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A novel sanitizer tablet containing clove essential oil (CO) microemulsion was developed. A preformulation study using nuclear magnetic resonance and thermal analyses showed component compatibility. The main components of the samples remained intact despite a color change, probably due to a strong acid-base interaction between eugenol and diethanolamine. The CO microemulsion showed acaricidal and larvicidal activities superior to the commercial product, with product efficacy of 99.9% and larvae mortality of 94%. Optimal spray-drying conditions were achieved with inlet and outlet temperatures of 50°C and 40°C, respectively, an aspiration rate of 1 m3 min⁻1, and a 0.25 L h⁻1 injection flow. The feed suspension comprised 50% (v/v) liquid soap, 37.5% (v/v) water, 12.5% (v/v) ethanol, and 5.0% (w/v) silica. This formulation and processing parameters allowed for successful free-flow powder formation, providing a suitable matrix for incorporating the CO microemulsion via wet granulation without heating. Finally, sanitizer tablets produced from such granules resulted in a uniform product with low weight variation (coefficient of variation of 0.15%), eugenol content of 95.5% ± 3.3, and friability of 0.58%. Furthermore, the tablets showed rapid aqueous dispersion, forming a colloidal system with particle sizes of 221 nm and a zeta potential of -17.2 mV. Antimicrobial activity tests demonstrated the effectiveness of the sanitizer tablet against bacteria and fungi, exhibiting comparable antimicrobial potency to isolated CO. Hence, the sanitizer tablet developed represents a promising candidate as a practical and efficient solution for pest control, offering strong antimicrobial and acaricidal activity. [ABSTRACT FROM AUTHOR]

Six Corsican essential oils (EOs) from Humulus lupulus were studied for their activity against Varroa destructor adults and Apis mellifera pupae. The GC/MS analysis of EOs showed that the major compounds of all accessions were α-Humulene, Myrcene, α-Selinene, β-Selinene, (E)-β-Farnesene, and (E)-β-Caryophyllene. Bioassays showed that EOs from each accession acted as toxins and repellents against V. destructor adults, with lower toxicity towards A. mellifera pupae. In terms of efficacy against V. destructor adults, Smaragd 2020 oil displayed the highest performance, with LC50 and LC90 values of 2.33 and 7.83 µL/L air, respectively. Meanwhile, Smaragd 2019 and Tettnanger EOs showed moderate toxicity, with LC50 values of 3.101 and 3.66 µL/L air, along with LC90 values of 11.67 and 19.89µL/L air, respectively. The oils from Biguglia and Ajaccio were strongly repellent to Varroa adults. At the lowest concentration (2 µL/mL), these EOs exhibited percentage of repellence greater than 70% after 2h exposure, with RC50 values of 1.66 and 1.26 µL/L air, respectively. Concerning their insecticidal effects, EOs demonstrate reduced toxicity towards bee pupae when compared to Varroa mites. Notably, Ajaccio stands out for inducing lower mortality among bee pupae, with a selectivity ratio below 2 and LC50 of 11.25 µL/L air. [ABSTRACT FROM AUTHOR]

House mites frequently trigger allergic conditions. Although conventional treatments are effective, they can result in drug resistance and pose risks to the environment, human health, and non-target organisms. Therefore, this study evaluates new botanical extracts for their biological activities against Dermatophagoides pteronyssinus (Trouessart 1897; Pyroglyphidae), D. farinae (Hughes 1961; Pyroglyphidae), and Tyrophagus putrescentiae (Schrank 1781; Acaridae), not only to control them but also to reduce their allergens (dead bodies and faecal particles) by keeping them away. It is noteworthy that of these plants, Allium cepa L. (Alliaceae) and Solanum melongena L. (Solanaceae) peel extracts, as well as leaves of Hibiscus sabdariffa L. (Malvaceae), were tested for the first time in the present study as new bioacaricides, while Piper nigrum L. (Piperaceae) and H. sabdariffa leaves proved to be new botanical repellents for these mite species. Based on LC50 values, A. cepa, Beta vulgaris, and S. melongena extracts had the most potent toxic effects on these mite species, while extracts of Aloe vera, Capsicum annum, and P. nigrum had the strongest repellent activity against them at the highest concentration. These natural plant extracts may have valuable potential as new acaricidal products. [ABSTRACT FROM AUTHOR]

Effects of cyflumetofen and clofentezine were evaluated on Tetranychus urticae Koch, under laboratory conditions. LC50 values of cyflumetofen and clofentezine against eggs were 0.8 µg a.i./mL and 0.42 µg a.i./mL, respectively. Sublethal effects of these compounds on the life table parameters of T. urticae were evaluated by exposing mites to LC50 and LC25 concentrations. The developmental time of male and female T. urticae were significantly affected by both acaricides. Moreover, exposure to LC25 and LC50 concentrations of cyflumetofen or clofentezine significantly reduced net reproductive rate (R0), finite rate of increase (λ), and intrinsic rate of increase (r). The LC25 and LC50 treatments showed strong effects on both survivorship, fecundity, and intrinsic rate of increase. Our findings indicated that lethal and sublethal exposure to cyflumetofen or clofentezine result in significant alteration of life-history characteristics of T. urticae. Our findings suggest that these acaricides are promising candidates for use in management programs of this major pest. [ABSTRACT FROM AUTHOR]

The cattle tick Rhipicephalus (Boophilus) microplus (Canestrini, 1887) (Ixodida, Ixodidae) is responsible for significant economic losses in bovine production in tropical and subtropical regions worldwide. Control of this tick predominantly involves the use of chemical acaricides; however, their indiscriminate use has led to the selection of resistant populations. A survey on tick populations was conducted in the state of Rio Grande do Sul, in Brazil, to assess the prevalence of multiple resistance to acaricides in cattle farms. Additionally, questionnaires were administered to identify potential risk factors associated with multiple resistance to acaricides. In total, 176 farms with a bovine population of ≥40 cattle were randomly assigned for tick sampling. The resistance to six acaricidal compounds was investigated by bioassays. A larval packet test was performed for amitraz, chlorpyrifos, cypermethrin, fipronil and ivermectin. Fluazuron was screened using an adult immersion test. Multiple resistance to acaricides (i.e., resistance to three or more compounds) was detected in 173 samples, representing 98% of the total samples. Among these samples, 125 (71%) showed resistance to all six compounds tested. Additionally, we classified the resistance intensity into four levels (I to IV) based on the quartile distribution of the bioassay data. Ten samples (6%) showed high and very high levels (III and IV) of resistance to all six compounds tested. Three variables were significantly associated with multiple resistance to the six acaricides tested: (i) use of injectable acaricides to control ticks, (ii) application of more than five acaricide treatments per year, and (iii) farms with larger herds (≥232 animals). These results regarding widespread resistance and the emergence of multiple resistance to acaricides ticks are alarming and highlight the significant challenge of tick control in southern Brazil. [ABSTRACT FROM AUTHOR]

This study aims to determine the resistance ratios of Tetranychus urticae Koch red form (RF) and Tetranychus turkestani (Ugarov & Nikolskii) populations collected from cotton fields in Soke, Germencik, Kocarli and Nazilli districts of Aydin province to commonly used acaricides (abamectin, hexythiazox, etoxazole, spiromesifen). The potential role of detoxification enzymes (esterase, glutathione-s-transferase (GST), P450 monooxygenase (P450)) in acaricide resistance was also assessed. Overall populations of T. urticae RF presented varying ratios of resistance to these acaricides with all three populations (G15R21, K24R21, S3R21) showing significant resistance to abamectin (187.1–223.66 fold), hexythiazox (156.31–168.25 fold), etoxazole (409.58–517.20 fold) and spiromesifen (981.77–1246.11 fold). In contrast, all five T. turkestani populations (G4G21, K16G21, N1G21, N11G21, S19G21) were susceptible to abamectin, etoxazole, and spiromesifen, but exhibited some resistance to hexythiazox (164.34–182.39 fold). The resistance ratios of T. turkestani were however lower compared to T. urticae RF. A relationship was also found between detoxification enzymes and resistance. Esterase activity varied among mite populations, with the highest levels recorded in resistant populations of T. urticae (G15R21 and K24R219) with rates ranging between 6.48 and 7 mOD/min/mg protein. GST activity was highest in resistant mite populations (T. urticae S3R21 and T. turkestani K16G21). T. turkestani N11G21 population exhibited the highest P450 enzyme activity, reaching 4.39 RFU/30 min/mg protein. This study was the first to determine the resistance ratios of T. turkestani to hexythiazox in Türkiye, and on a global scale. [ABSTRACT FROM AUTHOR]

Two-spotted spider mite (Tetranychus urticae Koch, 1836, Acari: Tetranychidae) causes significant yield losses in cultivated plants, especially depending on the season. Chemical methods are the main methods of controlling this pest. However, besides the environmental, human, and animal health problems arising from chemical control, adverse effects such as resistance and residues limit the success and sustainability of chemical control. This experiment was conducted in the applied acarology laboratory of the Directorate of Plant Protection Central Research Institute in Ankara, Türkiye, in incubators maintained at 25 ± 1 °C temperature, 50–65% humidity, and 16 L: 8 D h photoperiod. In this study, the potential acaricidal effect of aqueous extracts of Morus rubra, Daphne odora, Ficus carica, Matricaria chamomilla, and Mentha pulegium collected from Ankara and Adana provinces on T. urticae was investigated. For this purpose, the leaves of the plants were dried and ground and 1%, 3%, 6%, and 12% concentrations (w/v) of the extracts obtained were tested in three different application periods (1–6 day). Dipping and spraying methods were used to determine mortality and toxicity. The highest effect was 94.4% at the end of the 6th day at a 12% concentration of M. pulegium in the dipping method. On the other hand, the lowest mortality effect was 18.2% at the same time and concentration of M. chamomilla. In lethal toxicity studies, the highest toxicity was obtained from F. carica with an LC50 value of 4756 mg L−1, and the lowest toxicity was obtained from D. odora with an LC50 value of 12,417 mg L−1. We believe that plant extracts provide a valid alternative in effectively controlling two-spotted spider mites, reducing the need for pesticide use and minimizing residues. [ABSTRACT FROM AUTHOR]

Background: Brown dog ticks (Rhipicephalus sanguineus sensu lato) are vectors of pathogens adversely affecting the health of dogs in many regions of the world. The three-host life cycle of R. sanguineus s.l., with all stages feeding on dogs, can lead to an uncontrolled build-up of large tick populations if not controlled by acaricides. However, frequent tick control on dogs using acaricides has led to the emergence of resistance to permethrin and fipronil. Currently, the larval packet test (LPT) is the standard tick resistance test, which is laborious, requires laboratory facilities, and takes at least 6 weeks before larvae derived from engorged female ticks can be tested. Our novel approach is to expose semi-engorged adult ticks to acaricides immediately after removing them from dogs, obtaining results within 24 h. Methods: Adult ticks from three laboratory colonies of R. sanguineus s.l. were tested in RaTexT®, a rapid tick exposure test in which ticks were confined to small compartments and exposed to an acaricide-impregnated, specially designed matrix. Resistance was confirmed by testing larvae derived from the same laboratory colonies using the LPT. RaTexT® was also used to determine the susceptibility of R. sanguineus acaricides in dog shelters. Results: RaTexT® detected resistance to permethrin in adult R. sanguineus s.l. ticks from two Brazilian laboratory colonies compared to a susceptible laboratory strain originating in Greece. Resistance was confirmed by LPT testing of larvae from the same colonies with resistance factors between 2.2 and 3.1. All laboratory strains were susceptible to fipronil. A suspected case of fipronil resistance at a dog shelter in Caxias do Sul, Brazil, was resolved within 24 h by testing adult ticks in RaTexT® and could be attributed to improper treatment. Conclusions: RaTexT® is a valuable tool for monitoring the development of resistance to synthetic pyrethroids or phenylpyrazoles in tick-infested dogs. [ABSTRACT FROM AUTHOR]

Seven acaricides were selected in the toxicity test on Tetranychus urticaris that break out on Clematis L.. Slide impregnation, leaf disk and toxicity test on pot were applied respectively for eggs, female adults and single population on plant in toxicity test. Results indicated that the order of curative effect from good to bad was matrine, abamectin+pyridaben, buflomedin, bifenazate+etoxazole, abamectin+etoxazole, spirodiclofen and bifenazate. Toxicity test on pot showed that the LC50 value were higher than that in slide impregnation and leaf disk test. Morever, the LC50 values that we obtained in this study were higher than previously reported LC50 values of T. urticaris that live on other plants which indicated that T. urticaria colonized on Clematis L. had higher tolerance to pesticides. This study would be helpful in providing theoretical basis for T. urticaria chemical control. [ABSTRACT FROM AUTHOR]

Bacillus thuringiensis (B. thuringiensis) is considered one of the most important entomopathogenic microorganisms. It produces potent toxins against insects. Therefore, the present study investigates the bioacaricidal properties of B. thuringiensis on the Hyalomma tick species. Firstly, we identify Hyalomma ticks based on morphological screening and molecular characterization. The cytochrome C oxidase subunit I (COX1) gene was selected for the polymerase chain reaction (PCR) analysis, which resulted in the amplification of 656 bp. The amplified products were sequenced, and the isolated (COX1) gene of ticks was submitted to the gene bank of NCBI (Accession No. OR077934.1). The nucleotide sequences were retrieved from the NCBI data bank by BLASTn analysis, which confirmed that all obtained sequences belong to genus Hyalomma, and multiple alignments confirmed that the sequence of Hyalomma anatolicum Tandojam‐isolate (HA‐TJ) 100% aligned with Hyalomma analoticum KP792577.1, Hyalomma detritum KP792595.1, Hyalomma excavatum KX911989.1, and H. excavatum OQ449693.1. The generated phylogenetic tree confirmed that sequences of HA‐TJ COX1 clustered with a single clad of H. analoticum, H. excavatum, and H. detritum. The acaricidal effect of B. thuringiensis toxins B. thuringiensis spore crystal mix (BtSCM) and B. thuringiensis crystal proteins (Btcps) was evaluated against larvae and adult life stages of Hyalomma ticks in vitro. We applied Btcps and BtSCM separately with different concentrations and calculated the mortality percentage. Adult mortality was estimated at the 8th, 10th, 12th, and 15th days posttreatment and larval mortality after 24 h. During treatment of the adult life stage, at first, ticks were immersed in different concentrations of Btcps and BtSCM for 5 min after the treatments, and the samples were transferred to sterile containers and placed in an incubator with 80% humidity at 23°C. Furthermore, Btcps produced the highest mortality on Day 15, 89 ± 1.00% at a concentration of 3000 μg/mL, followed by the 12th, 10th, and 8th days produced 83 ± 1.91%, 70 ± 1.15%, and 61 ± 1.00%, respectively. BtSCM produced mortality of 69 ± 1.91% on Day 15 at a concentration of 3000 μg/mL, followed by the 12th, 10th, and 8th days at 57 ± 2.51%, 37 ± 1.91%, and 34 ± 2.00%. The present study revealed that B. thuringiensis toxins produced a significant (p < 0.05) increase in mortality rate in adults of Hyalomma ticks. Additionally, Btcps and BtSCM were used to treat the larval stage. The treatments were applied to calculate the mortality percentage via the Laravel packet test. At a 1500 μg/mL concentration, Btcps resulted in the highest mortality of 98 ± 1.15%; this was followed by 1250 μg/mL, 1000 μg/mL, and 750 μg/mL, which produced mortalities of 76 ± 1.63%, 60 ± 1.63%, and 56 ± 1.63%, respectively. In addition, BtSCM produced a mortality rate of 79 ± 2.51% at a concentration of 1500 μg/mL. Furthermore, 75 ± 2.51%, 65 ± 1.91%, and 58 ± 1.15% mortality were observed at concentrations of 1250 μg/mL, 1000 μg/mL, and 750 μg/mL, respectively. The results showed a significant (p < 0.05) increase in larval mortality compared to the control group. We conclude that B. thuringiensis toxins are applicable as a bioacaricide. [ABSTRACT FROM AUTHOR]

This study was designed to evaluate the acaricidal effect and the mode of action of lemongrass essential oil (LEO) against Aleuroglyphus ovatus. Contact and fumigant mortality indicated that LEO had higher acaricidal activities at a low concentration, and the acaricidal action of LEO was significantly more effective by contact effects than by fumigant bioassay. Repellent rate against A. ovatus at different concentrations of LEO increased with application time. Observation on the toxic symptoms revealed that almost all mites were in immobilized type (IM type) in 30 min, but the symptom of knock-down type (KD type) appeared later. Cuticles of mites killed by LEO exhibited obvious colour change and deformation. Detoxification enzyme activity assay showed that glutathione S-transferase (GST) activity increased in mites treated by LEO compared to the controls. LEO increased catalase (CAT) activity of A. ovatus but inhibited superoxide dismutase (SOD) after 20 h. LEO also increased nitric oxide synthetase (NOS) and inhibited acetylcholine esterase (AChE) activities. Moreover, LEO acted as a fast-acting neurotoxin on A. ovatus. Our results suggest that LEO has an acaricidal potential and is a promising agent in control of A. ovatus. [ABSTRACT FROM AUTHOR]

Proprioseiopsis asetus and Amblyseius swirskii are excellent natural enemies of plant-feeding mites and small pests. In order to clarify the safety of the acaricide spirodiclofen to the predatory mites P. asetus and A. swirskii, here, we investigated the toxicity of the acaricide on the pest mite T. urticae (nymphs and adult females) and on both species of predatory mites, P. asetus and A. swiskii (eggs, nymphs, and female adults) by using the spray, slide-dip, and leaf residual toxicity methods, compared the selective toxicity and assessed the safety to these natural enemies. The results demonstrated that the corrected mortality in P. asetus and A. swirskii female adults was <5% at recommended spirodiclofen concentrations in the spray method. In the leaf residual toxicity method, P. asetus and A. swirskii egg-hatching rates did not differ significantly from the pure water control group. In the slide-dip method, spirodiclofen lethal concentration 50 (LC50) in P. asetus and A. swirskii female adults was noted to be 9,494.875 and 3,064.187 mg·L–1, respectively. In the spray method, spirodiclofen LC50 in P. asetus and A. swirskii nymphs was found to be 4,292.664 and 1,081.609 mg·L–1, respectively, and that in T. urticae female adults and nymphs was 55.189 and 40.862 mg·L–1, respectively. Spiroclofen selective toxicity ratios (STRs) in P. asetus female adults–T. urticae and P. asetus nymphs–T. urticae were 172.013 and 105.053, respectively, indicating that spiroclofen has a high positive selectivity toward the pest T. urticae and its natural enemy P. asetus. In contrast, spiroclofen STRs in A. swirskiis female adults–T. urticae and A. swirskiis nymphs–T. urticae were 55.522 and 26.470, respectively, indicating spiroclofen has a moderate positive selectivity toward the pest T. urticae and its natural enemy A. swirskii. In the safety evaluation, the spirodiclofen safety factor for P. asetus female adults and nymphs was 158.248–237.37 and 71.544–107.317, respectively, whereas that for A. swirskii female adults and nymphs was 50.070–76.605 and 18.027–27.040 respectively. All spirodiclofen safety factor values were much higher than 5, indicating that spirodiclofen is highly safe for P. asetus and A. swirskii; in particular, spirodiclofen is safer for P. asetus than for A. swirskii. [ABSTRACT FROM AUTHOR]

Citrus leprosis mite [Brevipalpus yothersi Baker (Acari: Tenuipalpidae)] is traditionally controlled with acaricide applications using a high volume of spray solution (> 2000 L.ha-1). However, high spray solution volumes can generate water waste and environmental contamination. An experiment was set up in a sweet orange orchard located in the municipality of Taquaral, São Paulo, Brazil, aiming to optimize the spray solution volume required for more efficient control of the leprosis mite. The experiment was conducted from December 2020 to July 2022. Two spray solution volumes were evaluated: 100 and 180 mL m–3 of plant canopy. In total, seven acaricide applications were performed. During the experiment, we assessed the incidence and infestation of the leprosis mite. Additionally, at the end of the experiment, we counted the number of plants and fallen fruits exhibiting leprosis symptoms. The treatment with a spray volume of 180 mL m–3 was more effective in controlling mites, as the incidence and infestation of B. yothersi were lower in this treatment. Moreover, this treatment resulted in fewer plants with fallen fruits and a reduced number of fallen fruits showing leprosis symptoms. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the acaricidal efficacy, tolerability of the target species, and residue levels of a thymolcontaining gelatin-based hydrogel developed as a controlled release system for varroosis control. The study was carried out on naturally infested honey bee colonies and results were compared with those of negative and positive control groups. The acaricidal efficacy of the negative control, positive control, and hydrogel treatment was 21.93 ± 2.87%, 81.09 ± 2.30%, and 70.32 ± 2.05%, respectively. For tolerability evaluations, the average number of dead bees per colony was determined to be 60.80 ± 8.01, 297.40 ± 21.4, and 86.80 ± 6.94 for the negative control, positive control, and hydrogel treatment, respectively. The average thymol residues in honey were measured as 0.030 ± 0.022 mg/kg, 5.498 ± 3.346 mg/kg, and 0.168 ± 0.110 mg/kg for the negative control, positive control, and hydrogel treatment, respectively. The average thymol concentrations in beeswax were 0.074 ± 0.047 mg/kg, 1.667 ± 0.855 mg/kg, and 0.476 ± 0.278 mg/kg for the negative control, positive control, and hydrogel treatment, respectively. The controlled release system developed in this study was found to prevent the transport of thymol out of the colony due to its structure, which is well tolerated by bees. Consequently, a single application can achieve longer infestation control. Furthermore, the lack of intervention by bees in the system ensures that bee mortality due to contact toxicity and residue levels in honey and beeswax are low. In addition to these advantages of the system, further development is required to increase the acaricide efficacy in order to make it an ideal alternative to existing varroacidal veterinary medicinal products. [ABSTRACT FROM AUTHOR]

Simple Summary: The mite Varroa destructor is the most damaging parasite of honey bees (Apis mellifera) worldwide. When necessary, mite control is mainly accomplished with acaricides. Optimal parasite control is achieved when the acaricide is applied during times of little or no brood in honey bee colonies, which varies by region. Therefore, in this study we analyzed the population dynamics of the mite in honey bee colonies established in a temperate semi-arid climate in Mexico by periodically sampling brood and adult bees, as well as by counting mites falling to the bottom board of hives over 10 months. We also measured brood and adult bee populations and food stores. It was found that the sampling period influences the population of V. destructor in the colonies. The mite population increased by 26% in the 10 months of sampling. It was observed that as the worker brood population increased, the mite infestation rate in adult bees decreased, and the opposite occurred when the amount of brood in the colonies was reduced. Monitoring V. destructor populations by recording fallen mites is more reliable than determining mite infestation rates in adult bees and brood. The best period to apply an acaricide treatment in the region of study is between November and December. This study aimed to analyze the population dynamics of the mite Varroa destructor in honey bee (Apis mellifera) colonies in a temperate semi-arid climate in Mexico. Ten colonies homogeneous in population, food stores, and levels of mite infestation were used. The mite infestation rate in brood and adult bees, total number of mites, daily mite fall, brood and adult bee population, and food stores were determined periodically for 10 months. There was a significant effect (p < 0.05) of sampling period on the population of V. destructor in adult bees, brood, total mite population, and daily fallen mites. The total mite population increased by 26% on average per colony. The increase in brood amount reduced the mite infestation rate in adult bees, and the opposite occurred when the brood decreased. Monitoring V. destructor populations by recording fallen mites is more reliable than determining mite infestation rates in bees, as mite fall has a dynamic pattern similar to that of the total mite population. The best period to apply an acaricide treatment in the region of study is between November and December because most mites were in the phoretic phase, since there was less brood in the colonies compared to other times. [ABSTRACT FROM AUTHOR]

Simple Summary: Pyridaben is an efficient, low-toxicity, broad-spectrum insecticide that impairs the predatory capabilities of predatory mites, but the specific mechanisms that affect the predatory functions remain underexplored. This study elucidated that pyridaben significantly diminished the predatory efficiency and searching behavior of the predatory mite Neoseiulus womersleyi. A gene linked to olfactive functions, NwNPC2a, was cloned from N. womersleyi. Post-treatment with pyridaben at LC30 and LC50 concentrations resulted in a substantial downregulation of NwNPC2a expression. Silencing NwNPC2a in N. womersleyi females led to significant reductions in predatory functions. The decrease in predatory performance at LC30 and LC50 concentrations was attributable to the suppression of NwNPC2a gene expression. Thus, the underlying molecular mechanism through which pyridaben compromises the predatory function of N. womersleyi likely involves the downregulation of NwNPC2a expression. Pyridaben is a widely utilized, broad-spectrum contact acaricide, which has notable sublethal effects that impair the predatory capabilities of predatory mites, but the specific mechanisms that affect the predatory functions remain underexplored. When predatory mites hunt for prey, they may rely on Niemann–Pick-type C2 (NPC2) proteins to collect herbivore-induced plant volatiles (HIPVs) and other odor molecules to locate and pursue their prey. This study elucidated that pyridaben significantly diminished the predatory efficiency and searching behavior of the predatory mite Neoseiulus womersleyi. Key metrics, including predatory capacity (a/Th) and predation rate (a) on various developmental stages of Tetranychus urticae, were markedly reduced in treated mites compared to controls. The searching efficiency (S) also declined proportionally with the increased sublethal dose of pyridaben. A gene linked to olfactive functions, NwNPC2a, was cloned from N. womersleyi. Post-treatment with pyridaben at LC30 and LC50 concentrations resulted in a substantial downregulation of NwNPC2a expression by 60.15% and 58.63%, respectively. Silencing NwNPC2a in N. womersleyi females led to significant reductions in the attack rate (a), handling time (Th), predation efficiency (a/Th), and maximum predation rate (1/Th). The searching efficiency (S) was also lower than that of the control group, displaying a slight decline with the increasing prey density. The findings revealed that pyridaben exerted inhibitory effects on both the predatory function and searching efficiency of N. womersleyi populations. The decrease in predatory performance at LC30 and LC50 concentrations was attributable to the suppression of NwNPC2a gene expression. RNA interference (RNAi) studies corroborated that the NwNPC2a gene plays a critical role in the predation process of N. womersleyi. Thus, the underlying molecular mechanism through which pyridaben compromises the predatory function of N. womersleyi likely involves the downregulation of NwNPC2a expression. [ABSTRACT FROM AUTHOR]

Development of acaricide resistance in tick population is a major concern in livestock as well as in pet animals. Reduced responsiveness has been observed against commonly used acaricides in Rhipicephalus sanguineus tick infested dogs in the Agartala city of North-eastern part of India. Two acaricides Deltamethrin and Fipronil were chosen for acaricidal resistance study using Adult Immersion Test (AIT) and Larval Packet Test (LPT). AIT study revealed the lowest and highest mortality of adult ticks at 25 ppm and 200 ppm concentration of Deltamethrin, respectively. Similarly for fipnonil, lowest and highest mortality was recorded at 25 ppm and 100 ppm, respectively. With increasing the concentration of both deltamethrin and fipronil, the reproductive index of ticks was found to be decreased with increased inhibition of oviposition. In LPT study, lowest mortality of R. sanguineus larvae was recorded at 25 ppm of deltamethrin and highest mortality at 200 ppm. For fipronil, lowest and highest mortality was recorded at 25 ppm and at 100 ppm, respectively. The study revealed that both the acaricides produced lower mortality of ticks at their market recommended doses. However, fipronil was found to be more effective than that of deltamethrin. The observed resistance warrants immediate measures to prevent further development of acaricide resistance in tick population in dogs in the study area. [ABSTRACT FROM AUTHOR]

The emergence of tick resistance against synthetic and eco-toxic chemical acaricides has stressed the need to find target-specific, non-toxic, and more potent alternatives such as botanicals. The current study was designed to investigate the acaricidal and repellent potential of ethyl acetate extract of Moringa oleifera seeds against Rhipicephalus microplus cattle ticks. Adult immersion test, larval immersion test, and tick climbing repellent assay were carried out to evaluate the acaricidal and repellent potential of M. oleifera extract. Five different concentrations (20, 10, 5, 2.5, and 1.25 %) of the ethyl acetate extract of M. oleifera were prepared to evaluate the acaricidal and repellent potential. Different parameters like adult tick mortality, larval mortality, egg hatchability, inhibition of egg hatchability, oviposition reduction, reproductive index, reproductive efficiency index, tick repellency, and product effectiveness were determined. Ethyl acetate extract of M. oleifera showed 70% adult mortality after 24 h treatment when 20% concentration was used. Similarly, 73% larval tick mortality was observed at 20% concentration. The results also showed the dose-dependent response of ethyl acetate extract of M. oleifera seeds against egg hatchability, inhibition of egg hatchability, oviposition reduction, reproductive index, reproductive efficiency index, and tick repellency, confirming that 20% concentration is effective as an acaricide and repellent against R. microplus. Therefore, the tested extract can be considered a possible candidate for controlling R. microplus in cattle. [ABSTRACT FROM AUTHOR]

Background: Tick-borne diseases are an emerging threat to public health throughout the temperate world, leading to a growing field of research aimed at developing and testing intervention strategies for reducing human-tick encounters or prevalence of infection in ticks. Various wide-spectrum chemical acaricides have proven effective for controlling tick populations, but many of these have potential deleterious side-effects on health and the environment. In addition to chemical acaricides, certain compounds such as diatomaceous earth have been shown to have physical acaricidal properties. We hypothesized that dolomitic lime (CaMg(CO3)2, a corrosive, desiccant mineral that is already used extensively in agricultural and forestry contexts to balance the pH of soils, may affect ticks' locomotory activity, habitat position, or survival and that this should manifest as a reduction in the number of questing ticks collected by dragging. Objective: This study aimed to formally assess this hypothesis in a controlled laboratory setting. Methods: We carried out a microcosm experiment, with one control and three treated microcosm trays, each replicating the natural substrate characterizing I. scapularis habitat in northeastern North America. Each tray was infested with 200 living larvae and 50 nymphs, and then treated with 0 (control), 50, 100, or 500 g/m2 of lime powder. Ticks were collected by microdragging 24 and 72 h postliming. Results: Efficacy of liming at reducing the number of collected questing ticks ranged from 87% to 100% for larvae and 0% to 69% for nymphs 24 h postliming and from 91% to 93% for larvae and −47% to 65% for nymphs 72 postliming. Conclusion: This study provides the first experimental evidence of the potential efficacy of liming for impairing activity of questing immature ticks. Given that lime is a low-cost material, that methods for widespread application in deciduous woodlands already exist, and that it has been documented as having a limited negative impact on the environment, further assessment of lime application as a public health risk reduction intervention for tick-borne diseases is warranted. [ABSTRACT FROM AUTHOR]

Background: Acaricide resistance in cattle ticks is a significant concern in (sub)tropical regions, particularly Brazil. The Larval Packet Test (LPT) is the standard laboratory bioassay for resistance diagnosis, which requires triplicates of seven acaricidal dilutions plus controls to cover larval mortalities ranging between 0 and 100%. The value of the LPT lies in providing resistance ratios based on the ratio between the LC50 calculated with potentially resistant and susceptible ticks. However, LC50 ratios are difficult to translate into practical advice for farmers. Moreover, LPT requires laboratory facilities to maintain susceptible tick colonies, and it takes 6 weeks to obtain the larvae to be tested by LPT derived from engorged female ticks collected from cattle in the field. Our novel approach was twofold: first, we upgraded the LPT to the Resistance Intensity Test (RIT) by adopting the latest WHO guidelines for resistance detection in mosquitoes, which combines a 1 × recommended dose with 5 × and 10 × concentrated doses to reveal low, moderate and high resistance intensity, respectively. This reduced the number of test papers and tick larvae and, more importantly, provided relevant information on the resistance level. Our second innovative step was to abolish testing larvae entirely and expose partly engorged adult ticks to the same acaricidal doses immediately after removing them from cattle in the field. This resulted in the Rapid Tick exposure Test (RaTexT®), wherein partly engorged adult ticks were exposed to an acaricide-impregnated, specially designed matrix providing test results within 24 h. This approach directly compared resistance detection in tick larvae in the RIT with resistance in adult ticks in RaTexT®. Methods: Laboratory validation was conducted in Brazil with resistant and susceptible colonies of Rhipicephalus microplus ticks. For field validation, adult R. microplus ticks collected from different cattle farms in Brazil were evaluated for resistance to RaTexT®, and the results regarding their larval progenies were compared with those for the RIT. Partly engorged adult ticks derived from cattle infested with laboratory and field strains of R. microplus were exposed to deltamethrin in RaTexT® containers, which contained six rows of four interconnected compartments, accommodating five to eight semi-engorged female ticks with a preferred size ranging between 5 and 8 mm. The corresponding larvae of each strain were exposed in the RIT to the same deltamethrin concentrations in filter papers. Results: In RaTexT®, mortality in adult ticks from a resistant strain of R. microplus from Seropédica in Brazil was 38.4%, 54.2% and 75.0% at the 1 ×, 5 × and 10 × doses of deltamethrin, respectively. In RIT, mortality of larvae from the same resistant strain was 2.0%, 4.9% and 19.5% at 1 ×, 5 × and 10 × doses, respectively. The results of RaTexT® and RIT agreed since both tests identified a high level of resistance based on a cut-off of 90% mortality. In RaTexT®, mortality of adult ticks from a susceptible strain originating from Porto Alegre was 73.8%, 92.9% and 97.6% at the 1 ×, 5 × and 10 × doses, respectively. In RIT, mortality of larvae from the susceptible strain was 95.2%, 95.2% and 96.8% at the 1 ×, 5 × and 10 × doses, respectively. Interestingly, both tests identified a low number of unexpected resistant individuals in the susceptible strain since the mortality of neither larvae nor adults reached 100%. This effect remained unnoticed in the LPT, wherein a resistance ratio of 159.5 was found based on the LC50 of the resistant strain divided by the LC50 of the susceptible strain. Next, RaTexT® was compared with RIT using adult and larval ticks derived from three field strains of R. microplus in Brazil. RaTexT® detected high levels of resistance to deltamethrin in adult ticks in all strains, which was confirmed in larvae tested by the RIT. Both tests agreed on the same resistance level with significantly lower mortality rates in larvae than in adult ticks. Conclusions: RaTexT® is a novel rapid pen-site test for detecting acaricide resistance in adult livestock ticks. It potentially replaces laborious tests using larval ticks and provides results within 24 h relevant to acaricide resistance management of livestock ticks. [ABSTRACT FROM AUTHOR]

Plants are attacked by diverse herbivorous pests with different host specializations. While host plant resistance influences pest pressure, how resistance impacts the behaviors of generalist and specialist herbivores, and the relationship to resistance, is less well known. Here, we investigated the short-term (< 1 h) behavioral changes of a generalist herbivore, the two-spotted spider mite (TSM), and a specialist herbivore, the Banks grass mite (BGM), after introduction to no-choice Tanglefoot leaf-arenas (2 × 2 cm) of three maize inbred lines (B73, B75, and B96). The widely-used inbred line B73 is susceptible to spider mites, while B75 and B96 are known to be mite resistant, especially to TSM. Video tracking was used to record TSM and BGM walking, probing, feeding, resting, web-building and travel distance on arenas of each line. Mite oviposition was also recorded after 72 h. B75, a resistant line, decreased the feeding behavior (i.e., time) of both mite species compared to B73 (susceptible control) and B96. Moreover, TSM appeared to be sensitive to both resistant lines (B75 and B96) with reduced oviposition, and increased resting and web-building times compared to susceptible B73. In contrast, the specialist BGM showed no difference in oviposition, resting and web-building time across all maize inbred lines. Our findings of quite broad and short-term responses of TSM to B75 and B96 are consistent with a role for constitutive or rapidly induced plant defenses in maize in conferring TSM resistance. Other mechanisms of plant resistance may be needed, however, for defense against specialists like BGM. [ABSTRACT FROM AUTHOR]

Background: Pyrethroid chemicals are one of the main acaricides used against ticks. Resistance to these chemicals has been reported to be associated with mutations in the voltage-gated sodium channel (VGSC) gene of the Rhipicephalus microplus. This study investigates R. microplus resistance to pyrethroids in Guangxi region of China, marking one of the first research efforts in this area. The findings are intended to provide vital baseline for the effective implementation of localized tick control strategies. Methods: From March to July 2021, 447 R. microplus tick samples were collected from five prefecture-level cities in Guangxi. Allele-specific polymerase chain reaction (AS-PCR) was used to amplify segments C190A and G215T of the domain II S4-5 linker and T2134A of domain III S6 in the VGSC, to detect nucleotide mutations associated with resistance to pyrethroid acaricides. Subsequent analyses were conducted to ascertain the prevalence, types of mutations, and genotypic distributions within the sampled populations. Results: Mutations within VGSC gene were identified across all five studied populations of R. microplus, although the mutation rates remained generally low. Specifically, the most prevalent mutation was C190A, observed in 4.9% of the samples (22/447), followed by G215T at 4.0% (18/447), and T2134A at 1.3% (6/447). The distribution of mutations across three critical sites of the VGSC gene revealed four distinct mutation types: C190A, G215T, C190A + G215T, and T2134A. Notably, the single mutation C190A had the highest mutation frequency, accounting for 4.3%, and the C190A + G215T combination had the lowest, at only 0.7%. The analysis further identified seven genotypic combinations, with the wild-type combination C/C + G/G + T/T predominating at a frequency of 90.4%. Subsequently, the C/A + G/G + T/T combination was observed at a frequency of 4.3%, whereas the C/C + T/T + T/T combination exhibited the lowest frequency (0.2%). Additionally, no instances of simultaneous mutations at all three sites were detected. Geographical differences in mutation types were apparent. Both samples from Hechi to Chongzuo cities exhibited the same three mutation types; however, C190A was the most prevalent in Hechi, while G215T dominated in Chongzuo. In contrast, samples from Beihai to Guilin each exhibited only one mutation type: G215T occurred in 12.5% (4/32) of Beihai samples, and C190A in 7.5% (4/53) of Guilin samples. Conclusions: These findings underscore the relatively low frequency of VGSC gene mutations in R. microplus associated with pyrethroid resistance in the Guangxi, China. Moreover, the variation in mutation types and genotypic distributions across different locales highlights the need for regionalized strategies in monitoring and managing pyrethroid resistance in tick populations. This molecular surveillance is crucial for informing targeted control measures and mitigating the risk of widespread resistance emergence. [ABSTRACT FROM AUTHOR]

The twospotted spider mite (TSSM), Tetranychus urticae Koch (Acari: Tetranychidae) is a major pest of field and greenhouse crops leading to qualitative and quantitative losses. Various chemical‐based acaricides are being used for its management that pose risks to human health, environment and non‐targeted organisms besides the development of resistance and resurgence of the pests. Therefore, alternative mite management practices are being promoted and implemented. Amongst them, entomopathogenic fungi (EPF) like Beauveria bassiana and Metarhizium spp. are being used globally, although new alternative EPF are required. Keeping this in mind, the present study was comprehended to determine the pathogenicity of native EPF, viz., Tolypocladium inflatum (Hypocreales: Ophiocordycipitaceae) and Clonostachys krabiensis (Hypocreales: Bionectriaceae) against different life stages of TSSM under laboratory conditions. The results indicated that adults are more vulnerable to studied fungi followed by nymphs and eggs of TSSM. The combined application of T. inflatum and C. krabiensis was significantly effective in controlling TSSM adults (99.33%) followed by T. inflatum (93.34%) and C. krabiensis (85.33%). According to the probit analysis, the combined application of studied EPF was found to be more effective against TSSM adults (LC50 = 6.72 × 104 conidia/mL) followed by T. inflatum (LC50 = 1.92 × 106 conidia/mL) and C. krabiensis (LC50 = 7.90 × 106 conidia/mL). All three treatments at higher concentrations significantly reduced the adult and nymph populations. Morphological investigations using scanning electron microscopy revealed the successful conidial adhesion, germination and penetration of native T. inflatum and C. krabiensis conidia on TSSM adults. Thus, the acaricidal potential of isolated native fungi can further be explored for developing fungal‐based formulations for the sustainable management of mites. [ABSTRACT FROM AUTHOR]

An experiment was conducted during March-April, 2018-19 and 2019-20 in the Department of Agricultural Entomology, Uttar Banga Krishi Viswavidyalaya, Pundibari, Cooch Behar, West Bengal, India to evaluate the duration of residual toxicity of five conventional as well as recently introduced acaricides against red spider mite, Oligonychus coffeae on tea. Five acaricides having different mode of actions were selected for the present study. Fenazaquin10 EC, propargite 57 EC, hexythiazox 5.45 EC, spiromesifen 22.9SC and cyflumetofen 20SC were sprayed @ 100, 430, 15,96 and 125 g a.i. ha-1, respectively. Treated leaves were collected from the field and bioassay experiments were conducted in the laboratory. The results revealed that cyflumetofen 20 SC persisted for a longer duration (28 days) with the highest PT value (2347.24) whereas, propargite 57 EC persisted for a relatively short duration (22 days) with lesser PT values (1678.93). Higher LT50 values of 23.83 and 24.26 days were also observed in case of cyflumetofen 20 SC @ 125 g a.i. ha-1 during 1st and 2nd years of study, respectively. The lowest LT50 value was observed in propargite 57 EC @ 430 g a.i. ha-1. Spiromesifen 22.9 SC was found to be the second-best treatment and it showed the LT50 value 22.34 and 22.42 days during 1st and 2nd year of study, respectively. [ABSTRACT FROM AUTHOR]

Background: The pigeonpea eriophyid mite, Aceria cajani Chan., vector of sterility mosaic disease in pigeonpea, causes economic damage of up to 90% during the early stages of crop growth. The major element in deploying management practice is to know the population dynamics of the pest. Generally, the vectors of disease causing agents were managed with the synthetic chemical. So we have taken studies to know efficacy of insecticides and acaricides in its control on pigeonpea. Methods: The population dynamics of A. cajani Chan. was monitored in field plots from January 2021 to December 2021. For efficacy of insecticides and acaricides studies in control of A. cajani a completely randomized design was organized. Twelve treatments (insecticides/acaricides) were tested against A. cajani on pigeonpea [var. ICP 8863 (Shree Maruti]. Result: This study found that mite population reached a peak in the summer (March) and another peak in the post-monsoon period (October), whereas the lowest populations were recorded in winter (January). Correlation studies exhibited a significant positive correlation with both maximum and minimum temperature. The insecticide and acaricide trials on A. cajani found that all chemicals used were effective and entomopathogenic formulations were comparatively less effective. [ABSTRACT FROM AUTHOR]

Varroa destructor is a dangerous pest directly for beekeeping and indirectly for crops that require insect pollination. In recent years, the application of chemical pesticides has led to the occurrence of mite resistance and contamination of hive products. Plant extracts are considered as a suitable alternative to chemical acaricides for the Varroa mite control. Therefore, the present study aimed to investigate the acaricidal and insecticidal activity of extract of Prangos ferulacea plant against the Varroa mite and its host in the honey bee colonies in the climatic conditions of Kurdistan province from 2022 to 2024. The P. ferulacea plant was collected in June 2022 from different regions of Kurdistan province in the flowering stage, extracted and then its chemical compounds were identified using GC-MS. The present study was conducted in the form of a factorial experiment based on a completely random basic design with four treatments and seven replications. Before conducting the bioassay experiments, the experimental colonies were homogenized in terms of queen age, population (adults and brood), and honey storage. Also, the initial infestation rate of colonies with Varroa mites was evaluated for adult and brood. The results showed that the extract of 50% of P. ferulacea was relatively favorable acaricidal properties. So that, there was no significant difference with oxalic acid and Apistan treatments in terms of mite mortality percentage in the first time of spraying. Also, the result showed that the bee's mortality percentage was not more than 7% in any of the times of spraying with the 50% extract of the P. ferulacea, and there was observed a significant difference compared to the oxalic acid and Apistan treatments in terms of bee's mortality percentage (P<0.01). The queen superseding was not observed in any of the experimental treatments. According to the findings of the present research, the concentration of 50% of the extract P. ferulaceous can be suggested as a suitable alternative to synthetic acaricides and organic acids to control the Varroa mite in honey bee colonies. [ABSTRACT FROM AUTHOR]

Dermatophagoides farinae is a major source of allergens that are the cause of allergic diseases in humans. Methyl isoeugenol (MIE) is a naturally occurring compound in plants and its strong acaricidal toxicity has been established; however, the mechanism behind its acaricidal properties remains unclear. In this study, to investigate the action mechanism of MIE on D. farinae the isobaric tags for relative and absolute quantification (iTRAQ) proteomics method is used. Protein samples were extracted from D. farinae before and after 24 h of MIE treatment for iTRAQ technique analysis. Bioinformatics analysis revealed that most differentially expressed proteins were located in the cytoplasm, impacting cytoplasmic function. Additionally, Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses showed significant enrichment of the differential proteins in the cellular autophagy signalling pathway. The autophagy-related proteins Autophagy-Related Protein 3 (ATG3) and Cathepsin L (CTSL) were up-regulated, disrupting the autophagic process. We found that the main action mechanism of MIE against D. farinae might be cellular autophagy. The transcriptional validation of six differential proteins demonstrated consistent expression trends with the proteomics data. This study reveals the acaricidal mechanism of MIE for the first time and lays the foundation for further research on D. farinae control. [ABSTRACT FROM AUTHOR]

In order to obtain acaricides of pyrazole acrylonitrile with better acaricidal activity for mitecontrol, seventeen novel ester derivatives were synthesized via four steps of Blanc chloromethylation reaction, dehalogenation reaction, condensation reaction and esterification reaction using ethyl 1,3-dimethyl-1H-pyrazole-5-carboxylate as the starting material. Furthermore, their acaricidal activity against Tetranychus cinnabarinus was assessed by immersion test, and the mortality rate and lethal midrange concentration LC50 were calculated. The results show that the target compounds display excellent acaricidal activity against T. cinnabarinus, and compared with the commercial pesticide cyenopyrafen (LC50 = 0.61 mg/L), compounds 5q and 5k possess significantly higher acaricidal activity against T. cinnabarinus with LC50 values of 0.17 and 0.22 mg/L, respectively. [ABSTRACT FROM AUTHOR]

Background: The control and prevention of ticks and tick borne diseases (TBDs) is often difficult, since it is necessary to disrupt a complex transmission cycle, involving ticks and vertebrate hosts, which interact in a changing environment, driven by constant environmental and ecological changes. Our view is that factors driving the spread of R. microplus are complex and intrinsically interconnected, something that has often been ignored in control strategies. Results: The aim of this review is to analyze the importance of the epidemiological surveillance of ticks and tick-borne diseases (TTBDs) for Public Health, with the One Health approach; emphasizing the knowledge, importance, and distribution of TTBDs. Conclusions: The key points for surveillance, and raising the scope and limitations of surveillance programs, to delay the emergence of acaricide resistance, to reduce toxic residues in food for human consumption and to protect animal, human, and environmental health, from a One Health perspective will require calling producers, veterinarians, academics, pharmaceutical industry, and decision makers to join efforts in order to mitigate the effects of ticks and TBDs affecting the cattle industry in Mexico. [ABSTRACT FROM AUTHOR]

Background: Canine acaricides with rapid onset and sustained activity can reduce pathogen transmission risk and enhance pet owner experience. This randomized, complete block design, investigator-masked study compared the speed of kill of Amblyomma americanum provided by three monthly-use isoxazoline-containing products. Methods: Eight randomized beagles per group were treated (day 0), per label, with sarolaner (combined with moxidectin and pyrantel, Simparica Trio™), afoxolaner (NexGard™), or lotilaner (Credelio™), or remained untreated. Infestations with 50 adult A. americanum were conducted on days − 7, − 2, 21, and 28, and tick counts were performed on day − 5 (for blocking), and at 4, 8, 12, 24, 48, and 72 h following treatment and subsequent infestations. Efficacy calculations were based on geometric mean live tick counts. A linear mixed model was used for between-group comparisons. Results: On day 0, only lotilaner significantly reduced an A. americanum infestation by 12 h (43.3%; P = 0.002). Efficacy of lotilaner and afoxolaner at 24 h post-treatment was 95.3% and 97.6%, respectively, both significantly different from sarolaner (74%) (P = 0.002, P < 0.001, respectively). On day 21, at 12 h postinfestation, lotilaner efficacy (59.6%) was significantly different from sarolaner (0.0%) (P < 0.001) and afoxolaner (6.3%) (P < 0.001). At 24 h, lotilaner efficacy (97.4%) was significantly different (P < 0.001) from sarolaner and afoxolaner (13.6% and 14.9%, respectively). On day 28, at 12 h postinfestation, lotilaner efficacy (47.8%) was significantly different from sarolaner (17.1%) (P = 0.020) and afoxolaner (9.0%) (P = 0.006). At 24 h, lotilaner efficacy (92.3%) was significantly different from sarolaner 4.9% (P < 0.001) and afoxolaner (0.0%) (P < 0.001). Speed of kill for sarolaner and afoxolaner, but not lotilaner, significantly declined over the study period. Following reinfestation on day 28, neither sarolaner nor afoxolaner reached 90% efficacy by 48 h. By 72 h, sarolaner efficacy was 97.4% and afoxolaner efficacy was 86.3%. Only lotilaner achieved ≥ 90% efficacy by 24 h post-treatment and 24 h postinfestation on days 21 and 28. Time to ≥ 90% efficacy following new infestations consistently occurred 24–48 h earlier for lotilaner compared with sarolaner or afoxolaner. Conclusions: Credelio (lotilaner) has a more rapid onset of acaricidal activity against A. americanum than Simparica Trio (sarolaner-moxidectin-pyrantel) and NexGard (afoxolaner). Only lotilaner's speed of tick kill is sustained throughout the dosing period. [ABSTRACT FROM AUTHOR]

Background: Production of entomopathogenic fungi on a solid substrate, mostly on rice, is preferred by many producers due to its low technological requirements. Drying may be needed after fermentation to preserve the viability of the conidia until use. This study aimed to introduce some uncomplicated drying techniques and study their effectiveness in terms of drying time and extent, as well as their impact on the quantity of conidia produced and their biological activity. Four techniques were studied, i.e., condensing water vapor (by cooling), desiccant (using NaOH), air drying on a net, and air drying on a solid (impermeable) surface. Results: Condensing water vapor and desiccant techniques were the fastest and most efficient, resulting in the lowest moisture content, ranging between 12 and 13%. While drying on a solid surface was the slowest and resulted in the highest moisture content of 32.98%. All of the dried samples yielded a lower quantity of conidia compared to the fresh samples. Samples of condensing water vapor, desiccant, and net techniques yielded approximately a similar quantity of conidia, ranging between 74 and 71% of the yield of the fresh sample. The solid surface sample yielded the lowest quantity of conidia, representing 63.78% of the fresh sample yield. A bioassay test on the mite, Tetranychus urticae Koch (Acari: Tetranychidae), showed that conidia dried via condensing water vapor and desiccant techniques kept their pathogenicity similar to the fresh sample, while samples dried on a net and solid surface significantly lost part of their pathogenicity. Conclusion: The condensing water vapor and desiccant techniques were the most efficient regarding the time needed, conidia yield, and pathogenicity. Drying on a solid surface was the least effective regarding the same factors. [ABSTRACT FROM AUTHOR]

Background: Cucumber plants are susceptible to several economically damaging pests, including whiteflies, aphids, thrips and spider mites. This study aimed to evaluate the efficacy of two biological control programs, utilizing different releases of bio-agents, in comparison with chemical control method. The bio-agents used were the aphid parasitoid Aphelinus albipodus Hayat and Fatima (Hymenoptera: Aphelinidae), the green lacewing Chrysoperla carnea (Steph.) (Neuroptera: Chrysopidae) and the predatory mite Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae) in two release rates; low and high. Additionally, a chemical pesticides treatment was included for comparison in managing the pests in cucumber greenhouses during the winter seasons of 2022 and 2023, in Egypt. Abundances of whitefly, aphids, thrips and spider mites were recorded weekly throughout the study. Results: The aphid population in the greenhouse with high release rate (BIO 2) showed the highest reduction, with percentages of 84.55 and 89.88% in 2022 and 2023, respectively. Both greenhouse with low release rate (BIO 1) and BIO 2 exhibited significant reductions in the whitefly population, with proportions of 71.31 and 72.01% in 2022, and 82.05 and 85.94% in 2023, respectively. The thrips population also experienced notable reductions in both BIO 1 and BIO 2 greenhouses, with percentages of 72.08 and 75.71% in 2022, and 59.93 and 61.38% in 2023, respectively. However, the pesticide treatment demonstrated the lowest reduction in populations of aphids, whitefly and thrips in both seasons. Nevertheless, in all treatments in the two evaluated seasons, the high release rate of the predatory mite, P. persimilis (15 individuals/m2), proved to be highly effective in maintaining the mite populations below the economic threshold level. However, the population density of the two-spotted spider mite, Tetranychus urticae Koch. (Acari: Tetranychidae), increased in the pesticide-treated greenhouse, indicating the development of resistance to pesticides. Although the tested programs resulted in similar yields, the biological control approach offered the advantage of pesticide-free produce and reduced production costs. Conclusion: For pest management in cucumber growing in greenhouses during winter, it is recommended to use biological control agents at a low release rate at the early occurrence of pests. This approach can help minimize pest populations effectively. [ABSTRACT FROM AUTHOR]

Ticks are ectoparasites belonging to the phylum Arachnida infesting humans and animals. Besides their parasitic role, ticks also spread multiple bacterial, viral, and parasitic diseases because of their vector role. Hyalomma is a major genus of ticks containing species of zoonotic and pathogenic significance. Control of the ticks is the primary importance, but chemical acaricides are being avoided because of resistance and one health-related issue. In this study, acaricidal and repellent activities of the ethanolic and ethyl acetate extracts of Tobacco (Nicotiana tabacum) have been evaluated against the ticks of Hyalomma genus. Each extract was serially diluted to have 1.25, 2.5, 5, and 10% concentrations. The parameters taken were adult mortality, larval mortality, egg hatchability and product effectiveness. The results suggested that the ethyl acetate and ethanolic extracts had statistically comparable (P>0.05) effects on adult mortality (tick immersion), larval mortality (larval immersion test), egg hatchability and tick repellency parameters. This research also revealed that extracts of N. tabacum were also comparable to (P>0.05) standard medicated control at the highest concentrations. Ethanolic and ethyl acetate extracts had significantly (P<0.05) different acaricidal effects from the blank control at 10% concentration. This research suggests that the N. tabacum can be used as an acaricidal and tick-repellent agent. [ABSTRACT FROM AUTHOR]

Eriophyid mites, minute arachnids within the family Eriophyidae, pose significant threats to fruit crops globally, leading to substantial economic losses in agriculture. This comprehensive review aims to elucidate the intricate biology, ecology, molecular aspects, and innovative control strategies of these pervasive pests. Eriophyid mites exhibit a complex life cycle and reproductive strategy, with their habitat preferences and distribution heavily influenced by environmental factors and host-plant interactions. Advances in molecular biology have provided more profound insights into their genetics and interactions at the molecular level, revealing crucial information for developing targeted pest management strategies. Control strategies for eriophyid mites encompass chemical methods, such as applying acaricides and understanding resistance mechanisms, as well as biological control using natural predators and parasitoids. Cultural and physical control methods, including crop rotation and mechanical removal, play vital roles in integrated pest management (IPM). Emerging approaches like RNA interference (RNAi) and semiochemical-based controls offer promising alternatives for sustainable pest management. This review underscores the importance of a multifaceted approach to effectively manage eriophyid mite infestations, integrating traditional and novel strategies. Future research should focus on overcoming current challenges, enhancing the efficacy of control methods, and further exploring the molecular mechanisms underlying mite-plant interactions. [ABSTRACT FROM AUTHOR]

Background and Objective: The use of pesticides poses serious risks to the health of living organisms. Knowing the type and amount of pesticide use can provide a good information base for managing potential risks from pesticide consumption. This study was carried out with the main objective of determining the types and amounts of pesticides used on agricultural land in East Azarbaijan Province in 2021. Materials and Methods: Information about the pesticides have been gathered and analyzed by referring to the Agricultural Jihad Organization and other relevant authorities. Calculations related to the amount of pesticides used per unit area were made using the total area of agricultural lands in the province. Results: Considering the frequency, 403 kinds of pesticides are used in the following order: Herbicides > Insecticides > Fungicides > Acaricides > Others > Disinfectants. Consdidering total consumption of 2873730 kg pesticides, the order based on the amount is: Insecticides > Herbicide > Fungicides > Miscellaneous > Acaricides and Disinfectants based on the amount. The total ratio of pesticides used to pesticides distributed through the official (government) channel is 2.51. The minimum, maximum, and mean consumption values in counties are 0.4, 21.4, and 4.21 ± 5.33 kg/ha, respectively, and for province is 2.38 kg/ha. There is a correlation between the amount of pesticide applied and the number of farmers and traders. Conclusion: The consumption of pesticides in the province is higher than the world average. Appropriate management of pesticides is required from the viewpoints of environment and health protection. [ABSTRACT FROM AUTHOR]

Rhipicephalus microplus is the parasitic species that causes the most damage to Mexican and global livestock due to direct and indirect losses, such as the increase in multidrug resistance and cross-resistance. Currently, there are few studies on resistance to macrocyclic lactones in Mexico, most of them in the south. This study aimed to evaluate the status of ivermectin resistance in R. microplus in northeastern Mexico and its associated risk factors. A total of 20 populations of Rhipicephalus microplus were collected in the states of Veracruz, Nuevo León, Tamaulipas, and San Luis Potosí, and they were analyzed with the larval immersion test. Mortality data were subjected to a Probit analysis, estimating lethal concentrations (LC) of 50 % and 99 % and their respective 95 % confidence intervals (95 % CI), and to determine possible risk factors, a multivariate analysis and 2 x 2 contingency tables were performed for the exposure variables, with a 95 % confidence interval, and a binomial logistic regression model for those variables with a P=0.05. Eighty (80) percent of the analyzed populations showed resistance with ranges of RR50= 2.07-11.14 and RR99= 3.03-47.93 (P=0.05), and through the binomial logistic regression, it was observed that the variable of frequency of treatments obtained a P=0.0134, a result that proved to be significant. [ABSTRACT FROM AUTHOR]

The two-spotted spider mite, T. urticae, is a significant global agricultural pest. It has become highly resistant to numerous pesticides and is incredibly polyphagous. Herein, five pesticides were tested for their ability to control T. urticae: sulfoxaflor + spinetoram, emamectin benzoate, thiamethoxam, spirodiclofen, and etoxazole in the Manfalout and Qusia districts in Assiut Governorate, Egypt during the 2021 and 2022 seasons. The results revealed that all pesticides were effective on T. urticae based on the mean reduction percentage (the ranges were 62.75%- 68.00%) during the 2021 season on cucumber plants in Manflout district. Further, the most potent pesticides in Qusia district were thiamethoxam, spirodiclofen, and emamectin benzoate and the mean reduction percentage were 63.39%, 58.31%, and 56.75%, respectively during the 2021 season. In 2022 season, the most toxic pesticides were thiamethoxam, etoxazole, and emamectin benzoate in Manflout district whereas, in Qusia district, the most powerful pesticides were spirodiclofen, etoxazole, and emamectin benzoate and the mean reduction percentage were 60.00%, 57.67%, and 56.75%, respectively. The tested pesticides are an effective tool that can be used in integrated pest management (IPM) programs against T. urticae on cucumber. [ABSTRACT FROM AUTHOR]

Simple Summary: Working in two native berry crops, we trapped honey bee pollen as foragers entered the hive. We then obtained grower records of the pesticides that were applied on the farm. We analyzed the pesticide residues in each pollen sample and established a baseline for real-world exposure levels and combinations to contaminated pollen. Between the two crops, the number of pesticides, total residue concentrations, and risk of exposure varied. The blueberry residue array was dominated by fungicides and miticides and cranberry was dominated by insecticides and herbicides. In most cases, pesticide residue concentrations were of low risk (low risk quotient) to honey bees in these crops. We documented that there were many residues that foragers would have picked up "off-farm." The reports from growers regarding their pesticide application dates allowed estimates of field decay rates of several common pesticides. Some compounds were detected in pollen many days after application. Taken together, our findings may be key to future work aimed at reducing risk to bees. A pesticide exposure baseline for honey bees was compiled for two New England cropping systems, the native North American plant species consisting of lowbush blueberry (Vaccinium angustifolium Aiton) and cranberry (Vaccinium macrocarpon Aiton). More unique pesticide compounds were applied in blueberry than cranberry, but the numbers of pesticides discovered in trapped honey bee pollen were similar between the two crop systems. Not all pesticides found in pollen were the result of the applications reported by growers of either crop. When comparing residues, number of pesticides detected, total concentration, and risk quotient varied between the two crops. Also, blueberry was dominated by fungicides and miticides (varroacides) and cranberry was dominated by insecticides and herbicides. When comparing reported grower applications that were matched with detection in residues, the proportion of pesticide numbers, concentrations, and risk quotients varied by crop system and pesticide class. In most cases, pesticide residue concentrations were of low risk (low risk quotient) to honey bees in these crops. Estimation of decay rates of some of the most common pesticide residues under field conditions could aid growers in selection of less persistent compounds, together with safe application dates, prior to bringing in honey bees for pollination. [ABSTRACT FROM AUTHOR]

Context: Zeolites have attracted attention for their potential in adsorbing environmental contaminants. However, contaminants, such as acaricides used extensively in livestock production to control ticks and mites, have received limited exploration regarding their adsorption onto zeolite surfaces. This study aimed to identify the most appropriate zeolite frameworks for the adsorption of acaricide residues, deduce the mechanism underlying the adsorption process, and evaluate the impact of surface modification on the adsorption capabilities of zeolites. Methods: Grand Canonical Monte Carlo (GCMC) was used to screen the entire zeolite database to analyze their adsorption properties, where the cloverite zeolite framework (CLO) exhibits the highest adsorption capacity (percentage weight, 54%). Machine learning was employed to rank structural feature importance on adsorption. Density and helium void fraction appeared to be the most important structural features. Thus, engineering these features is of utmost significance in harvesting the desired acaricides. The second step involved engineering the structural and electronic properties of the shortlisted zeolite frameworks via cation substitution with suitable atoms. DFT calculations involving natural bond orbital (NBO) analysis and quantum theory of atoms in molecules (QTAIM) have been done to understand the influence of cation substitution on the electronic structure. [ABSTRACT FROM AUTHOR]

The European Food Safety Authority (EFSA) was asked by the European Commission to provide scientific assistance with respect to the risk assessment for an active substance in light of confirmatory information requested following approval in accordance with Article 6(1) of Directive 91/414/EEC and Article 6(f) of Regulation (EC) No 1107/2009. In this context EFSA's scientific views on the specific points raised during the commenting phase conducted with Member States, the applicant and EFSA on the confirmatory information and their use in the risk assessment for etoxazole are presented. The current report summarises the outcome of the consultation process organised by the rapporteur Member State Greece and presents EFSA's scientific views and conclusions on the individual comments received. [ABSTRACT FROM AUTHOR]

The two-spotted spider mite, Tetranychus urticae (Koch, 1836) (Acari: Tetranychidae) causes significant problems in cotton fields. The pest has developed resistance to abamectin, which is used intensely against spider mite populations. A discriminating dose was applied to T. urticae populations collected from Aydın, Adana, Şanlıurfa, and Diyarbakır provinces between 2019 and 2021, where there is significant cotton production and intensive acaricide applications. Populations with a mortality rate of less than 80% at the discriminating dose applied to field populations were included in the bioassay study. Then, the 10 most resistant populations were determined based on their LC50 and LC90 values. It was observed that there was high resistance (HR) in two T. urticae populations collected from Diyarbakır (DIY28 and DIY2) with LC50 values of 24.5 and 33.81 mg L-1, respectively 113 and 156-fold and one population collected from the province of Aydın (AYD4) LC50 value of 23.5 mg L-1 and 109-fold. As a result of the comparisons with a susceptible population in biochemical studies, it was determined that the carboxylesterase (CarE) enzyme of these populations (except for SAN6, SAN7, SAN8, ADA9, and ADA11) had more than 2-fold higher activity compared to the glutathione enzyme (GST), and they were in statistically different groups. When the GST enzyme activities were examined, it was found that the enzyme activities were generally low, except for the ADA11 and ADA16 populations (3.73 and 2.3-fold). In terms of the target site resistance, it was observed that there was no target site mutation (G314D and I321T-G326E) in the glutamate-gated chloride channels (Units GluCl 1 and 3) in these highest 10 resistant populations. It can be said that the resistance levels determined for abamectin from the obtained populations were determined to be low. In brief, out of the total 44 populations brought in and tested, only 30 populations were considered resistant with a mortality rate below 80% after the applied discriminating dose. It was determined that 6.8% of these 30 populations had HR, 31.8% had medium resistance (MR), and 29.5% had low resistance (LR). When examining by regions, it was found that high resistance populations were more prevalent in Diyarbakır and Aydın (15.4% and 10%, respectively) provinces, while the highest percentage of MR populations was found in Şanlıurfa, at 90%. Abamectin still acts as an effective acaricide. However, it is recommended to use acaricides with different modes of action to prevent possible emergence of resistance cases. [ABSTRACT FROM AUTHOR]

Background: Green bean, Phaseolus vulgaris L. (Fam.: Leguminosae) is a widely consumed grain legume prized for its edible seeds and pods. It is susceptible to infestations with various pests as insects and mites throughout the growing season. In this study, the efficacy of the predatory species, Chrysoperla carnea (Stephens), Phytoseiulus persimilis Athias-Henriot and the entomopathogenic fungus (EPF) Metarhizium anisopliae (Hypocreales: Clavicipitaceae), as well as conventional pesticides, Mospilan and Vertimec, were evaluated against the most important pests, mainly the whitefly, Bemisia tabaci (Genn.) and the two-spotted spider mite, Tetranychus urticae Koch, infesting the green beans cultivated at two locations Giza and El-Menoufia Governorates in Egypt. Results: The findings demonstrate that treatments using C. carnea and M. anisopliae effectively reduced the whitefly population, while pesticide treatments were comparatively less effective. In the Giza plots, at the end of the experiments, the use of both M. anisopliae and C. carnea showed high reductions in whitefly population (85.57 and 84.87%), respectively, while in El-Menoufia, C. carnea (97.74%) was the most effective treatment followed by M. anisopliae (90.32%). Pesticide treatment in this case yielded a reduction rate of (22.76 and 59.67%) in Giza and El-Menoufia plots, respectively. However, for spider mite control, P. persimilis proved to be the most effective treatment in Giza and El-Menoufia plots, reducing the spider mite population to 98.44 and 96.14%, respectively. Metarhizium anisopliae treatment also displayed moderate effectiveness, with reduction rates of 75.62 and 75.37% in Giza and El-Menoufia plots, respectively. In comparison, pesticide treatment showed low effectiveness, with reduction rates of only 23.92 and 53.16% in the two locations, respectively. Conclusion: Applications of the predator, C. carnea and the EPF, M. anisopliae were highly effective in reducing the population of whitefly, while the predator mite P. persimilis proved to be the most effective for controlling the spider mites. Overall, the study suggests that biocontrol agents, such as the predators and the EPF, can be considered as alternatives to synthetic chemical pesticides for controlling pests infesting green beans. [ABSTRACT FROM AUTHOR]

Background: Among the Citrus species, lemon (Citrus limon Burm f.) is one of the most affected by the two-spotted spider mite (Tetranychus urticae Koch). Moreover, chemical control is hampered by the mite's ability to develop genetic resistance against acaricides. In this context, the identification of the genetic basis of the host resistance could represent a sustainable strategy for spider mite control. In the present study, a marker-trait association analysis was performed on a lemon population employing an association mapping approach. An inter-specific full-sib population composed of 109 accessions was phenotyped through a detached-leaf assays performed in modified Huffaker cells. Those individuals, complemented with two inter-specific segregating populations, were genotyped using a target-sequencing approach called SPET (Single Primer Enrichment Technology), the resulting SNPs were employed for the generation of an integrated genetic map. Results: The percentage of damaged area in the full-sib population showed a quantitative distribution with values ranging from 0.36 to 9.67%. A total of 47,298 SNPs were selected for an association mapping study and a significant marker linked with resistance to spider mite was detected on linkage group 5. In silico gene annotation of the QTL interval enabled the detection of 13 genes involved in immune response to biotic and abiotic stress. Gene expression analysis showed an over expression of the gene encoding for the ethylene-responsive transcription factor ERF098-like, already characterized in Arabidopsis and in rice for its involvement in defense response. Conclusion: The identification of a molecular marker linked to the resistance to spider mite attack can pave the way for the development of marker-assisted breeding plan for the development of novel selection coupling favorable agronomical traits (e.g. fruit quality, yield) with a higher resistance toward the mite. [ABSTRACT FROM AUTHOR]

The generalist predator Orius similis plays a crucial role in controlling the pests Frankliniella occidentalis (Pergande) and Tetranychus urticae Koch. To assess the effectiveness of O. similis in controlling these pests in bean field, we conducted field surveys and used DNA molecular analysis to quantitatively measure the levels of predation on each prey. Field surveys conducted from June 18 to August 7, 2021, showed a linear increase in the population densities of O. similis, F. occidentalis, and T. urticae. The population density of F. occidentalis and T. urticae peaked on July 16, whereas that of O. similis peaked on July 23. The highest positive rate for F. occidentalis and T. urticae was observed on July 23 and 16, respectively. The positive detection rate to F. occidentalis was significantly higher than that of T. urticae (t = 7.659, df = 14, P < 0.0001). The DNA half-lives of F. occidentalis and T. urticae were estimated at 4.44 and 2.60 h, respectively, based on the positive detection rates of both preys during the digestion time in O. similis. These results suggest that molecular intestinal content analysis can be effectively used to quantitatively evaluate the control effect of O. similis on F. occidentalis and T. urticae. [ABSTRACT FROM AUTHOR]

Spider mites are some of the most important agricultural pests worldwide, jeopardizing maize production across many continents. However, mechanisms of resistance to spider mite in maize remain unclear. Here, we report data from resistant and susceptible maize varieties, Jingke968 and Xianyu335 along with their parental lines, and investigate their responses to Tetranychus urticae (Acari: Tetranychidae). A significantly lower female adult mite population and total mite numbers were recorded in the resistant variety, Jingke968, compared to Xianyu335. Similarly, mite fecundity on Jingke968 was substantially lower compared to Xianyu335, which could be associated with its highly resistant parental line Jing92. Stomatal dimensions also showed a close correlation with the fitness of spider mites on the two maize varieties and four parental lines. Tetranychus urticae population numbers under field conditions showed lower mite densities (numbers per plant) in Jingke968 and Jing92 (75% and 89% lower, respectively) than the most sensitive line PH6WC, hinting toward a high level of resistance to spider mites in these maize lines. Our study provides new insights for mechanisms of physical defense to spider mites in maize and contributed to the basis for pest control and breeding of maize varieties. [ABSTRACT FROM AUTHOR]

Simple Summary: Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) is one of the most potent predaceous mites in biological pest management, feeding on phytophagous mites, pollens, and plant exudates. Tetranychus urticae Koch (Acari: Tetranychidae), a global mite, infects many field crops, fruit orchards, and ornamental plants by reducing photosynthesis and feeding on plant cells. This study reveals that the functional response estimates of A. swirskii vary with temperature (14, 18, 22, 26, 30, and 34 ± 1 °C) and prey density. We found that the highest searching efficiency was at 26 °C and that the lowest was at 14 °C. The handling time for each prey item also varies with temperature and prey density. The functional response curves align with the type II functional response model, showing the inverse dependence of temperature and prey density. The predation curves for A. swirskii show a significant difference in the mean numbers of T. urticae consumed at different prey densities and temperatures. This study highlights the relationship between A. swirskii and T. urticae and the importance of temperature and prey density in natural enemies' activities. The findings can help predict A. swirskii behavior and its effectiveness in controlling T. urticae populations. Amblyseius swirskii are predaceous mites that feed on phytophagous mites, pollens, and plant exudates and are known as one of the most potent biological pest management agents. Tetranychus urticae is a global mite that is difficult to manage because of its high population growth rates, necessitating alternative management measures like biological control. Regarding the functional response, the effects of temperature and prey density are some of the essential behaviors of natural enemies. This study investigates the effect of varying temperatures and prey densities on A. swirskii, a biological control agent for T. urticae. The present results demonstrated the change in the functional response estimates when A. swirskii was reared at various temperatures and different prey densities. The results of the estimates regarding the searching efficiency (a′) showed the highest value (a′ = 0.919) at 26 °C and the lowest value (a′ = 0.751) at 14 °C. The handling time per prey item (Th) for the predatory mites changed with the temperature and prey density, showing the shortest handling time at 26 °C (Th = 0.005) and the highest value at 14 °C (Th = 0.015). The functional response curves matched the type II functional response model, demonstrating the inverse dependence of temperatures and prey density with a positive quadratic coefficient. The predation curves for A. swirskii showed a significant difference between the mean numbers of T. urticae consumed at various prey densities and temperatures, illustrating a relationship between A. swirskii and T. urticae. Therefore, the results of this research may be utilized to forecast the behavior of A. swirskii and its usefulness in controlling T. urticae populations. [ABSTRACT FROM AUTHOR]

Simple Summary: Increasing honey bee resilience against the parasitic mite Varroa destructor, while respecting sustainability, may be achieved by enriching natural mite resistance traits in the breeding population. Some of these traits are linked to specific variants in the honey bee genome, which can be pinpointed and characterized with high-throughput molecular lab tests. Breeding by focusing on these genomic variants is thus more efficient and less time-consuming. However, when evaluating the link between a specific varroa resistance trait outcome and its associated variants in the genome, different contributions of the variants may be observed between honey bee races. It is hypothesized that these observations evolve from different linkages between the trait-causing genes and the genomic variants. Therefore, we evaluated the presence of genomic variants associated with a varroa resistance trait in different honey bee samples across the European continent. We observed significant differences in the presence of the genomic variants in the considered honey bee races, which underpin our hypothesis of linkage dissimilarities. This study shows that determining the honey bee race prior to using the genomic variants associated with varroa resistance for selective breeding is of utmost importance. Implementation of marker-assisted selection (MAS) in modern beekeeping would improve sustainability, especially in breeding programs aiming for resilience against the parasitic mite Varroa destructor. Selecting honey bee colonies for natural resistance traits, such as brood-intrinsic suppression of varroa mite reproduction, reduces the use of chemical acaricides while respecting local adaptation. In 2019, eight genomic variants associated with varroa non-reproduction in drone brood were discovered in a single colony from the Amsterdam Water Dune population in the Netherlands. Recently, a new study tested the applicability of these eight genetic variants for the same phenotype on a population-wide scale in Flanders, Belgium. As the properties of some variants varied between the two studies, one hypothesized that the difference in genetic ancestry of the sampled colonies may underly these contribution shifts. In order to frame this, we determined the allele frequencies of the eight genetic variants in more than 360 Apis mellifera colonies across the European continent and found that variant type allele frequencies of these variants are primarily related to the A. mellifera subspecies or phylogenetic honey bee lineage. Our results confirm that population-specific genetic markers should always be evaluated in a new population prior to using them in MAS programs. [ABSTRACT FROM AUTHOR]

Simple Summary: Tetranychus truncatus (Acari: Tetranychidae) is the dominant pest on many crops in China. The resistant strain cultivated by pyridaben in our laboratory showed higher adaptability to high temperature than the susceptible strain. Antioxidant enzymes can reduce the damage of reactive oxygen species (ROS) caused by high temperature. Therefore, the antioxidant enzyme genes of T. truncatus were screened, and their biological information was analyzed. The expression patterns of antioxidant enzyme genes in two strains of T. truncatus under high temperature stress were determined by RT-qPCR method, and their functions were verified by RNA interference (RNAi) technology. The experimental results provide a theoretical basis for understanding the occurrence of agricultural mites under the background of climate warming and applying gene regulation technology to control T. truncatus in the future. Tetranychus truncatus (Acari: Tetranychidae) has caused serious economic losses on some crops (soybean, corn, and cotton) in China, and has developed resistance to most acaricides. Our laboratory study found that T. truncatus was resistant to pyridaben and also adapted to high temperature (34–40 °C). High temperature stress may cause arthropods to produce a large amount of reactive oxygen species (ROS), causing oxidative damage. Antioxidant enzymes, as the main antioxidants, can reduce the damage caused by excessive ROS in arthropods. In order to study the adaptation mechanism of the pyridaben-resistant strain of T. truncatus to high temperature and the role of antioxidant enzyme genes under high temperature stress, four antioxidant enzyme genes, TtSOD, TtPOD3, TtPOD4, and TtGSTs2, were screened according to the transcriptome sequencing data of pyridaben-susceptible and -resistant strains in T. truncatus. Firstly, the phylogeny and structure analyses of these four genes were carried out. Then, real-time quantitative PCR (RT-qPCR) technology was used to analyze the gene expression patterns of antioxidant enzymes in two strains of T. truncatus at three different high temperature ranges (34 °C, 38 °C, and 42 °C). The results showed that the expression levels of four antioxidant enzyme genes of two strains of T. truncatus were induced by high temperature stress, and the expression levels of antioxidant enzyme genes were significantly different in each development state. The gene expression of antioxidant enzyme genes in resistant strains at the adult stage was significantly higher than that in susceptible strains. After the TtSOD and TtPOD4 genes of adult mites of the resistant strain were silenced by RNA interference (RNAi) technology, the mortality rate of mites with TtPOD4 gene silencing reached 41.11% after 96 h at 34 °C, which was significantly higher than that of the control and TtSOD gene silencing. It has been confirmed that the TtPOD4 gene plays a key role in the adaptation of pyridaben-resistant strain of T. truncatus to high temperature. It lays a theoretical foundation for revealing the thermal adaptation mechanism of T. truncatus. [ABSTRACT FROM AUTHOR]

Environmental factors, such as photoperiod, can play an important role in the development of mites. The influence of photoperiod (L:D = 4:20, 8:16, 12:12, 16:8 and 20:4) on the development and population parameters of the predatory mite, Phytoseiulus persimilis Athias-Henriot fed on two-spotted spider mite, Tetranychus urticae Koch was examined under laboratory conditions. Pre-adult development decreased with increasing photoperiod until 12 h, after which the development period progressively increased. Longevity of both sexes demonstrated significant differences throughout photoperiods, with the longest at 20:4 L:D and the shortest at 8:16 L:D. The highest value of mean total fecundity was 13.62 egg/female at 12:12 L:D photoperiod. The net reproductive rate (R0), the intrinsic rate of increase (r) and the finite rate of increase (λ), showed the highest value at 12:12 L:D. The R0, r and λ for P. persimilis increased with increasing photoperiod from 4:20 to 12:12 L:D, but decreased sharply at the 16:8 and 20:4 L:D treatments. Our findings indicate that photoperiod has a significant role in advancing the rate of development, survival rate, and reproduction for commercial production of P. persimilis, with a 12:12 photoperiod length recognized as the ideal period for commercial production in culture. [ABSTRACT FROM AUTHOR]

The application of tick control strategies on tropical dairy cattle strongly relies on farmers' uptake, knowledge, and perceptions of the efficacy of control measures. This study aims to identify common and uncommon tick control practices employed by dairy farmers in subtropical areas of Ecuador and associate them with the presence of infestation and acaricide resistance. Data were collected through a cross-sectional survey and participatory meetings. Multiple correspondence analysis was used to explore the association between management variables and the level of tick infestation and resistance. It was determined that the main method of acaricide control is still chemical, mainly using spray baths. Generally, when this form of application is used, acaricides are overdosed, in contrast to the pour-on method with underdosage. Among the measures farmers adopt when chemical treatment has failed is to use overdoses of products, mix different acaricides, and use focused treatments (wipe cloth) with irritant substances. The absence of a high level of infestation was related to acaricide dips every 3–4 weeks and the use of intensive grazing. On the other hand, the high infestation was related to the use of organophosphates, wipe cloth application, and the report of tick-borne diseases (TBDs). A small group of farmers have good knowledge and seek alternatives to chemical control, experimenting with biological controls, herbal extracts, manual tick removal, and paddock control. Additionally, farmers reported the presence of TBDs (47%) and the presence of animals poisoned by acaricides (6%), which died in 75% of those cases. Farmers frequently mentioned that tick infestation induces milk drop production and weight loss and is associated with the presence of TBDs. This information is crucial to improve tick control management in Ecuador, particularly through implementing practices that mitigate resistance to acaricides and ensure long-term solutions that help maintain the efficacy of tick control treatments. [ABSTRACT FROM AUTHOR]