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PloS One 2024In the present study, we attempted to use melatonin combined with germination treatment to remove pesticide residues from contaminated grains. High levels of pesticide...
In the present study, we attempted to use melatonin combined with germination treatment to remove pesticide residues from contaminated grains. High levels of pesticide residues were detected in soybean seeds after soaking with chlorothalonil (10 mM) and malathion (1 mM) for 2 hours. Treatment with 50 μM melatonin for 5 days completely removed the pesticide residues, while in the control group, only 61-71% of pesticide residues were removed from soybean sprouts. Compared with the control, melatonin treatment for 7 days further increased the content of ascorbic acid (by 48-66%), total phenolics (by 52-68%), isoflavones (by 22-34%), the total antioxidant capacity (by 37-40%), and the accumulated levels of unsaturated fatty acids (C18:1, C18:2, and C18:3) (by 17-30%) in soybean sprouts. Moreover, melatonin treatment further increased the accumulation of ten components of phenols and isoflavones in soybean sprouts relative to those in the control. The ability of melatonin to accelerate the degradation of pesticide residues and promote the accumulation of antioxidant metabolites might be related to its ability to trigger the glutathione detoxification system in soybean sprouts. Melatonin promoted glutathione synthesis (by 49-139%) and elevated the activities of glutathione-S-transferase (by 24-78%) and glutathione reductase (by 38-61%). In summary, we report a new method in which combined treatment by melatonin and germination rapidly degrades pesticide residues in contaminated grains and improves the nutritional quality of food.
Topics: Melatonin; Germination; Pesticide Residues; Seeds; Glycine max; Nutritive Value; Antioxidants; Edible Grain; Phenols; Food Contamination; Glutathione
PubMed: 38713652
DOI: 10.1371/journal.pone.0303040 -
Pesticide Biochemistry and Physiology May 2024White mustard, (Sinapis alba), a problematic broadleaf weed in many Mediterranean countries in arable fields has been detected as resistant to tribenuron-methyl in...
White mustard, (Sinapis alba), a problematic broadleaf weed in many Mediterranean countries in arable fields has been detected as resistant to tribenuron-methyl in Tunisia. Greenhouse and laboratory studies were conducted to characterize Target-Site Resistance (TSR) and the Non-Target Site Resistance (NTSR) mechanisms in two suspected white mustard biotypes. Herbicide dose-response experiments confirmed that the two S. alba biotypes were resistant to four dissimilar acetolactate synthase (ALS)-pinhibiting herbicide chemistries indicating the presence of cross-resistance mechanisms. The highest resistance factor (>144) was attributed to tribenuron-methyl herbicide and both R populations survived up to 64-fold the recommended field dose (18.7 g ai ha). In this study, the metabolism experiments with malathion (a cytochrome P450 inhibitor) showed that malathion reduced resistance to tribenuron-methyl and imazamox in both populations, indicating that P450 may be involved in the resistance. Sequence analysis of the ALS gene detected target site mutations in the two R biotypes, with amino acid substitutions Trp574Leu, the first report for the species, and Pro197Ser. Molecular docking analysis showed that ALS enzyme cannot properly bind to tribenuron-methyl's aromatic ring due to a reduction in the number of hydrogen bonds, while imazamox can still bind. However, Trp574Leu can weaken the binding affinity between the mutated ALS enzyme and both herbicides with the loss of crucial interactions. This investigation provides substantial evidence for the risk of evolving multiple resistance in S. alba to auxin herbicides while deciphering the TSR and NTSR mechanisms conferring cross resistance to ALS inhibitors.
Topics: Acetolactate Synthase; Herbicides; Herbicide Resistance; Sinapis; Malathion; Mutation; Plant Proteins; Arylsulfonates; Molecular Docking Simulation; Imidazoles
PubMed: 38685248
DOI: 10.1016/j.pestbp.2024.105882 -
Malaria Journal Apr 2024Achieving effective control and elimination of malaria in endemic regions necessitates a comprehensive understanding of local mosquito species responsible for malaria...
BACKGROUND
Achieving effective control and elimination of malaria in endemic regions necessitates a comprehensive understanding of local mosquito species responsible for malaria transmission and their susceptibility to insecticides.
METHODS
The study was conducted in the highly malaria prone Ujina Primary Health Center of Nuh (Mewat) district of Haryana state of India. Monthly entomological surveys were carried out for adult mosquito collections via indoor resting collections, light trap collections, and pyrethrum spray collections. Larvae were also collected from different breeding sites prevalent in the region. Insecticide resistance bioassay, vector incrimination, blood meal analysis was done with the collected vector mosquitoes.
RESULTS
A total of 34,974 adult Anopheles mosquitoes were caught during the survey period, out of which Anopheles subpictus was predominant (54.7%). Among vectors, Anopheles stephensi was predominant (15.5%) followed by Anopheles culicifacies (10.1%). The Human Blood Index (HBI) in the case of An. culicifacies and An. stephensi was 6.66 and 9.09, respectively. Vector incrimination results revealed Plasmodium vivax positivity rate of 1.6% for An. culicifacies. Both the vector species were found resistant to DDT, malathion and deltamethrin.
CONCLUSION
The emergence of insecticide resistance in both vector species, compromises the effectiveness of commonly used public health insecticides. Consequently, the implementation of robust insecticide resistance management strategies becomes imperative. To effectively tackle the malaria transmission, a significant shift in vector control strategies is warranted, with careful consideration and adaptation to address specific challenges encountered in malaria elimination efforts.
Topics: Animals; Humans; Insecticides; Insecticide Resistance; Anopheles; Malaria; DDT; Mosquito Control; Mosquito Vectors; Nitriles; Pyrethrins; India
PubMed: 38632650
DOI: 10.1186/s12936-023-04797-8 -
Heliyon Apr 2024Over the past decade, food safety has become a major concern due to the intensive use of pesticides. Pesticide contamination has been observed in poultry products when...
Over the past decade, food safety has become a major concern due to the intensive use of pesticides. Pesticide contamination has been observed in poultry products when seeds are coated with pesticides or when stored products are exposed to pesticides in warehouses. In this experiment, the residue levels of malathion transferred from corn grain to the different parts of the chicken product, its transfer factors (TFs) and the human dietary risk for consumers were evaluated. Growth performance and carcass parameters of the chicken samples were also determined after different doses of malathion exposure. Malathion residues from different parts of chicken meat (breast, thigh, wing, liver and skin) were extracted by the QuEChERS method and analyzed by liquid chromatography-mass spectrophotometry (LC-MS/MS). A deterministic approach was used to calculate the acute and chronic risk assessment. Body weight, feed conversion ratio and feed intake decreased with increasing malathion dose. In addition to reduced feed intake, cold carcass and liver weights of the chicks were also decreased. The highest residues were found in the skin of the chicken followed by the breast, thigh, wing and liver. The TFs of malathion varied between 0.00 and 0.05 according to the different doses applied (4 mg/kg, 8 mg/kg, 16 mg/kg, 32 mg/kg). The chronic exposure assessment (HQ) showed that consumers of all ages and genders consumed 0.008-0.604% of the acceptable daily intake (0.3 mg/kg body weight (bw)/day) of malathion from chicken products. The acute intake assessment (aHQ) of consumers ranged from 0.00015 to 0.0135% of the acute reference dose (0.3 mg/kg bw). In conclusion the results suggest that the risk associated with the malathion residues in chicken meat was found to be low but the residue levels in meat should not be ignored.
PubMed: 38560236
DOI: 10.1016/j.heliyon.2024.e28438 -
Journal of the American Mosquito... Jun 2024Haiti is home to approximately 11 million people and has a high incidence of vector-borne disease, including more than 70,000 cases of dengue per year. Vector control is...
Haiti is home to approximately 11 million people and has a high incidence of vector-borne disease, including more than 70,000 cases of dengue per year. Vector control is difficult in Haiti and adulticide spray of malathion is the main method of control employed during the outbreak of disease although pyrethroids are used in both bed net campaigns and in widely available aerosol cans for personal use. However, limited pathogen or insecticide resistance surveillance data are available for making operational decisions. In this study, we assessed Aedes aegypti from serial surveillance collections from 3 locations for the presence of dengue virus serotypes 1-3 (DENV1-3) by polymerase chain reaction and assessed, by melt curve analysis, samples from 10 locations in 2 departments for the presence of two mutations (V1016I and F1534C), that in combination, are linked to strong pyrethroid insecticide resistance. Only one of the 32 tested pools was positive for the presence of dengue virus. The two knockdown resistance (kdr) mutations were present in all locations. The 1016I mutation frequency varied from 0.29 to 0.91 and was in all sites lower than the 0.58-1.00 frequency of the 1534C mutation. We also observed that the genotype homozygous for both mutations (IICC), which has been linked to strong pyrethroid resistance, varied from 13 to 86% in each population. Notably, 3 locations - Ti Cousin and Christianville in Ouest department and Camp Coq in Nord department had more than 30% of the tested population without the presence of kdr mutations. These results indicate that the kdr markers of pyrethroid resistance are present in Haiti, at high frequency in several locations and, based on previous studies linking kdr genotypes and phenotypic resistance, that operational interventions with pyrethroids are not likely to be as effective as expected.
Topics: Animals; Aedes; Haiti; Insecticide Resistance; Dengue Virus; Dengue; Mutation; Insecticides; Mosquito Vectors; Pyrethrins
PubMed: 38547924
DOI: 10.2987/23-7160 -
Plant Direct Mar 2024Johnsongrass [ (L.) Pers.] is a troublesome weed species in different agricultural and non-agricultural areas. Because of its biology, reproductive system, and seed...
Target-site mutations Ile1781Leu and Ile2041Asn in the gene confer resistance to fluazifop-p-butyl and pinoxaden herbicides in a johnsongrass accession from Arkansas, USA.
Johnsongrass [ (L.) Pers.] is a troublesome weed species in different agricultural and non-agricultural areas. Because of its biology, reproductive system, and seed production, effective management is challenging. An accession with low susceptibility to the acetyl-CoA carboxylase (ACCase)-inhibiting herbicides fluazifop-p-butyl (fluazifop) and pinoxaden was collected in eastern Arkansas. In this research, the molecular mechanisms responsible for ACCase resistance were investigated. Dose-response experiments showed a resistance factor of 181 and 133 for fluazifop and pinoxaden, respectively. Molecular analysis of both and genes was researched. Nucleotide comparison of between resistant and susceptible accessions showed no single nucleotide polymorphisms. Nonetheless, analysis of in fluazifop-resistant johnsongrass plants revealed the Ile1781Leu target-site mutation was dominant (nearly 75%), whereas the majority of pinoxaden-resistant johnsongrass plants had the Ile2041Asn (60%). Not all sequenced johnsongrass plants displayed a target-site mutation, suggesting the presence of additional resistance mechanisms. Amplification of and was not responsible for resistance because of the similar values obtained in both resistant and susceptible accessions. Experiments with malathion and NBD-Cl suggest the presence of herbicide metabolism. Outcomes of this research demonstrated that fluazifop- and pinoxaden-resistant johnsongrass plants displayed a target-site mutation in , but also that non-target-site resistance mechanisms would be involved and require a detailed study.
PubMed: 38516339
DOI: 10.1002/pld3.576 -
Plants (Basel, Switzerland) Feb 2024The spotted-wing drosophila, (Matsumura) (Diptera: Drosophilidae), is a pest that reduces the productivity of small fruits. Entomopathogenic nematodes (EPNs) and...
The spotted-wing drosophila, (Matsumura) (Diptera: Drosophilidae), is a pest that reduces the productivity of small fruits. Entomopathogenic nematodes (EPNs) and chemical insecticides can suppress this pest, but the compatibility of the two approaches together requires further examination. This laboratory study evaluated the compatibility of IBCBn 06, IBCBn 02, IBCBn 24, and HB with ten chemical insecticides registered for managing pupae. In the first study, most insecticides at the recommended rate did not reduce the viability (% of living infective juveniles (IJs)) of and both species. The viability of was lowered by exposure to spinetoram, malathion, abamectin, azadirachtin, deltamethrin, lambda-cyhalothrin, malathion, and spinetoram after 48 h. During infectivity bioassays, phosmet was compatible with all the EPNs, causing minimal changes in infectivity (% pupal mortality) and efficiency relative to EPN-only controls, whereas lambda-cyhalothrin generally reduced infectivity of EPNs on pupae the most, with a 53, 75, 57, and 13% reduction in infectivity efficiency among , and , respectively. The second study compared pupal mortality caused by the two most compatible nematode species and five insecticides in various combinations. Both species caused 78-79% mortality among pupae when used alone, and were tested in combination with spinetoram, malathion, azadirachtin, phosmet, or novaluron at a one-quarter rate. Notably, caused 79% mortality on pupae when used alone, and 89% mortality when combined with spinetoram, showing an additive effect. Novaluron drastically reduced the number of progeny IJs when combined with by 270 IJs and by 218. Any adult flies that emerged from EPN-insecticide-treated pupae had a shorter lifespan than from untreated pupae. The combined use of and compatible chemical insecticides was promising, except for novaluron.
PubMed: 38475479
DOI: 10.3390/plants13050632 -
Evolutionary Applications Feb 2024Molecular mechanisms driving the escalation of pyrethroid resistance in the major malaria mosquitoes of Central Africa remain largely uncharacterized, hindering...
Molecular mechanisms driving the escalation of pyrethroid resistance in the major malaria mosquitoes of Central Africa remain largely uncharacterized, hindering effective management strategies. Here, resistance intensity and the molecular mechanisms driving it were investigated in a population of from northern Cameroon. High levels of pyrethroid and organochloride resistance were observed in population, with no mortality for 1× permethrin; only 11% and 33% mortalities for 5× and 10× permethrin diagnostic concentrations, and <2% mortalities for deltamethrin and DDT, respectively. Moderate bendiocarb resistance (88% mortality) and full susceptibility to malathion were observed. Synergist bioassays with piperonyl butoxide recovered permethrin susceptibility, with mortalities increasing to 53.39%, and 87.30% for 5× and 10× permethrin, respectively, implicating P450 monooxygenases. Synergist bioassays with diethyl maleate (DEM) recovered permethrin and DDT susceptibilities (mortalities increasing to 34.75% and 14.88%, respectively), implicating glutathione -transferases. RNA-seq-based genome-wide transcriptional analyses supported by quantitative PCR identified glutathione -transferase, (RNA-seqFC = 2.93 and qRT-PCRFC = 8.4, < 0.0043) and CYP450, (RNA-seqFC = 2.39 and qRT-PCRFC = 11.7, < 0.0177) as the most overexpressed detoxification genes in the pyrethroid-resistant mosquitoes, compared to mosquitoes of the susceptible Ngousso colony. Other overexpressed genes include P450s, (FC = 1.68, < 0.0114), (FC = 2.02, < 0.0005), and (FC = 1.86, < 0.0276). While high frequency of the 1014F mutation (50%) and low frequencies of 1014S (6.61%) and 1575Y (10.29%) were observed, no -1 mutation was detected in bendiocarb-resistant populations, suggesting the preeminent role of metabolic mechanism. Overexpression of metabolic resistance genes (including and known to confer resistance to multiple insecticides) in from the Sudan Savannah of Cameroon highlights the need for alternative management strategies to reduce malaria burden in northern Cameroon.
PubMed: 38410533
DOI: 10.1111/eva.13641 -
Frontiers in Plant Science 2024Rigid ryegrass ( Gaud.) is one of the most troublesome weeds in Moroccan and Tunisian cereal crop fields. In total, 19 rigid ryegrass field populations were randomly...
Rigid ryegrass ( Gaud.) is one of the most troublesome weeds in Moroccan and Tunisian cereal crop fields. In total, 19 rigid ryegrass field populations were randomly selected in northern wheat crop areas of Morocco and Tunisia to examine the patterns of herbicide resistance to acetolactate synthase (ALS)- and acetyl-CoA carboxylase (ACCase)-inhibiting herbicides. Greenhouse experiments confirmed reduced sensitivity to ALS- and/or ACCase-inhibiting herbicides in all populations. The occurrence of target-site resistance (TSR) was tested using high-throughput genotyping. The advent of next-generation sequencing (NGS) has enabled easy identification of causal mutations and confirmed the presence of ALS and ACCase mutations at specific codons conferring TSR. Thirteen populations showed resistance to ALS-inhibiting herbicides associated with point mutations in positions Pro-197-Thr, Pro-197-Ser, Pro-197-Leu, Pro-197-Gln and Trp-574-Leu, while resistance to ACCase-inhibiting herbicides was detected in 18 populations in positions Asp-2078-Val, Trp-2027-Cys, Ile-1781-Leu, Gly-2096-Ala, and Ile-2041-Asn of the enzymes conferring TSR. Additionally, dose-response experiments with pyroxsulam applied after the inhibition of cytochrome P450 monooxygenase by malathion showed an increase in sensitivity in two out of seven highly resistant (HR) rigid ryegrass populations. This demonstrates the presence of non-target-site resistance (NTSR) in some ryegrass populations. Further evidence of NTSR was investigated in dose-response experiments with pyroxsulam, following pretreatment with the glutathione -transferase (GST) inhibitor 4-chloro-7-nitrobenzoxadiazole (NBD-Cl), which partially reversed resistance in only a few individuals of two populations. Hence, our study confirms the existence of multiple and cross-resistance to ALS- and ACCase-inhibiting herbicides in from Morocco and Tunisia with both TSR and NTSR mechanisms. These results emphasize local resistance management as an important tool to detect and mitigate gene flow from rigid ryegrass populations where resistance has evolved.
PubMed: 38379946
DOI: 10.3389/fpls.2024.1331725 -
PLoS Neglected Tropical Diseases Feb 2024Insecticide resistance is a serious threat to our ability to control mosquito vectors which transmit pathogens including malaria parasites and arboviruses. Understanding...
Insecticide resistance is a serious threat to our ability to control mosquito vectors which transmit pathogens including malaria parasites and arboviruses. Understanding the underlying mechanisms is an essential first step in tackling the challenges presented by resistance. This study aimed to functionally characterise the carboxylesterase, CCEae3A, the elevated expression of which has been implicated in temephos resistance in Aedes aegypti and Aedes albopictus larvae. Using our GAL4/UAS expression system, already established in insecticide-sensitive Anopheles gambiae mosquitoes, we produced transgenic An. gambiae mosquitoes that express an Ae. aegypti CCEae3A ubiquitously. This new transgenic line permits examination of CCEae3A expression in a background in which there is not a clear orthologue in Vectorbase and allows comparison with existing An. gambiae GAL4-UAS lines. Insecticide resistance profiling of these transgenic An. gambiae larvae indicated significant increases in resistance ratio for three organophosphate insecticides, temephos (6), chloropyriphos (6.6) and fenthion (3.2) when compared to the parental strain. Cross resistance to adulticides from three major insecticide classes: organophosphates (malathion, fenitrothion and pirimiphos methyl), carbamates (bendiocarb and propoxur) and pyrethroid (alpha-cypermethrin) was also detected. Resistance to certain organophosphates and carbamates validates conclusions drawn from previous expression and phenotypic data. However, detection of resistance to pirimiphos methyl and alphacypermethrin has not previously been formally associated with CCEae3A, despite occurring in Ae. aegypti strains where this gene was upregulated. Our findings highlight the importance of characterising individual resistance mechanisms, thereby ensuring accurate information is used to guide future vector control strategies.
Topics: Animals; Aedes; Carbamates; Insecticides; Organophosphates; Temefos; Animals, Genetically Modified; Pyrethrins; Organothiophosphorus Compounds
PubMed: 38377131
DOI: 10.1371/journal.pntd.0011595