Acute lethal and sublethal effects of four insecticides on the lacewing (Chrysoperla sinica Tjeder)

Abamectin exposure causes chronic toxicity and trypsin/chymotrypsin damages in Chironomus kiiensis Tokunaga (Diptera: Chironomidae)

Abamectin has been extensively used in paddy fields to control insect pests. However, little information is available regarding its effects on non-target insects. In this study, we performed acute (3rd instar larvae) and chronic toxicity (newly hatched larvae <24 h) to determine the toxicity effects of abamectin on Chironomus kiiensis. The median lethal concentration (LC50) values of 24 h and 10 d were 0.57 mg/L and 68.12 μg/L, respectively. The chronic exposure significantly prolonged the larvae growth duration and inhibited pupation and emergence. The transcriptome and biochemical parameters were measured using 3rd instar larvae exposed to acute LC10 and LC25 for 24 h. Transcriptome data indicated that five trypsin and four chymotrypsin genes were downregulated, and RT-qPCR verified a significant expression decrease in trypsin3 and chymotrypsin1 genes. Meanwhile, abamectin could significantly inhibit the activities of the serine proteases trypsin and chymotrypsin. RNA interference showed that silencing trypsin3 and chymotrypsin1 genes led to higher mortality of C. kiiensis to abamectin. In conclusion, these findings indicated that trypsin and chymotrypsin are involved in the abamectin toxicity against C. kiiensis, which provides new insights into the mechanism of abamectin-induced ecotoxicity to chironomids.

JH degradation pathway participates in hormonal regulation of larval development of Bombyx mori following λ-cyhalothrin exposure

λ-Cyhalothrin (λ-cyh), a widely utilized pyrethroid insecticide, poses serious threats to non-target organisms due to its persistence nature in the environment. Exposure to low concentrations of λ-cyh has been observed to result in prolonged larval development in Bombyx mori, leading to substantial financial losses in sericulture. The present study was undertaken to elucidate the underlying mechanisms for prolonged development caused by λ-cyh (LC10) exposure. The results showed that the JH Ⅲ titer was significantly increased at 24 h of λ-cyh exposure, and the JH interacting genes Methoprene-tolerant 2, Steroid Receptor Co-activator, Krüppel-homolog 1, and JH binding proteins were also up-regulated. Although the target of rapamycin (Tor) genes were induced by λ-cyh, the biosynthesis of JH in the corpora allata was not promoted. Notably, 13 JH degradation genes were found to be significantly down-regulated in the midgut of B. mori. The mRNA levels and enzyme activity assays indicated that λ-cyh had inhibitory effects on JH esterase, JH epoxide hydrolase, and JH diol kinase (JHDK). Furthermore, the suppression of JHDK (KWMTBOMO01580) was further confirmed by both western blot and immunohistochemistry. This study has offered a comprehensive perspective on the mechanisms underlying the prolonged development caused by insecticides, and our results also hold significant implications for the safe production of sericulture.

Sublethal effects of acetamiprid and afidopyropen on Harmonia axyridis: insights from transcriptomics analysis

Evaluating the sublethal effects of insecticide is crucial for protecting and utilizing natural enemies. In this study, we determined the sublethal effects of acetamiprid and afidopyropen on Harmonia axyridis (Pallas) and explored the potential molecular mechanisms underlying these effects through transcriptomics analysis. The results showed that sublethal concentrations of acetamiprid significantly reduced the adult fecundity and longevity of F₀H. axyridis and decreased the survival time and survival rate of the F₁ generation. Sublethal concentrations of afidopyropen prolonged the developmental time of 4th instar larvae in the F₀ generation. Additionally, acetamiprid and afidopyropen treatments significantly decreased the predation of H. axyridis. Furthermore, transcriptome sequencing analysis revealed that several P450 and UGT genes expressed differently when H. axyridis were exposed to sublethal concentrations of acetamiprid and afidopyropen, suggesting that the differential expression of detoxifying genes might be involved in the response and detoxification metabolism of acetamiprid and afidopyropen in H. axyridis. Our findings demonstrate that sublethal concentrations of acetamiprid adversely influences the development and predation of H. axyridis, while afidopyropen has limited effects on H. axyridis. These results are helpful for protecting and utilizing natural enemies and guiding the scientific use of pesticides in the field.

Predatory stink bug, Eocanthecona furcellata (Wolff) responses to oral exposure route of λ-cyhalothrin via sex-specific modulation manner

The toxic effects of insecticides on predatory arthropods have closely related to their exposure routes. However, little is known about the effects of insecticide on reproductive parameters when the route of exposure occurs at a trophic level via prey intake. We therefore conducted current studies assessing whether Eocanthecona furcellata adults would be affected by feeding with λ-cyhalothrin-contaminated prey. Reproductive parameters, i.e. prolonged premating and preoviposition durations, reduced number of egg batches and egg amount, disturbed ovarian development, and suppressed expression of reproductive related genes were observed in E. furcellata females by feeding with treated prey. Moreover, reduced survival rate and altered carbohydrate metabolism parameters were detected in male bugs. Biochemical parameters, including MDA content, the activities of three antioxidant enzymes and three detoxification enzymes exhibited sex-specific responses after oral-exposure to λ-cyhalothrin in E. furcellata. The results indicate that the insecticide affects the fitness and leads to impairing reproductive potential via sex-specific modulation manner in predator insects. Taken together, our results provide a comprehensive assessment about detrimental impacts of λ-cyhalothrin-exposure on predators via prey intake, as well as a solid basis for further research to protect the predators from hazardous impacts of insecticides.

Sublethal Effects of Neonicotinoid Insecticides on the Development, Body Weight and Economic Characteristics of Silkworm

Silkworm Bombyx mori (L.) (Lepidoptera: Bombycidae) is a critical insect for silk producers, but the inappropriate application of insecticides negatively affects the physiology and behavior of silkworms. This study found that the effects of neonicotinoid insecticides applied using two spraying methods on the growth and development of silkworms were different: the median lethal concentration (LC₅₀) values of two pesticides applied using the leaf-dipping method were 0.33 and 0.83 mg L^-1 and those of two pesticides applied using the quantitative spraying method were 0.91 and 1.23 mg kg^-1. The concentration of pesticides on the mulberry leaves did not decrease after their application using the quantitative spraying method, and a uniform spraying density was observed after the mulberry leaves were air-dried (no liquid) under realistic conditions. We then treated silkworms with the quantitative spraying method and leaf-dipping method. The treatment of silkworm larvae with imidacloprid and thiamethoxam at sublethal concentrations significantly prolonged the development time and significantly decreased the weight and pupation rate, as well as economic indicators of enamel layers and sputum production. Thiamethoxam treatment significantly increased the activities of carboxylesterase (CarE) and glutathione-S-transferase (GST). The activity of CarE and GST increased, decreased, and then increased, and the highest activity was detected on the 10th and 12th days. Thiamethoxam exposure significantly elevated the transcription levels of CarE-11, GSTe3 and GSTz2 and induced DNA damage in hemocytes. This study confirmed that the quantitative spray method is more stable than the leaf-dipping method. Moreover, imidacloprid and thiamethoxam treatment affected the economy and indexes of silkworms and induced changes in detoxification enzymes and DNA damage in silkworms. These results provide a basis for understanding the mechanism of the sublethal effects of insecticides on silkworms.

Characterization of the sublethal toxicity and transcriptome-wide biological changes induced by λ-cyhalothrin in Bombyx mori

λ-Cyhalothrin (λ-cyh) is widely used in agricultural production and has been reported to cause damages to numerous nontarget insects. As an important economic and model insect of Lepidoptera, Bombyx mori was extremely sensitive to λ-cyh, and pesticide drift often leads to silkworm poisoning. However, little is known about the persistence of sublethal effects or the potential recovery from short-term exposure to sublethal doses of pesticides. In this study, we estimated the sublethal effects caused by short-term exposure (24 h) of λ-cyh LC₁ , LC₁₀ , LC₂₅ , and LC₅₀ , respectively, and investigated the persistent negative effects on the growth, survival, and pupal metamorphosis of silkworm larvae. Silkworm growth was mostly retarded after λ-cyh exposure, with dose-dependent recovery observed at delayed time points. Relative to the control, the treatment groups showed significantly higher larval mortalities and abnormal pupa rates. Additionally, transcriptome sequencing was conducted to investigate the effects of λ-cyh LC₁₀ on the normal physiological functions in the midgut of B. mori. A total of 2697 differentially expressed genes were identified, and 57.1% of DEGs were down-regulated. Gene ontology and Kyoto encyclopedia of genes and genomes enrichment analysis further revealed that energy and nutrient metabolisms were negatively affected. Moreover, we demonstrated that sublethal λ-cyh inhibited the oxidative phosphorylation pathway by reducing the expression of mitochondrial electron transport chain complex genes and consequently the synthesis of ATP. This study has provided useful transcriptome-wide expression resources to facilitate the overall knowledge of the molecular basis of sublethal toxicity caused by λ-cyh in the midgut of B. mori.

Sublethal effects of chlorantraniliprole on growth, biochemical and molecular parameters in two chironomids, Chironomus kiiensis and Chironomus javanus

Pesticide residues have serious environmental impacts on rice-based ecosystems. In rice fields, Chironomus kiiensis and Chironomus javanus provide alternative food sources to predatory natural enemies of rice insect pests, especially when pests are low. Chlorantraniliprole is a substitute for older classes of insecticides and has been used extensively to control rice pests. To determine the ecological risks of chlorantraniliprole in rice fields, we evaluated its toxic effects on certain growth, biochemical and molecular parameters in these two chironomids. The toxicity tests were performed by exposing third-instar larvae to a range of concentrations of chlorantraniliprole. LC₅₀ values at 24 h, 48 h, and 10 days showed that chlorantraniliprole was more toxic to C. javanus than to C. kiiensis. Chlorantraniliprole significantly prolonged the larval growth duration, inhibited pupation and emergence, and decreased egg numbers of C. kiiensis and C. javanus at sublethal dosages (LC₁₀ = 1.50 mg/L and LC₂₅ = 3.00 mg/L for C. kiiensis; LC₁₀ = 0.25 mg/L and LC₂₅ = 0.50 mg/L for C. javanus). Sublethal exposure to chlorantraniliprole significantly decreased the activity of the detoxification enzymes carboxylesterase (CarE) and glutathione S-transferases (GSTs) in both C. kiiensis and C. javanus. Sublethal exposure to chlorantraniliprole also markedly inhibited the activity of the antioxidant enzyme peroxidase (POD) in C. kiiensis and POD and catalase (CAT) in C. javanus. Expression levels of 12 genes revealed that detoxification and antioxidant abilities were affected by sublethal exposures to chlorantraniliprole. There were significant changes in the expression levels of seven genes (CarE6, CYP9AU1, CYP6FV2, GSTo1, GSTs1, GSTd2, and POD) in C. kiiensis and ten genes (CarE6, CYP9AU1, CYP6FV2, GSTo1, GSTs1, GSTd2, GSTu1, GSTu2, CAT, and POD) in C. javanus. These results provide a comprehensive overview of the differences in chlorantraniliprole toxicity to chironomids, indicating that C. javanus is more susceptible and suitable as an indicator for ecological risk assessment in rice ecosystems.

Sublethal effects of an indoxacarb enantiomer insecticide on Plutella xylostella caterpillar and Chrysoperla sinica predator

Plutella xylostella (L.) is a migratory species and an important insect pest of cruciferous crops worldwide, and Chrysoperla sinica (Tjeder) is a predaceous insect of agricultural and forest pests in the field. Indoxacarb has two enantiomers: (+)-S-indoxacarb and (-)-R-indoxacarb. This study was conducted to clarify the selective toxicity and sublethal effects of both enantiomers on P. xylostella and C. sinica. The (+)-S-indoxacarb isomer had greater acute toxicity to P. xylostella and C. sinica, while (-)-R-indoxacarb had less toxicity to P. xylostella and low toxicity to C. sinica. Lethal concentration 25 % (LC₂₅) of (+)-S-indoxacarb had significant effects on the development, population, and fecundity of P. xylostella and C. sinica. The LC₂₅ concentration of (-)-R-indoxacarb had a significant effect on the oviposition of P. xylostella. The field recommended concentration of (-)-R-indoxacarb significantly affected the pupal stage, adult survival rate, oviposition, and larval survival rate of C. sinica. Both enantiomers could significantly affect the search efficiency, successful attack rate, prey handling time, and maximum predation of C. sinica larvae, and the effects of (+)-S-indoxacarb alone were greater than those of (-)-R-indoxacarb. This study provided evidence of the different selective toxicity, sublethal effects of indoxacarb enantiomers on P. xylostella and C. sinica, which of the results could provide a basis for more rational use of indoxacarb in ecosystems.

Evaluation of Lethal and Sublethal Effects of Methyl Benzoate on the Generalist Predator Orius laevigatus (Fieber)

Methyl benzoate (MBe), a volatile organic molecule, has been shown to have insecticidal effects on a variety of agricultural, stored products, and urban arthropod pests in recent investigations. However, the toxicity of MBe against nontarget organisms has rarely been investigated. This study investigated the lethal and sublethal effects of MBe on the generalist predator Orius laevigatus (Fieber) (Hemiptera: Anthocoridae) via different exposure routes. This species is an important natural enemy of thrips, aphids, and mites in biological control programs globally. Acute toxicity bioassays conducted on O. laevigatus showed that the lethal median concentration (LC50) values of MBe for topical and residual toxicity were 0.73 and 0.94%, respectively, after 24 hr of exposure. Importantly, a sublethal concentration of MBe (LC30 = 0.51%) did not affect the survival and reproduction of O. laevigatus. In addition, prey consumption by O. laevigatus under different exposure conditions with varying densities of Aphis gossypii (Glover) (Hemiptera: Aphididae) adults demonstrated a good fit for a Type II functional response. The sublethal concentration of MBe did not affect the attack rate and handling time of O. laevigatus compared to untreated insects, nor did it affect the longevity and fecundity of O. laevigatus females. Thus, according to the International Organization for Biological Control, the sublethal MBe concentration for O. laevigatus is categorized as harmless and may be used in conjunction with this predator species for integrated control of many agricultural insect pests.

Transcriptome analysis of emamectin benzoate caused midgut damage by inducing oxidative stress, energy metabolism disorder and apoptosis in gypsy moth (Lymantria dispar)

BACKGROUND

Emamectin benzoate (EMB) is a semisynthetic bioinsecticide, which has been widely used in the control of forestry and agricultural pests. However, the mechanism of its toxic effects on the non-neural tissues has been rarely reported. Here, we explored the mechanism of the midgut damage induced by EMB in gypsy moth (Lymantria dispar) in order to better understand the toxicological mechanism of EMB.

RESULTS

Our results confirmed that EMB caused damage to the midgut of gypsy moth by inducing apoptosis. Transcriptome showed that 1469, 650 and 950 genes were significantly differentially expressed in the midgut of gypsy moth after 24, 48 and 72 h of EMB exposure, and oxidative stress, energy metabolism disorder and apoptosis may be related to the toxic effects of EMB. The indicators related to oxidative stress, energy metabolism and apoptosis were further examined. The results showed that EMB could cause oxidative stress by increasing ROS level and inhibiting antioxidant enzymes (P < 0.05), such as catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx), which in turn causes mitochondria injury. Subsequently, energy metabolism was inhibited by downregulating the activities and mRNA level of energy metabolism enzymes. Furthermore, the mitochondrial apoptosis pathway was activated, triggering apoptosis, and eventually causing midgut injury in gypsy moth.

CONCLUSION

Our results indicated that EMB caused damage to midgut by inducing oxidative stress, energy metabolism disorder and apoptosis in gypsy moth. Our findings shed new light on the toxicological mechanism of EMB on non-neural tissues from oxidative stress, energy metabolism and apoptosis perspectives. © 2022 Society of Chemical Industry.

Sublethal effects and reproductive hormesis of emamectin benzoate on Plutella xylostella

The diamondback moth (DBM), Plutella xylostella L., is an important pest of cruciferous vegetables, and population control mainly depends on chemical pesticides. Emamectin benzoate is a highly effective insecticide used for controlling DBM. However, it is unknown how the sublethal effects of low concentration residues of emamectin benzoate on DBM. So the population development sublethal effects of emamectin benzoate, at LC₅, LC₁₀, and LC₂₀ with concentrations of 0.014 mg/L, 0.024 mg/L and 0.047 mg/L, respectively, on adult DBM and their progeny were investigated in this study. The pupal weight, pupal period, female fecundity, and vitellin content of the F₀ DBM generation increased significantly compared to the control. And the single female oviposition number of DBM was increased by 20.21% with LC₂₀ treatment. The pupation rate, adult longevity and ovariole length of the treatment groups decreased significantly. The fecundity of DBM in the treatment groups increased, and this increased the population by a presumptive 13.84%. Treatment also led to the shortening of ovarioles and the reduction of egg hatching, and increased pupal weight in the F₁ generation. We concluded that the effects of sublethal/low concentration emamectin benzoate on the different life stages of DBM were variable, and the reproductive hormesis on DBM adults were attractive findings.

Sublethal and Transgenerational Toxicities of Chlorfenapyr on Biological Traits and Enzyme Activities of Paracoccus marginatus (Hemiptera: Pseudococcidae)

Papaya mealybug, Paracoccus marginatus Williams and Granara de Willink (Hemiptera: Pseudococcidae), is an economically important, invasive insect that is now distributed worldwide. Chlorfenapyr has been demonstrated to have a significant control effect on P. marginatus. In order to evaluate the sublethal and transgenerational effects of chlorfenapyr on P. marginatus, the life table data of three consecutive generations were collected and analyzed by the age stage, two-sex life table method, and the enzyme activities were assayed using a spectrophotometer. The results showed that exposure to the insecticide had significant effects on the biological traits of subsequent generations of P. marginatus, and a higher intrinsic rate of increase (r), finite rate of increase (λ), net reproductive rate (R₀), and a shorter mean generation time (T) were observed in the chlorfenapyr-treated F₁ mealybugs. Enzyme activity assays showed that chlorfenapyr significantly inhibited the activities of catalase (CAT) and peroxidase (POD) while activating the activities of superoxide dismutase (SOD), which suggested that SOD, CAT, and POD may play an important role in the self-defense of P. marginatus against chlorfenapyr. These results conclusively demonstrated that exposure of P. marginatus to sublethal concentrations of chlorfenapyr induced hormetic effects on the F₁ generation while having negative effects on the F₀ and F₃ generations.

Biological control for predation invasion based on pair approximation

Biological invasions have been paid more attention since invasive species may cause certain threats to local ecosystems. When biological control is adopted, selecting control species for effect better becomes the focus of latest studies. A food web system, with one native species, one invasive species as predator, and one introduced control species preying on both native and invasive species, is established based on pair approximation, in which the spatial landscape of biological invasion and control is concerned, and the local and global dispersal strategies of invasive species, in addition to the predation preferences of control species for native and invasive species, are considered. The influence of the initial density and initial spatial structures of the control species is investigated and the effects of control species releasing time are analyzed. Generally, the earlier the species introduction, the better the control effect, especially for invasive species dispersing globally. Interestingly, too low control species predation preference for native species can lead to unsuccessful introduction, while too much predation preference will have a weak control effect. The larger the control species predatory preference for invasive species is, the more conducive it is to biological control. The extinction of the invasive species is closely related to the initial density and concentration of the control species. This study gives some insights on selecting control species, its appropriate releasing time, and the density and spatial aggregation of it. Some real-life examples are elaborated on, which provides references for biological invasion control.

Evaluation of the Toxicity and Sublethal Effects of Acetamiprid and Dinotefuran on the Predator Chrysopa pallens (Rambur) (Neuroptera: Chrysopidae)

Neonicotinoid insecticides affect the physiology or behavior of insects, posing risks to non-target organisms. In this study, the effects of sublethal doses of two neonicotinoid insecticides, acetamiprid and dinotefuran, against Chrysopa pallens (Rambur) (Neuroptera: Chrysopidae) were determined and compared. The results showed that acetamiprid and dinotefuran at LD₁₀ (8.18 ng a.i. per insect and 9.36 ng a.i. per insect, respectively) and LD₃₀ (16.84 ng a.i. per insect and 15.01 ng a.i. per insect, respectively) significantly prolonged the larval stages and pupal stages (except acetamiprid LD₁₀), compared to control. In addition, acetamiprid and dinotefuran at LD₃₀ significantly prolonged the adult preoviposition period (APOP) and total preoviposition period (TPOP). In contrast, the two insecticides at LD₁₀ and LD₃₀ had no significant effect on the longevity, fecundity, reproductive days, preadult survival rate (%), intrinsic rate of increase (r), net reproductive rate (R₀), and finite rate of increase (λ). These results provide a theoretical basis for the rational use of these two insecticides and the utilization and protection of C. pallens.

Sublethal effects of tolfenpyrad on the development, reproduction, and predatory ability of Chrysoperla sinica

The lacewing, Chrysoperla sinica, is a predaceous insect that is important in crop pest management. Chemical pesticides have adversely impacted predaceous insect species. Here we studied the effect of tolfenpyrad on C. sinica. The acute toxicity of tolfenpyrad to the second-instar larvae was determined and indicated that tolfenpyrad is a medium-risk insecticide. Sublethal concentrations (LC₁₀, LC₂₀, and LC₃₀) of tolfenpyrad had effects on the development, reproduction, and predatory ability of C. sinica. When the second-instar larvae of C. sinica were exposed to sublethal concentrations of tolfenpyrad, the activities of protective enzymes, such as superoxide dismutase, peroxidase, and catalase, and detoxification enzymes, including carboxylesterase, glutathione-S-transferase, and P450 monooxygenases, were increased with exposure time. The second-instar larvae of C. sinica exposed to sublethal concentrations of tolfenpyrad exhibited an oxidative stress response that increased the levels of malondialdehyde and reactive oxygen species (ROS). Within 48-120 h after treatment, the contents of mitochondrial respiratory chain complex I and adenosine triphosphate in the second-instar larvae were decreased. This resulted in an imbalance between the production and clearance of ROS and caused cellular damage.

Characterisation of a copper/zinc superoxide dismutase from Pieris rapae and its role in protecting against oxidative stress induced by chlorantraniliprole

Insecticide exposure typically leads to abnormally high levels of reactive oxygen species (ROS) and oxidative damage in insects. Superoxide dismutases (SODs) are potent antioxidant enzymes for ROS scavenging that are essential to protect insects against insecticide-induced oxidative injury. The small white butterfly, Pieris rapae, is an economically important lepidopteran pest of cruciferous crops, and the anthranilic diamide insecticide chlorantraniliprole is widely used to control this organism. However, whether chlorantraniliprole causes oxidative stress, and whether SODs are involved in ROS scavenging, remains unclear in P. rapae. In this study, an intracellular copper/zinc SOD (designated PrSOD1) gene was identified and characterised in P. rapae. The gene consists of four exons and three introns, and the PrSOD1 protein encoded by the gene has typical highly conserved features of CuZnSODs, including two signature motifs and seven Cu/Zn-interacting residues. Transcription of PrSOD1 was highest in the larval fat body and at the fifth-instar larval stage. Recombinant PrSOD1 protein expressed in Escherichia coli displayed antioxidant activity and high thermal and pH stability, confirming that PrSOD1 encodes a functional enzyme. Exposure to three sublethal doses of chlorantraniliprole for 6, 12 or 24 h resulted in significantly increased malondialdehyde concentration in P. rapae larvae, indicating insecticide-induced oxidative stress. Furthermore, both PrSOD1 transcription levels and CuZnSOD activity were quickly (6 and 12 h, respectively) upregulated in larvae subjected to chlorantraniliprole, strongly suggesting that PrSOD1 plays an important role in protecting against oxidative damage and possibly chlorantraniliprole tolerance in P. rapae.

Ecotoxicity of neonicotinoids and diamides on population growth performance of Zygogramma bicolorata (Coleoptera: Chrysomelidae)

Relative ecotoxicity of approved neonicotinoids (i.e. imidacloprid, clothianidin, acetamiprid, thiacloprid, thiamethoxam and dinotefuran) and diamides (i.e. chlorantraniliprole, cyantraniliprole and flubendiamide) was examined on population growth parameters of Zygogramma bicolorata Pallister on parthenium under laboratory conditions at 27 ± 1 °C, 65 ± 5% relative humidity and 10 L : 14D photoperiod. The dose of all tested insecticides in the bioassay procedure was within a minimum range of their recommended field rate. In acute toxicity trial, imidacloprid caused highest rate of mortality in treated adults of Z. bicolorata, however, it was lowest in flubendiamide treatment followed by cyantraniliprole and chlorantraniliprole. Further, based on toxicity coefficient (E) value in acute toxicity trial, all were classified as harmful (H) and diamides were classified as moderately harmful (MH) as per IOBC classification. Moreover, chronic toxicity trials were carried out through life table response experiments (LTREs) in the F₁ progeny of acute toxicity experienced group. Prolonged development with the highest mortality was evident in as compared to diamides. Furthermore, population growth parameters i.e. potential fecundity (Pf), natality rate (m_x), intrinsic rate of increase (r_m), net reproductive rate (R₀) and finite rate of increase (λ) was greatly reduced in Z. bicolorata treated with neonicotinoids as compared with diamides. However, mean generation time (T_c), corrected generation time (τ) and the doubling time (DT) was prolonged in neonicotinoids followed by diamides. Furthermore, proportion of females was greatly reduced (0.43-0.48 females) in neonicotinoids as comparison to diamides (0.53-0.55 females) and control (0.67 females). On the basis of ecotoxicity trials, the tested neonicotinoids were highly toxic to Z. bicolorata than diamides. Therefore, diamide insecticides could be used with Z. bicolorata, however, for validation experimentation need to be done under natural field conditions.