Myzus Persicae Research Articles

Repellent Effects of Coconut Fatty Acid Methyl Esters and Their Blends with Bioactive Volatiles on Winged Myzus persicae (Sulzer) Aphids (Hemiptera: Aphididae).

Myzus persicae (Sulzer) (Hemiptera: Aphididae) is one of the most important aphid crop pests, due to its direct damage and its ability to transmit viral diseases in crops. The objective is to test whether spraying nanoemulsions of botanical products repels winged individuals of M. persicae in a bioassay in culture chambers. The bioactive volatiles were applied on pepper plants at a dose of 0.2% alone or at 0.1% of each component in blends. A treated plant and a control plant were placed at each side of an entomological cage inside a growth chamber. The winged individuals were released between the plants, in a black-painted Petri dish suspended by wires in the upper half of the cage. The most repellent products were farnesol (repellency index, RI = 40.24%), (E)-anethole (RI = 30.85%) and coconut fatty acid methyl ester (coconut FAME) (RI = 28.93%), alone or in the following blends: farnesol + (E)-anethole + distilled lemon oil (RI = 36.55%) or (E)-anethole + distilled lemon oil + coconut FAME (RI = 30.63%). The observed effect of coconut FAME on aphids is the first report of this product having a repellent effect on a crop pest. Repellent substances for viral disease vectors should be further investigated to develop new strategies for plant protection.

Compatibility of Chrysoperla carnea (Neuroptera: Chrysopidae) with nanoformulations of natural active substances.

Nanoformulations of essential oils (EOs) improve stability of the active ingredient, and thereby its biological activity and persistence. Because compatibility of EOs with natural enemies is not explored sufficiently, we evaluated the impact of nanoformulations of EOs (aniseed, lemon) or pure products (farnesol) on different activities of the generalist predator Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae). In dual choice bioassay, chrysopid larvae were significantly attracted to aniseed-treated pepper disks and deterred by farnesol. Larval activities (resting, walking, and preying) on treated leaves infested with Myzus persicae (Sulzer) (Hemiptera: Aphididae) were compared. There were no differences among nanoemulsions, nor aphid consumption varied. We studied the toxicity of nanoformulations to larvae and evaluated their development after contact with treated leaf disks, ingestion of treated artificial diet, and both routes of exposure (application of biopesticides on aphid-infested plants). This is the first evidence of the compatibility of EO nanoformulations with C. carnea by single route of exposure. Whether any effect appeared, it was sublethal. Compounds significantly reduced aphid consumption after 6 h on double route exposure, but this negative short-term effect disappeared as time progressed. Our results showed the optimal biopesticide to apply depends on which biological feature of the natural enemy we targeted. The key element to introduce these nanoemulsions is to match their persistence period on the crop with the release of the appropriate biological stage of C. carnea. This reinforces the fact that the main activities of C. carnea can be substantially maintained in joint application with nanoemulsions of EOs.

Insecticide-free reduction of Myzus persicae aphids on sweet pepper (Capsicum annuum L.) through MgSO4-faciliated amino acid and sugar reallocation

Fruits of sweet pepper (Capsicum annuum L.) are among the most consumed fresh fruits, however, their production can be affected by aphids, which feed on the amino acids in the leaves. Mg2+ in leaves plays a crucial role in the reallocation of amino acids from source organs (leaves) to sink organs (fruits). We hypothesize that foliar application of Mg2+ can reduce free amino acid concentration in leaves by promoting their transfer to sink fruits, thereby compromising aphid colonization by reducing their nutritional basis. To test this, a two-factorial experiment was conducted with sweet pepper subjected to aphid infestation with and without leaf MgSO4 application. The concentration of amino acids, sugars, organic acids and mineral nutrients was analysed in the leaves, leaf phloem sap and fruits. Mg2+application decreased the concentrations of amino acids and sugars that are key for aphid nutrition in both the leaf and phloem sap and increased the size and number fruits, indicating an increased sink strength in response to Mg2+. This response was accompanied by a reduced number of aphids on the entire plant. In results, the sugar and amino acid concentration in the phloem got less attractive for the aphids. We conclude that Mg2+ worsens the nutritional situation for aphids by facilitating the reallocation of metabolites to form fruits.

Transgenic cotton expressing Allium sativum leaf agglutinin exhibits resistance to whiteflies and aphids without negative effects on ladybugs

Cotton (Gossypium hirsutum L.) is of great economic importance as a cultivated crop in many parts of the world. In addition to being a pillar of the textile industry, cotton and its byproducts are used for livestock feed, seed oil, and other products. Bacillus thuringiensis crystal toxin (Bt) expression in cotton provides effective protection against chewing insects but does not defend plants from piercing/sucking insect pests. With the aim to create transgenic plants with resistance against piercing/sucking pests, we used Agrobacterium-mediated genetic transformation of cotton cultivar Coker 312 to express the Allium sativum leaf agglutinin (ASLA) gene from the phloem-specific rolC promoter. The ASLA transgene was stably inherited and showed Mendelian segregation in the T1 generation. Transgenic lines, expressing the ASLA gene, showed explicit resistance against major sap-sucking pests. Green peach aphid (Myzus persicae Sulzer) choice assays showed that 75% of aphids preferred untransformed cotton plants relative to those expressing the ASLA gene. In detached leaf bioassays, plants expressing ASLA caused 82% aphid mortality and 44–53% reduction in fecundity. Clip cage bioassays with whiteflies (Bemisia tabaci Gennadius) showed 74–82% mortality and 44–60% decrease in fecundity due to ASLA gene expression. In whole plant bioassays, whiteflies showed 77% mortality and a 54% decrease in fecundity on ASLA transgenics. Importantly, we did not observe a negative effect of the ASLA gene on ladybugs (Coccinella septempunctata) that consumed these whiteflies. Together, our findings demonstrate the potential of ASLA-transgenic cotton for providing protection against two devastating insect pests, whiteflies and aphids. The ASLA-transgenic cotton appears promising for direct commercial cultivation besides serving as a potential genetic resource in recombination breeding.

Effect of pollen consumption on development and intraguild predation of two predatory Coccinellidae

Many omnivorous predaceous coccinellids consume both pests like aphids and a range of plant-derived foods including pollen. It is critical to understand how plant-derived food like pollen could affect the fitness and interspecific interactions of predaceous coccinellids. This study investigated the effect of pollen consumption on the development, reproduction and intraguild predation (IGP) of two naturally co-existing aphidophagous ladybirds, Harmonia axyridis and Propylea japonica. Both species were provided with three diets including a moist canola pollen, the aphid Myzus persicae, or moist canola pollen together with aphids. The 1st instar larval of both H. axyridis and P. japonica could not survive and develop to the next larval stage when supplied with water alone. When fed on pollen only, 53 % of the H. axyridis larvae and 25 % of the P. japonica larvae successfully developed to adult. Both species exhibited an elongated development time, shorter larval body length and lower adult body weight than when offered with aphids and the mixed diet. In addition, P. japonica could not reproduce when fed on pollen alone. Interestingly, when pollen was provided as additional food, the overall IGP between larvae of H. axyridis and P. japonica was significantly reduced compared with water control or aphid as food alone. The results of this study indicated that pollen not only supports the survival of H. axyridis and P. japonica when prey is scarce, but also could benefit the co-existence of these species. For future study, it is necessary to investigate how pollinivory could benefit the fitness and biological control potential of H. axyridis and P. japonica under field conditions.

Overexpression of Two Odorant Binding Proteins Confers Chlorpyrifos Resistance in the Green Peach Aphid Myzus persicae.

The green peach aphid, Myzus persicae, is a worldwide agricultural pest. Chlorpyrifos has been widely used to control M. persicae for decades, thus leading to a high resistance to chlorpyrifos. Recent studies have found that insect odorant binding proteins (OBPs) play essential roles in insecticide resistance. However, the potential resistance mechanism underlying the cross-link between aphid OBPs and chlorpyrifos remains unclear. In this study, two OBPs (MperOBP3 and MperOBP7) were found overexpressed in M. persicae chlorpyrifos-resistant strains (CRR) compared to chlorpyrifos-sensitive strains (CSS); furthermore, chlorpyrifos can significantly induce the expression of both OBPs. An in vitro binding assay indicated that both OBPs strongly bind with chlorpyrifos; an in vivo RNAi and toxicity bioassay confirmed silencing either of the two OBPs can increase the susceptibility of aphids to chlorpyrifos, suggesting that overexpression of MperOBP3 and MperOBP7 contributes to the development of resistance of M. persicae to chlorpyrifos. Our findings provide novel insights into insect OBPs-mediated resistance mechanisms.

Possibility of Combined Use of Thymol and Carvacrol to Control the Number of Peach Aphids Myzus persicae (Sulzer, 1776)

The wide range of biological activity of essential oils in relation to pests gives reason to consider them as additional plant protection products and in other measures aimed at reducing the number of harmful arthropods. This paper presents the results of a study of the biological activity of a mixture of thymol and carvacrol, which are part of the essential oils of many plants, including oregano Origanum vulgare L. for the peach aphid Myzus persicae. The use of essential oil and a mixture of its components as fumigants has demonstrated their high aphidocidal potential. When processing the leaves of a forage plant (beans), the ability of a mixture of thymol and carvacrol to reduce the viability of female aphids and the number of offspring was established, and on vegetative plants (pepper) to negatively affect the survival of individuals of the daughter generation in the preimaginal period. The short duration of action allows the use of oils and individual components in conjunction with biological control agents and pollinators, and assumes a slight or complete absence of residues in food products. Preparations based on essential oils of plants can be used immediately before harvesting, due to the minimum waiting period.

Design the fusion double-strand RNAs to control two global sap-sucking pests

RNA interference (RNAi) is an effective pest management strategy through silencing the crucial genes in target organisms. However, the effectiveness of targeting a single gene is often limited by the silencing efficiency due to tissue or developmental stage-specific gene expression. Moreover, multiple pests often infest the same crop simultaneously under current ecological conditions. Therefore, a combined strategy of “targeting multiple genes” and “controlling multiple pests” is expected to yield better management results. In this study, homologous genes from two globally sap-sucking pests, the peach aphid (Myzus persicae) and the whitefly (Bemisia tabaci), were screened on a genome-wide scale. Subsequently, RNAi bioassays showed silencing the genes (MpAbd-A, MpH3, MpRpL27a, and MpScr) exhibited high mortalities in both species, which were further selected for designing fusion dsRNAs. These fusion dsRNAs resulted in higher mortalities in both pests than single gene silencing and posed a minimal off-target risk to the predator ladybeetle (Propylaea japonica) based on the sequence analysis. Finally, the tobacco plants expressing the fusion dsRNAs through virus-induced gene silencing (VIGS) technology enhanced the resistance to both pests. In conclusion, this study proposes a novel RNAi-based approach for managing two sap-sucking pests simultaneously.

High-temperature responses of Myzus persicae and its parasitoid Aphidius gifuensis in relation to heat level, duration and developmental stage.

Understanding how parasitoids respond to temperature is crucial for improving biological control strategies under the context of global warming. This study examined the suitability of Myzus persicae and its parasitoid Aphidius gifuensis to varying temperature conditions, as well as the stage-specific response of A. gifuensis to high temperatures. High temperatures had a significant impact on the both M. persicae and A. gifuensis. When exposed to 36°C, M. persicae developed more slowly and produced smaller adults compared to control, regardless of the duration of exposure (2, 4 or 6 h); additionally, the survival rate of M. persicae nymphs sharply decreased under these conditions. Exposure to 36°C for 4 h negatively impacted the development of A. gifuensis. Female parasitoids exposed to 32°C developed into smaller adults, whereas males exposed to all three temperature levels were smaller compared to control group. Female parasitoids exposed to high temperatures, regardless of the specific heat level and duration, exhibited reduced longevity and decreased fecundity. None of the parasitoids exposed to 36°C for 6 h daily developed into adults. Heat treated during early developmental stages (2 and 4 days old) had a greater influence on parasitoid development, whereas heat treatment at 4 and 6 days old had a more significant impact on its fecundity. High temperatures not only directly affected the performance of A. gifuensis, but also exerted indirect effects by influencing the quality of the host aphids M. persicae. The deleterious effects of high temperature on larvae can persist into the adult stage, affecting the longevity and reproduction of adults. These findings are important for the utilization of A. gifuensis in the control of M. persicae in warming environments. © 2024 Society of Chemical Industry.

Synergistic Insecticidal Interaction of <i>Aegle marmelos</i> and <i>Mentha piperita</i> against <i>Myzus persicae</i>

The efficacy of natural pesticides derived from Aegle marmelos and Mentha piperita leaves was investigated against green peach aphids (Myzus persicae). The extracts obtained via boiling and soxhlet methods from A. marmelos and M. piperita leaves were combined and tested for synergistic effects. The results indicate a 100% efficacy rate at a concentration of 500 ppm (A. marmelos) + 400 ppm (M. piperita), highlighting the potential of these botanical extracts as ecofriendly alternatives.

Analysis of Twenty Years of Suction Trap Data on the Flight Activity of Myzus persicae and Brevicoryne brassicae, Two Main Vectors of Oilseed Rape Infection Viruses

Myzus persicae and Brevicoryne brassicae are the main aphid pests and vectors of viruses that attack many crops, including oilseed rape, the most commonly grown dicotyledonous crop in the Czech Republic. In this study, we analysed the flight activity of both aphids from five suction traps over 20 years (2004–2023). We focussed on (i) the influence of the ban on seed dressing with neonicotinoids on aphid catches, (ii) the influence of the average temperature on flight activity, and (iii) the number of males/females caught in the suction traps. We compared the data on aphid flight activity at the coldest and warmest sites and found that migration starts about 10 days earlier at the warmest site than at the coldest site and that aphid populations are more numerous here. The number of catches in suction traps was observed for both aphids after the ban on neonicotinoids was significantly increased. For M. persicae, it was about 9 times higher, while for B. brassicae, it was about 1.3 times higher. In addition, we observed a significant decrease in the number of males in M. persicae with a simultaneous increase in the number of females (in autumn), which could be an indication of the formation of anholocyclic populations. Overall, our results showed a significantly high abundance of both aphid species depending on the observed locations, which seems to be related to the ban of neonicotinoids. Therefore, an effective alternative is needed to improve the control of aphid vectors that can ensure the stability of crops against aphid-transmitted virus diseases.

Safety evaluation and sublethal effect of broflanilide on Aphidius gifuensis.

Ensuring the safety of insecticides to natural enemy insects of pests is crucial for integrating chemical and biological control strategies. Broflanilide, a novel meta-diamide insecticide, exhibits high insecticidal activity against Myzus persicae (Sulzer) (Hemiptera: Aphididae). To integrate chemical and biological control against M. persicae, we assessed the toxicity of broflanilide to Aphidius gifuensis, and evaluated its safety and sublethal effects. The LC10, LC25, and LC50 values of broflanilide against A. gifuensis were 0.733 mg/L, 1.613 mg/L, and 3.852 mg/L, respectively. The selectivity toxicity ratio of broflanilide to A. gifuensis was 1.516, indicating higher toxicity to M. persicae compared to A. gifuensis. The risk quotient of broflanilide to A. gifuensis adults was 6.18. The percent reduction in the emergence of the parasitoid pupae was -1.15, with a risk grade of 1. The sublethal concentration of broflanilide had no significant influence on the intrinsic rate of increase (r), finite rate of increase (λ), net reproductive rate (R0), and mean fecundity (F) of A. gifuensis in the F1 generation. The mean generation time (T) increased by 0.51 days and 0.39 days in the LC10 and LC25 treatments, respectively; the difference between LC10 treatment and the control was significant, while the difference between LC25 treatment and the control was not significant. The results showed that the sublethal concentration of broflanilide did not have a significant inhibitory effect on the population growth of A. gifuensis.

Combined transcriptome and metabolome analysis identifies triterpenoid-induced defense responses in Myzus persicae Sülzer-infested peach.

The defense response of peach (Prunus persica) to insect attack involves changes in gene expression and metabolites. Piercing/sucking insects such as green peach aphid cause direct damage by obtaining phloem nutrients and indirect damage by spreading plant viruses. To investigate the response of peach trees to aphids, the leaf transcriptome and metabolome of two genotypes with different sensitivities to green peach aphid (GPA, Myzus persicae) were studied. The transcriptome analysis of infected peach leaves showed two different response patterns. The gene expression of aphid-susceptible peach plants infected by aphids was more similar to that of the control plants, while the gene expression of aphid-resistant peach plants infected by aphids showed strongly induced changes in gene expression compared with the response in the control plants. Furthermore, gene transcripts in defense-related pathways, including plant-pathogen interaction, MAPK signaling, and several metabolic pathways, were more strongly enriched upon aphid infestation. Untargeted secondary metabolite profiling confirmed that aphid treatment induced larger changes in aphid-resistant peaches than in aphid-susceptible peaches. Consistent with transcriptomic alterations, nine triterpenoids showed extremely significant GPA-induced accumulation in aphid-resistant peaches, whereas triterpenoid abundance remained predominantly unchanged or undetected in aphid- susceptible peaches. Furthermore, some types of transcription factors (including WRKYs, ERFs, NACs, etc.) were more strongly induced upon GPA infestation in aphid-resistant peaches but not in aphid-susceptible peaches. Aphid feeding-dependent transcriptome and metabolite profiles provide the foundation for understanding the molecular mechanisms underlying the response of peach to aphid infestation. These results suggested that accumulation of specialized triterpenoids and the corresponding pathway transcripts may play a key role in peach GPA resistance.

Unraveling jasmonate-mediated plant immunity against green peach aphid (Myzus persicae) in peach: an integrated transcriptomic and RNA sequencing approach

Unraveling jasmonate-mediated plant immunity against green peach aphid (Myzus persicae) in peach: an integrated transcriptomic and RNA sequencing approach

Densovirus infection facilitates plant-virus transmission by an aphid.

The interactions among plant viruses, insect vectors, and host plants have been well studied; however, the roles of insect viruses in this system have largely been neglected. We investigated the effects of MpnDV infection on aphid and PVY transmission using bioassays, RNA interference (RNAi), and GC-MS methods and green peach aphid (Myzus persicae (Sulzer)), potato virus Y (PVY), and densovirus (Myzus persicae nicotianae densovirus, MpnDV) as model systems. MpnDV increased the activities of its host, promoting population dispersal and leading to significant proliferation in tobacco plants by significantly enhancing the titer of the sesquiterpene (E)-β-farnesene (EβF) via up-regulation of expression levels of the MpFPPS1 gene. The proliferation and dispersal of MpnDV-positive individuals were faster than that of MpnDV-negative individuals in PVY-infected tobacco plants, which promoted the transmission of PVY. These results combined showed that an insect virus may facilitate the transmission of a plant virus by enhancing the locomotor activity and population proliferation of insect vectors. These findings provide novel opportunities for controlling insect vectors and plant viruses, which can be used in the development of novel management strategies.

Impact of Inoculative Releases of Trichogramma chilonis for Helicoverpa armigera and Hippodamia variegata for Myzus persicae in Ecologically Engineered Tomato Ecosystem of Kashmir

Impact of Inoculative Releases of Trichogramma chilonis for Helicoverpa armigera and Hippodamia variegata for Myzus persicae in Ecologically Engineered Tomato Ecosystem of Kashmir

Volatile cis-jasmone affects the tri-trophic interactions among the potato plants, the green peach aphid (Myzus persicae), and the parasitoid (Aphidius gifuensis)

New strategies for protecting crops from aphid attacks must be developed. The present study aimed to examine the effect of cis-Jasmone (CJ), an activator of plant defense, on potato plants. Plants were sprayed with an exogenous application of CJ at 12, 24, and 48 h; and the green peach aphid, Myzus persicae Sulzer, and its parasitoid, Aphidius gifuensis, were used to evaluate the tri-trophic interactions of the aphids, parasitoids, and plants. In this work, we examined that the adult M. persicae produced fewer nymphs on CJ-treated plants at 12, 24, and 48 h than on control plants. Furthermore, M. persicae nymphs that fed on CJ-treated plants at 48 h had a lower mean relative growth rate (MRGR). Moreover, the intrinsic rate of population increase (r) was significantly lowered in CJ-treated plants at 12, 24, and 48 h. CJ-treated plants at all time durations showed considerably less settlement of aphid than control plants. In the olfactometer bioassay, the parasitoid exhibited a prolonged duration in the arm treated with volatiles from CJ-treated plants at 12, 24, and 48 h in comparison to the control. Moreover, the salicylic acid and jasmonic acid marker gene expression levels were significantly upregulated by CJ-treatment. Surprisingly, aphids raised on CJ-treated potato plants showed higher transcriptional levels of detoxifying enzymes. The findings of this research will provide new insights into the possible applications of important volatile components like cis-jasmone in integrated pest management systems, in addition to enhancing our comprehension of the ways in which plant volatiles affect the crop community.

Potential of entomopathogenic fungi to control insect pests and disease at lettuce and arugula crops

The lettuce (Lactuca sativa L.) (Asteraceae) and arugula (Eruca sativa Miller) (Brassicaceae) crops are attacked by various pests and diseases, but the control is usually done with agrochemicals. We evaluate the control of pests and diseases by systematic applications of the entomopathogenic fungi strains Metarhizium anisopliae IBCB425 and Beauveria bassiana IBCB66 both 300g c.p. in the planting groove and 200 g c.p. ha-1 on the foliage, in weekly applications at lettuce and arugula crops planted in association. For the evaluation of pests and diseases, 15 plants were evaluated at random in three beds per treatment. In the lettuce crop occurred the presence of aphids (Myzus persicae Hemiptera:Aphididae), whiteflies (Bemisia tabaci Hemiptera: Aleyrodidae), thrips (Frankliniella schultzei Thysanoptera:Thripidae), leafhoppers Agallia albidula (Hemiptera: Cicadellidae) and septoria disease (Septoria lactucae). In the arugula crop the same pests occurred, but with any disease. The fungi B. bassiana and M. anisopliae controlled F. schultzei and S. lactucae at lettuce crop, B. tabaci in both crops, but did not control M. persicae and A. albidula in both crops. The fungus B. bassiana decreased the mean number of leaves per plant and the mean of dry mass weight of arugula plants in relation to the control treatment, but the sample size may have interfered with these results. The two fungi could be used as biological control agents of pests and diseases at lettuce and arugula crops, especially in organic farming.

Synergism of (E)-β-farnesene and Its Analogue to Insecticides against the Green Peach Aphid Myzus persicae.

With high aphid-repellent activity but low stability, (E)-β-farnesene (EβF), the major component of the aphid alarm pheromone, can be used as a synergist to insecticides. Some EβF analogues possess both good aphid-repellent activity and stability, but the synergistic effect and related mechanism are still unclear. Therefore, this study investigated the synergistic effect and underlying mechanism of the EβF and its analogue against the aphid Myzus persicae. The results indicated that EβF and the analogue showed significantly synergistic effects to different insecticides, with synergism ratios from 1.524 to 3.446. Mechanistic studies revealed that EβF and the analogue exhibited effective repellent activity, significantly upregulated target OBP genes by 161 to 731%, increased aphid mobility, and thereby enhanced contact with insecticides. This research suggests that the EβF analogue represents a novel synergist for insecticides, with the potential for further application in aphid control owing to its enhanced bioactivity and the possibility of reducing insecticide doses.

Eco-friendly and sustainable approaches against aphids management (Myzus persicae) and dissipation studies of imidacloprid in important cash crop capsicum under protected and open condition

Capsicum is generally infested with many biotic agents mainly sucking insects, among them the major is aphid (Myzus persicae). Chemical management is one of the most common strategies for their management. However, there are no recommended insecticides for insect management in polyhouse. An experiment was designed to assess the bio-potency of four popularly used insecticides (Imidacloprid-17.8SL, Acephate-75SP, Dimethoate-30EC and Buprofezin-25SC), a botanical (Neem oil 10000 ppm) and two entomopathogenic fungi (Metarhizium anisopliae 1.15%WP and Lecanicillium lecanii 1.15%WP) for two consecutive seasons. Most effective and the highest reduction of aphid population (78.14–81.92 %) were found in imidacloprid (17.8SL) treated plots. This effective molecule imidacloprid was further studied for its dissipation pattern under polyhouse and open condition and found that the imidacloprid residues in capsicum fruit dissipated below quantification limit (BQL) within 10days after final spray and the residues in the soil sampled at harvest time were found below the detection level. The half-lives of imidacloprid were 1.88 and 2.61 days under polyhouse and 1.07 and 1.52 days in open field at recommended doses (25 g a.i. ha−1) and double doses (50 g a.i. ha−1) of application respectively. The dietary exposure of imidacloprid on capsicum fruit under both conditions exposed that hazard quotient (HQ) values obtained from the different treatment doses have not exceeded the upper limit of toxicity (HQ < 1) and imidacloprid residues in the fruits were found below the existing MRL (Maximum Residue Limit) values (0.5 mg/kg) at 3 days after its final applications. Thus, imidacloprid may be considered as the effective chemical management option against aphids in capsicum under polyhouse and open field having no harmful effect on human consumption.