. RESULTS: We observed that an AITC loading content in the granules of 27.6% resulted in a degradation half-life of GR that was 1.94 times longer than 20% AITC emulsifiable concentrate in water (EW) and shorter than AITC technical (TC) grade. The stable and more even distribution of GR in soil resulted in relatively consistent and acceptable control of soil-borne pathogens. Soil containing AITC residues that remained 10-24 days after GR fumigation were not phytotoxic to cucumber seeds. GR significantly reduced soil-borne pest populations, and tomato growth and yield increased as AITC dosage increased. GR containing an AITC dose of 20 g m-2 effectively controlled pathogens in soil for about 7 months and improved tomato yield by 108%. CONCLUSION: Our research demonstrates the benefits of soil fumigation with loaded AITC over other formulations for effective pest control, and improved tomato plant growth and fruit yield. Fumigant encapsulation appears to be a useful method to improve pest and disease control, environmental performance and fumigant commercial sustainability. © 2024 Society of Chemical Industry.

Impacts of the Ban on the Soil-Applied Fumigant Methyl Bromide.

The loss of the soil fumigant methyl bromide (MeBr) and adoption of soil fumigant alternatives has been challenging for farmers, particularly for those crops in which pathogens previously controlled by MeBr have emerged as significant problems, but it has resulted in some unanticipated benefits for the scientific community and the environment. Applauded as one of the most effective environmental agreements to date, the universally accepted Montreal Protocol on Ozone Depleting Substances has had a significant impact on the environment, reducing the release of halogenated compounds from anthropogenic sources enough to mitigate global warming by an estimated 1.1°C by 2021. The funding associated with various MeBr transition programs has increased collaboration across scientific disciplines, commodity groups, industry, and regulatory agencies. Chemical alternatives and improved application strategies, including the development of gas-retentive agricultural films, coupled with sound efficacy data and grower ingenuity have resulted in the sustained production of many of the impacted crops; although there has been some loss of acreage and value, particularly for Florida fumigated crops, for some, value has continued to increase, allowing production to continue. The loss of a single, broad-spectrum tool for pest control has led to a deeper understanding of the specific pest complexes impacting these at-risk crops, as well as the development of new, biologically based management tools for their control while increasing our understanding of the role of the soil microbiome in pest control and crop production.

Fumigation Using 1,3-Dichloropropene Manages Meloidogyne enterolobii in Sweetpotato More Effectively than Fluorinated Nematicides.

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.

Improvement in the quality and productivity of Codonopsis pilosula seedlings by dazomet soil fumigation.

Dazomet is a dry powder formulation that releases toxic gas containing methyl isothiocyanate, which controls soil-borne pests and weeds, improving crop yields when applied to moist soils. To explore the efficacy of dazomet fumigation in the cultivation of the perennial herb Codonopsis pilosula, four typical cultivars (G1, G2, W1 and TCK) in Gansu Province were selected for seedling cultivation after soil fumigation (F) by dazomet, and non-fumigated soil was used as a control (CK). The experiments took 2 years to complete. The functional diversity of the soil enzymes and microorganisms, seedling emergence and physiological characteristics, and the quality and yield of Codonopsis seedlings and Radix were assessed. The results showed that the seed emergence rate, seedling re-green rate and several antioxidant enzymatic activities improved in the treatments involving soil fumigation with dazomet, and membrane lipid peroxidation in the seedlings decreased. On average, compared with those of the respective controls, the root viability and yield of the seedlings of the tested cultivars also increased by 34.87% and 42.4%, respectively, and the incidence of root rot in the seedlings was reduced by 83.9%, compared with their respective controls. After harvest, the yield increased by 23.9%, the incidence of root rot decreased by 61.3%, increase in yield and a 61.3% reduction in incidence, and the medicinal materials were determined to be safe and residue-free. The effects of fumigation were cultivar-specific and were especially prominent in G2. Therefore, soil fumigation with dazomet could improve the quality and productivity of Codonopsis pilosula seedlings. Taken together, these findings suggest that when herbs are bred by seedling transplantation, especially cultivars of good quality but poor resistance or species with rare germplasm resources, soil fumigation provides a way to improve cultivation effectiveness and, more importantly, ensures the probability of successfully breeding the species.

Impact of repeated fumigant applications on soil properties, crop yield, and microbial communities in a plastic-mulched tomato production system.

Pre-plant soil fumigation is widely applied to control nematodes, soil-borne fungal pathogens, and weeds in vegetable crops. However, most of the research evaluating the effect of fumigants on crop yield and soil microbial communities has been done on single compounds despite growers mainly applying fumigant combinations. We studied the effect of different fumigant combinations (chloropicrin, 1,3-dichloropropene, and metam potassium) on soil properties, crop yield, and the soil bacterial and fungal microbiome for two consecutive years in a plastic-mulched tomato production system in Florida (United States). While combinations of fumigants did not improve plant productivity more than the individual application of these products, application of fumigants with >60 % chloropicrin did significantly increase yield. Fumigant combinations had no significant effect on bacterial diversity, but fumigants with >35 % chloropicrin reduced soil fungal diversity and induced temporary changes in the soil bacterial and fungal community composition. These changes included short-term increases in the relative abundance of Firmicutes and Ascomycota, as well as decreases in other bacterial and fungal taxa. Repeated fumigation reduced network complexity and the relative abundance of several predicted bacterial functions and fungal guilds, particularly after fumigation and at end of harvest (3-months post fumigation). A structural equation model (SEM) showed fumigants not only directly impact crop yield, but they can also indirectly determine variations in plant productivity through effects on the soil microbiome. Overall, this study increases our understanding of the environmental and agricultural impacts of fumigants in a plastic-mulched tomato production system.

Fumigation alters the manganese-oxidizing microbial communities to enhance soil manganese availability and increase tomato yield.

Manganese is one of the essential trace elements for plants to maintain normal life activities. Soil fumigation, while effectively controlling soil-borne diseases, can also improve the cycling of soil nutrient elements. MiSeq amplicon sequencing is used to determine the composition of soil microbial communities, and structural equation modeling and the random forest algorithm are employed to conduct a correlation analysis between key manganese-oxidizing microorganisms and soil manganese availability. This experiment investigated the microbial mechanisms behind the observed increase in available manganese in soil after fumigation. The key findings revealed that Bacillus, GeoBacillus, GraciliBacillus, Chungangia, and Pseudoxanthomonas play crucial roles in influencing the variation in soil available manganese content. Fumigation was found to elevate the abundance of Bacillus. Moreover, laccase activity emerged as another significant factor impacting soil manganese availability, showing an indirect correlation with available manganese content and contributing to 58 % of the observed variation in available manganese content. In summary, alterations in the communities of manganese-oxidizing microorganisms following soil fumigation are pivotal for enhancing soil manganese availability.

Unveiling the Chemical Composition of Sulfur-Fumigated Herbs: A Triple Synthesis Approach Using UHPLC-LTQ-Orbitrap MS-A Case Study on Steroidal Saponins in Ophiopogonis Radix.

Ophiopogonis Radix (OR) is a traditional Chinese medicine. In recent years, in order to achieve the purpose of drying, bleaching, sterilizing and being antiseptic, improving appearance, and easy storage, people often use sulfur fumigation for its processing. However, changes in the chemical composition of medicinal herbs caused by sulfur fumigation can lead to the transformation and loss of potent substances. Therefore, the development of methods to rapidly reveal the chemical transformation of medicinal herbs induced by sulfur fumigation can guarantee the safe clinical use of medicines. In this study, a combined full scan-parent ions list-dynamic exclusion acquisition-diagnostic product ions analysis strategy based on UHPLC-LTQ-Orbitrap MS was proposed for the analysis of steroidal saponins and their transformed components in sulfur-fumigated Ophiopogonis Radix (SF-OR). Based on precise mass measurements, chromatographic behavior, neutral loss ions, and diagnostic product ions, 286 constituents were screened and identified from SF-OR, including 191 steroidal saponins and 95 sulfur-containing derivatives (sulfates or sulfites). The results indicated that the established strategy was a valuable and effective analytical tool for comprehensively characterizing the material basis of SF-OR, and also provided a basis for potential chemical changes in other sulfur-fumigated herbs.

Evaluation of fumigant toxicity of cyclohexanone to 5 species of insect pests.

Cyclohexanone is a major precursor for nylon production and is also used as a pesticide solvent. In this study, cyclohexanone was evaluated as a fumigant against rice weevil adults, confused flour beetle adults, western flower thrips larvae and adults, spotted wing drosophila adults, and subterranean termite workers. Cyclohexanone fumigation was effective against all 5 insects, and there were considerable variations in susceptibility to cyclohexanone fumigation among the 5 species. At 20 °C, complete control of spotted wing drosophila adults was achieved in 1-h fumigation with 25 µl/l of cyclohexanone and complete control of eastern subterranean termite workers was achieved in 3-h fumigations with 50 µl/l dose of cyclohexanone. Stored-product insects confused flour beetle, and rice weevil adults were more tolerant to cyclohexanone fumigation. Fumigations of 24 h with 75 µl/l dose of cyclohexanone caused 100% mortality of rice weevil adults and 98% mortality of confused flower beetle adults. Even at a 100 µl/l dose, the 24-h fumigations did not achieve 100% mortality of confused flour beetle adults. At 5 °C, complete control of western flower thrips was achieved in 3- and 6-h fumigations with 100 and 50 µl/l doses of cyclohexanone, respectively. Cyclohexanone vapor concentrations were measured using cyclohexanone detector tubes. Vapor concentrations were far below the expected saturation concentration indicating that most cyclohexanone did not exist as vapor in fumigation chambers. The results of effective control of all 5 insect species suggest that cyclohexanone has the potential to be used as a fumigant for postharvest pest control.

Crop bromide concentrations following methyl bromide fumigation for pale cyst nematode in southeastern Idaho.

Methyl bromide (MeBr) is a sterilizing fumigant used to control quarantine pests that is restricted due to its detrimental atmospheric effects. The degradation of injected MeBr produces crop-available Br- . Up to five applications of MeBr were used in southeastern Idaho fields to combat the pale cyst nematode (Globodera pallida). Data regarding the uptake and partitioning of Br- in crops following MeBr application in the region were unavailable. Research determined background concentrations of Br- in alfalfa (Medicago sativa L.), barley (Hordeum vulgare L.), corn (Zea mays L.), potato (Solanum tuberosum L.), and wheat (Triticum aestivum L.) compared to MeBr-treated fields. Background Br- concentrations ranged from nondetectable (ND) to 33.0 mg Br- kg-1 ; vegetative tissue concentrations were greater than reproductive, except corn where there was no difference. Nearly all crops grown in MeBr-treated fields had greater Br- concentrations than background. Background-baled-alfalfa tissue Br- concentration was 33.0 mg kg-1 compared to 117.8 mg Br- kg-1 from a MeBr-treated field. Br- concentration in green alfalfa decreased from 79.8 to 36.5 mg Br- kg-1 at the final cutting in a MeBr-treated field, where time after application decreased crop Br- concentrations. Small grains had low Br- concentrations in reproductive tissue (1.7 mg Br- kg-1 ) compared to vegetative tissue (106.5 mg Br- kg-1 ). Corn stover concentration (12.7 mg Br- kg-1 ) was low relative to small-grain straw, but corn ear (5.8 mg Br- kg-1 ) was greater than small-grain reproductive tissue in the MeBr-treated field. Crop selection following MeBr applications should consider the likelihood of elevated Br- concentration for the plant fractions intended end use.

Key taxa and mobilome-mediated responses co-reshape the soil antibiotic resistome under dazomet fumigation stress.

Agrochemicals are emergingly being implicated in the widespread dissemination of antibiotic resistance genes (ARGs) in agroecosystems. However, minimal research exists on the disturbance of fumigant on soil ARGs. Focusing on a typical fumigant dazomet in a simulated soil microcosm, we characterized the dazomet-triggered timely response and longstanding dynamic of ARGs at one-fold and two-fold field recommended doses using metagenome and quantitative PCR. Dazomet treatments reduced 13.17%-69.98% of absolute abundance of 16S rRNA gene and targeted ARGs, but, awfully, boosted diversity and relative abundance of ARGs up to 1.33-1.60 and 1.62-1.90 folds, respectively. Approximately 77.28% of changes in relative abundance of ARGs could be explained by bacterial community and mobile genetic elements (MGEs). Mechanistically, primary hosts of ARGs shifted from Proteobacteria (control) to Firmicutes and Actinobacteria (treatments) accompanied with corresponding changes in their abundance by combining community analysis, host tracking analysis and antibiotic resistant bacteria assay. Meanwhile, dazomet exposure significantly increased the incidence of MGEs and stimulated the conjugation of antibiotic-resistant plasmid. In addition, absolute abundance of targeted ARGs gradually recovered in the post-fumigation stage. Collectively, our results elucidate the dazomet-triggered emergence and spread of soil ARGs and highlight the importance of navigating toward rational use of fumigant in agricultural fields.

Development and characteristics of auricular fumigation moxibustion combined with heat-sensitive moxibustion device. / è€³ç†ç¸è”åˆçƒ­æ•ç¸è£ ç½®çš„ç ”åˆ¶ä¸Žç‰¹ç‚¹.

A moxibustion device with the functions of auricular fumigation moxibustion and heat-sensitive moxibustion is designed. The smoke of the ignited moxa stick is used for the fumigation moxibustion at the external auditory canal, while the heat generated works on Dazhui (GV 14) for heat-sensitive moxibustion. The device consists of five parts, i.e. combustion chamber, smoke pipe, smoke processing chamber, power module and connector. It solves the limitations such as unpleasant experience in treatment, unfavorable temperature control, easy scalding and excessive manual dependence induced by usual fumigation moxibustion and during heat-sensitive moxibustion. This moxibustion device may improve the safety and convenience when delivering the treatment with fumigation moxibustion and heat-sensitive moxibustion, as well as the work efficiency of medical staff.

Effects of Fumigation on the Reduction of Salmonella enterica in Soil.

Due to the phaseout of methyl bromide (MeBr), there is a need for broad-spectrum soil fumigation alternatives for pest management. Little is known about the impact of fumigation alternatives on foodborne pathogens, such as Salmonella, in agricultural soils. This study investigated the effect of MeBr alternative fumigants on Salmonella reduction in soil. Sandy loam soil was collected from a conventional farmed vegetable field and inoculated with either Salmonella Newport J1892 or Typhimurium ATCC 14028 (5.9 ± 0.3 log10 colony-forming unit [CFU]/g). Each of the four fumigants labeled for pest management (1,3-dichloropropene, chloropicrin, dimethyl disulfide, and metam sodium) was applied at labeled maximum application field levels to soil in pots and stored for a 2-week period. Sterile water was used as a control. Following the 2-week period, Salmonella concentrations in soil samples were enumerated at 1, 7, 14, and 21 days postfumigation. The mean concentration of Salmonella Newport was significantly higher than that of Salmonella Typhimurium 1 day after fumigation (p = 0.015). Fumigation using 1,3-dichloropropene or dimethyl disulfide significantly reduced Salmonella Newport and Salmonella Typhimurium concentrations, compared with the sterile water control. The rate of Salmonella reduction in soil treated with dimethyl disulfide was higher (0.17 ± 0.02 log10 CFU/g/day), compared with soil treated with the other fumigants (0.10-0.12 log10 CFU/g/day). Due to the reduction of Salmonella, alternative fumigation treatments may mitigate potential Salmonella contamination in soil within farm environments.

Effects of allyl isothiocyanate fumigation on medicinal plant root knot disease control, plant survival, and the soil bacterial community.

BACKGROUND: Allyl isothiocyanate (AITC) is a natural product with high volatility that is used as a biofumigant to alleviate soil-borne plant diseases, and problems such as root knot nematodes (RKNs) that necessitate continuous cropping. However, little research has assessed the effects of AITC fumigation on medicinal plants. RESULTS: AITC significantly reduced the population of RKNs in soil (p < 0.0001) and showed an excellent RKN disease control effect within 6 months after sowing Panax notoginseng (p < 0.0001). The seedling survival rate of 2-year-old P. notoginseng was approximately 1.7-fold higher after soil treatment with AITC (p = 0.1008). 16S rRNA sequencing indicated that the AITC treatment affected bacterial richness rather than diversity in consecutively cultivated (CC) soil. Furthermore, biomarkers with statistical differences between AITC-treated and untreated CC soil showed that Pirellulales (order), Pirellulaceae (family), Pseudomonadaceae (family), and Pseudomonas (genus) played important roles in the AITC-treated group. In addition, the microbiome functional phenotypes predicted using the BugBase tool suggested that AITC treatment is more conducive to improving CC soil through changes in the bacterial community structure. Crucially, our research also suggested that AITC soil treatment significantly increases soil organic matter (p = 0.0055), total nitrogen (p = 0.0054), and available potassium (p = 0.0373), which promotes the survival of a succeeding medicinal plant (Polygonatum kingianum). CONCLUSION: AITC is an ecologically friendly soil treatment that affects the top 10 bacterial richness but not diversity. It could also provide a basis for a useful agricultural soil management measure to alleviate soil sickness.