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The lacewing, Chrysoperla sinica Tjeder, as an important insect predator, plays an important role in biological control. In this study, exposure of the lacewing larvae to sublethal concentrations (LC1 and LC10) of lambda-cyhalothrin (λCy) inhibited the expression of the CsVg gene, decreased vitellogenin and vitellin content, affected ovogenesis and ovarian development, as well as significantly reduced oviposition and egg hatching in female adults. Further investigations indicated that the sublethal concentrations of λCy decreased juvenile hormone (JH) and 20-hydroxyecdysone (20E) titers in female adults during oviposition peak period, led to significant decrease in the activities and gene expression of key enzymes involved in their synthetic pathways. They also inhibited the expressions of the JH receptor gene, methoprenetolerant (Met), downstream transcription factors, krüppel homolog 1 (Kr-h1) in JH signaling and Broad-Complex (Br-C) in 20E signaling, specifically during oviposition peak period in female adults. Offsprings consecutively exposed to sublethal concentration of λCy exhibited hereditary and accumulative effects of hormone-related gene expression in this lacewing. In conclusion, this study demonstrates that sublethal concentrations (LC1 and LC10) of λCy causes hormonal signaling malfunction in C. sinica, resulting in the down-regulation of CsVg, which affect ovarian development and ovogenesis, and ultimately lead to severe decrease in fecundity. [ABSTRACT FROM AUTHOR]

The red palm weevil (RPW), Rhynchophorus ferrugineus Olivier, is a devastating insect-pest of 29 plants including date palm. It feeds inside the tree bark thus it is difficult to manage using insecticides. Only a few insecticides have been found effective against RPW. Among these insecticide, emamectin benzoate (EMB) is widely used. This insecticide can pose threat human and environmental health as it is used in the form of tree injection. Thus, keeping in view its possible, its sublethal effect on RPW was studied using Age-stage, two sex life table. Life table parameters of the progeny of exposed larvae to LC10, LC25, and LC50 of EMB were computed. Statistically higher fecundity (161.12 per female) was observed in control treatment, while less fecundity was observed in LC50 treatment. Significantly higher values for intrinsic rate of increase (r), finite rate of increase (λ), and net reproductive rate (Ro) (0.0376, 1.0383, and 67.13 per day, respectively) were recorded for the control treatment. Contrarily, lower values for r, Ro, and λ i.e. 0.0318, 23.82, and 1.0324 per day, respectively were recorded in the LC50 treatment. Decreased population parameters suggest that EMB can be successfully used in for the management of RPW. [ABSTRACT FROM AUTHOR]

The fall armyworm (FAW, Spodoptera frugiperda J. E. Smith), is a highly invasive pest causing significant crop yield losses. Chlorfenapyr has been widely utilized in China to control FAW. This study investigated the sublethal and transgenerational effects of chlorfenapyr on FAW to enhance its appropriate utilization. LC10 and LC20 values of chlorfenapyr were estimated to 7.47 and 12.08 μg/g after a 72-hour exposure, respectively. Low chlorfenapyr concentrations extended the duration of larval stage and pre-oviposition period, reducing larvae body weight, pupation rate and eclosion rate in both the F0 and F1 generations. Additionally, such exposure decreased the F0 generation's mating rate, fecundity, and egg hatching rate. The feeding indicators in third instar larvae from the F0 generation, including relative growth rate (RGR), efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD), and relative consumption rate (RCR), exhibited significant decrease compared to the control group, while approximate digestibility (AD) was higher. Larvae exposed to LC10 or LC20 exhibited elevated carboxylesterases (CarEs), cytochrome P-450s (P450s), and glutathione S-transferases (GSTs) activities from 12 to 24 hours' exposure, Notably, GSTs activity was higher at 6-hours compared to the control group, while CarEs and P450s activities significantly decreased. LC20 adversely affected long-term life table parameters of the F1 generation, including intrinsic rate of increase (r), the finite rate of increase (λ), and the net reproductive rate (R0). These findings demonstrate that sublethal effects of chlorfenapyr can impair FAW growth and development, impacting the population dynamics of the F1 generation. [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]

As an important pest on winter wheat, Rhopalosiphum padi (L.) causes damage to the wheat yield by sucking plant nutrients, transmitting plant viruses and producing mildew. R. padi has been reported to develop resistance to pyrethroids and neonicotinoids. To explore potential alternative approaches for R. padi control, the activity of 10 botanical insecticides was evaluated. Results suggested that the toxicity of rotenone and pyrethrins to R. padi were the highest and near to the commonly used chemical insecticides. When exposed to the low-lethal concentrations (LC10, LC30) of rotenone or pyrethrins for 24 h, the lifespan and fecundity of adults in F0 generation decreased significantly compared to control. The negative effect could also be observed in the F1 generation, including the decreased average offspring, longevity of adult, and prolonged nymph period. The population parameters in F1 generation of R. padi were also inhibited by exposing to the low-lethal concentrations of rotenone or pyrethrins, including the decreased net reproductive rate, intrinsic rate of natural increase, finite rate of population increase, and gross reproduction rate. Co-toxocity factor results showed that mixtures of rotenone and thiamethoxam, pyrethrins and thiamethoxam showed synergistic effect. Our work suggested that rotenone and pyrethrins showed negative effect on the population growth under low-lethal concentrations. They are suitable for R. padi control as foliar spraying without causing population resurgence. [ABSTRACT FROM AUTHOR]

Background: The widespread use of insecticide-treated nets (ITNs) has significantly contributed to the reduction in malaria cases and deaths observed across Africa. Unfortunately, this control strategy is threatened by the rapid spread of pyrethroid resistance in malaria vectors. Dual-active-ingredient insecticidal nets are now available to mitigate the impact of pyrethroid resistance. To facilitate evidence-based decisions regarding product selection in specific use settings, data are needed on the efficacy of these different nets against local mosquito populations. Methods: Two experimental hut trials were performed in Za-Kpota, southern Benin in 2021 to evaluate the performance of Interceptor G2 (BASF), Royal Guard (Disease Control Technologies) and PermaNet 3.0 (Vestergaard Frandsen), all dual-active-ingredient bednets, in comparison to untreated or standard pyrethroid-treated bednets, against free-flying wild Anopheles gambiae mosquitoes. The performance of some of these next-generation nets was compared to the same type of nets that have been in use for up to 2 years. Mosquitoes collected in the huts were followed up after exposure to assess the sublethal effects of treatments on certain life-history traits. Results: The predominant species in the study site was Anopheles gambiae sensu stricto (An. gambiae s.s.). Both Anopheles coluzzii and An. gambiae s.s. were resistant to pyrethroids (deltamethrin susceptibility was restored by piperonyl butoxide pre-exposure). In the experimental hut trials, the highest blood-feeding inhibition (5.56%) was recorded for the Royal Guard net, relative to the standard PermaNet 2.0 net (44.44% inhibition). The highest 72-h mortality rate (90.11%) was recorded for the Interceptor G2 net compared to the PermaNet 2.0 net (56.04%). After exposure, the risk of death of An. gambiae sensu lato (An. gambiae s.l.) was 6.5-fold higher with the Interceptor G2 net and 4.4-fold higher with the PermaNet 3.0 net compared to the respective untreated net. Lower mosquito mortality was recorded with an aged Interceptor G2 net compared to a new Interceptor G2 net. Oviposition rates were lower in mosquitoes collected from huts containing ITNs compared to those of untreated controls. None of the mosquitoes collected from huts equipped with Royal Guard nets laid any eggs. Conclusions: The Royal Guard and Interceptor G2 nets showed a potential to significantly improve the control of malaria-transmitting vectors. However, the PermaNet 3.0 net remains effective in pyrethroid-resistant areas. [ABSTRACT FROM AUTHOR]

Agricultural intensification has been identified as one of the key causes of global insect biodiversity losses. These losses have been further linked to the widespread use of agrochemicals associated with modern agricultural practices. Many of these chemicals are known to have negative sublethal effects on commercial pollinators, such as managed honeybees and bumblebees, but less is known about the impacts on wild bees. Laboratory‐based studies with commercial pollinators have consistently shown that pesticide exposure can impact bee behavior, with cascading effects on foraging performance, reproductive success, and pollination services. However, these studies typically assess only one chemical, neglecting the complexity of real‐world exposure to multiple agrochemicals and other stressors. In the summer of 2020, we collected wild‐foraging workers of the common eastern bumblebee, Bombus impatiens, from five squash (Cucurbita) agricultural sites (organic and conventional farms), selected to represent a range of agrochemical, including neonicotinoid insecticide, use. For each bee, we measured two behaviors relevant to foraging success and previously shown to be impacted by pesticide exposure: sucrose responsiveness and locomotor activity. Following behavioral testing, we used liquid chromatography–tandem mass spectrometry (LC–MS/MS) chemical analysis to detect and quantify the presence of 92 agrochemicals in each bumblebee. Bees collected from our sites did not vary in pesticide exposure as expected. While we found a limited occurrence of neonicotinoids, two fungicides (azoxystrobin and difenoconazole) were detected at all sites, and the pesticide synergist piperonyl butoxide (PBO) was present in all 123 bees. We found that bumblebees that contained higher levels of PBO were less active, and this effect was stronger for larger bumblebee workers. While PBO is unlikely to be the direct cause of the reduction in bee activity, it could be an indicator of exposure to pyrethroids and/or other insecticides that we were unable to directly quantify, but which PBO is frequently tank‐mixed with during pesticide applications on crops. We did not find a relationship between agrochemical exposure and bumblebee sucrose responsiveness. To our knowledge, this is the first evidence of a sublethal behavioral impact of agrochemical exposure on wild‐foraging bees. [ABSTRACT FROM AUTHOR]

Simple Summary: This study investigated the sublethal effects of three insecticides (spirotetramat, cyantraniliprole, and pymetrozine) on Aphis gossypii. The effects of sublethal concentrations (LC10, LC30, LC50, and LC70) of the insecticides on the developmental period, survival rate, adult longevity, fecundity, and deformity rate were compared with those of the control. Spirotetramat and cyantraniliprole caused malformation in the F1 but not the F2 generation of A. gossypii. The net reproductive rate (R0) decreased significantly compared to that of the control (43.8) for all insecticides except cyantraniliprole at the LC10 (37.5). Therefore, sublethal concentrations (over the LC30) of the three insecticides could aid in the management of A. gossypii by affecting its population density. The toxicity and sublethal effects of three insecticides (spirotetramat, cyantraniliprole, and pymetrozine) on Aphis gossypii, a major agricultural pest, were investigated. The nymphal stage showed greater susceptibility than the adult stage to all the insecticides, with a difference of up to 8.9 times at the LC50 of spirotetramat. The effects of sublethal concentrations (LC10, LC30, LC50, and LC70) of the insecticides on the on the developmental period, survival rate, adult longevity, fecundity, and deformity rate were compared with those of the control. Compared with the control, cyantraniliprole and pymetrozine did not significantly affect the developmental period in the parental or F1 generation when applied at the nymphal stage at any concentration. Nonviable nymphs occurred in the F1 generation when both nymphs and adults were treated with spirotetramat and cyantraniliprole but not in the F2 generation. The age-specific maternity (lxmx) of A. gossypii treated with sublethal concentrations (LC10, LC30) decreased with increasing concentration. Spirotetramat at the LC30 resulted in significant differences in all life table parameters (R0, rm, λ, T, DT) compared with those of the control. Similarly, compared with that of the control (43.8), the net reproductive rate (R0) significantly decreased for all the insecticides except cyantraniliprole at the LC10 (37.5). Therefore, this study indicated that sublethal concentrations (over the LC30) of spirotetramat, cyantraniliprole, or pymetrozine might be useful for the density management of A. gossypii. [ABSTRACT FROM AUTHOR]

Allium mongolicum Regel leaf beetle, Galeruca daurica (Coleoptera: Chrysomelidae) is rampantly harmful in Inner Mongolia grassland. However, the current management strategies for this pest still heavily rely on chemical control using traditional insecticides or those with novel action. In the study, we conducted an indoor bioassay to evaluate the sublethal effects of chlorantraniliprole on the biological characteristics. Additionally, we assessed the activity of detoxification enzymes, specifically the primary enzymes carboxylesterase (CarE) and cytochrome P450, and insect's secondary metabolic enzymes, namely glutathione S‐transferase (GST) and uridine diphosphate glycosyltransferase (UGT), as well as its gene expression profile. The developmental period of the 3rd instar larvae of G. daurica was significantly prolonged after treatment with chlorantraniliprole, which negatively affected the hatching, pupation and diapause rates as well as their body weight. The larvae showed different dynamics of the enzyme activities within 24 h of chlorantraniliprole treatment. Different sublethal concentrations of chlorantraniliprole showed an inducing effect on the activities, while no significant difference in activity was observed for P450. Expression profiling of detoxifying enzyme genes screened by transcriptome data has revealed that 6 CarE, 2 GST, 7 UGT and 31 P450 genes were up‐regulated. In conclusion, chlorantraniliprole's sublethal effect on 3rd instar G. daurica larvae resulted in a deceleration of their growth and developmental processes and significantly increased the activity levels of CarE, GST and UGT. The detoxifying proteins encoded by up‐regulation genes may involve in the detoxification metabolism of chlorantraniliprole. Our results provide a basis for understanding the molecular mechanisms of chlorantraniliprole action and detoxification in this key grassland insect pest. [ABSTRACT FROM AUTHOR]

Background: Indoor residual spraying (IRS) capitalizes on the natural behavior of mosquitoes because Aedes aegypti commonly seeks indoor resting sites after a blood meal. This behavior allows mosquitoes to be exposed to insecticide-treated surfaces and subsequently killed. Combinations of deltamethrin and clothianidin with different modes of action have shown promise in IRS, effectively targeting both susceptible and pyrethroid-resistant malaria vectors. However, the effects of this approach on Aedes mosquitoes remain unclear. The present study tested the effects of deltamethrin–clothianidin mixture treatment on behavioral responses and life history traits of Taiwanese and Indonesian populations of Ae. aegypti. Methods: We adopted an excito-repellent approach to explore the behavioral responses of pyrethroid-resistant Ae. aegypti populations from Indonesia and Taiwan to a deltamethrin–clothianidin mixture used in contact irritancy and non-contact repellency treatments. We further evaluated the life history traits of surviving mosquitoes (i.e., delayed mortality after 7-day post-treatment, longevity, fecundity, and egg hatching) and investigated the potential transgenerational hormetic effects of insecticide exposure (i.e., development rate and survival of immatures and adult mosquitos). Results: All tested field populations of Ae. aegypti displayed strong contact irritancy responses; the percentage of escape upon insecticide exposure ranged from 38.8% to 84.7%. However, repellent effects were limited, with the escape percentage ranging from 4.3% to 48.9%. We did not observe immediate knockdown or mortality after 24 h, and less than 15% of the mosquitoes exhibited delayed mortality after a 7-day exposure period. However, the carryover effects of insecticide exposure on the survival of immature mosquitoes resulted in approximately 25% higher immature mortality than that in the control. By contrast, we further documented stimulated survivor reproduction and accelerated transgenerational immature development resulting from the sublethal effects of the insecticide mixture. In particular, the number of eggs laid by treated (both treatments) female mosquitoes increased by at least 60% compared with that of eggs laid by control female mosquitoes. Conclusions: IRS with deltamethrin–clothianidin effectively deters Aedes mosquitoes from entering residential areas and thereby reduces mosquito bites. However, the application rate (deltamethrin: 25 mg/m2; clothianidin: 200 mg/m2) may be insufficient to effectively kill Aedes mosquitoes. Insecticide response appears to vary across mosquito species; their behavioral and physiological responses to sublethal doses have crucial implications for mosquito control programs. [ABSTRACT FROM AUTHOR]

Considering the influence of sublethal concentration of pesticides on pests and natural enemies, we propose a pest-management model with impulsive effect on chemical control and biological control strategies–periodic spraying pesticide and releasing predatory natural enemies. By using the Floquet theory and the comparison theorem of impulsive differential equations, a sufficient condition for the global asymptotic stability of the pest-eradication periodic solution is obtained. The persistence of the system is further studied, and a sufficient condition for the persistence of the system is obtained. Finally, some numerical simulations are shown to verify our theoretical works. Our works indicate that the sublethal effects of insecticides and the release of predatory natural enemies play significant roles in pest control in agricultural production. [ABSTRACT FROM AUTHOR]

Increasing awareness of cadmium (Cd) pollution in agroecosystems has highlighted the need for a better understanding of the cascading effects heavy metals on the fitness of herbivores and their natural enemies, as well as the potential impact on the efficacy of integrated pest management (IPM). In this study, we assessed the bottom-up effects mediated by Cd on two important egg parasitoids, Trichogramma japonicum and T. dendrolimi via their factitious host, the rice moth Corcyra cephalonica. Results showed that the bottom-up effects mediated by Cd are complex. Cd exposure at 20 mg/kg in artificial diets of rice moth larvae enhanced the weight of eggs laid once they have reached adulthood, increased the proportion of females produced, and stimulated reproduction, thus suggesting a hormesis response. A stimulation effect on T. dendrolimi fitness was also found (when developing from contaminated rice moth eggs), but T. japonicum instead had a reduced fitness. In addition, unexposed adult parasitoids (reared from uncontaminated hosts) were not able to discriminate between uncontaminated or contaminated eggs (produced by rice moths reared on Cd-diet). Our results show that Cd contamination should not interfere with the effectiveness of inundative releases of T. japonicum, but the capacity of the subsequent F1 generation of parasitoids in controlling pest populations could be affected by Cd contamination. This suggests that inundative releases should be favored over inoculative releases in Cd-contaminated sites, and mixed-species releases of Trichogramma could increase the cost effectiveness of pest biological control. [ABSTRACT FROM AUTHOR]

The fall armyworm (FAW), Spodoptera frugiperda (J. E. Smith) is a highly destructive pest of many crops. Emamectin benzoate (EMB) is a major insecticide for the management of FAW, however potential sublethal effects and regulating mechanisms on the development of FAW remain unknown. In this context, we exposed FAW to two EMB concentrations (LC10 or LC30) and then assess sublethal effect(s) on FAW development and reproduction, as well as evaluated potential regulating mechanisms. We showed that EMB prolonged the larval development time, pupal duration time and adult longevity, and increased pupal weight and fecundity/female, while lowered pupation rate (compared to control group). EMB also impaired FAW larvae molting and reduced levels of ecdysteroids in third-instar larvae and 1st-day pupae. Two new ecdysteroid biosynthesis genes, Neverland (SfNvd) and Shroud (SfSro) were identified from FAW. The spatial and temporal expression patterns and the changes in mRNA levels under EMB exposure of SfNvd and SfSro, along with five Holloween genes, were monitored. Six genes, including SfCYP306A1, SfCYP302A1, SfCYP307A1, SfSro, SfCYP314A1, and SfCYP315A1 were significantly induced, and SfNvd were decreased after exposure to LC10 or LC30 of EMB at specific developmental stages, while SfCYP307A1 was increased by LC10 in pupa and decreased by LC10 and LC30 of EMB in adults. These results suggest that EMB inhibits ecdysteroid biosynthesis by regulating ecdysteroid biosynthetic enzyme genes, thus resulting in ecdysis failure and disruption of larval development. [ABSTRACT FROM AUTHOR]

The cotton bollworm, Helicoverpa armigera, stands as a major agricultural pest, displaying resistance to a diverse range of insecticides. Diflubenzuron, a member of the benzoylurea class of insecticides, serve by suppressing the synthesis of chitin in insects. This disruption hampers their typical metamorphic processes like molting and pupation, ultimately culminating in death. In this study, the toxicity of diflubenzuron against H. armigera was investigated. The results showed that the LC50 of diflubenzuron on 3rd instar bollworm was 109 mg/kg after 7-day exposure. Most importantly, diflubenzuron treatment led to a change in the chitin synthesis pathway, accompanied by a significant surge in chitinase (HaChi) expression. The feasibility of combining with RNA interference (RNAi) technology to control cotton bollworm was further explored. We demonstrated that three chitin synthesis pathway genes Chitin synthase 1 (HaCHS1), chitin synthase 2 (HaCHS2) and HaChi were significantly inhibited following exposure to dsRNAs, leading to the death of cotton bollworm. Among these, the dsHaCHi treatment group manifested the most significant effect. Subsequent combined treatment of 3rd instar larvae with dsHaChi and diflubenzuron reduced survival rates of cotton bollworm by 24% and 15.33%, respectively. Simultaneously, there were recognized effects on larval weight, pupal weight, and pupation rate to varying degrees. This study underscores the potential of combining RNAi technology with conventional chemical pesticides, this combination can improve pest control efficiency, and offers a novel strategy to compensate for the low RNAi efficiency in lepidopteran insects, consequently reducing the dependency on chemical pesticides. [ABSTRACT FROM AUTHOR]

As one of the most important invasive and destructive pests in the world, the fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae) reduces crop yield and causes economic loss. It is critical to find an appropriate controlling approach. This study aimed to determine the insecticidal activities of botanical insecticides (30% tea saponin, 0.6% matrine and a mixture thereof) on fall armyworm larvae, as well as the effects of sublethal concentrations of an optimal ratio of the mixture, on the survival rate, developmental duration, pupation rate, emergence rate, and body weight of fall armyworm. In addition, we evaluated the control effect of the insecticides (30% tea saponin, 0.6% matrine, optimal ratio of mixture along with 0.3% azadirachtin and 36% chlorfenapyr) and toxicity to natural enemies in field conditions. The results showed that all botanical insecticides and mixtures were toxic, and the insecticidal bioactivity of 10:1 volume ratio mixture was the highest at 96 hours, with a median lethal concentration (LC50) of 56.561 mg/mL. Meanwhile, the sublethal concentration of a 10:1 volume ratio of the mixture significantly affected the survival rate, prolonged developmental duration and reduced emergence rates and pupal weights, but it did not affect the pupation rates of fall armyworm. Furthermore, it has harmless or slightly harmful effects on natural enemies. Our study provides a novel environmentally friendly and natural enemy-friendly approach to controlling fall armyworms. [ABSTRACT FROM AUTHOR]

Eretmocerus hayati is an effective biocontrol agent against whitefly Bemisia tabaci. Thiamethoxam, abamectin, and sulfoxaflor are the commonly used insecticides for whitefly control. We explored the sublethal and transgenerational effects of these insecticides on E. hayati in laboratory by exposing the parental pupae to the maximum field-recommended concentration of each insecticide. The adult longevity and host control efficiency of F0 generation treated with insecticides decreased significantly compared with control. Demographic characteristics, parasitism and host-feeding rate of E. hayati F1 progeny was analyzed using the age-stage, two-sex life table, and the CONSUME-MSChart computer program. The results indicated that most life traits of E. hayati F1 generation, including the development duration of immature, longevity of female adults, oviposition days and fecundity were negatively affected by thiamethoxam. However, except for the prolonged development duration of pupae, no significant negative effect on other demographic parameters or population parameters of E. hayati F1 generation were observed in both abamectin and sulfoxaflor groups. The net host-feeding rate and whitefly-killing rate (parasitism + host-feeding) of E. hayati F1 females were adversely affected by thiamethoxam but not affected by abamectin and sulfoxaflor. Thiamethoxam had the most severe sublethal and transgenerational effects on E. hayati of the three insecticides tested. However, abamectin was more compatible with release of E. hayati, especially when applied during the E. hayati pupal stage. These findings provide insights into comprehensively understanding of the effects of insecticides used in whitefly control as well as the integrate management of B. tabaci. [ABSTRACT FROM AUTHOR]

The insecticide industry has developed more bee-safe active ingredients such as flupyradifurone. However, recent research provides evidence of the negative effects of this and its possible influence on the deterioration of the health of pollinators. During the experiment, mixed-age worker bees of A. mellifera were exposed to a single, sublethal oral dose of flupyradifurone (645 ng/bee) and were assessed only for the first day after exposure to 0.5, 1, 3, 6, and 24 hours. Using reverse transcriptase polymerase chain reaction (RT-qPCR), the alteration in gene expression caused by exposure to this insecticide was quantified. A total of five genes were quantified: three primary antioxidant genes (Catalase (CAT), Superoxide dismutase (SOD1) and Thioredoxin dismutase (Trxr1), one detoxification gene (Cytochrome P450 9Q3 (CYP9Q3)) and one gene with neuronal activity (Acetylcholinesterase, AChE1). The endogenous ribosomal protein S18 (RPS18) gene allowed the estimation of relative gene expression as the response to insecticide exposure. The AChE1 gene was overexpressed up to six hours after exposure; the remaining CYP9Q3, CAT, SOD1, and Trxr1 genes presented a similar behavior. At a sublethal dose and at short time intervals, flupyradifurone causes alteration in the relative expression of five genes in individual honeybees after oral exposure, which could cause a long-term adverse effect on hive health. [ABSTRACT FROM AUTHOR]

Brevipalpus yothersi is an important pest to citrus crop due to its ability to transmit the virus that causes citrus leprosis. The exposure of target and non-target organisms to different pesticides is a reality in field conditions. For successful management, it is essential to determine the effects of citrus commonly used pesticides on leprosis mites to determine how pesticides can interfere with the leprosis mite population. Therefore, this study aimed to evaluate the impact of insecticides, alone or associated with spirodiclofen, on B. yothersi life history traits and demographic parameters under laboratory and greenhouse conditions. Results suggest that cypermethrin and imidacloprid, both alone and in a mixture with spirodiclofen, phosmet in a mix with spirodiclofen and spirodiclofen alone did not interfere significantly in the fecundity and fertility of B. yothersi in laboratory conditions. In the same condition, only phosmet at 15.6, 125.0, and 250.0 mg.L-1 reduced the fecundity of the mites. Brevipalpus yothersi population varied with the insecticide and mixture type in the greenhouse condition. Most insecticides and acaricide, alone or in a mixture, decreased pre-adult development, whereas female adult longevity was similar to control. Spirodiclofen combined with phosmet and imidacloprid decreased female adult longevity. Only spirodiclofen in a mixture with cypermethrin and phosmet alone did not interfere significantly with the intrinsic rate of population increase. The other insecticides and mixtures reduced that parameter. The mean time of one mite generation was decreased when the mites were exposed to all insecticides and acaricide combinations, spirodiclofen and phosmet alone. Therefore, cypermethrin, phosmet, imidacloprid, and spirodiclofen, alone or in a mixture, negatively impacted the development time and demographic parameters of B. yothersi. [ABSTRACT FROM AUTHOR]

Simple Summary: The citrus fruit borer has become one of the main pests in citrus orchards in Brazil, possibly due to biological imbalances caused by multiple insecticide applications. This pest is managed with insecticides, but studies indicate a potential use of Trichogramma atopovirilia to control its eggs. In this way, we evaluated the selectivity of new products that could eventually be used in the Brazilian citrus orchards on T. atopovirilia. Among the products tested, spinetoram was considered harmful. Cyantraniliprole, cyantraniliprole + abamectin, abamectin, sulfoxaflor, and the entomopathogenic fungi Cordyceps fumosorosea were considered selective and non-persistent to the parasitoid. In Brazil, the citrus fruit borer, Gymnandrosoma aurantianum Lima, 1927, is a serious pest in orange orchards, causing an annual loss of 80 million US dollars, and is managed with multiple insecticide applications, often 56 in a single season. On the other hand, the parasitoid wasp Trichogramma atopovirilia Oatman & Platner, 1983 has the potential for controlling G. aurantianum by attacking its eggs. Considering the intensive insecticide applications in citrus orchards in Brazil to control the large complex of pests, especially Diaphorina citri Kuwayama, 1908, evaluation of the harmful effects of insecticides on T. atopovirilia is important to maximize efficiency in managing G. aurantianum. Here, we tested the effects of new products used in citrus orchards (cyantraniliprole, cyantraniliprole + abamectin, abamectin, sulfoxaflor, spinetoram, flupyradifure, and Cordyceps fumosorosea (Wize) Kepler, B. Shrestha & Spatafora) on adults and pupae of T. atopovirilia. Of the insecticides tested, spinetoram caused the highest impacts on T. atopovirilia parasitism, longevity, emergence, and mortality. The other products caused more sublethal than lethal effects and were classified as 1 and/or 2 in the IOBC/WPRS classification. Abamectin, cyantraniliprole, cyantraniliprole + abamectin, and the entomopathogenic fungus C. fumosorosea were classified as short-lived. Except for spinetoram, these products were classified as selective. In this study, spinetoram was considered harmful to T. atopovirilia and, therefore, should be managed carefully in IPM programs combining this parasitoid. In order to safely use this insecticide, one should respect the interval of release of the parasitoid, which is 21 days after its spraying. The novel products tested, cyantraniliprole, cyantraniliprole + abamectin, abamectin, sulfoxaflor, and the entomopathogenic fungi C. fumosorosea were selective and non-persistent to T. atopovirilia. These products are possible replacements for non-selective insecticides to achieve higher control from both chemical and biological tools. [ABSTRACT FROM AUTHOR]

Thrips hawaiiensis (Morgan) (Thysanoptera: Thripidae) is a sap-sucking pest that seriously damages several crops and reduces their economic value. Exposure to low concentrations of insecticides may have a sublethal effect on surviving insects. In order to provide a reference for the rational application of emamectin benzoate, its sublethal effects on the development and reproduction of T. hawaiiensis were evaluated. Pupal development time was significantly shorter in T. hawaiiensis treated with sublethal concentrations of emamectin benzoate (LC10 and LC20) than in control. Female adult longevity and female total longevity were significantly longer following LC20 treatment than in the control and LC10 treatment groups. Nevertheless, male adult longevity and male total longevity were significantly shorter in the LC10 treatment group than in the control and LC20 treatment groups. The sublethal concentration of emamectin benzoate (LC20) significantly shortened the preadult stages and the mean generation. Meanwhile, it significantly increased the finite rate of increase, intrinsic rate of increase, and net reproductive rate. The fecundity was significantly higher after LC20 treatment than after LC10 and control treatments. Compared with the control group, the LC10 and LC20 groups of T. hawaiiensis adults showed a significantly higher expression of the vitellogenin (Vg) and vitellogenin receptor (VgR) genes, which played a key role in increasing their fecundity. These findings suggest that short-term exposure to sublethal concentrations of emamectin benzoate may lead to a resurgence and secondary outbreak of T. hawaiiensis infestation. The results have practical applications for the management of this important and noxious pest. [ABSTRACT FROM AUTHOR]

Tetranychus urticae Koch. (Acari: Tetranychidae) is one of the most important major pests that damage both agricultural production areas and many other commercially grown plants across the world. Agricultural producers generally prefer pesticides to control pests. However, the pesticides are sometimes used without consideration for their effects on non-target organisms. In addition, in some cases, the dose adjustment for the pesticides prior to application is incorrectly applied. In this case, the associated overdose or low dose may lead to changes in the biological parameters of the target and the non-target organisms. In this study, we investigated the effect of imidacloprid, thiacloprid, deltamethrin and cypermethrin on reproduction parameters and lifespan of T. urticae using their field recommended dose (FRD) and half of the field recommended dose (FRD/2). Insecticides and pure water (control) were applied to the larvae of the T. urticae found on the leaves on the wet cotton of the Petri dish by spray towers. Compared to the control, the developmental times for the larvae on test unit treated with deltamethrin and cypermethrin at FRD and FRD/2 were considerably longer. The developmental period of larvae treated with thiacloprid at the FRD, however, was significantly shorter than the control (P < 0.05). The duration of adults preoviposition from thiacloprid administered at the FRD/2 was significantly increased compared to the control (P < 0.05). The lifespan (4.89 days) and the duration of oviposition period (5.05 days) of adults obtained from larvae treated with imidacloprid at FRD was significantly shorter compared to the control (P < 0.05). Thus, thiacloprid at the FRD/2 significantly increased the preoviposition time (1.10 days) compared to the control (0.50 days) (P < 0.05). Deltamethrin at the FRD and FRD/2 significantly increased the preoviposition duration compared to control (P < 0.05). [ABSTRACT FROM AUTHOR]

Brevicoryne brassicae L., better known as the cabbage aphid, is a significant pest of the Brassicaceae family. This study aimed to investigate the compatibility of entomopathogenic fungi (EPF), namely Acremonium sclerotigenum FCCUU490 and Lecaniciliium muscarium FCCUU420, with imidacloprid (Confidor®), on the biological characteristics and life table of Diaeretiella rapae (Hymenoptera: Braconidae), a parasitoid of Brevicoryne brassicae (Hemiptera: Aphididae). Results showed that the percentage germination of conidia in A. sclerotigenum and L. muscarium did not differ significantly between combination treatments and the control, which indicates imidacloprid did not affect fungi germination. The oviposition period of D. rapae exposed to imidacloprid (LC25 = 9.2 ppm) was 2.73 d, the lowest one among treatments, and the best one was for L. muscarium (LC12.5 = 1.4 × 101 conidia ml−1) plus imidacloprid (LC12.5 = 5.5 ppm). Imidacloprid had the most negative effects on all the tested parameters. A. sclerotigenum and L. muscarium had the least negative effect on D. rapae. Female adults had 3.6 d long life in mixed (L. m. and Imid) treatment in comparison to imidacloprid with 2.8 d. The life expediency (exj) of imidacloprid was the lowest for females among the treatments. Considering the significance of sublethal effects of EPF and imidacloprid on D. rapae, the use of these two EPF alone or in combination with sublethal concentrations of imidacloprid in integrated management of cabbage aphids is recommended. According to the parameters of the life table of these two EPF alone or in combination with sublethal concentrations of imidacloprid that had the lowest side effect on D. rapae, the use of these treatments in integrated management of cabbage aphids is recommended. [ABSTRACT FROM AUTHOR]

Rice (Oryza sativa) is the most important food crop all over the world, while white-backed planthopper (WBPH), Sogatella furcifera (Horváth) (Hemiptera: Delphacidae) is an important pest causing rice yield reduction. The purpose of this study is to evaluate the sublethal effects of strain BEdy1 Beauveria bassiana (Bals.-Criv.) Vuill. (Hypocreales: Cordycipitaceae) on S. furcifera using the two-sex life table analytical method, compare the life tables of the F0 and F1 generations of WBPHs which were treated with sublethal concentrations (LC10, LC25) of B. bassiana BEdy1 with a control group. The results showed that the duration of the egg, 4th-instar and 5th-instar nymph, pre-adult, total pre-oviposition (TPOP) and mean generation time (T) for the LC25 treatment were significantly longer than those of the control and LC10 treatment. However, the duration of the adult, the longevity of male and female adults and the oviposition days of female adults for the LC25 treatment were significantly shortened. The fecundity of female adults, intrinsic rate of increase (r), net reproductive rate (R0) and finite rate of increase (λ) for the LC25 treatment were significantly decreased compared with those of other treatments. The duration of the egg and pre-adult stage for the LC10 treatment were longer than those of the control group, but the population parameters showed no significant difference. Therefore, the LC25 of B. bassiana BEdy1 can inhibit the population growth of S. furcifera. [ABSTRACT FROM AUTHOR]

Brown planthopper (Nilaparvata lugens) (BPH) is a devastating migratory rice pest in tropical, subtropical, and temperate regions. Insecticide-induced population resurgence is a concern for BPH control. Exposure to low/sublethal concentrations of insecticides has resulted in increased reproduction and fitness as well as insecticide tolerance in many insects. Nitenpyram, a neonicotinoid insecticide, has been frequently used in BPH control. In the present study, the transgenerational hormesis effects in terms of fitness-related traits and insecticide tolerance induced by low concentrations of nitenpyram were reported in both susceptible (S) and field-collected strains (F) of BPH, after exposure to their respective LC20 nitenpyram concentrations for six generations. Our findings stressed that chronic, multigenerational preconditioning of BPHs to LC20 nitenpyram not only increased the biological fitness (in terms of life table parameters and estimated population size), but also primed BPHs to be more tolerate/resistant to insecticides nitenpyram, imidacloprid and cycloxaprid. The upregulation of detoxification (CYP6ER1) and fecundity-related (vitellogenin) genes in both the LC20-preconditioned S and F strains (S-Sub6 and F-Sub6) might contribute to the increased insecticide tolerance and reproduction hormesis. These results support the hypothesis that BPH population outbreaks following multigenerational exposure to low concentrations of nitenpyram in field crops occur through increased reproduction and resistance development. Moreover, based on our results, sulfoxaflor and triflumezopyrim are proposed to be used in rotation with nitenpyram, imidacloprid or cycloxaprid to delay the development of tolerance/resistance in BPHs in paddy fields. [ABSTRACT FROM AUTHOR]

Simple Summary: Insecticides are considered to be one of the major factors of bee decline. In this study, the potential sublethal effects of selected neonicotinoids on honey bee larvae were investigated by protein expression profiling for the first time. The total larval protein expression was investigated by 2D gel electrophoresis after exposure to the insecticides dimethoate, fenoxycarb and flupyradifurone. Protein spots whose concentrations differed significantly from the controls were sequenced and identified against known insect proteins. Although the treated larvae did not show increased mortality or an aberrant development, the proteome comparisons showed differences in the metabolism, immune response and energy supply of the bee larvae. The strongest influence was found for flupyradifurone, which activates various detoxification pathways, the immune response or tissue regeneration. Our results suggest that there may be a delayed larval development or possibly a reduced honey bee brood vitality at sublethal concentrations. The western honey bee Apis mellifera is globally distributed due to its beekeeping advantages and plays an important role in the global ecology and economy. In recent decades, several studies have raised concerns about bee decline. Discussed are multiple reasons such as increased pathogen pressure, malnutrition or pesticide use. Insecticides are considered to be one of the major factors. In 2013, the use of three neonicotinoids in the field was prohibited in the EU. Flupyradifurone was introduced as a potential successor; it has a comparable mode of action as the banned neonicotinoids. However, there is a limited number of studies on the effects of sublethal concentrations of flupyradifurone on honey bees. Particularly, the larval physiological response by means of protein expression has not yet been studied. Hence, the larval protein expression was investigated via 2D gel electrophoresis after following a standardised protocol to apply sublethal concentrations of the active substance (flupyradifurone 10 mg/kg diet) to larval food. The treated larvae did not show increased mortality or an aberrant development. Proteome comparisons showed clear differences concerning the larval metabolism, immune response and energy supply. Further field studies are needed to validate the in vitro results at a colony level. [ABSTRACT FROM AUTHOR]

The side effects of insecticides on non‐target species are important to secure the intended effectiveness of pest management programmes. The cotton aphid Aphis gossypii is a frequent problem in industrial greenhouse cultivation, and insecticide and parasitoids are often used for crop protection. Among insecticides, mixtures are playing increasing roles in pest management in the greenhouse production system, as well as parasitoid use. The insecticide mixture thiacloprid + deltamethrin and the parasitoid wasp Aphidius colemani are the main agents used against the cotton aphid and are the focus of this study. Here, we report the effects of the thiacloprid + deltamethrin on A. gossypii and Ap. colemani. The low concentrations 2.79 g a.i/L (LC10) and 7.28 g a.i/L (LC30) compromised the life parameters of the aphid progeny and increased the development time at all juvenile stages. In addition, fecundity, longevity and other parameters (r, R0 and T) were significantly impaired by thiacloprid + deltamethrin at both concentrations. The median lethal time estimate (LT50) for Ap. colemani was 18.73 h; the parasitoid mortality was significant up to 24 h after application but decreased afterward. Regardless, the parasitoid life table parameters were also compromised by insecticide exposure, similarly to the parasitoid population growth and parasitism efficacy. These results demonstrate the effect of the insecticide mixture against A. gossypii, and the increased risk of its adverse impacts on the parasitoid Ap. colemani, which signals against their simultaneous application to control this pest species. [ABSTRACT FROM AUTHOR]

(1) Background: Fluxametamide is a novel isoxazoline insecticide. Rice stem borer Chilo suppressalis (Walker) is a destructive Lepidoptera pest of rice in China, and novel effective insecticides are required to be developed for controlling it due to its increasing resistance levels. (2) Results: In the lethal assay, the insecticidal activity of fluxametamide with median lethal dose (LD50) value of 1.308 mg/kg to the fourth-instar larvae of C. suppressalis was higher than that of chlorantraniliprole (LD50, 3.112 mg/kg) and lower than that of emamectin benzoate (LD50, 0.006 mg/kg). In the sublethal (LD10 and LD30) assay, the duration of third to sixth-instar larvae, the pupal duration, pupation rate, and life cycle rate were significantly increased in F0 generation. Both the length and weight of the ovarian tube were decreased with the dose increase of fluxametamide, and were significantly smaller in the LD30 treatment than those of the control group. In F1 generation, only the duration of eggs was significantly increased with LD30 treatment of fluxametamide, whereas other developmental parameters had no significant change. (3) Conclusion: Fluxametamide had relatively strong lethal and sublethal effects on C. suppressalis and probably was able to affect the population growth and progeny of C. suppressalis. [ABSTRACT FROM AUTHOR]

The fall armyworm (FAW), Spodoptera frugiperda, causes substantial annual agricultural production losses worldwide due to its resistance to many insecticides. Therefore, new insecticides are urgently needed to more effectively control FAW. Cyclosporin A (CsA) is a secondary metabolite of fungi; little is known about its insecticidal activity, especially for the control of FAW. In this study, we demonstrate that CsA shows excellent insecticidal activity (LC50 = 9.69 μg/g) against FAW through significant suppression of calcineurin (CaN) activity, which is a new target for pest control. Combinations of CsA and indoxacarb, emamectin benzoate, or Vip3Aa showed independent or synergistic toxicity against FAW; however, the combination of CsA and chlorantraniliprole showed no toxicity. Sublethal doses of CsA led to decreases in FAW larval and pupal weight, pupation, emergence, mating rates, adult longevity, extended development of FAW larvae and pupae and the pre-oviposition period of adults, and increases in the proportion of pupal malformation. Importantly, CsA treatment reduced FAW ovarian size and female fecundity, which suggests that it has great potential to suppress FAW colony formation. Taken together, these results indicate that CsA has high potential as an insecticide for controlling FAW. [ABSTRACT FROM AUTHOR]

Broflanilide, a novel meta-diamide insecticide, has been registered worldwide to control agricultural pests, and cause negative influence to insects under not only lethal but also sublethal levels in the field. Fall armyworm (FAW), Spodoptera frugiperda, is a worldwide distributed insect frequently controlled by using insecticides. The molecular mechanisms by which broflanilide acts have yet to be fully characterized. In the present study, we exposed FAW larvae to sublethal dose (LD5), low lethal doses (LD10 and LD30) and median lethal dose (LD50) of broflanilide and measured various subsequent physiological sublethal effects. FAW larvae body length became shorter (LD5-LD50), the larvae and pupae duration were increased by 0.96-4.63 days (LD5-LD50), and the juvenile hormone (JH) titer significantly increased up to 134.46% (LD10-LD30). Meanwhile, the JH acid methyltransferase (JHAMT) and farnesyl diphosphate synthase 1 (FPPS1), which are critical enzymes of JH biosynthesis, respectively increased by 2.07- and 2.18- fold in the LD10 broflanilide-treated group, and by 2.22- and 1.78- fold in LD30 broflanilide-treated group in 3rd day larvae of FAW. In the 12-hour-old adults, SfrFPPS1 increased to 1.92-fold in the LD30 broflanilide-treated group. Broflanilide induced multiple physiological sublethal effects on the biosynthesis of JH by regulating the expression of SfrFPPS and SfrJHAMT genes in FAW and likely in other insects (both pests and non-target organisms). Therefore, its potential for Integrated Pest Management should be further assessed. [ABSTRACT FROM AUTHOR]

Simple Summary: The oriental fruit fly, Bactrocera dorsalis, is a pest that causes huge economic losses in the fruit and vegetable industry. β-cypermethrin has been widely used in the orchard to control this major pest. According to a previous study, the oriental fruit fly developed significant resistance against β-cypermethrin in fields, which indicated that the oriental fruit fly has been exposed to sublethal concentrations of β-cypermethrin in the field for a long time. However, the sublethal effect and its mechanism are still unclear. In our present study, after treatment with sublethal concentrations of β-cypermethrin, the olfaction was disrupted significantly and the chemosensory genes were suppressed obviously. Our data demonstrated that the sublethal dose of β-cypermethrin impairs the olfaction of the pest insects by suppressing the expression of chemosensory genes, which provided theoretical guidance for the rational use of pesticides in fields. The oriental fruit fly, Bactrocera dorsalis, is one of the most destructive fruit insect pests. β-cypermethrin has been widely used in the orchard to control this major insect. Based on the resistance monitoring in 2011, B. dorsalis developed significant resistance against β-cypermethrin in fields. This indicated that the B. dorsalis has been exposed to sublethal concentrations of β-cypermethrin in the field for a long time. Thus, it is urgent to understand the sublethal effects of β-cypermethrin on this fly to guide the rational use of an insecticide. According to the olfactory preference assays and electroantennogram (EAG) recording, the B. dorsalis after β-cypermethrin exposure (LD30 = 10 ng/fly) severely decreased the ability to perceive the tested odorants. Moreover, we then performed quantitative real-time PCR and found the chemosensory genes including odorant receptor co-receptor (BdorORco) and ionotropic receptor co-receptors (BdorIRcos) were obviously suppressed. Our results demonstrated that the sublethal dose of β-cypermethrin impairs the olfaction of the pest insects by suppressing the expression of chemosensory genes (BdorORco and BdorIRcos), which expanded our knowledge of the sublethal effects of the pesticide on insects. [ABSTRACT FROM AUTHOR]

Many essential oils have excellent insecticidal activity and have the potential to be developed as alternatives to chemical insecticides for pest control. Previously, we showed that β‐asarone, a major constituent of the essential oil derived from Acorus calamus L. (Acoraceae), has strong pesticidal activity against brown planthopper, Nilaparvata lugens (Stål) (Hemiptera: Delphacidae), the most notorious rice pest in Asia. Here, we report the first evaluation of the sublethal and transgenerational effects of β‐asarone on N. lugens. β‐Asarone significantly decreased female longevity, male longevity, fecundity, and hatchability of F0 generation individuals exposed to the LD30 and LD45 of β‐asarone relative to the acetone control. Moreover, compared with acetone, exposure to LD30 and LD45 of β‐asarone significantly shortened the duration of the egg stage, developmental duration of first instars, and female longevity of F1 generation individuals. Furthermore, the intrinsic rate of increase (r), finite rate of increase (λ), and net reproductive rates (R0) of insects treated with LD30 and LD45 of β‐asarone were significantly lower than those of insects treated with acetone. Compared with acetone, the fecundity and hatchability of F1 generation individuals were significantly decreased after exposure to β‐asarone at LD30 and LD45. These findings indicate the negative effects of sublethal doses of β‐asarone on N. lugens and provide novel information on the potential use of β‐asarone as a substitute chemical pesticide. [ABSTRACT FROM AUTHOR]

This is the first field study in which we have tested the efficacy of four different entomopathogenic fungal (EPF) formulations together in single study—i.e., Green Muscle, Green Guard, Metarhizium anisopliae, and an isolate of Beauveria bassiana (isolate WG-11)—against nymphs and adults of the desert locust, Schistocerca gregaria Forskål (Orthoptera: Acrididae). We conducted several different studies: (a) lethal bioassay against the 3rd, 5th, and adult stages under laboratory conditions; (b) sublethal effects on the reproduction, diet consumption, fecal production, and weight gain; (c) a greenhouse trial; and (d) a field cage trial. Under laboratory conditions, all EPF formulations caused significant mortality, and the highest efficacy was observed with Green Muscle, followed by Green Guard, B. bassiana, and M. anisopliae. Susceptibility was found to be greatest in 3rd-instar nymphs, followed by 5th instars, and then adults. Along with lethal effects, sublethal doses of EPF reduced the number of egg pods per female, total eggs per pod, and egg hatching, while extending nymphal developmental time and reducing adult longevity; again, Green Muscle performed better. Sublethal doses not only retarded reproduction, but also caused behavioral changes, including reductions in food consumption, fecal production, and weight gain. All EPF formulations not only produced significant mortality in laboratory conditions, but also performed very well under the greenhouse and field conditions. The maximum mortality against 3rd-instar (81.7% and 74.0%), 5th-instar (73.3% and 65.1%), and adult locusts (67.5% and 58.9%) was observed when using Green Muscle under greenhouse and field trials, respectively. The current study showed that all of the EPF formulations have the potential to reduce pest populations, and could be used in the integrated pest management program. [ABSTRACT FROM AUTHOR]

Glyphosate is an herbicide which was previously considered safe for non-target organisms. 825.8 million kilograms of glyphosate-based products were used globally in 2014. The toxicity of pure glyphosate is well known, yet there is little information on the toxicity of glyphosate products, which contain other compounds that may increase or decrease toxicity. Here we studied the effects of different glyphosate-based formulations on the predatory activity of wolf spiders Pardosa against flies. We measured the number of dead flies after direct spider contact with seven commercial glyphosate-based formulations. We found that Roundup® Klasik pro affected predatory activity in the short term. For long-term predatory activity, the number of dead flies increased slower in the cases of application of Roundup® Klasik pro and Touchdown Quattro®. Our results support the hypothesis that various pesticide formulations with the same active ingredient have different effects on predators. Therefore, approval authorities should take formulation toxicity into account to give preference to more environmentally friendly products. [ABSTRACT FROM AUTHOR]

Background: There is a pressing need to improve understanding of how insecticide resistance affects the functional performance of insecticide-treated nets (ITNs). Standard WHO insecticide resistance monitoring assays are designed for resistance surveillance and do not necessarily provide insight into how different frequencies, mechanisms or intensities of resistance affect the ability of ITNs to reduce malaria transmission. Methods: The current study presents some novel laboratory-based assays that attempt to better simulate realistic exposure of mosquitoes to ITNs and to quantify impact of exposure not only on instantaneous mortality, but also on blood-feeding and longevity, two traits that are central to transmission. The assays evaluated the performance of a standard ITN (Permanet® 2.0; Vestergaard Frandsen), a 'next generation' combination ITN with a resistance-breaking synergist (Permanet® 3.0) and an untreated net (UTN), against field-derived Anopheles gambiae sensu lato mosquitoes from Côte d'Ivoire exhibiting a 1500-fold increase in pyrethroid resistance relative to a standard susceptible strain. Results: The study revealed that the standard ITN induced negligible instantaneous mortality against the resistant mosquitoes, whereas the resistance-breaking net caused high mortality and a reduction in blood-feeding. However, both ITNs still impacted long-term survival relative to the UTN. The impact on longevity depended on feeding status, with blood-fed mosquitoes living longer than unfed mosquitoes following ITN exposure. Exposure to both ITNs also reduced the blood-feeding success, the time spent on the net and blood-feeding duration, relative to the untreated net. Conclusion: Although a standard ITN did not have as substantial instantaneous impact as the resistance-breaking net, it still had significant impacts on traits important for transmission. These results highlight the benefit of improved bioefficacy assays that allow for realistic exposure and consider sub- or pre-lethal effects to help assess the functional significance of insecticide resistance. [ABSTRACT FROM AUTHOR]

The suppression of pest populations by a predator depends on two basic components of the predator-prey interaction: the functional and the numerical responses of the predator. Such responses can be affected by exposure to acaricides. In the present study, the effects of acaricides (abamectin, azadirachtin, fenpyroximate, and chlorfenapyr) on the functional and numerical responses of the predatory mite, Amblyseius largoensis (Acari: Phytoseiidae) an important natural enemy of the pest mite, Raoiella indica (Acari: Tenuipalpidae), were investigated. The exposure of A. largoensis to acaricides occurred through contact with a surface contaminated with dried acaricide residue. Subsequently, A. largoensis exhibited a type II functional response, which was not altered by exposure of any acaricides. However, exposure to abamectin resulted in a decrease in the average mean numbers of prey consumed by a predator. Exposure to acaricides increased prey handling time by 67%, 25%, 38%, and 35% for abamectin, azadirachtin, fenpyroximate, and chlorfenapyr, respectively. Exposure to abamectin reduced the attack rate of A. largoensis by 52%. The numerical response of A. largoensis was only affected by exposure to abamectin, where just 60% of the females oviposited, and regardless of the prey density, the average mean numbers of eggs/female/day was always less than 0.4. The food conversion efficiency into biomass of A. largoensis eggs decreased with increasing prey density, and this trend was not altered by exposure to any acaricides. However, exposure to abamectin drastically compromised the oviposition of A. largoensis, showing no increase in egg production with increasing prey density. [ABSTRACT FROM AUTHOR]

Tetranychus truncatus Ehara (Acari: Tetranychidae) is one of the serious pests that infests different agricultural crops in field and greenhouse crops, and its distribution is limited to mostly Asian countries. The experiments were conducted to know the effectiveness of different concentrations of bifenazate against the T. truncatus, and to evaluate and compare the demographic parameters of T. truncatus on host plant Lablab purpureus (L.) Sweet (Fabaceae), which were obtained from females treated with bifenazate. The LC15, LC30, LC50 and LC90 values are determined through the bioassay from the results of the first application of bifenazate on adult females of T. truncatus. The LC15, LC30, LC50 and LC90 concentrations of bifenazate were 0.417, 1.028, 2.591 and 24.792 ml/ l, respectively. The response of adult females against the two lethal concentrations (LC15 and LC30) was mostly alike but had a little bit difference. The differences in life table parameters were observed between control and treated spider mites. The results demonstrated that LC15 and LC30 of bifenazate could reduce the survival rate, oviposition period, fecundity and longevity of females of T. truncatus and it significantly affected the developmental times, especially larval duration and fecundity of T. truncatus. Life-table parameters of T. truncatus were much reduced in LC15 and LC30 compared to the control and their growth and other factors showed significant differences. The present study showed that the lower lethal concentration (LC15 and LC30) of the tested acaricide showed negative effects on survivorship and life-table parameters of the subsequent generation of T. truncatus. [ABSTRACT FROM AUTHOR]

We evaluated the accumulation of okadaic acid (OA), a diarrhetic toxin, and the antioxidant responses in the marine annelid Laeonereis acuta exposed to the benthic toxigenic dinoflagellate Prorocentrum cf. lima. Nontoxic Tetraselmis sp. was used as a control diet. Living cells of the two algae were supplied as food to animals kept in agar medium for 72 h. To assess the significance of the observed effects, our experimental design treated the algal species (diet), algal cell densities, and exposure time as fixed factors. Responses of the organisms were assessed through oxidative stress biomarkers (glutathione-S-transferase [GST], catalase [CAT], reduced glutathione [GSH] and lipid peroxidation [LPO]). Toxin accumulation was measured by LC-MS/MS in whole-body homogenates after 12, 24 and 72 h of exposure. Worms exposed to the toxigenic dinoflagellate gradually accumulated OA, with toxin levels directly related to the cell density of Prorocentrum cf. lima. Worms fed with Prorocentrum cf. lima exhibited decreased CAT activity, increased LPO levels – both interactively affected by algal species and time – and decreased GSH levels, which were interactively affected by algal species and cell density. Higher LPO levels, along with the inhibition of CAT and GSH, clearly indicated an oxidative stress situation in worms exposed to the toxigenic dinoflagellate. Laeonereis acuta accumulated moderate OA levels and may act as a vector of OA to food webs in estuarine areas under high Prorocentrum cf. lima abundance. [Display omitted] • We assessed the negative effects of Prorocentrum cf. lima on the annelid Laeonereis acuta. • Accumulation of okadaic acid by L. acuta was directly related to exposure time and cell density. • Antioxidant responses depended on the exposure time and algal cell density. • We propose gelled agar as a cultivation medium in ecotoxicological assays. • Annelids can be vectors of okadaic acid to their consumers, posing a risk to marine fauna and human health. [ABSTRACT FROM AUTHOR]

The fall armyworm Spodoptera frugiperda is a one of the most invasive and damaging pests that causes serious economic losses in several crops. Botanical insecticides such as tea saponin and matrine, as environmentally acceptable biopesticides, are widely used for controlling pests. Insecticide stress affects both individuals and the associated bacteria in insects. However, it remains unclear that if sublethal effects and bacteria are the drivers for the adaptive mechanisms of insecticides in fall armyworm. We examined the effectiveness of a 10:1 v/v mixture of biological insecticides against the fall armyworm and the impacts of several biological parameters and demographic variables of the armyworm targeting two generations at primary exposure. Moreover, the influence of the insecticide mixture on the associated bacteria of the fall armyworm was assessed via 16 S rRNA sequencing. The results showed that the mixture was highly toxic to fall armyworms, and the fecundity of the initially exposed generation (F 0) significantly decreased; however, there was no significant effect on longevity. The larval duration, the total pre-reproductive period, longevity, fecundity, and mean generation time of the fall armyworm in the F 1 significantly increased; yet the intrinsic and finite rates of the increase and the net reproductive rate remained fairly constant. Additionally, the population of associated bacteria was affected in both generations, with an increase in the microbial diversity within the fall armyworm compared to that of the F 0 generation. Also, an increase in abundance of several genera of bacteria, including Acinetobacter , Serratia , Enterococcus , and Pseudomonas , was noted following treatment with the insecticide mixture. These results broaden our understanding of the impact of sublethal insecticide concentrations on the fall armyworm and its associated bacterial community. [Display omitted] • Decreased F 0 fecundity was observed after maternal exposure to sublethal concentration of biopesticides. • Transgenerational effect of biopesticides promoted F 1 fecundity after maternal exposure but not lead to the booming of population. • The community microflora of associated bacteria was altered in two generations after maternal exposure. [ABSTRACT FROM AUTHOR]

Dubas bug, Ommatissus lybicus de Bergevin (Hemiptera: Tropiduchidae), is one of the most important pests of date palm (Phoenix dactylifera L.) in Iran. In the present study, the lethal and sublethal effects of commercial formulations of acetamiprid, clothianidin, diflubenzuron, Eforia® (thiamethoxam+lambda-cyhalothrin), and fenitrothion on O. lybicus were examined. The concentrations of tested insecticides were predetermined by concentration-setting experiments based on a logarithmic scale. Stock solutions of the compounds were prepared by diluting the stock solution in Triton X-100 (0.1%) in distilled water. Triton X-100 (0.1%) in distilled water was used as control. Among insecticides tested, Eforia and fenitrothion were the more toxic to O. lybicus adults with the LC50s of 7.2 and 9.4 mg/L. The sublethal effects of Eforia were assessed by treating O. lybicus adults with the LC10 (3.7 mg/L), LC30 (4.8 mg/L), and LC50 (7.2 mg/L). The significant differences were not found for nymphal development and fecundity in LC10 concentration (73.51 d and 86.24 eggs/female, respectively) compared to control (73.78 d and 84.52 eggs/female, respectively). However, a significant reduction in survival and growth rate was observed in this concentration. The longevity and fecundity of females exposed to LC30 and LC50 concentrations were reduced. At LC30 and LC50 concentrations, Eforia prolonged the developmental duration (80.91 and 84.08 d, respectively) and decreased the survival rate (54.3 and 33.7%, respectively) of immature stages of O. lybicus. Furthermore, the quantity of food assimilated by O. lybicus on the date palm was significantly reduced at the LC30 and LC50 concentrations (1.67 and 1.34 mg, respectively). Altogether, these results indicate that Eforia could be useful for the management of O. lybicus population in Iran. [ABSTRACT FROM AUTHOR]

Tetranychus urticae Koch (Acari: Tetranychidae) is a notorious crop pest with a worldwide distribution that has developed resistance to a wide range of acaricides. Combined tactics of pest management have special significance not only for a reduction in pesticide residues but also to maintain the natural enemy activity, which is an objective of IPM programs. Here, we investigated the effect of low-lethal concentrations of bifenazate at LC10, LC20, and LC30 on development and reproduction parameters of Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae). Lethal and sub-lethal concentrations were estimated using leaf dip bioassay method. The crude data were analyzed based on age-stage, two-sex life table analysis. Toxicological assays showed bifenazate treatments gradually decreased the longevity and total life span of both sexes. Our results indicated that reproductive and total fecundity of the next generation were also affected by sublethal concentrations. All concentrations caused a significant decline in oviposition days, compared to the control. The intrinsic rate of increase (rm) varied from 0.1344 to 0.1151 day-1 for the mites treated with distilled water and LC30 treatments, respectively. The finite rate of increase (λ) was affected by the acaricide concentration (lowest at LC30 concentration: 1.1221 day-1). Bifenazate concentration (LC10, LC20 and LC30) treatments gradually reduced the gross reproduction rate (GRR) and net reproductive rate (R0). Based on obtained results from current study, bifenazate is not a favorable acaricide with A. swiriskii and cannot be recommended to use with this predatory mite in integrated management. [ABSTRACT FROM AUTHOR]

[Objectives] The study aimed to understand the resistance status of Ostrinia furnacalis populations from Xinjiang to chlorantraniliprole( CAP) and effects of Asian corn borer treated by chlorantraniliprole on the activities of three detoxifying enzymes,including esterase (EST), glutathione 5-transferase ( GST) and cytochrome P450 enzyme ( P450), and population breeding. [Methods] The susceptibilities to chlorantraniliprole of the populations collected from Urumqi, Yining, Shule and Zepu in Xinjiang, were determined using topical application. 3rd instar larvae of O.furnacalis were treated with LD20 and LD50 dose of chlorantraniliprole for 72 h and selected continuously for 9 generations with LD50 dose of chlorantraniliprole( CAP-Sel). The activities of detoxification enzymatic were analyzed by in vitro enzyme activity assay in different treatments and populations of O.furnacalis and the development of tested insects was observed. [ Results] Compared with the relative susceptible population Urumqi, Shule and Zepu populations had decreased sensitivity to chlorantraniliprole with resistance ratio of 4.0- and 4.2-folds,respectively. The highest activity of P450 was detected in Yining population, while GST ( DCNB as substrate) activity of Shule population was the highest among the tested populations. The activities of GST ( DCNB as substrate) in the LD20 and LD50 treatment groups for 72 h increased significantly by 1.46- and 1.86-folds compared with the control respectively. Futhermore, the activities of the three detoxification enzymes in CAP-Sel strain were promoted along with the increase of generations and the change of P450 activities were the most significant, which in the F5 and F8 generations were enhanced by 4.27- and 5.09-folds,meanwhile, the activities of GST( CDNB as substrate) in F5 and F8 generations and GST( DCNB as substrate) in the F8 generation were increased by 1.27-.1.33- and 1.36-folds compared to those in susceptible strain, respectively. The sublethal dose( LD20) of chlormitraniliprole for 72 h significantly lowered the weight of pupae and feeundity of O.furnacalis. The larval period with prolonged and the pupal weight mid adult emergence rate increased significantly in F 10 generation of CAP-Sel strain compared to that in the susceptible strain. And the CAP-Sel strain had fewer number of eggs and hatching rate than susceptible strain by 14.83% and 5.84%. The intrinsic rate of increase ( r) and net reproductive rate ( R0 ) of CAP-Sel strain were significantly lower than those in the susceptible strain with 0.14 and 0.16, 17 .22 mid 20.33, respectively. [Conclusions] Based on the above results, it was found that the Asian corn borer in Xinjiang was developing risk of resistance to chlorantraniliprole. The treatment of chlorantraniliprole can significantly restrain the growth,md development of O.furnacalis P450 and GST may he the major detoxication enzyme on the metabolic detoxification of chlorantraniliprole in the O.furnacalis and involved in the formation of resistance. [ABSTRACT FROM AUTHOR]

Entomopathogenic bacteria occupy a special place in the natural regulation of many insects. It is mainly the species of the genus Bacillus that is mostly used in biological pest control and offers encouraging prospects. We have studied in the laboratory the sublethal effect of an indigenous bacterial strain from a coastal region in central Algeria, on some life parameters of the date palm moth Ectomyelois ceratoniae, a potential pest of palm groves in Algeria. The bacterium was identified on the basis of a molecular study by sequencing the 16s RNA. The characterisation was carried out on the basis of its morphology and certain physiological and biochemical criteria. The bacterial isolate showed different reactions to the identification tests carried out with the ability to degrade several substrates such as lipids, proteins and complex sugars as well as chitin, gelatin and cellulose. The phylogenetic study confirmed that the bacterium belongs to the genus Bacillus with a high percentage of similarity for Bacillus thuringiensis. Biological activity of the bacterium was tested for food intake, pupation and emergence rates in mature caterpillars (L4 and L5) of both male and female sexes of the moth of the date over a 22-day period. The results obtained show a significant decrease in the three studied parameters, which is all the more important in female larvae than in male larvae, under the effect of the different tested doses (D1, D2 / l, D3, D4 et D5) compared with controls. The amount of food ingested gradually increases from the 1st to the 5th day then it tends to decrease and the caterpillars stop feeding much earlier than the controls. The pupation and emergence rates of treated caterpillars remain low, not exceeding 40%. [ABSTRACT FROM AUTHOR]

Knowledge of the impact of acaricides on predatory mites is crucial for integrated pest management (IPM) programs. The sublethal effect of propargite was assessed against the subsequent generation of treated Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) fed on Tetranychus urticae Koch (Acari: Tetranychidae) under laboratory conditions [26 ± 1 °C, 70 ± 3 % RH and 16:8 (L:D) h]. A leaf disc bioassay was employed to assess the sublethal concentrations (LC10, LC20, and LC30) of propargite (Omite® 57% EC, MAHAN, Iran) on A. swirskii. The results revealed that sublethal concentrations of propargite significantly affected the total life span and longevity of the treated females of A. swirskii. Reproductive and total fecundity of the subsequent generation were also affected by sublethal concentrations. All concentrations caused a significant reduction in oviposition days, compared to the control. The intrinsic rates of increase (r) of A. swirskii treated with sublethal concentrations of propargite and distilled water were 0.126, 0.122, 0.115, and 0.129 d-1, respectively. Our findings revealed that propargite had no significant effect on life table parameters of treated mites in comparison to the control. Sublethal effects of propargite and its impact on A. swirskii are discussed. [ABSTRACT FROM AUTHOR]

The goal of our study was to determine if phosphine exposure changed the fecundity of the surviving Liposcelis entomophila, and the fitness of resulting offspring. Two strains of L. entomophila, were tested. One (F0) that had not been exposed to phosphine in the laboratory, and a second (F4) that had been exposed to the LC50 dose of phosphine for 4 successive generations. The daily egg production, rate of growth, hatching rate, sex ratio, and adult emergence rate were measured after exposures to phosphine at the LC20 and LC50 doses. LC20 fumigation did not affect peak oviposition and fumigation at LC50 dose delayed peak oviposition peak in F0. Females fumigated at LC20 dose had higher fecundity in the first oviposition peaks from 3rd day. The accumulated egg production of F4 fumigated at LC20 and LC50 was significantly higher than that of F0 in the first and second weeks. All the results indicated that long term fumigation with sublethal LC20 could stimulate the surviving females to lay more eggs. Fumigation at LC50 dose could inhibit female fecundity and progeny population growth. The results suggested that long-term fumigation with LC20 could induce strong population growth and lead to L. entomophila infestations. [ABSTRACT FROM AUTHOR]

Knowledge of the effects of pesticides on biological control agents is necessary for the successful implementation of integrated pest management programs. Laboratory bioassays were conducted to evaluate the effects of Biomite®, a natural acaricide, on the life table parameters of Neoseiulus californicus McGregor (Acari: Phytoseiidae), as one of the most important natural enemies of Tetranychus urticae Koch (Acari: Tetranychidae) under laboratory conditions at 25 ± 2°C, 65 ± 5% RH and a photoperiod of 16:8 (L:D) h. The raw data were analyzed based on the two-sex life table theory. Biomite® concentrations LC10 and LC20 gradually and significantly reduced the longevity and total life span of both sexes, as well as total fecundity. Besides, concentration LC20 significantly reduced the gross reproductive rate (GRR) and the net reproductive rate (R0). However, the intrinsic rate of increase (r) and the finite rate of increase (λ) were not significantly affected. Thereby, due to an unfavorable shortened in life history characters of N. californicus such as total life span, reproductive periods and biological parameters (such as R0 and GRR), as a consequence of Biomite® treatment, it can be concluded that this acaricide should not be used with N. californicus in integrated pest management programs. [ABSTRACT FROM AUTHOR]

The anthranilic diamide insecticide chlorantraniliprole was widely used for the controlling of Chilo suppressalis in China. Previous studies have revealed sublethal effects of chlorantraniliprole on the development and reproduction of C. suppressalis. In the present study, a comparative transcriptome analysis was performed to investigate the global gene expression changes in third-instar larvae of C. suppressalis after exposure to LC 30 of chlorantraniliprole. A total of 908 differentially expressed genes (DEGs) were identified including 441 up-regulated and 467 down-regulated unigenes. Gene enrichment analysis revealed that the down-regulated DEGs were mainly linked to carbohydrate, energy, lipid and amino acid metabolisms as well as posttranslational modification, while most of the DEGs involved in signal transduction were up-regulated. Specifically, the DEGs encoding detoxification related genes were identified and validated by RT-qPCR. Our results provide a basis for understanding the molecular mechanisms of chlorantraniliprole action and detoxification in C. suppressalis and other insect pests. Image 1 • A comparative transcriptome analysis was performed in C. suppressalis after exposure to LC 30 of chlorantraniliprole. • The DEGs were significantly enriched in metabolisms, posttranslational modification and signal transduction mechanisms. • The DEGs encoding detoxification related genes were identified and validated by RT-qPCR. [ABSTRACT FROM AUTHOR]

The whitefly, Aleuroclava jasmini (Takahashi) (Hemiptera: Aleyrodidae), is an important pest on paper mulberry Broussonetia papyrifera (L.) Vent. (Moraceae) plants in green spaces of Tehran, Iran. The predator mite Amblyseius swirskii Athias-Henriot is one of the most common species found in paper mulberry landscape and it is a major biological control agent of this pest. Knowledge of the impact of insecticides on predatory mites is crucial for integrated management programs of this whitefly. This study assessed, under laboratory conditions, the sublethal effect of acetamiprid on the life table parameters of A. swirskii fed on A. jasmini. The sublethal concentrations LC10, LC20 and LC30 were obtained based on a dose-effect test. Exposure to the sublethal concentrations of acetamiprid had significant effects on the total immature periods of both males and females. The total fecundity and oviposition period decreased with an increase in concentration. The estimated life table parameters indicated that sublethal concentrations of acetamiprid caused greater reduction in r, λ and R0 of A. swirskii compared to the control. Therefore, the use of acetamiprid to control of A. jasmini may have serious implications for integrated pest management programs that aimed at exploiting A. swirskii biological control in paper mulberry landscape. [ABSTRACT FROM AUTHOR]

Sogatella furcifera (Horváth) is one of the most important migratory pests of rice in Asia. When normal concentrations of deltamethrin are applied to control lepidopteran pests of rice in the field, it is likely that S. furcifera will be exposed to sublethal concentrations of this chemical. Therefore, we examined the sublethal effects of deltamethrin on the development and reproduction of S. furcifera using the rice stem dipping method. The results showed that exposure of 3rd instar S. furcifera to LC10 and LC25 deltamethrin significantly increased the emergence rates compared with the F0 generation control group, but there was no significant difference in the nymphal stage duration, adult longevity and female fecundity. Nymphal duration of the F1 generation was significantly prolonged under both treatments. Female fecundity also increased in this generation, with a significant difference between the LC25 treatment group and controls. The relative fitness of the LC10 and LC25 treatment groups was 0.84 and 0.80, respectively. The results showed that sublethal concentrations of deltamethrin stimulate the reproduction of S. furcifera, but decrease the relative fitness of the population. These results provided a reference point for the application of insecticides to control S. furcifera. [ABSTRACT FROM AUTHOR]

The citrus red mite, Panonychus citri (McGregor), is a globally important pest that has developed severe resistance to various pesticides. Lufenuron has been widely used in the control of the related pests in citrus orchard ecosystem. In this study, the susceptibilities of egg, larva, deutonymph and female adult of P. citri to lufenuron was determined, and the LC 50 values were 161.354 mg/L, 49.595 mg/L, 81.580 mg/L, and 147.006 mg/L, respectively. Life-table analysis indicated that the fecundities were significantly increased by 11.86% and 26.84% after the mites were treated with LC 20 concentrations of lufenuron at the egg or deutonymph stages, respectively. After eggs were treated with lufenuron, the immature stage and longevity were also affected, and resulted in a significant increase in r , R 0 and λ. After exposure of female adults to LC 20 of lufenuron, the fecundity and longevity of F 0 generation significantly decreased by 31.99% and 10.94%, respectively. Furthermore, the expression level of EcR and Vg was significantly inhibited upon mites was treated with lufenuron. However, lufenuron exposure has a positive effect on fecundity and R 0 in F 1 generation, the expression of all reproduction-related genes was significantly up-regulated. In conclusion, there was a stimulating effect on the offspring population. Our results will contribute to the assessment of the resurgence of P. citri in the field after the application of lufenuron and the development of integrated pest control strategies in citrus orchards. [Display omitted] • Lufenuron exhibited higher toxicities to larvae and deutonymph of Panonychus citri. • Eggs/deutonymphs exposure to LC 20 of lufenuron significantly stimulated reproduction. • Exposure of female adults to lufenuron had a hormesis effect on F 1 generation. • Fecundity difference caused by lufenuron was related to the JHAMT , JHBP and USP genes. [ABSTRACT FROM AUTHOR]

• Impact of metconazole and thiacloprid was evaluated on the mobility and activity behavior of Hyalella azteca. • Change from additive effects to synergism in the mobility tests for sediment with higher contents of total carbon. • Sediments with high carbon, nitrogen and phosphorous contents led to comparable activity behavior of H. azteca to control conditions. • This study showed that pesticide effects on mobility and activity of H. azteca are largely mediated by the structure of the sediment. Pesticide mixtures occur frequently in freshwaters. Here, pesticides can persist over long periods and alter aquatic communities and ecosystems by causing chronic indirect effects. Particularly effects on activity behavior of organisms can be considered as starting points of cascading effects as they provide the basis for further sublethal responses such as reproduction or feeding. Therefore, the impact of two pesticides in combination, the fungicide metconazole and the insecticide thiacloprid, was evaluated on the immobilization and activity behavior of Hyalella azteca with varying sediment conditions. The results showed a change from additive effects to synergism in the mobility tests for sediment with higher contents of total carbon but not for the activity behavior tests using a Multispecies Freshwater Biomonitoring system. However, sediments with high carbon, nitrogen and phosphorous contents led to comparable activity behavior of H. azteca to control conditions after three days of contaminant exposure which was not the case in all other treatments. The autoregressive integrated moving average (ARIMA) forecast approach used showed that this activity behavior remained constant after recovery to pre-exposure levels at least for a time period of 16 h. This study showed that mobility and activity of H. azteca are largely affected by the exposure to pesticides, which is mediated by the structure of the sediment. However, further studies are needed that test activity behavior impairments in environments where the individuals are in direct contact with the sediment that may buffer the pesticide exposure from the water column. [ABSTRACT FROM AUTHOR]