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Iodide‐bound ruthenium‐JOSIPHOS complexes catalyze the redox‐neutral C−C coupling of primary alcohols with methylallene (1,2‐butadiene) or 1,3‐butadiene to form products of anti‐crotylation with good to excellent levels of diastereo‐ and enantioselectivity. Distinct from other methods, direct crotylation of primary alcohols in the presence of unprotected secondary alcohols is possible, enabling generation of spirastrellolide B (C9–C15) and leucascandrolide A (C9–C15) substructures in significantly fewer steps than previously possible. [ABSTRACT FROM AUTHOR]

Chemical control, especially fumigants, is the most used method to control stored-grain pests. A safer alternative for disinfestation is to heat grains to a temperature of 50-60oC. However, this alternative consumes high thermal energy due to the relatively high temperature required to achieve the required goal. In the present paper, a grain solar heating system has been developed to achieve this high temperature/short time technique to control Callosobruchus maculatus, one of the most common pests of many legumes. The solar heating system provides an attractive alternative to conventional electric heating systems or gas-fired heating systems. The present results show that the proposed system is successful in suppressing C. maculatus population within 115 min under temperatures from 55 to 57oC. This thermal range is capable of controlling most of the stored grain insects. Employing solar heating provides a simple, energy-saving alternative to small and medium-scale applications. [ABSTRACT FROM AUTHOR]

Simple Summary: Storage arthropods may invade and damage many types of stored commodities, both in developing and developed countries. The continuous worldwide usage of phosphine as a major fumigant for stored grain protection has led to the development of resistance by several major stored-product insect species. There are data on the occurrence of phosphine resistance from different pest species originating from multiple countries and geographical areas, especially in countries that are among the major grain producers in the world. However, the ongoing EU project (novIGRain) has recently enabled a resistance survey of the selected key species of stored-product pests in some EU countries, including the Czech Republic. The presented part of the survey in this publication included more than fifty field populations of the rice weevil, Sitophilus oryzae, the lesser grain borer, Rhyzopertha dominica, and the saw-toothed grain beetle, Oryzaephilus surinamensis, collected in Czech farm grain stores. It was found that the tested Czech populations of O. surinamensis have a relatively lower frequency and level of resistance than the populations of S. oryzae and R. dominica. Based on our results, the occurrence of resistance to phosphine in the Czech Republic is widespread and includes economically important species, which highlights the need for fumigation alternatives as well as the establishment of integrated resistance management programs. Phosphine is globally the most widely adopted fumigant for the control of storage pests. Recently, an increase in the frequency of stored-product pest resistance has been observed with significant geographical and interspecific variations. In this context, there are available data for the occurrence of resistant populations from America, Asia, Africa, and Australia, but there are few data in the case of Europe. Therefore, the aim of this work was to evaluate phosphine efficacy in important beetle pests of stored products, i.e., Sitophilus oryzae (L.), Oryzaephilus surinamensis (L.), and Rhyzopertha dominica (F.) sampled from the Czech Republic, using a rapid diagnostic test that is based on the speed to knockdown after exposure. Apart from the standard laboratory populations, which were used as the controls, we tested 56 field populations of these three species, collected in Czech farm grain stores. The survey revealed that 57.1% of the tested field populations were classified as phosphine-susceptible, based on the knockdown method used. However, profound variations among species and populations were recorded. The species with the highest percentage of resistant populations was R. dominica (71.4% of the populations; resistance coefficient 0.5–4.1), followed by S. oryzae (57.1% of the populations; resistance coefficient 0.8–6.9), and O. surinamensis (9.5% of the populations; resistance coefficient 0.5–2.9). Regarding the intra-population variability in response to phosphine (slope of the knockdown time regression), the laboratory and slightly resistant populations of all species were homogenous, whereas the most resistant populations were strongly heterogeneous. Our data show that the occurrence of resistance in the Czech Republic is relatively widespread and covers a wide range of species, necessitating the need for the adoption of an action plan for resistance mitigation. [ABSTRACT FROM AUTHOR]

A reliable and efficient palladium‐catalyzed cascade cyclization/alkylation of oxime ethers with unactivated alkenes is described, affording a whole variety of structurally diverse isoxazole derivatives in moderate to good yields with excellent functional group compatibility. Ionic liquid [Aeim]Br not only acts as an environmentally friendly solvent but also acts as an accelerating agent to provide excess bromine source to eliminate bromomethane from oxime ethers. More importantly, the use of "chain‐walking" strategy provides a novel methodology in organic synthesis to rapid generation of molecular complexity from readily available starting materials. [ABSTRACT FROM AUTHOR]

BACKGROUND: The protection of grains from insect infestation is critical during storage. Insect repellent pellets (IRPs) are a potential technique to repel insects by hindering insect movement toward the grains. The basic principle of IRPs is the use of active components found in the oils of lemongrass, eucalyptus, and neem leaves for the controlled release of fumes, thereby avoiding the need for reapplication after a few days. Here, we examined the antifungal activity, the lethal dose, and the repelling effect of IRPs against red flour beetle, Tribolium castaneum, over a 30 day period. RESULTS: We observed that IRPs possessed antifungal properties and were able to repel the adults of T. castaneum. These insects ultimately died from the fumes if they manage to stay near the IRPs (LD50 = 2 and LD99 = 7 days). The active components (phenol, 2,4‐di‐tert‐butyl‐, citral, neral, geraniol, n‐hexadecanoic acid) present in IRP during the initial stage were also found after a storage period of 35 days. CONCLUSION: The active components present in IRPs have antifungal, repellent, and fumigant properties. The IRPs can thus be termed potent botanical insecticides and are an alternative to synthetic insecticides. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The fumigation treatment with oregano essential oil (OEO) was applied to inactivate Aspergillus flavus (A. flavus) and its mechanism was studied. Results indicated that the minimal fungicidal concentration (MFC) of OEO vapor was lower than OEO dissolved in liquid medium. Indeed, OEO vapor at MFC resulted in the abnormal branching of A. flavus mycelium. Further, the fumigation time at MFC required for fungicidal effect was reduced from 7 days to 8 h by enhancing the fumigation temperature from 28 to 45°C. Meanwhile, the mechanism of action might be the oxidative stress in response to OEO vapor within the cells of A. flavus mycelium. Results suggested increased lipid peroxidation and O2− production as well as SOD/CAT activity, eventually leading to decreased mitochondrial activity and ATP production. Additionally, OEO vapor inhibited metabolic activities related to the synthesis of protein and methylglyoxal as well as aflatoxin production. Novelty impact statement: OEO exhibited a higher fungicidal effect on A. flavus mycelium compared to its spores. OEO fumigation exhibited an inhibitory effect on the metabolic synthesis of A. flavus. OEO fumigation induced oxidative stress and decreased mitochondrial activity. [ABSTRACT FROM AUTHOR]

Experiments were established to evaluate the efficacy of currently available nonfumigant chemical and biological nematicides against nematode communities in peach orchards in two different geographic regions of South Carolina: the Upstate and Ridge. The treatments included sole or mixed application of two chemical nematicides (oxamyl and fluopyram) and a biological nematicide (Majestene) plus an untreated control. Ring nematode and lesion nematode were predominant in Upstate and Ridge orchards, respectively. Fluopyram was the most effective nematicide in the Upstate orchard, and it reduced plant-parasitic nematodes by 69% relative to the untreated control at 3 months postapplication. Similarly, fluopyram and oxamyl suppressed 74 to 87% of plant-parasitic nematodes in the Ridge orchard at 2 months postapplication. Significant effects of Majestene on plant-parasitic nematodes was not observed. Mixed applications of nematicides were also effective in suppressing plant-parasitic nematodes although the suppressions were not always significant from sole applications or the control. The chemical nematicides significantly reduced free-living nematodes in the first 2 months following their applications in the Ridge orchard, the reductions ranging from 60 to 79% relative to the control. However, free-living nematode populations quickly rebounded to the highest level in 3 months following the nematicide applications. Free-living nematode communities in the Upstate orchard did not experience any significant effects of nematicides until 4 months following nematicide application; at that time there was a 60 to 68% decline in populations. Results from this study suggest that the nonfumigant nematicides can only provide a short-term management of plant-parasitic nematodes in peach. [ABSTRACT FROM AUTHOR]

Currently, the majority of fresh apricots destined for the production of dried apricots undergo sulphur oxide fumigation before drying to protect the fruit against fungal spoilage. To eliminate the use of sulphite, packaging assisted with essential oil is a promising strategy to increase shelf-life of dried apricots since it does not impact its flavor characteristics. In this study, three essential oils were selected: clove, lemongrass and thyme. They were screened for antifungal activity against Eurotium spp. with different methods: micro- and macro-dilution and agar-diffusion. Growth/no-growth data were used to develop models for all three methods. Clove exerted the strongest antifungal activity with an inhibitory concentration of 0.075%, 0.035% and 0.05% through respectively micro-dilution, macro-dilution and agar diffusion. For thyme the following values were obtained: 0.775%, 0.070% and 0.100%. This means that the antifungal activity of thyme is 10 times lower in micro-dilution and 2 times lower in macro-dilution and agar diffusion compared to clove. Through micro-dilution, lemongrass was found to have the second highest antifungal activity (0.25%). When used in the volatile atmosphere of dried apricots and in macro-dilution, the antifungal activity of lemongrass was the lowest, with respective values of > 0.200% and 0.105% for G/NG prediction. [ABSTRACT FROM AUTHOR]

Featured Application: Pseudococcus comstocki, a quarantine pest, was completely killed when fumigated with liquid ethyl formate (EF), without any phototoxicity or alterations in the internal condition of the grapes (Campbell Early), at EF 70 g/m3 for 4 h, 145.85 g h/m3 with a loading ratio of 10% at 5 °C. EF can be an alternative to methyl bromide (MB) in terms of safety in the workplace as well as preventing ozone depletion. Mealybugs found on grapes during quarantine in Korea are fumigated with methyl bromide (MB). However, MB is an ozone-depleting, highly toxic pesticide; therefore, the International Plant Protection Convention, a representative organization involved in quarantine, recommends using MB alternatives. We evaluated the feasibility of using liquid ethyl formate (EF), a new EF formulation, to control mealybugs (Pseudococcus comstocki) on grapes (Campbell Early). Large-scale tests and the comparative evaluation of EF and MB desorption from grapes were conducted during the simulated 72-h post-fumigation period. Dose–response tests showed that the EF concentration and time product causing 99% mortality (LCt99) at 5 °C was 47.36 and 145.85 g h/m3 for adults and eggs, respectively. EF treatment at 70 g/m3 for 4 h at 5 °C with a loading ratio of 10% achieved an LCt99 of 145.85 g h/m3 on P. comstocki, confirming EF efficacy on mealybugs without phytotoxic effects on grapes. EF fumigation may also be safer because EF concentrations were maintained at less than 100 ppm, the specified exposure limit of EF; meanwhile, those of MB were higher than the exposure limit (1 ppm). Therefore, liquid EF can be used as a safer alternative to MB in phytosanitary treatments of grapes to control P. comstocki. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sclerotium rot causes damping-off and stem rot in seedlings and mature mungbeans, which negatively impacts cultivation. The use of a rhizobacterium to control soil-borne diseases is an alternative method to the excess use of synthetic fungicides; therefore, this study aims to screen rhizosphere actinobacteria with fungicidal activities against Sclerotium rolfsii, the pathogen that causes sclerotium rot in mungbeans. Primary screening showed that the Streptomyces sp. isolate Z1-04-02 displayed the highest effectiveness against S. rolfsii in dual culture plates, with a percentage inhibition of 74.28%. An assay containing enzymes that degrade cell walls, of the cell-free culture filtrate (CF) of Z1-04-02, showed that the activities of chitinase and β-1,3-glucanase were 0.0209 and 1.0210 U/mL, respectively, which was significantly higher than that of the control (media alone). The cell-free CF of Z1-04-02, incubated at 37 °C and 100 °C, using agar well diffusion, effectively inhibited the growth of S. rolfsii with inhibition percentages of 37.78% and 27.78%, respectively. Solid-phase microextraction (SPME) was applied to trap volatiles released from Z1-04-02 and gas chromatography–mass spectrometry (GC/MS); volatile antifungal compounds were tentatively identified as bicyclic monoterpene (1R)-(-)-myrtenal. The application of the cell-free CF, and the spore suspension of Z1-04-02, showed disease severity indexes (DSIs) of 12.5% and 8.25%, respectively, which were significantly lower than those showing inoculation by S. rolfsii alone. The identification of this strain by morphology, biochemistry tests, and 16s rDNA sequences revealed that Z1-04-02 was Streptomyces albulus. This finding revealed that S. albulus Z1-04-02 displayed diverse fungicidal activities against S. rolfsii, and it has the potential to act as a biological control agent in terms of inhibiting sclerotium rot in mungbeans. [ABSTRACT FROM AUTHOR]

BACKGROUND: Double‐cropping is a common practice in vegetable plasticulture whereby a second crop is planted on the same plastic bed as the first crop. Root‐knot nematodes (Meloidogyne spp.) are one of the major soilborne constraints in double‐cropped vegetables due to nematode population build‐up on the first crop. We evaluated the effect of fumigant and non‐fumigant nematicides applied on the first crop, on nematode infection and yield of the second crop in 10 field trials between 2017 and 2020. Fumigants were chloropicrin (Pic100), chloropicrin +1,3‐D (PicClor60), and non‐fumigant nematicides were oxamyl (Vydate), fluensulfone (Nimitz), fluopyram (Velum) and fluazaindolizine (Salibro). The first crop was tomato and double crops were cucumber, squash, zucchini, and cantaloupe. RESULTS: Fumigation with chloropicrin on the first crop increased root‐knot nematode damage on the double‐crop at the end of the season in seven trials, while the opposite was noted in one trial, and no difference was noted in two trials. Fumigation with chloropicrin+1,3‐D resulted in root‐knot nematode damage less than chloropicrin but more than non‐fumigated plots. Cucurbit yield was greater in non‐fumigated beds in four trials, and in chloropicrin‐treated beds in two trials. Fluensulfone reduced root‐knot nematode damage on the second crop in five out of 10 trials. CONCLUSION: Our results indicate that chloropicrin applied on the tomato crop may lead to increased root‐knot nematode damage on the double crop. More research is needed to understand the processes behind this, but it is possibly related to a reduction in natural nematode soil suppressiveness due to the broad‐spectrum fungicidal activity of chloropicrin. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Arbuscular mycorrhizal fungi (AMF) have the potential to reduce the deleterious effect of soil-borne pathogens, but their ability for pathogen biocontrol may vary depending on the genotype of the plant, the pathogen, and the AMF interaction. Thus, the aim of this work was to evaluate the effect of the Mexican biofertilizer Rizofermic-UV based on a mix of AMF formulation against the common bean root rot caused by the pathogenic fungus Rhizoctonia solani Kūhn 1858 (Teleomorph: Thanatephorus cucumeris). Additionally, the total phenolic content, individual phenolic acid (caffeic, ferulic, o-cumaric, p-cumaric, sinapic, and vanillic), and the flavonoid (catechin, kaempherol, quercetin, and rutin) profiles were analyzed. Our results show that the AMF biofertilization reduces the disease severity up to 68 %, and this was accompanied by a boost in total phenolic content in dual inoculation. Furthermore, a variation in the individual phenolic profiles caused by both AMF interaction and pathogen treatment alone were observed. In dual inoculations, vanillic acid was significantly different among treatments, suggesting it may contribute to the enhanced resistance of mycorrhizal roots to soil-borne pathogens. Further work is required to elucidate the exact role of these compounds in the bioprotection of arbuscular mycorrhizal to plant pathogens. [ABSTRACT FROM AUTHOR]

The amount of atmospheric nitrogen-containing aerosols has increased dramatically due to the globally rising levels of nitrogen from fertilization and atmospheric deposition. Although the balance of carbon and nitrogen in plants is a crucial component of physiological and biochemical indexes and plays a key role in adaptive regulation, our understanding of how nitrogen-containing aerosols affect this remains limited; in particular, regarding the associated mechanisms. Using a fumigation particle generator, we generated ammonium nitrate solution (in four concentrations of 0, 15, 30, 60 kg N hm−2 year−1) into droplets, in 90% of which the diameters were less than 2.5 μm, in the range of 0.35–4 μm, and fumigated Iris germanica L. and Portulaca grandiflora Hook. for 30 days in April and August. We found that the weight percentage of nitrogen in the upper epidermis, mesophyll tissue, and bulk of leaves decreased significantly with the N addition rate, which caused a decrease of carbon:nitrogen ratio, due to the enhanced net photosynthetic rate. Compared with Portulaca grandiflora Hook., Iris germanica L. responded more significantly to the disturbance of N addition, resulting in a decrease in the weight percentage of nitrogen in the roots, due to a lower nitrogen use efficiency. In addition, the superoxide dismutase activity of the two plants was inhibited with a higher concentration of nitrogen sol; a reduction of superoxide dismutase activity in plants means that the resistance of plants to various environmental stresses is reduced, and this decrease in superoxide dismutase activity may be related to ROS signaling. The results suggest that inorganic nitrogen-containing aerosols caused excessive stress to plants, especially for Iris germanica L. [ABSTRACT FROM AUTHOR]

The new scenario for global food production and supply is decidedly complex given the current forecast of an increase in food fragility due to international tensions. In this period, exports from other parts of the world require different routes and treatments to preserve the food quality and integrity. Fumigation is a procedure used for the killing, removal, or rendering infertile of pests, with serious dangers to human health. The most-used fumigants are methyl bromide and ethylene dibromide. It is important to bear in mind that the soil may contain bromide ions naturally or from anthropogenic source (fertilizers and pesticides that contain bromide or previous fumigations). Different methods (titrimetric, spectrophotometric, and fluorometric approaches) are available to rapidly determine the amount of bromide ion on site in the containers, but these are non-specific and with high limits of quantification. The increasing interest in healthy food, without xenobiotic residues, requires the use of more sensitive, specific, and accurate analytical methods. In order to help give an overview of the bromide ion scenario, a new, fast method was developed and validated according to SANTE 11312/2021. It involves the determination of bromide ion in cereals and legumes through ion chromatography–Q-Orbitrap. The extraction was performed by the QuPPe method, but some modifications were applied based on the matrix. The method described here was validated at four different levels. Recoveries were satisfactory and the mean values ranged between 99 and 106%, with a relative standard deviation lower than 3%. The linearity in the matrix was evaluated to be between 0.010 and 2.5 mg kg−1, with a coefficient of determination (R2) of 0.9962. Finally, the proposed method was applied to different cereals and legumes (rice, wheat, beans, lentils pearled barley, and spelt) and tested with satisfactory results in EUPT-SMR16 organized by EURL. [ABSTRACT FROM AUTHOR]

Featured Application: A new application of phosphine fumigation with cold treatment to control peach fruit moth larvae Carposina sasakii. The fumigation of apples using methyl bromide (MeBr) can cause severe deterioration in fruit quality. Moreover, maintaining the quality of apples during postharvest storage and eradicating pests, especially those involved in quarantine issues, are important for facilitating the export of apples, including the "Fuji" apple (Malus pumila var. "Fuji") in South Korea. In the present study, phosphine (PH3) fumigation as an alternative to MeBr was found to be more effective for the control of peach fruit moth larvae (Carposina sasakii), which had naturally infested Fuji apples, at a high temperature (25 °C) rather than at a low temperature (5 °C). To achieve the industry requirement of better-quality perishable commodities and meet quarantine guidelines for export, PH3 fumigation at the low temperature (5 °C) was followed by cold treatments at 3 ± 2 °C for 2 and 4 weeks, which led to higher efficacy than was achieved using PH3 at 5 °C alone. Given that chemical treatments, such as treatment with 1-methylcyclopropene, can inhibit ethylene synthesis, low-temperature PH3 fumigation for 72 h followed by 4 weeks of cold treatment could also extend the shelf life of apples and resolve known quarantine issues when used as an alternative to MeBr treatment. [ABSTRACT FROM AUTHOR]

BACKGROUND: The effectiveness of metam potassium, 1,3‐dichloropropene, chloropicrin, and different ratios of 1,3‐dichloropropene and chloropicrin on the reduction of natural and artificial inoculum of Macrophomina phaseolina were investigated in laboratory and field experiments. Additionally, a multivariate meta‐analysis with data from six field trials conducted in Florida from 2012 to 2018 was performed. RESULTS: In small‐plot field experiments using drip stakes, the highest rate (468 L ha−1) of metam potassium was most effective in controlling M. phaseolina in infected crowns buried at 15.2 cm from the point of fumigant injection, whereas none of the rates was able to reduce inoculum buried at 30.5 cm. In closed‐container experiments, use of the highest rate of 1,3‐dichloropropene (168 kg ha−1) resulted in the highest level of pathogen control. Different rates of chloropicrin also reduced inoculum when compared to the non‐treated control. 1,3‐dichloropropene + chloropicrin at different ratios were also highly effective in controlling M. phaseolina. Results from the meta‐analysis of open‐field experiments indicated that metam potassium and 1,3‐dichloropropene + chloropicrin (63:35, v:v) treatments were significantly more effective in reducing M. phaseolina than the 1,3‐dichloropropene + chloropicrin (39:60, v:v) treatment; however, metam potassium was not as effective at the side of the beds. CONCLUSION: 1,3‐dichloropropene alone and in mixture with chloropicrin were more effective in reducing inoculum of M. phaseolina than chloropicrin alone, indicating the fungicidal efficacy of 1,3‐dichloropropene. Formulation with higher 1,3‐dichloropropene concentration performed better than the formulation with higher chloropicrin concentration in field trials. Metam potassium was effective when applied at the highest rate, but with limited lateral movement perpendicular to the drip irrigation line. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Soil-transmitted helminths are intestinal worm diseases transmitted through the soil. Available treatments are albendazole and/or ivermectin. The co-administration of existing drugs is an appropriate strategy. A fixed-dose combination adds practical advantages mainly considering mass drug administration. The aim is to characterize pharmacokinetics and to evaluate the comparative bioavailability of an innovative fixeddose combination of ivermectin/albendazole 18/400 mg compared with the marketed references. Seventy-eight healthy volunteers were included in this laboratory-blinded, randomized, three-treatment, three-period crossover study. Each subject received a single dose of ivermectin/albendazole 18/400 mg (1 tablet); ivermectin 3mg (6 tablets); and albendazole 400 mg (1 tablet). Serial blood samples for the pharmacokinetic analysis were obtained pre-dose and up to 72 h post-dose. Plasma concentrations of ivermectin H2B1a, ivermectin H2B1b, albendazole, and albendazole sulfoxide were analyzed by LCMS/ MS. Pharmacokinetic parameters were estimated by a non-compartmental analysis and bioavailability compared through a bioequivalence analysis. Safety and tolerability were assessed throughout the study. Main pharmacokinetic parameters of the fixed combination were estimated for both, ivermectin [Cmax (mean, confidence interval): 86.40 (30.42-39.23) ng/ml; AUC0-72 (mean, CI): 1,040 (530-1,678) ng·h/mL; tmax (median, min., and max.); 4.50 (2.50-5.50)] and albendazole [Cmax (mean, CI): 22.27 (1.89-111.78) ng/ ml; AUC0-72 (mean, CI): 94.65 (11.65-507.78) ng·h/mL; tmax (median, min., and max.): 2.50 (1.00-12.00) h]. The 90% confidence interval of the geometric mean ratios demonstrated the bioequivalence in the case of ivermectin (Cmax: 110.68%-120.49%; AUC0-72: 110.46%-119.60%) but not in the case of albendazole (Cmax: 53.10%-70.34%; AUC0-72: 61.13%-76.54%). The pharmacokinetic profile of a new fixed-dose combination of ivermectin and albendazole was characterized. The bioequivalence versus the reference ivermectin was demonstrated, though bioequivalence versus albendazole was not shown. The three medications analyzed were well tolerated. The results allow the advancement to the next phase of the clinical program to demonstrate efficacy and safety in patients affected by soil-transmitted helminths. [ABSTRACT FROM AUTHOR]

New pest management solutions are needed to control soil invertebrates (insects, nematodes, mollusks) in order to implement the goals of the European Green Deal. Natural volatile organic compounds (VOCs) such as 1-octen-3-ol and 3-octanone, emitted by the entomopathogenic fungus Metarhizium brunneum could be part of the solution. Three major crop pests, Agriotes lineatus (wireworm), Diabrotica virgifera virgifera (corn rootworm) and Phyllopertha horticola (garden chafer), were susceptible to fumigation with 1-octen-3-ol and 3-octanone. The toxicity of the VOCs was tested in soil-free arenas and in soils which differed in moisture content and porosity. The mortality rates were dependent on the interaction between the VOC treatment, dose and pest species. The insects differed in their sensitivity to these VOCs. A dose of 1.25 µl of 1-octen-3-ol applied in a closed glass tube was sufficient to kill D. v. virgifera and P. horticola in soil trials whereas 5 µl was needed to kill A. lineatus. The highest dose (20 µl) was highly toxic to all insects. Soil moisture content slightly influenced mortality rates whereas porosity had no obvious impact. The mode of action of the VOCs is unknown but the compounds are likely to cause tissue damage and loss of body fluids. This may explain the shrivelled appearance of corn rootworm and garden chafer and melanisation in wireworm. Both 1-octen-3-ol and 3-octanone show promise as biofumigants. [ABSTRACT FROM AUTHOR]

Simple Summary: Fumigation is the most effective method for the control of Curculio sikkimensis in chestnuts. The effects of ethyl formate (EF) as a fumigant were investigated to evaluate its potential for practical use by farmers. A dose of 180.0 g/m3 and 12 h of fumigation resulted in 100% mortality on a small scale (2 m3). The results of these experiments indicate that EF could be conveniently used as a fumigant by farmers. Castanea crenata Siebold & Zucc. (Fagales: Fagaceae), a species of chestnut native to Korea and Japan, is distributed in Korea, Japan, and northeastern China, where chestnuts are a major economic agroforest product. Curculio spp. is among the main known pests of chestnuts around the world. In Korea, only phosphine (PH3) is permitted for the fumigation of C. sikkimensis larva-infested chestnuts. However, it is applied for large-scale fumigation, and its use is restricted. Moreover, it requires a long exposure time and an application device; thus, it cannot be used by small-scale farmers. In this study, the activity of ethyl formate (EF) as a fumigant against Curculio sikkimensis in chestnuts was investigated, and its potential for practical use by farmers was evaluated. The sorption of EF according to the filling ratio (FR) and fumigation time was tested, and the results revealed that 2.5% FR was the most effective. For C. sikkimensis in chestnuts, the mortality rate increased proportionately with the dose of EF. After exposure to 160 g/m3 of EF in a 12 L desiccator, the adult C. sikkimensis showed 100% mortality. According to the time–dose mortality data collected over 12 h of fumigation, the LCT90 and LCT99 values were estimated as 1052.0 and 1952.0 g·h/m3. The results revealed that immersion was not an effective method for controlling C. sikkimensis. According to the LCT values, a dose of 180.0 g/m3 and 12 h of fumigation resulted in 100% mortality on a small scale (2 m3). The results of this experiment indicate that EF could be conveniently used as a fumigant by farmers. [ABSTRACT FROM AUTHOR]

One of the biggest worries for farmers is the spread of pathogens through the soil. These diseases are difficult to control because they are often tiny in size, buried in the soil, and frequently highly harmful even in small numbers. The Montreal Protocol on Substances that Deplete the Ozone Layer, to which the majority of countries are signatories, has restricted the use of residual pesticides for the management of soil-borne infections, and the demand for food that is free of blemishes is rising. However, it has become urgently necessary to find suitable substitutes as a result of the phase-out of methyl bromide, a significant chemical. After introducing plants that contain glucosinolate, which is digested to produce isothiocyanates (ITC) in the soil, biofumigation has emerged as a crucial procedure to control plant diseases. The existence of glucosinolates and the byproducts of their hydrolysis in soil illustrate the effectiveness and environmental impact of biofumigation. The most significant producers of bioactive chemicals are Brassica species, which makes them suitable for biofumigation applications. This review focuses on the concept, the effective application of biofumigants against soil-borne diseases, and offers several case examples to highlight upcoming difficulties for the concept's continued advancement. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Apple replant disease (ARD) negatively affects plant growth and reduces yields in replanted orchards. In this study, biochar and humic acid were applied to apple replant soil. We aimed to investigate whether biochar and humic acid could promote plant growth and alleviate apple replant disease by reducing the growth of harmful soil microorganisms, changing soil microbial community structure, and improving the soil environment. This experiment included five treatments: apple replant soil (CK), apple replant soil with methyl bromide fumigation (FM), replant soil with biochar addition (2 %), replant soil with humic acid addition (1.5 ‰), and replant soil with biochar combined with humic acid. Seedling biomass, the activity of antioxidant enzymes in the leaves and roots, and soil environmental variables were measured. Microbial community composition and structure were analyzed using ITS gene sequencing. Biochar and humic acid significantly reduced the abundance of Fusarium and promoted the recovery of replant soil microbial communities. Biochar and humic acid also increased the soil enzymes activity (urease, invertase, neutral phosphatase, and catalase), the plant height, fresh weight, dry weight, the activity of antioxidant enzymes (superoxide dismutase, peroxidase, and catalase), and root indexes of apple seedlings increased in replant soil. In sum, We can use biochar combined with humic acid to alleviate apple replant disease. • Biochar and humic acid could reduce Fusarium which causes the apple replant disease (ARD). • T application obviously increased soil microbial diversity and richness, and regulated fungal community structure in replant soil. • The addition of biochar and humic acid significantly increased the apple seedlings growth and alleviate the ARD. [ABSTRACT FROM AUTHOR]

The use of beneficial microorganisms and polysaccharides for the biocontrol of plant diseases currently represents a promising tool for the management of soil-borne pathogens. Despite advancements, enhancing the efficacy and sustainability of these biocontrol methods, particularly in complex soil environments, remains a challenge. Thus, we investigated the potential of four PGPR strains encapsulated in natural alginate extracted from a brown seaweed Bifurcaria bifurcata to evaluate its biocontrol capacities against Verticillium wilt of tomato, ensuring optimal performance through a synergistic effect and innovative bacterial release. Our research demonstrated that the application of PGPR and alginate reduced disease severity and mortality rate and increased the natural defenses of tomato. Results showed that supplying alginate or the PGPR consortium at the root level s stimulates phenylalanine ammonia-lyase activity (the key enzyme of the phenylpropanoid metabolism) and the accumulation of phenolic compounds and lignin in leaves and roots. Treatment with PGPR encapsulated in alginate beads showed the best biocontrol efficiency and was accompanied by a synergistic effect reflecting a rapid, intense, and systemic induction of defense mechanisms known for their effectiveness in inducing resistance in tomato. These promising results suggest that such bioformulations could lead to innovative agricultural practices for sustainable plant protection against pathogens. • Pretreatment of plants with alginate or PGPR reduced Verticillium wilt. • The encapsulation of PGPR in alginate reflected a synergistic effect. • The disease suppression is associated with the inhibition of the pathogen growth. • Disease suppression is associated with the stimulation of natural defenses of the host plant. [ABSTRACT FROM AUTHOR]

[Display omitted] • DFT study for B 3 O 3 quantum dot as a sensor for methyl halides. • Methyl halides@B 3 O 3 complexes are thermodynamically stabile. • NCI analysis confirmed non-covalent interactions. • NBO analysis confirmed charge transfer from the methyl halides towards B 3 O 3 quantum dot. In this study, B 3 O 3 quantum dot has been used for sensing of various methyl halides for the first time. The suitable cavity of B 3 O 3 makes it more suitable for the sensing of variety of analytes. The three, very simple and most important methyl halides (CH 3 F, CH 3 Cl and CH 3 Br) are selected to adsorb on B 3 O 3 surface. Density functional theory (DFT) method with appropriate basis set was implemented. Among the considered complexes, methyl bromide complex CH 3 Br@B 3 O 3) showed higher interaction energy of −16.90 kcal mol−1. The noncovalent interaction (NCI) analysis identified the existence of van der Waals interactions among all analytes and adsorbent. The density of state (DOS) and natural bond orbital (NBO) charges analyses identified the charge transfer and conductive properties of B 3 O 3 nanosheet after interaction with alkyl halides. Frontier molecular orbital study revealed the electronic attributes of considered complexes. It is revealed that B 3 O 3 quantum dot can be a very good choice for sensing of methyl halides and could be helpful for monitoring and reducing the environmental pollution. [ABSTRACT FROM AUTHOR]

The objective of study was to investigate the underlying mechanisms responsible for the ability of 2-Ethylhexylglycidylether (EHGE) fumigation to inhibit the yellowing and senescence of harvested broccoli. We conducted a combination of transcriptomic, metabolomic, physiological, and biochemical analyses of EHGE-fumigated broccoli stored at 20 °C and 90 % relative humidity for five days and compared it to an untreated control. Results indicated that the EHGE treatment inhibited fresh weight loss and the loss of vitamin C, inhibited the reduction in total phenolics, delayed yellowing, as well as the reduction in antioxidant capacity. The data suggest a dual mechanism involving the enhancement of chlorophyll synthesis and the inhibition of chlorophyll degradation is involved. The EHGE treatment also suppressed carotenoid accumulation while promoting the accumulation of flavonoids, resulting in increased antioxidant capacity. However, the specific mechanisms associated with the antioxidant capacity of flavonoids require further study. In summary, the study provides a comprehensive theoretical framework for understanding how EHGE fumigation effectively delays the postharvest senescence of postharvest broccoli. • This paper first studied the effect of 2-Ethylhexylglycidylether (EHGE) on the postharvest preservation of broccoli. • EHGE treatment extends the green coloring of broccoli. • EHGE treatment delays the rate of chlorophyll degradation in broccoli. • EHGE treatment regulates the biosynthesis and metabolism of chlorophyll, carotenoids, and flavonoids in broccoli. [ABSTRACT FROM AUTHOR]

The development of intelligently released and environmentally safe nanocarriers not only aligns with the sustainable agricultural strategy but also offers a potential solution for controlling severe soil-borne bacterial diseases. Herein, the core-shell structured nanocarrier loaded with honokiol bactericide (honokiol@ZnO-ZIF-8) was synthesized via a one-pot method for the targeted control of Ralstonia solanacearum , the causative agent of tobacco bacterial wilt disease. Results indicated that honokiol@ZnO-ZIF-8 nanoparticles induced bacterial cell membrane and DNA damage through the production of excessive reactive oxygen species (ROS), thereby reducing bacterial cell viability and ultimately leading to bacterial death. Additionally, the dissociation mechanism of the nanocarriers was elucidated for the first time through thermodynamic computational simulation. The nanocarriers dissociate primarily due to H+ attacking the N atom on imidazole, causing the rupture of the Zn-N bond under acidic conditions and at room temperature. Furthermore, honokiol@ZnO-ZIF-8 exhibited potent inhibitory effects against other prominent Solanaceae pathogenic bacteria (Pseudomonas syringae pv. tabaci), demonstrating its broad-spectrum antibacterial activity. Biosafety assessment results indicated that honokiol@ZnO-ZIF-8 exhibited non-phytotoxicity towards tobacco and tomato plants, with its predominant accumulation in the roots and no translocation to aboveground tissues within a short period. This study provides potential application value for the intelligent release of green pesticides. The indiscriminate use of agrochemicals poses a significant threat to environmental, ecological security, and sustainable development. Slow-release pesticides offer a green and durable strategy for crop disease control. In this study, we developed a non-phytotoxic and pH-responsive honokiol@ZnO-ZIF-8 nano-bactericide based on the pathogenesis of Ralstonia solanacearum. Thermodynamic simulation revealed the dissociation mechanism of ZIF-8, with different acidity controlling the dissociation rate. This provides a theoretical basis for on-demand pesticide release while reducing residue in the. Our findings provide strong evidence for effective soil-borne bacterial disease control and on-demand pesticide release. [Display omitted] • A porous ZIF-8 carrier was prepared for bactericide delivery. • Honokiol-loaded carrier (Honokiol@ZnO-ZIF-8) exhibited pH-responsive release properties. • ZnO-ZIF-8 and honokiol exhibited synergistic bactericidal effect. • Thermodynamics simulation revealed the cracking process of the ZIF-8 cage. • Honokiol@ZnO-ZIF-8 conforms to the concept of green bactericide. [ABSTRACT FROM AUTHOR]

• We conducted an analysis on the branch dependence of N2-brodened halfwidths of CH3Br lines. • The methods consider the k-degeneracy of symmetric-top molecular lines. • The RRB with LM method addresses both line coupling and line mixing effects. • The RRB with LM method yields a very good agreement with measurements at temperatures of 296 K. The N 2 -broadened halfwidths of CH 3 Br in the ν 6 band have been calculated, along with the relaxation matrices W. These calculations employ our modified and refined versions of the Robert-Bonamy formalism. Extensive comparisons between the predicted halfwidths from the models and experimental measurements at T = 296 K are presented. Our latest model very closely matches the measurements. Meanwhile, we considered line mixing effects in the spectral profile of the RQ(j,0) sub-branch. Our method probably yields too large values of the off-diagonal elements of W. Finally, by comparing our calculated halfwidths with the data in HITRAN, we have observed generally good agreement, especially for lines with high values of j. However, the agreement becomes poor for lines with low values of j, deteriorating as j decreases. We identified a factor contributing to this poor agreement: the neglect of branch dependence in the development of HITRAN data. We believe that for lines with low values of j, this oversight undermines the reliability of the halfwidth values of CH 3 Br in HITRAN. [ABSTRACT FROM AUTHOR]

Exotic ants and termites, including Solenopsis invicta, are frequent hitchhikers intercepted from miscellaneous nonfood commodities. In particular, S. invicta has been intercepted in Korea in imported nursery plants, stone, and lumber products, which increases the potential for establishment of this destructive invasive pest in Korea. In this study, we conducted commercial-scale fumigation trials to evaluate ethyl formate (EF) as a potential alternative of methyl bromide using two species of imported rubber plants and pieces of marble as representative good and workers of Reticulitermes speratus as an EF-resistant surrogate for S. invicta. An EF treatment at 35 g/m3 for 4 h at >15 °C, the dose required for LCt99% (lethal concentration × time product required for 99% mortality of R. speratus), resulted in the complete control of R. speratus workers tested with rubber plants (Ficus benghalensis and F. retusa) and marble, 9% (w/v) and 60% (v/v) loading ratios, respectively. EF treatment did not adversely affect the leaf chlorophyll content, leaf color, and overall health of rubber plants or the visual appearance of the marble. Our results suggest that EF fumigation is a potential alternative to methyl bromide for the disinfestation of hitchhiking invasive termites and ants, including S. invicta, on imported rubber plants and stone products. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ongoing use of 1080 toxin for the control of mammal pests in New Zealand remains highly contentious. Several reviews over the last 25 years identified information gaps and areas of concern, both social and scientific. In this paper these areas of concern are discussed and the extensive scientific and social research that has been undertaken to clarify and address them is reviewed. Although there has been a major national investment in research aimed at finding an alternative to 1080, that has not yet been fully achieved because of low or inconsistent efficacy and/or low cost-effectiveness of alternatives, regulatory difficulties in obtaining approval for aerial delivery of any alternative, and toxic residue concerns. Finding an alternative that has similar efficacy while satisfying the demands for species-selectivity, no residues, and humaneness is a continuing challenge. The most promising prospect appears to be through understanding the genome of the target animals and opportunities for genetic manipulation, either by developing species-specific designer lethal toxicants based on genome mining, or by gene editing to develop non-lethal technologies. Both will require considerable time and funding for research, and considerable effort and engagement to address social and regulatory hurdles. [ABSTRACT FROM AUTHOR]

Rapid transport by deep convection is an important mechanism for delivering surface emissions of reactive halocarbons and other trace species to the tropical tropopause layer (TTL), a key region of transport to the stratosphere. Recent model studies have indicated that increased delivery of short-lived halocarbons to the TTL could delay stratospheric ozone recovery. We report here measurements in the TTL over the western Pacific Ocean of short-lived halocarbons and other trace gases that were transported eastward after convective lofting over Asia. Back-trajectories indicate the sampled air primarily originated from the Indian subcontinent. While short-lived organic bromine species show no measurable change over background mixing ratios, short-lived chlorinated organic species were elevated above background mixing ratios (dichloromethane (Δ48.2 ppt), 1,2-dichloroethane (Δ4.21 ppt), and chloroform (Δ4.85 ppt)), as well as longer-lived halogenated species, methyl chloride (Δ82.0 ppt) and methyl bromide (Δ1.91 ppt). This transported air mass thus contributed an excess equivalent effective chlorine burden of 316 ppt, with 119 ppt from short lived chlorinated species, to the TTL. Non-methane hydrocarbons (NMHC) were elevated 60 - 400% above background mixing ratios. The NMHC measurements were used to characterize the potential source regions, which are consistent with the convective influence analysis. The measurements indicate a chemical composition heavily impacted by biofuel/biomass burning and industrial emissions. This work shows that convection can loft Asian emissions, including short-lived chlorocarbons, and transport them to the remote TTL. [ABSTRACT FROM AUTHOR]

In the present study, ten monoterpenes and phenylpropenes were tested for their contact and fumigant toxicities against oleander aphid, Aphis nerii (Hemiptera: Aphididae). Also, the inhibitory effect of compounds on acetylcholinesterase (AChE) and adenosine triphosphatases (ATPases) activities was assessed in vitro to explore their possible modes of action. (-)-Menthol and (+)-camphor were the most potent contact toxicants among the tested compounds against A. nerii third nymphal instar with LC50 values of 0.06 and 0.08 mg/L, respectively. In contrary, 1,8-cineole, p-cymene and α-pinene showed a weak or no contact toxicity where their LC50 values were >10 mg/L. In fumigation assay, cuminaldehyde (LC50 = 3.10 µl/L), (+)-camphor (LC50 = 3.57 µl/L) and (-)-menthol (LC50 = 3.59 µl/L) showed the highest toxicity against A. nerii, while eugenol (LC50 >50 µl/L) was the less effective compound. (−)-Citronellal (IC50 = 2.22 mM) and trans-cinnamaldehyde (IC50 = 1.12 mM) caused the highest inhibitory effect on AChE and ATPases activity, respectively. In general, all compounds showed strong inhibitory effect on the activity of ATPases than AChE. [ABSTRACT FROM AUTHOR]

Alfalfa hay that was grown on a field treated with a methyl bromide and chloropicrin pesticide (at a 98/2 weight ratio) resulted in animal sickness, posing a disposal issue for the harvested feed. In consideration of disposal options, emissions and residues from burning treated and untreated alfalfa hay were sampled and analyzed to provide data for an assessment of potential health and environmental effects. Treated alfalfa hay was tested in parallel with untreated alfalfa in a controlled laboratory combustion facility. Results showed that about half of the bromine and chlorine in the treated hay was emitted and the remaining was retained in the ash. The alfalfa hay burned poorly, with modified combustion efficiencies, the ratio of CO2 to CO + CO2, below 0.89. The emission factor for PM2.5 was statistically higher for the untreated versus treated alfalfa but the PAHs were doubled in the treated alfalfa. The treated alfalfa had significantly more emissions of polychorinated dibenzodioxin/dibenzofuran than the untreated alfalfa by a factor of 10, but less polybrominated dibenzodioxin/dibenzofuran. The high Br concentration in the treated alfalfa biomass may have resulted in formation and emission of mixed halogen compounds which were unable to be analyzed for lack of standards. Comparison of volatile organic compound emissions were unremarkable with the exception of MeBr where emissions from the treated alfalfa were over 300 times higher than the untreated biomass. The potential complications due to emissions and permitting of an open burn or contained incinerator left options for landfilling and feedstock blending for handling the treated alfalfa. Implications: This paper illustrates the issues agricultural managers must deal with concerning the combustive disposal of contaminated crops. A method is presented whereby combustion of contaminated crops can be assessed for their suitability for disposal by open air or enclosed burning. [ABSTRACT FROM AUTHOR]

In this study, the volatilomes of naturally growing plant leaves were immobilized in a suitable substrate to enhance vapors' diffusion in the soil to eradicate the Fusarium wilt pathogens in Tomato. Volatilomes produced by Mentha spicata leaves immobilized in vermiculite ball was found to be effective and exhibit 92.35 percent inhibition on the mycelial growth of Fusarium oxysporum f. sp. lycopersici (FOL). Moreover, the volatilomes of M. spicata immobilized vermiculite balls were tested based on the distance traveled by the diffused volatilomes from the ball and revealed that the volatilomes of M. spicata traveled up to 20 cm distance from the center of PVC (Polyvinly chloride) chamber showed maximum reduction in colony growth of FOL at 12th day after inoculation. Tomato plants inoculated with FOL revealed increased expressions of defense gene, pathogenesis related protein (PR1) with 2.63-fold after 72 h and the gene, transcription factor (WRKY) increased with 2.5-fold after 48 h on exposure to the volatilomes of M. spicata vermiculite balls. To the best of our knowledge, this is the first report on development of volatilomes based vermiculite ball formulations. This result indicated that the volatilomes of M. spicata are promising phyto-fumigants for management of Tomato Fusarial wilt. [ABSTRACT FROM AUTHOR]

Soil disinfestation with steam has been evaluated in strawberry fruiting fields as a nonchemical method of soil disinfestation; however, little is known about the use of steam for field production of strawberry daughter plants. The objective of this study was to compare daughter plant production in soils previously treated with steam compared to those treated with standard methyl bromide (MB) and chloropicrin (Pic) treatments. A prototype field steam applicator and a self-propelled dieselfueled steam generator and applicator were tested at two high-elevation nurseries near Macdoel, CA, in Sept. 2018 and Aug. 2020, respectively. The steam application heated the soil above 60 °C for ~60 minutes to a depth of 25 cm at both nurseries. The pest control efficacy of the steam applications against weeds, Verticillium spp., Tylenchulus semipenetrans, and Pythium ultimum were similar to that of MB:Pic. The stolons and daughter plants densities in fields with steam treatment were similar to those in fields with MB:Pic treatment. Therefore, we suggest that soil disinfestation with steam may be a viable method of producing healthy strawberry plants. However, more research is needed to verify plant sanitation and quality. [ABSTRACT FROM AUTHOR]

With' Kyoho' grapes as the expeêmental mateiai, the effects of different concentrations of chlorine dioXdc (5, 10 and 15 mg/L) and ozone (30, 60 and 90 mg/m3) fumigation on the contents of tote phenols, proanthocyanidins and malondialdehyde (MDA) and the activity of polyphenol oXdase (PPO), peroxidase (POD), catOase (CAT) and superoxiVc dismutase (SOD) in the grapes during low temperature storage were compared and analyzed, hoping te proide refer-encc for the storage and preservation of' Kyoho' grapes after harvest. The results showed tUat compared with the controt, certain concentrations of fuminant presera-atives inhibited the deeradation of totO phenots and proanthocyaninins in' Kyoho' grapes te varying deerees, maintained better celt membrane integrity, and inhibited the increase of MDA content and PPO activity, and in the later stage, more stable POD and higher activity of CAT and SOD were maintained. Comprehensive analysis showed Oiat among the sin fumigation treatments, 10 mg/L CKO and 60 mg/m3 O3 could delay the aging process of grapes and maintain better antioXVant capacity and storage quality. [ABSTRACT FROM AUTHOR]

Rice weevil Sitophilus oryzae (L.) is one of most serious insect pests of stored grains. Management of this is thus vital and fumigation with phosphine gas is the most common method. However, overreliance on this has resulted in the development of heritable resistance in S. oryzae. The detection of frequency and distribution of phosphine resistance is crucial for the development of resistance management strategy. This study assesses the frequency, strength and distribution of phosphine resistance in S. oryzae populations from four southern states of India viz., Tamil Nadu, Kerala, Andhra Pradesh and Telangana. The bioassay results revealed that all these survived at both the discriminating concentrations of 0.04 and 0.25 mg/l. There were no susceptible and weak resistant populations, and exhibited varied frequency of strong resistance ranging from 13.33 to 80.90%. The populations from Pudukottai (80.90%) recorded high frequency of strong resistance followed by Trichy (68.97%) and Tirunelveli (67.82%) ones; the one from Thiruvarur exhibited lowest (13.33%). The results indicated that the resistance to phosphine in S. oryzae was common and prevalence of strong resistant individuals was prevalent across the sampled regions. [ABSTRACT FROM AUTHOR]

Strawberry runners (transplants) in many regions of the world are produced in soils treated with chemical fumigants to control pathogens and weeds and meet phytosanitary requirements. Many fumigants, however, are under threat of withdrawal because of concerns over their impact on the environment (e.g., methyl bromide). The current study considered the use of microwaves for heat disinfestation of soil for field-grown runners for the first time. Results from two field experiments showed that microwave treatment reduced the survival of buried inoculum of the strawberry pathogens Fusarium oxysporum (by up to 93%) and Sclerotium rolfsii (by up to 100%) compared with untreated soil. Furthermore, the treatment reduced the subsequent growth of these pathogens in the laboratory by up to 82% and 100%, respectively. Microwave treatment also reduced the natural DNA concentration of Pythium spp. (clades I & F) in soil by up to 94% compared with untreated soil. The effect of microwave against soilborne pathogens reduced as soil depth increased. Microwave treatment reduced the emergence of weeds in field soils by up to 65% and increased runner yields by 10–37%. The effect of microwave treatment on runner yield was greater when all soil was treated, rather than when strips of soil around the mother plants were treated. Results from complimentary pot experiments showed that early strawberry growth in the glasshouse was equivalent in soils treated with microwave or the fumigant methyl bromide/chloropicrin. Furthermore, the early performance of runners sourced from field soils treated with microwave or methyl bromide/chloropicrin was equivalent. Results from the pot experiments also showed that steam treatment required 10 times more energy per mass of soil to disinfest than microwave. The limitations of microwave in the current experiments are discussed, but the capacity for the technology to disinfest field soils in an energy-efficient manner demonstrates its potential for further development as an alternative to soil disinfestation with chemical fumigants. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) (PLA) nanofibres containing different proportions of the essential oils from Ocimum basilicum L. and Ocimum gratissimum L. were prepared by solution blow spinning method. The essential oils were extracted by hydrodistillation and characterized by gas chromatography. MEV, contact angle, DSC and FTIR were used to characterize the nanofibres. The effect of bioative nanofibres on the growth of the fungus and on the production of ochratoxin A were evaluated using the fumigation test. Linalool, 1·8‐cineole and camphor were the principal components of the essential oil from O. basilicum, and eugenol was the principal constituent in the oil from O. gratissimum. An increase in the average diameter of the nanofibres was observed with the addition of the essential oils. The essential oils acted as a plasticizer, resulting in a reduction in the crystallinity of the PLA. The encapsulation of essential oils in PLA nanofibres was verified by FTIR. An effective antifungal and antimicotoxygenic activity against Aspergillus ochraceus and Aspergillus westerdjikiae was observed for the bioative nanofibres. These results confirm the potential of PLA nanofibres containing the essential oils for the control of toxigenic fungi that cause the deterioration of food and are harmful to human health. [ABSTRACT FROM AUTHOR]

Methyl bromide (CH3Br) is a potent ozone-depleting substance (ODS) that has both natural and anthropogenic sources. CH3Br has been used mainly for preplant soil fumigation, post-harvest grain and timber fumigation, and structural fumigation. Most non-quarantine and pre-shipment (non-QPS) uses were phased out by 2005 for non-Article 5 (developed) countries and by 2015 for Article 5 (developing) countries under the Montreal Protocol on Substances that Deplete the Ozone Layer; some uses have continued under critical-use exemptions (CUEs). Under the protocol, individual nations are required to report annual data on CH3Br production and consumption for quarantine–pre-shipment (QPS) uses, non-QPS uses, and CUEs to the United Nations Environment Programme (UNEP). In this study, we analyzed high-precision, in situ measurements of atmospheric mole fractions of CH3Br obtained at the Gosan station on Jeju Island, South Korea, from 2008 to 2019. The background mole fractions of CH3Br in the atmosphere at Gosan declined from 8.5±0.8 ppt (parts per trillion) in 2008 to 7.4±0.6 ppt in 2019 at a rate of -0.13±0.02 ppt yr -1. At Gosan, we also observed periods of persistent mole fractions (pollution events) elevated above the decreasing background in continental air masses from China. Statistical back-trajectory analyses showed that these pollution events are predominantly traced back to CH3Br emissions from eastern China. Using an interspecies correlation (ISC) method with the reference trace species CFC-11 (CCl3F), we estimate anthropogenic CH3Br emissions from eastern China at an average of 4.1±1.3 Gg yr -1 in 2008–2019, approximately 2.9±1.3 Gg yr -1 higher than the bottom-up emission estimates reported to UNEP. Possible non-fumigation CH3Br sources – rapeseed production and biomass burning – were assessed, and it was found that the discrepancy is most likely due to unreported or incorrectly reported QPS and non-QPS fumigation uses. These unreported anthropogenic emissions of CH3Br are confined to eastern China and account for 30 %–40 % of anthropogenic global CH3Br emissions. They are likely due to delays in the introduction of CH3Br alternatives, such as sulfuryl fluoride (SO2F2), heat, and irradiation, and a possible lack of industry awareness of the need for regulation of CH3Br production and use. [ABSTRACT FROM AUTHOR]

Modified atmospheres (MAs) are safe and environmentally friendly pest control alternatives for protecting stored products; however, longer exposure times are required than those required for toxic gas fumigation. To reduce MA exposure time, CO2 could be used in combination with phosphine, which could also reduce insect resistance to phosphine. In the present study, therefore, various concentrations of CO2 and half the recommended dose of phosphine (0.5 mg/L) were assessed separately and in combination against Oryzaephilus surinamensis and Tribolium confusum adults. In addition, the effects on some of the chemical properties of dates were determined. The mortality rate of O. surinamensis and T. confusum increased as either the exposure period or concentration increased. At 85 % CO2, 36 h exposure was more enough to reach 100 % mortality. In addition, the phosphine dose combined with the lowest concentration of CO2 caused 100% mortality after 6 h. All estimated chemical compositions were significantly different in treated date fruits compared with those in control fruits. Specifically, all treatments reduced free phenol content (0.11- 0.29 mg/g) in date fruits compared with the control (0.31 mg/g). All treatments increased total sugar and reducing sugar content in dates, with the highest concentrations recorded when 85% CO2 was combined with the phosphine dose. Therefore, a combination of MAs and half the recommended dose of phosphine could help control insects on stored dried dates with short treatment durations, with the added value of achieving some positive effects on fruit quality. [ABSTRACT FROM AUTHOR]

Phalaris minor is a major weed of wheat crop which has evolved resistance against herbicides. Isoproturon is the most accepted herbicide developed resistance in 1992. Later, introduced herbicides also developed resistance and cross-resistance to their respective binding sites. Isoproturon binds at the QB binding site of the D1 protein of photosystem-II (PS-II), which blocks the electron transfer in photosynthesis. In this work, we have carried out a series of computational studies to prioritize the promising herbicides against D1 protein of P. minor. Through the computational studies, twenty-four lead molecules are prioritized which have shown a higher binding affinity and inhibition constant than the reference ligand molecule. The binding and conformational stability of docked complexes was evaluated by molecular dynamics simulations and binding free energy calculations i.e., MM/PBSA. A list of amino acids such as Ala225, Ser226, Phe227, and Asn229 present in the binding site of protein is obtained to be playing an important role in the stability of the protein-lead complex via hydrogen bond and π-π interactions. Binding free energy calculation revealed that the selected lead molecule binding is energetically favorable and driven by electrostatic interactions. Among 24 leads, computational results have uncovered eight promising compounds as potential herbicides which have shown comparable physiochemical profile, better docking scores, system stability, H-bond occupancy, and binding free energy than terbutryn, a reference molecule. These prioritized molecules were custom synthesized and evaluated for their herbicidal activity and specificity through whole plant assay under laboratory-controlled conditions. The lead molecule ELC5 (6-ethoxy-4-N-(2-morpholin-4-ylethyl)-2-N-propan-2-yl-1,3,5-triazine-2,4-diamine) has shown comparable activity to the reference herbicide(isoproturon) against P. minor. [ABSTRACT FROM AUTHOR]

The ham mite, Tyrophagus putrescentiae (Schrank) (Sarcoptiformes: Acaridae), is a common pest infesting several stored products, particularly the aged hams. In this study, we reported the efficacy of nitric oxide (NO) fumigation, a recently discovered fumigation treatment under the ultra-low oxygen environment, at various concentrations and time under the laboratory conditions at 25°C against different mite stages on both dietary media and ham meat. Our results showed that NO fumigation was effective against all mite stages and 100% control was achieved. Generally, the egg was the most tolerant stage and required 48-, 24-, 16-, and 8-h treatments to achieve 100% mortality at 0.5, 1, 1.5, and 2% NO concentration on dietary media, respectively. Tyrophagus putrescentiae mobile immatures and adult stages were less tolerant, and 100% mortality was achieved after 16-, 8-, 8-, and 4-h treatment at 0.5, 1, 1.5, and 2% NO, respectively. The median lethal concentration (LC50) of NO on egg was 0.86, 0.68, and 0.32% for 8-, 16-, and 24-h treatments. In addition, a confirmatory test was conducted on ham meat at 0.5 and 1.0% of NO and similar efficacy was found. Complete control of egg was achieved after 48- and 24-h treatment at 0.5 and 1.0% of NO, respectively, and larvae and adult mites were 100% controlled after 16 and 8 h at 0.5 and 1.0% of NO, respectively. Our results demonstrated that NO fumigation was effective against T. putrescentiae and can be a potential alternative treatment to methyl bromide for cured-ham pest control. [ABSTRACT FROM AUTHOR]

Methyl bromide (MB) is a fumigant that has been widely for killing pests on plants in trade, soils, and structures used as well as for fumigating post-harvest commodities, such as wheat and cereals, nuts, spices, dried, tobacco and fresh fruits. Methyl bromide depletes the ozone layer and it must be replaced so the United States, along with other countries, has phased out production of methyl bromide with important exceptions for critical uses as well as quarantine and pre-shipment. The aim of this study is to evaluate the effect of methyl bromide on some male reproductive hormones among workers in dates stores. About 30 healthy men aged (25-47 years) were selected for comparison with workers aged (25-47) who were exposed to methyl bromide through gas inhalation or dermal absorption. Results shows that the mean age of the participants was 32.62 ± 7.45 years. The analysis revealed statistically significant differences in the assay of reproductive hormones, where there was a significant increase (P < 0.01) for both the FSH and LH hormone and a high significant decrease(P < 0.01) for the testosterone hormone among the workers in the stores of dates compared to the control. The result described in this study showed significant differences of the level of FSH and testosterone for smoking and non smoking workers. IncConclusion the results suggest that chronic exposure related to methyl bromide dose may reduce potential male reproductivity. [ABSTRACT FROM AUTHOR]