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This study evaluated the effects of abamectin and spiromesifen alone and in combination with insecticides (spinosad, acetamiprid, and emamectin benzoate) and fungicides (mancozeb and penconazole) on the red form of Tetranychus urticae Koch (Acari: Tetranychidae). The survival rates of T. urticae after abamectin, emamectin benzoate, spiromesifen, spinosad, acetamiprid, mancozeb, and penconazole treatments and in the control were 0.0%, 0.0%, 17.33% (13.3–26.6%), 17.33% (00.0–26.6%), 29.33% (13.3–40.0%), 36.00% (13.3–80.0%), 56.00% (46.6–60.0%), and 81.33% (73.3–86.6%), respectively. Binary mixtures of abamectin with spinosad, acetamiprid, and mancozeb had synergistic effects; in contrast, the abamectin mixtures with emamectin benzoate and penconazole had additive and antagonistic effects, respectively. Similarly, a binary mixture of spiromesifen showed a synergistic effect in all combinations except the mixture with penconazole. The survival rates obtained from spiromesifen alone and from spiromesifen in binary mixtures with spinosad, mancozeb, emamectin benzoate, penconazole, and acetamiprid treatments were 17.33% (13.3–26.6%), 0.0%, 6.60% (00.0–20.0%), 12.0% (00.0–26.6%), 13.3% (6.6–26.6%), and 24.0% (13.3–40.0%), respectively, with the control survival rate being 81.3% (73.3–86.6%). Ternary mixtures of abamectin showed an additive effect in all tested pesticide combinations; ternary mixtures of spiromesifen with other pesticides had an additive effect except for the spiromesifen-emamectin benzoate–mancozeb mixture, which showed an antagonistic effect. The results show that an antagonistic effect was observed in the binary mixture of abamectin with penconazole and in the ternary mixture of spiromesifen with mancozeb and emamectin benzoate. Overall, these results indicate that binary mixtures of abamectin with the triazole group of fungicides and ternary mixtures of spiromesifen with the dithiocarbamate group of fungicides and the avermectin group of insecticides could potentially lead to a decrease in treatment effectiveness against T. urticae. [ABSTRACT FROM AUTHOR]

Cyclamen mite (Phytonemus pallidus) causes injury to new growth of strawberry plants and is difficult to control because it is protected by folded leaves and plant crowns. Since cyclamen mite is easily transferred from strawberry nurseries to fruiting fields, dipping transplants in biopesticides may reduce initial populations. However, cyclamen mite numbers at 1 and 3 months-after-planting, and yield and cyclamen mite injury to fruit in the following season did not differ among transplants immersed for 30 s in Captiva® Prime, EcoTrol® EC, Landscape Oil, SuffOil-X® or Kopa Insecticidal Soap or the untreated control. Cyclamen mite is primarily controlled with foliar applications of acaricides, but there are few registered products. In greenhouse experiments, fenazaquin and pyridaben reduced cyclamen mite numbers by more than 90% in new leaves compared to the control, similar to that of the standard abamectin. New leaf injury ratings were reduced from 1 on average (scale of 0–3; 0 = no injury) pre-application to 0.25–0.5 for fenazaquin, pyridaben, and abamectin-treated plants compared to increasing to 2 for control plants 2 weeks after application. Spiromesifen and chlorfenapyr reduced cyclamen mite numbers in folded leaves in one greenhouse experiment. In the field, all acaricides reduced cyclamen mite numbers by 90–99% at 2- and 6-weeks post-application and by 75–90% at 10 months post-application. Abamectin and pyridaben resulted in 0.5–1.0% of strawberries with cyclamen mite damage compared to 3.0% for the control. All acaricides except chlorfenapyr improved strawberry yield and size. Overall, fenazaquin, pyridaben and spiromesifen should help diversify the chemical toolbox for cyclamen mite in field strawberry. [ABSTRACT FROM AUTHOR]

Pesticides serve a crucial function in contemporary farming practices, safeguarding agricultural crops against pest infestations and boosting production outputs. However, indiscriminate use has caused environmental and human health damage. This study aimed to develop and validate a gas chromatography-flame ionization detection (GC-FID) methodology for the direct and routine analysis of spiromesifen residues in soil, leaves, and tomato fruits. The proposed method prioritizes simplicity by avoiding derivatization steps, offering advantages over existing approaches that utilize lengthy multi-step extraction or derivatization prior to GC analysis. A key novelty of this work is the development of a QuEChERS extraction coupled directly to GC-FID without further clean-up or chemical treatment steps, rendering the method more convenient and accessible for routine monitoring applications. Factors evaluated included: sample solvent; inlet and column temperature profiles; inlet type; sample volume; and injection technique. Recovery and matrix effect studies were conducted by fortifying tomato, leaf, and soil matrices at three different concentrations (0.5, 1, and 10 µg ml-1). Quadruplicate analyses (n = 4) yielded mean recoveries of 98.74% (fruits), 93.92% (leaves), and 94.18% (soil), confirming efficient extraction. Matrix effects were negligible at -7.9%, -7.8%, and -5.3%, respectively. The chromatographic linearity of the developed GC-FID method was excellent over the 0.002-20 µg ml-1 range with R² > 0.9979. The method demonstrated good precision, with inter- and intra-day RSD% ranging from 0.06-1.8%, below the 3% limit. GC-MS analysis confirmed spiromesifen identification. Under greenhouse conditions, residual levels were 1.39 mg/kg in soil, 8.24 mg/kg in tomato, and 3.39 mg/kg in leaves. Dissipation followed first-order kinetics with a half-life of 1.6 days. The optimized GC-FID method is promising for monitoring spiromesifen usage and guiding agricultural practices. [ABSTRACT FROM AUTHOR]

In this study, spiromesifen and tebufenpyrad cross-resistance was investigated in Tetranychus urticae Koch (Acari: Tetranychidae) populations collected from Burdur province during the 2023 bean production season. In Burdur province, where beans are produce dintensively, 5 Tetranychus urticae populations were collected, 2 from the Central district, 2 from Çeltikçi district and 1 from Çavdır district. The dry residue method was used to determine the resistance levels of the populations. 7 insecticide doses + 1 control group were used in the trials. Each group consisted of 3 repetitions. There are 25 adult two spotted spider mite individuals in each replicate. Acaricides were applied to the leaf surface as 2 ml at 1 atm pressureusing a spraying tower. After the application, dead and living counts in the populations were made after 24 hours. Spiromesifen and tebufenpyrad resistance ratios in Tetranychus urticae populations were determined by ratioing the LC50 values of the field populations to the LC50 value of the susceptible population. As a result of the study, spiromesifen resistance ratios of B1, B2, B3, B4 and B5 populations collected from bean fields of Tetranychus urticae were 98.1, 51.5, 177.1, 130.6 and 53.6 folds, respectively; tebufenpyrad resistance ratios were determined as 2.3, 1.1, 1.8, 1.8 and 1.0 folds. Crossresistance between spiromesifen and tebufenpyrad has not been identified in two spotted spider mite populations. When the results are evaluated together, it is thought that spiromesifen should not be used in the control against Tetranychus urticae in these areas, and the use of tebufenpyrad would be more accurate. [ABSTRACT FROM AUTHOR]

To evaluate the bio-efficacy of different acaricides, an experiment was conducted against Tetranychus urticae (Koch) nourishing Dodi, Leptadenia reticulata (Ret.) Wight & Aruott and the findings revealed that abamectin 1.9 EC @ 0.00038% and spiromesifen 22.9 SC @ 0.02% were superior over other acaricides with a population reduction of 1.93 and 1.95 mites/cm2 leaf, respectively. Likewise, etoxazole 10 SC @ 0.01%, chlorfenapyr 10 SC @ 0.015% and propargite 57 EC @ 0.114% were the next effective treatments as reduced the population of mites at 3.44, 3.83 and 4.38 mites/cm2 leaf. Whereas, the lowest efficacy or highest incidence of mites was recorded in the leaves treated with dimethoate 30 EC @ 0.03% (7.25 mites/cm2 leaf) followed by sulphur 80 WDG @ 0.20% (6.77 mites/cm2 leaf) and ethion 50 EC @ 0.05% (5.82 mites/cm2 leaf). [ABSTRACT FROM AUTHOR]

Simple Summary: Cabbage whitefly (Aleyrodes proletella) is a destructive sucking insect pest of brassica crops, particularly white cabbage and kale. Its importance has been increased over the last decade in many geographic regions, particularly in European countries. The control of cabbage whiteflies largely relies on the application of synthetic insecticides to protect yield if populations reach economic damage thresholds. One class of insecticides to control this pest are cyclic ketoenols targeting acetyl-CoA carboxylase (ACC), an enzyme involved in fatty acid biosynthesis. In 2019, reduced efficacy of ketoenol insecticides at recommended label rates were reported. Subsequently, we collected field samples of A. proletella in different European countries and confirmed the presence of ketoenol resistance in laboratory bioassays. The resistance allele was shown to be an autosomal dominant trait in crossing experiments between susceptible and resistant individuals. RNA sequencing and subsequent analysis revealed a mutation, an amino acid substitution, at the ketoenol binding site in ACC. The mutation has been previously functionally validated to confer high levels of ketoenol insecticide resistance in cotton whiteflies, too. A molecular screening of 49 populations revealed the presence of the mutations in several countries. We recommend the implementation of resistance management strategies for sustainable cabbage whitefly control. Cabbage whitefly, Aleyrodes proletella L., is an invasive hemipteran pest of cruciferous plants, particularly field brassica crops. Its importance has been increased over the last decade, particularly in European countries. The control of cabbage whiteflies largely relies on the application of synthetic insecticides, including tetronic and tetramic acid derivatives such as spiromesifen and spirotetramat (cyclic ketoenol insecticides), acting as insect growth regulators targeting acetyl-CoA carboxylase (ACC). In 2019, reduced efficacy against cabbage whiteflies of ketoenol insecticides at recommended label rates has been reported. Subsequently we collected field samples of A. proletella in different European countries and confirmed the presence of ketoenol resistance in laboratory bioassays. Reciprocal crossing experiments revealed an autosomal dominant trait, i.e., heterozygotes express a fully resistant phenotype. Transcriptome sequencing and assembly of ACC variants from resistant strains revealed the presence of an ACC target-site mutation, A2083V, as previously described and functionally validated in Bemisia tabaci (A2084V in A. proletella). Next, we employed a molecular genotyping assay to investigate the geographic spread of resistance and analyzed 49 populations collected in eight European countries. Resistance allele frequency was highest in the Netherlands, followed by Germany. Finally, we provide a proposal for the implementation of appropriate resistance management strategies. [ABSTRACT FROM AUTHOR]

Spiromesifen is an agrochemical used to control sucking insect pests worldwide including Pakistan. Musca domestica is an important pest in both medical and veterinary entomology. It is a vector for many detrimental diseases in humans and animals. In this study, inheritance, and mechanism of resistance to spiromesifen were examined. After 13 rounds of selection with spiromesifen, significant increase (1092.72-fold) in resistance was observed in spiromesifen selected strain of M. domestica (SPIRO-SEL) as compared to susceptible population (SPIRO-SS). Spiromesifen toxicity was evaluated by the feeding bioassay method. Bioassays with synergists piperonyl butoxide (PBO) and S,S,S tributyl phosphorotrithioate (DEF) revealed that LC50 decreased when spiromesifen along DEF applied on SPIRO-SEL compared with spiromesifen alone that might be due to involvement of esterases. The synergistic ratios for synergists PBO and DEF to SPIRO-SEL were 1.36 and 4.36, respectively. No significant difference was observed between LC50 values of F1 and Fˆ1, which is an indication that resistance is not sex-linked. Values for degree of dominance were 0.20 and 0.23 for F1 and Fˆ1, respectively. Our results showed that inheritance of spiromesifen resistance is autosomal, polygenic, and incompletely dominant. Information obtained from these results will be helpful in developing better proactive insecticide resistance management program for M. domestica. [ABSTRACT FROM AUTHOR]

The growing resistance of Aedes aegypti (L.) to conventional insecticides presents a major challenge in arbovirus control, necessitating the exploration of alternative insecticidal chemistries. Spiromesifen, derived from spirocyclic tetronic acids, is widely used against agricultural pests and is crucial in resistance management due to its unique lipid synthesis inhibition. This study evaluates the insecticidal activity of spiromesifen against temephos-resistant Ae. aegypti populations, focusing on larval body weight, volume, biochemical composition, and adult female reproductive potential. Spiromesifen demonstrated effective larvicidal activity, significantly reducing adult emergence. Resistance to spiromesifen was not observed, with resistance ratios (RR50, RR90) ranging from 0.36- to 3.31-fold. Larvae exposed to LC50 showed significant reductions in body weight and volume, and reduced carbohydrate, lipid, and protein contents. Enhanced catalase activity and malondialdehyde levels indicated increased oxidative stress and lipid peroxidation, highlighting its effects on lipid metabolism. Spiromesifen also exhibited sterilizing effects, significantly reducing fecundity and fertility in adult females, thereby impacting Ae. aegypti reproductive capacity. These findings highlight the potential of spiromesifen as a component of integrated vector management strategies, especially in regions with prevalent insecticide resistance in Ae. aegypti, serving as an effective larvicide and impacting adult reproductive outcomes.

Chemical plant protection pro­ducts account for at least 3 % of all biosphere pollutants and are the most studied pollutants on our planet. A very significant potential risk to public health is the consumption of foodstuffs contaminated with residual quantities of pesticide compounds. The aim of the work was to assess the potential hazard to humans when eating apples and grapes treated with an insecticide based on spiromesifen. A stepwise study was used: the content of spiromesifen in apples and grapes was calculated; the risk to humans was assessed (comparing the values of the permissible daily intake of the compound with food products with the maximum possible daily intake); the integral hazard index of pesticide-contaminated products consumption was calculated and assessed. The results obtained for the determination of residual amounts of spiromesifen in apples and grapes made it possible to substantiate the value of its maximum allowable value – 0.02 mg/kg; apple and grape juices – 0.01 mg/kg. It was found that the actual intake of spiromesifen with apples and grapes can be 0.0065 mg, and this does not exceed 0.5% of the permissible daily intake, or 0.7% of the estimated permissible amount of spiromesifen that can be consumed with food. According to the value of the integral index of hazard in contaminated food consumption (6 points) spiromesifen belongs to class 3 – moderately dangerous to humans. It has been established that substantiated standards for spiromesifen make it possible to ensure the safety of consumption of grapes and apples grown with the Oberon Rapid 240 SC application, as well as the use of other pesticide formulations based on this substance on other crops.

Two spotted spider mite Tetranychus urticae Koch is an economically serious pest posing threat to major vegetable crops. Roving survey in and around Coimbatore region revealed that farmers do not target mites with acaricides instead they use higher dose of insecticides at frequent intervals which results in development of resistance. The bioassay results revealed that fenpropathrin (2.07 to 6.86-folds) and fenazaquin (2.74 to 7.13-folds) exhibit higher susceptibility, whereas diafenthiuron (5.35 to 12.25-folds) revealed a low to moderate level of resistance. The propargite (43.80 to 60.63-folds) and chlorfenapyr (61.01 to 75.10-folds) exhibited high resistance, followed by spiromesifen (222.28 to 300.26-folds) and buprofezin (382.60 to 417.87-folds), with extremely high level of resistance. The higher specific activity of GST (4.54-folds), MFO (10.06-folds) and CarE (15.06-folds) in Puthupalayam population suggested the role of biochemical resistance. A significant positive correlation was observed between diafenthiuron and CarE activity (r = 0.981*), fenpropathrin and MFO activity (r = 0.964*). [ABSTRACT FROM AUTHOR]

Insecticides are important to increase crop yields, but their overuse has damaged the environment and endangered human health. In this study, residues of spiromesifen and spirodiclofen were determined in tomato fruit using a simple and efficient analytical procedure based on acetonitrile extraction, extract dilution, and UPLC-MS/MS. The linearity range was 1–100 µg/kg and 0.5–100 µg/kg, and the correlation coefficient (R2) and residuals were ≥0.9991 and ≤16.4%, respectively. The limit of determination (LOD) was 0.26 and 0.08 µg/kg, while the limit of quantification (LOQ) was verified at 5 µg/kg. The relative standard deviation of spiked replicates at 5 µg/kg analyzed in one day (RSDr, n = 6) was ≤8.35%, and within three different days (RSDR, n = 18) it was ≤15.85%, with recoveries exceeding 91.34%. The method recovery test showed a satisfactory value of 89.23–97.22% with an RSD of less than 12.88%. The matrix effect was determined after a 4-fold dilution of the raw extract and was −9.8% and −7.2%, respectively. The validated method was used to study the dissipation behavior of the tested analytes in tomato fruit under field conditions. First-order kinetics best described the dissipation rates. The calculated half-lives were 1.49–1.83 and 1.91–2.38 days for spiromesifen and spirodiclofen, respectively, after application of the authorized and doubled authorized doses, indicating that spiromesifen dissipated more rapidly than spirodiclofen. The final residue concentrations of spiromesifen and spirodiclofen were 0.307–0.751 mg/kg and 0.101–0.398 mg/kg, respectively, after two or three applications, and were below the European Union (EU) maximum residue limits. The chronic risk assessment indicates that both insecticides are safe for adult consumers. [ABSTRACT FROM AUTHOR]

Tetranychus gloveri, a recently introduced mite species in Kerala, India has now established in the state as a predominant mite pest on ornamental plants. In this study, the status of acaricide resistance and the activity of detoxification enzymes were investigated in the populations of T. gloveri collected on Adenium plants from six different commercial horticultural nurseries of Thrissur district, Kerala, India. Adulticidal bioassays were performed for fenazaquin and dicofol, while nymphicidal bioassays were conducted for spiromesifen to estimate the LC50. The field populations showed resistance ratios in the range of 1.66–14.38-fold for fenazaquin, 1.06–27.31-fold for spiromesifen and 1.22–3.65-fold for dicofol, compared to the laboratory-maintained reference population. Enzyme assays of detoxifying enzymes revealed enhanced activity of carboxylesterase by 1.03–3.52-fold and cytochrome P450 monooxygenase by 1.01–2.08-fold in the field populations. However, the role of glutathione S-transferase in the development of resistance in different field populations was insignificant. The study recorded the development of resistance in the spider mite, T. gloveri to new generation acaricides spiromesifen and fenazaquin for the first time and also confirmed the significant role of the carboxylesterases and cytochrome P450 monooxygenases in imparting resistance in T. gloveri. [ABSTRACT FROM AUTHOR]

Chemical plant protection products account for at least 3 % of all biosphere pollutants and are the most studied pollutants on our planet. A very significant potential risk to public health is the consumption of foodstuffs contaminated with residual quantities of pesticide compounds. The aim of the work was to assess the potential hazard to humans when eating apples and grapes treated with an insecticide based on spiromesifen. A stepwise study was used: the content of spiromesifen in apples and grapes was calculated; the risk to humans was assessed (comparing the values of the permissible daily intake of the compound with food products with the maximum possible daily intake); the integral hazard index of pesticidecontaminated products consumption was calculated and assessed. The results obtained for the determination of residual amounts of spiromesifen in apples and grapes made it possible to substantiate the value of its maximum allowable value – 0.02 mg/kg; apple and grape juices – 0.01 mg/kg. It was found that the actual intake of spiromesifen with apples and grapes can be 0.0065 mg, and this does not exceed 0.5% of the permissible daily intake, or 0.7% of the estimated permissible amount of spiromesifen that can be consumed with food. According to the value of the integral index of hazard in contaminated food consumption (6 points) spiromesifen belongs to class 3 – moderately dangerous to humans. It has been established that substantiated standards for spiromesifen make it possible to ensure the safety of consumption of grapes and apples grown with the Oberon Rapid 240 SC application, as well as the use of other pesticide formulations based on this substance on other crops. [ABSTRACT FROM AUTHOR]

Water hardness can negatively affect the efficiency of pesticides. This study aimed to determine the effect of water hardness and adjuvants added to spray solution on the efficiency of insecticides. Three insecticides, namely, malathion, acetamiprid, and spiromesifen, were mixed in well water samples at 1,869, 645, and 265 mg L-1 hardness, standard, and deionized water, and applied against the second instar nymph of Bemisia tabaci using leaf dip method. In another experiment, Zero-7 at 150 ppm and Arkan at 180 ppm as additives were added to water with 1869 and 645 mg L-1 hardness, separately. LC50 values showed that the toxicity of malathion, acetamiprid, and spiromesifen was 40, 157, and 84 times less in hard water (1,869 mg L-1 hardness) than deionized water. The efficacy of malathion, acetamiprid, and spiromesifen was 13, 65, and 39 times less when they were diluted in water with 645 mg L-1 hardness than deionized water. Malathion provided 37.28 and 18.59% greater toxicity when applied in hard water containing Zero-7 and Arkan than water without the adjuvants. The efficacy of acetamiprid was, respectively, 16.93 and 18.68% greater when it was applied in hard water containing Zero-7 and Arkan compared to water without the additives. Zero-7 and Arkan in hard water enhanced the efficacy of spiromesifen by 10.26 and 13.68% compared to water without adjuvants. Generally, the toxicity of the insecticides on B. tabaci was considerably reduced at the highest levels of water hardness. In contrast, adjuvants overcame the antagonistic effects of cations in hard water. [ABSTRACT FROM AUTHOR]

Molecular identification/ characterization of Bemisia tabaci (Genn.) collected across five agroecological zones of West Bengal, India revealed that it resembles genetic group Q. Seed treatment with thiamethoxam 70WS 3 g/ kg seed incorporated with seedling treatment with acetamiprid 20SP @ 1g/ l, seedling rising under insect proof net and border netting with insect proof net showed efficacy with reducing the occurrence and dispersal of thrips Scirtothrips dorsalis Hood, mite Polyphagotersonemus latus and whiteflies B. tabaci; while their least incidence was observed with IPM module (integration of seed treatment, seedling treatment, seedling raising under insect proof net, border netting technology, installation of yellow sticky trap and need based spot application of spiromesifen and diafenthiuron), with 92.97, 82.68 and 72.97% reduction, respectively; and 98.56% reduction of chilli leaf curl virus (CLCV) incidence could be obtained through IPM with maximum yield of green chili (1.66 t/ ha). Panchagavya, dasaparni and bhramvastra appeared as potent biopesticides in reducing the CLCV causative agents. [ABSTRACT FROM AUTHOR]

Insecticides are important to increase crop yields, but their overuse has damaged the environment and endangered human health. In this study, residues of spiromesifen and spirodiclofen were determined in tomato fruit using a simple and efficient analytical procedure based on acetonitrile extraction, extract dilution, and UPLC-MS/MS. The linearity range was 1–100 µg/kg and 0.5–100 µg/kg, and the correlation coefficient (R2) and residuals were ≥0.9991 and ≤16.4%, respectively. The limit of determination (LOD) was 0.26 and 0.08 µg/kg, while the limit of quantification (LOQ) was verified at 5 µg/kg. The relative standard deviation of spiked replicates at 5 µg/kg analyzed in one day (RSDr, n = 6) was ≤8.35%, and within three different days (RSDR, n = 18) it was ≤15.85%, with recoveries exceeding 91.34%. The method recovery test showed a satisfactory value of 89.23–97.22% with an RSD of less than 12.88%. The matrix effect was determined after a 4-fold dilution of the raw extract and was −9.8% and −7.2%, respectively. The validated method was used to study the dissipation behavior of the tested analytes in tomato fruit under field conditions. First-order kinetics best described the dissipation rates. The calculated half-lives were 1.49–1.83 and 1.91–2.38 days for spiromesifen and spirodiclofen, respectively, after application of the authorized and doubled authorized doses, indicating that spiromesifen dissipated more rapidly than spirodiclofen. The final residue concentrations of spiromesifen and spirodiclofen were 0.307–0.751 mg/kg and 0.101–0.398 mg/kg, respectively, after two or three applications, and were below the European Union (EU) maximum residue limits. The chronic risk assessment indicates that both insecticides are safe for adult consumers.

Spiromesifen (SPM) is widely used for orchard mites and white fly control. The ecotoxicological data suggested that SPM is highly toxic to fish, but the information about its toxic effect on zebrafish is still obscure. In this study, adult zebrafish were exposed to SPM for 21 days. The plasma sex steroid hormone levels reflected the ratio of 17β-estradiol (E2) to testosterone (T) (E2/T) was significantly increased at 0.50 μg/L of SPM in male fish (2.4-fold, p = 0.049). Following 21 days' post exposure, distinct pathological changes were noted in gonad, males were more sensitive than female, which showed the interstitial connective tissue hyperplasia and widener in testis at 15 μg/L of SPM. In male fish, the relative percentage of spermatozoa was 13% decreased at 30 μg/L of SPM (p = 0.041). Which suggest SPM potential role in disrupting male gonad development. qRT-PCR results suggest that expression of follicle stimulating hormone receptor (fshr) was significantly down regulated in female zebrafish (0.29 fold of control, p = 0.010). Variable importance of projection (VIP) scores indicate the most important features separate in female and male. The different response of steroid level towards SPM between male and female zebrafish may due to the distinct regulation of key genes related in steroidogenesis and metabolism. This study for the first time connects the biochemical and histological to reveal the adverse effects of SPM on adult zebrafish in a sex dependent manner., (© 2024 Wiley Periodicals LLC.)

Background: Application of pesticides in modern agricultural practices is unavoidable which helps to increase the productivity through the reduction of pest attack. Simultaneously, enduring persistence of pesticides is the major issue in terms of environmental and health hazards. Hence, there is an urge to discover an ideal strategy to conquer this trouble. Objectives: The present study has been designed to isolate a bacterial strain effectively degrading spiromesifen and to test its efficiency of degradation. Materials and Methods: The bacterial strain was isolated from soil samples collected from agricultural fields after serial dilution. Based on biochemical tests, it was identified. In 2000, 3000, 4000 and 5000 ppm concentrations of spiromesifen in minimal broth, parameters like pH, CO2 released, ammonia produced and biomass were determined for every 48 hours for ten days. Results: The selected bacterial strain was identified as Serratia sp. At the time of biodegradation of spiromesifen by Serratia sp. significant level of variations were noted in the tested parameters. Conclusion: From the above findings it can be concluded that the isolated bacterial strain could be used in the treatment of pesticide contaminants in agricultural fields. [ABSTRACT FROM AUTHOR]

Abstract Background Land snails, especially the chocolate banded snails, Eobania vermiculata are destructive pests of a wide range of field and vegetable crops. New pesticides in different pesticides groups were used against the adults and eggs of chocolate banded snail, E. vermiculata under laboratory conditions. These pesticides include indoxacarb, abamectin, and spiromesifen. Other two pesticides were used against the eggs as ovicides. These two pesticides are imidacloprid and fipronil. Results The obtained results showed that indoxacarb was the most effective against the adults of E. vermiculata followed by abamectin and spiromesifen. The LC50’s were 58.6, 83.3, and 280.9 ppm, respectively. On the other hand, the recommended field rate of both fipronil and imidacloprid sharply decreased the hatchability percentage to 22.7 and 16.2%, respectively, compared with 96.3% in control. Conclusion These results cleared that indoxacarb and abamectin can be used as promising molluscicides against the adults of E. vermiculata especially in the conventional crops such as wheat and imidacloprid and fipronil can be used as soil treatment against the eggs of E. vermiculata.

Brinjal (Solanum melongena) is a versatile crop infected by several insects and pests. For the control of these pests, spiromesifen insecticide has been in use to reduce the damage and increase crop production worldwide. Therefore, a field trial was conducted to study dissipation and persistence behavior of spiromesifen 22.9% w/w SC in/on brinjal at the recommended dose (RD) 96 g a.i./ha and double to recommended dose 192 g a.i./ha (2RD). The quantitative analysis of spiromesifen was performed using ultra-high performance liquid chromatography- tandem mass spectrometry (UHPLC-MS/MS). Samples were processed by the Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method. The analytical method was validated using various parameters viz., linearity (R2≥0.99), sensitivity (LOD and LOQ), accuracy (recovery=70-120%) and precision (RSD≤20%). The spiroemsifen persisted up to 3 days at RD and 5 days at 2RD. The dissipation halflife (DT50) of spriromesifen was 3.64 and 4.10 days at RD and 2RD in brinjal, respectively. However, residues of spiromesifen measured from soil at 0th (2 hr) day and 10th day were below the limit of quantification (BQL). The waiting period deciphered for spiromesifen applied in brinjal was 1 day at the recommended dose. Further, health risk assessment (health risk index<1 and percent health index<100) was performed on the basis of field trial which suggested that the application of spiromesifen in brinjal crop at recommended dose is safe for the end-users [ABSTRACT FROM AUTHOR]

Dissipation kinetics and dietary risk assessment of spiromesifen is worked out on four summer vegetables, viz. okra, chilli, capsicum and brinjal (eggplant or aubergine) during March–April 2015 at the experimental farm of the Department of Entomology, Dr. Yashwant Singh Parmar University of Horticulture and Forestry Nauni, Solan using good agricultutral practices. Two foliar applications of spiromesifen @ 144.0 g.a.i./ha each were given at 10 days interval with a knapsack sprayer with the first application at the fruit initiation stage. Sample were collected up to 15 days after pesticide application and processed using a modified QuEChERS method, which was validated by doing recovery studies having recovery range and RSD within established guidelines of SANCO. Estimation of spiromesifen residues was conducted on GC–MS. The initial deposits after spraying of spiromesifen on okra, capsicum, chilli and brinjal fruit after 2 h of treatment were 1.327, 0.727, 0.800 and 0.738 mg/kg, respectively. The residues persisted up to 7 days and further dissipated and declined below the limit of quantification of <0.025 mg/kg at 10 days after treatment in all of the crops under investigation. Dissipation of spiromesifen followed first‐order kinetics. The spiromesifen residues dissipated to half in 1.6, 1.8, 1.9 and 1.7 days with the suggested safe waiting period of 8.9, 5.2, 6.0 and 7.0 in the respective crops. The hazard quotient was <1 and theoretical maximum dietary intake was less than the maximum permissible intake, which was less than the maximum residue limit in all of the vegetable crops under investigation. [ABSTRACT FROM AUTHOR]

Spiromesifen (Oberon® 240 SC; concentrated solution; Bayer CropScience, Germany) a pesticide derived from spirocyclic tetronic acids, acts mainly though blocking lipid biosynthesis via acetyl-CoA carboxylase. However, its mode of action requires further analyses. This study aims to evaluate the sublethal effects of spiromesifen on the fruit fly Drosophila melanogaster. The treatment was carried out by topical application on newly moulted pupae using two concentrations (LD10 = 21.45 and LD25 = 39.53 μg a.i./pupa). Our results showed that the developmental duration of larvae and pupae were not significantly affected by treatment. However, spiromesifen caused delayed effects on flies that survived from treated pupae. Spiromesifen was found to decrease significantly both the morphometric measurements and the protein contents of ovaries. The protein pattern of ovaries showed a reduction in the number of protein bands affecting the progeny via vitellogenesis. Finally, compared to controls, spiromesifen decreased significantly the amounts of some cuticular hydrocarbons in treated female and male adults. Consequently, in response to the changes in cuticular hydrocarbons, their sexual behaviour was also affected. Our study brings new insights about the multiple effects and physiological consequences of disturbing lipid metabolism. [ABSTRACT FROM AUTHOR]

The efficacy of different biocontrol agents, botanicals and a biorational insecticide were evaluated against whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae) in tomato under field conditions at Shivamogga, Karnataka during two seasons (Rabi 2018-2019 and summer 2019-2020). The results revealed that spiromesifen 240 SC @ 0.7 ml/L was the most effective in reducing the B. tabaci population i.e., 85.12 and 85.16 % reduction over untreated control during Rabi and summer, respectively followed by azadirachtin 5% @ 2 ml/l with reduction of 68.61 and 66.32 % over untreated control during Rabi and summer, respectively. The response of these treatments was also observed on the yield attributes, with highest fruit yield of 53.67 t/ha (6 pickings) in spiromesifen treatment followed by azadirachtin (52.93 t/ha), but the highest Benifit: Cost ratio was noticed in azadirachtin 5% (1:3.41), followed by spiromesifen 240 SC (1:3.38). [ABSTRACT FROM AUTHOR]

Experiment was laid out in RBD design with seven treatments comprised of pruning of affected twigs (July & October) and miticides (chlorfenapyr & spiromesifen) sprayed twice in July and once in October months to evaluate the efficacy of various integrated approaches. Results revealed that initial mite infestation ranged from 31.9 to 45.9%. During 2017-18, no mite infestation was recorded from October to fruiting stage in pruning and removal of affected twigs followed by two spraying of chlorfenapyr 10 EC (0.03%) or spiromesifen 22.9 SC (0.034%) at 15 days interval during July and again pruning in October with one spraying of chlorfenapyr or spiromesifen against 89.0% in control at fruiting stage, followed by no pruning in October along with spraying of chlorfenapyr with 7.6% mite infestation at flowering stage. Similar trend in 2018-19 confirmed that pruning in July and October followed spraying of miticides (chlorfenapyr or spiromesifen) twice in July and once in October were highly effective against litchi mite. [ABSTRACT FROM AUTHOR]

Results of a supervised field trial to study the dissipation of spiromesifen on chillies are reported. Spiromesifen 22.9 SC @ 96 and 192 g a.i. ha-1 were sprayed twice at 15 d interval from fruit initiation stage and fruit samples collected at 0 (1 h), 1, 3, 5, 7, 10, 15 and 21 d after second spray along with the control samples. A method with accepted specificity (% RSD < 2), good linearity (R² = 0.992), recovery (84.14-95.20 %) and satisfactory repeatability was developed. The LOQ and LOD of spiromesifen on chillies by UHPLC with binary gradient of CH3CN and H2O, 70:30 in an isocratic flow were 0.015 and 0.05 µg g-1 respectively. The mean initial deposits after two sprayings of spiromesifen in/on green chillies @ 96 and 192 g a.i ha-1 were 0.934 and 1.696 µg g-1, respectively. More than 80 per cent of spiromesifen residues dissipated in 3 d after treatment. The residues persisted up to 5 d @ 96 g a.i ha-1 and 7 d @ 192 g a.i ha-1. Dissipation of spiromesifen followed the first order reaction kinetics and the calculated half life was 1.36 and 1.40 d, respectively for the two respective doses, with safe waiting periods of 3.83 and 4.99 d. Washing with tap water + boiling at 100 °C (2 min + 10 min) led to 91.03 per cent reduction of residues. TMRC values of spiromesifen being less than the MPI at the recommended dose, it will not cause any ill effect on consumption of green chillies. [ABSTRACT FROM AUTHOR]

This study is on an experiment to evaluate the efficacy of some new insecticides against whitefly Bemisia tabaci (Gennadius) in cucumber grown in the polyhouse of the farmers in Koolampatti village of Sembatti block, Dindigul district, Tamil Nadu. Results revealed that abamectin 1.9%EC @ 0.5 ml was the most effective. Treatments of spinosad 2.5%SC @ 1.2 ml and chlorfenapyr 10%SC @ 1.5 ml, thiodicarb 75%WP @ 1.5 g and dimethoate 30%EC @ 1.5 ml were moderately effective. It was observed that spiromesifen 22.9 SC @ 1.0 ml was the least effective. [ABSTRACT FROM AUTHOR]

Whitefly, Bemisia tabaci (Gennadius), in North Cotton Growing Zone of India adversely affect cotton yield. Both the nymphal and adult stages of whitefly cause damage by sucking the sap from leaf tissue and honey dew secretion. In this study, the efficacy of new generation insecticides, viz. pyriproxyfen 10EC@1250 ml/ha, spiromesifen 22.9SC @500 ml/ha, flonicamid 50WG @200g/ha, and diafenthiuron 50WP @ 500g/ha were evaluated against different stages of whitefly under confined as well as field conditions in Bt cotton.The experiment conducted in screen house revealed significantly higher per cent reduction of whitefly nymphs in spiromesifen 22.9SC (49.36, 75.17) followed by pyriproxyfen 10EC (33.26, 75.07) in comparison to all other treatments after 5 and 7 days of spray, respectively. Under field conditions, pooled analysis of six experiments showed that flonicamid 50WP was more effective, being at par with pyriproxyfen 10EC, diafenthiuron 50WP, spiromesifen 22.9SC after 10 days of spray as compared to standard check, ethion 50EC and control against whitefly adults. It is concluded that pyriproxyfen10EC and spiromesifen 22.9SC have good nymphicidal action while flonicamid 50WP and diafenthiuron 50WP have adulticidal action.Therefore, for its effective management, these novel insecticides can be rotated alternatively depending upon the stage of pest dominating in the cotton field.