Insect Pests Research Articles

Evaluating the Efficacy of Insecticide on the Management of Onion Thrips (Thrips tabaci, Lindemann) in Northwestern Zone of Tigray

Ethiopia has enormous potential to produce the onions throughout the year both for domestic use and export market. It is also the most cultivated and high market value of vegetable crops in Tigray Northern Ethiopia. However, the productivity of onion is highly constrained such as insect pests, diseases, lack of improved verities, lack of improved management practices etc. The major insect pest of onion is Onion thrips and important pests especially in areas where onions are grown under irrigation. The purpose of this study was to test the insecticide chemicals application and application frequency on the Onion production technologies. Therefore, field experiment was conducted to evaluate the insecticide chemical applications with frequency application in 2017 and 2018 under irrigation conditions. Thirteen treatments were used three different insecticide types namely Karatae 5% EC, Dimethote 40%EC, Profit72%EC with four different spraying frequency and untreated (control) laid out in Randomized Complete Block Design (RCBD) with three replications. The current findings showed that the profitable yield was obtained Karatae 5% EC (1st spray) (14.25 t ha-1) followed by Profit72%EC (4th spray) that is (20.25 t ha-1) and the obtained profit was 128053 &181788 birr per ha with the maximum Marginal Rate of Return of 3025 & 2417% respectively in Tselemti woreda. In Medebaayzana woreda also, the profitable yield was obtained Karatae 5% EC (1st spray) (25.79 t ha-1) followed by Karatae 5% EC (4st spray) at (27.75 t ha-1) & Dimethote 40% EC (3rd spray) at (25.78 t ha-1) and 231976, 249463 & 231544 birr per ha obtained profit with the maximum Marginal Rate of Return of 2634, 2395 & 2311 % respectively. Therefore, Karatae 5% EC (1st spray) in Tselemti & Medebayzana woreda & Profit72%EC (4th spray) in Tselemti woreda and Dimethote 40% EC (3rd spray) in Medebayzana woreda was profitable preventive Onion Thrips for Onion production in the studies area.

Lepidoptera larvae (Insecta) responsible for herbivory on Vanilla spp. (Orchidaceae) in the Federal District, Brazil

Given its culinary importance and high market value, the cultivation of Vanilla (Orchidaceae) has been expanding annually in Brazil. As observed in many crops, the increase in cultivated areas leads to a greater incidence of insects associated with species of this genus. This study reports the herbivory of larvae from Cremna thasus (Stoll, 1780) (Papilionoidea: Riodinidae: Riodininae), Hypercompe cunigunda (Stoll, 1781) (Noctuoidea: Erebidae: Arctiinae), and Spodoptera cosmioides Walker, 1858 (Noctuoidea: Noctuidae: Noctuinae) on Vanilla bahiana Hoehne and V. planifolia Andrews in the Federal District, Brazil. A list of 19 Lepidoptera species from six families associated with Vanilla spp. worldwide is provided based on a literature review. Most (n=15) of them exhibit polyphagous larvae. Given reports of exotic larvae spreading with orchids worldwide and the discussed larval polyphagy, we address precautions that producers of Vanilla and other orchids should take to reduce the incidence of insect pests in crops, especially in areas with intensive cropping systems involving annual commodities such as maize and soybean.

Whitefly‐Pathogenic Beauveria bassiana JEF‐507 as a Competitive Biopesticide, Chongchae‐Stop

ABSTRACTSilverleaf whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae), is a destructive insect pest damaging to diverse crops by vectoring several plant pathogenic viruses, which consequently causes economic losses in crop production. As the resistance of whiteflies to chemical insecticides is increasing, this study aimed to investigate the potential of entomopathogenic fungi as an alternative. A total of 72 entomopathogenic fungal isolates, collected from soils using Tenebrio molitor larvae as an insect baiting method, were assessed for their virulence against 2nd nymphs of whitefly. Their virulence was assayed by dipping whitefly‐infested tomato leaves in fungal conidia suspensions at 1.0 × 107 conidia/mL. Among the tested isolates, two isolates of Beauveria bassiana JEF‐462 and JEF‐507 showed high virulence. In the assessment of virulence depending on conidia concentrations, the estimated LC50 values for JEF‐462 and JEF‐507 were similarly 8.7–14.0 × 107 conidia/mL. However, B. bassiana JEF‐507 showed higher conidial productivity and thermotolerance on most of tested 12 grain substrates than B. bassiana JEF‐462, and millet was the most suitable grain substrate. Additionally, siloxane as a surfactant was able to sufficiently exhibit the insecticidal activity of JEF‐507 against whitefly nymphs compared with other surfactants. In a pot‐based greenhouse trial, JEF‐507 showed higher control efficacy than chemical insecticides, dinotefuran and spinetoram. This work suggests that B. bassiana JEF‐507 could be competitively used as a biopesticide to control silverleaf whiteflies while overcoming current resistance issues. The JEF‐507 isolate has been registered in Korea, 2022 and successfully commercialised as the name of Chongchae‐Stop in this local market to control whitefly and thrips.

Biology of the potter wasp Delta esuriens (Fabricius, 1787) (Hymenoptera: Vespidae: Eumeninae) with details on its nesting and mating behaviours, development, and ecology

The biology of the potter wasp Delta esuriens (Fabricius) is studied in Vietnam. The eumenine built its mud nests in numerous sites, usually in shaded locations. The nest consisted of 1–8 pot-shaped cells and was sometimes covered with a lay of mud after it was provisioned completely. The egg was laid before provisioning. The female stored 3–10 caterpillars of Noctuidae, Geometridae, Pieridae, and Plutellidae per nest cell, and left nest cells open during egg-laying and provisioning. The developmental time from the egg to the emergence of the adult wasp was 20–30 days under laboratory conditions. Mating of D. esuriens was taken place at flowers of Bidens pilosa L. and Celosia cristata L., usually in the morning. The male seized a female, grasped her pronotum with his forelegs and quickly copulated with her for 4–10 s. Delta esuriens overwintered as prepupae and occurred in the wild for about eight months a year. The sex ratio was 1.17. The developmental mortality ratio was 25 % under laboratory conditions and 54.4 % under natural conditions. Chrysis dissimilis Dahlbom, Chrysis sp., Trichrysis lusca (Fabricius), Melittobia sosui Dahms, two Sarcophagidae satellite flies, and small red ants were predators of the eumenine. This study provides a better understanding of the biology and ecology of D. esuriens, can be used to aid in studies of phylogeny and evolution of the nesting behaviour in Delta, and can help in developing measures to exploit this potter wasp in the biocontrol of insect pests in vegetable crops.

α-Solanine and α-Tomatine Affect the Retrocerebral Complexes of Tenebrio molitor and Zophobas atratus Beetles.

Presently, the European Commission is moving forward with a plan to reduce the use of chemical pesticides and increase the percentage of organic farming by 2030; this plan demands increased availability of biopesticides for organic farming. Glycoalkaloids are a class of molecules found in certain plants, including tomatoes and potatoes, which contain sugar and an alkaloid group. These compounds are known to have insecticidal properties, as they can act as natural defenses against insect pests. This study examined how a biological substance, glycoalkaloids, affects mortality and the retrocerebral complex of two beetle species, Tenebrio molitor and Zophobas atratus. More specifically, we focused on two glycoalkaloids, α-solanine and α-tomatine. Although these two insects belong to the same taxonomic family, they were not equally susceptible to these substances. In the mortality test, we observed that the T. molitor beetle seemed more susceptible, whereas the changes in the retrocerebral complex were more significant in the case of Z. atratus. In general, the effects vary between substances and insects, and changes in the retrocerebral complex may impair the reproduction of insects.

Exposure to organophosphate insecticides induces behavioral changes and acetylcholinesterase inhibition in Apis mellifera

European honey bee (Apis mellifera L.) is an essential pollinator that contributes significantly to the global ecosystem and agricultural productivity. However, their population has been facing unprecedented threats, primarily due to their exposure to various pesticides, including organophosphates. These pesticides are being widely used in agriculture to control insect pests due to their efficacy, but their non-selective nature raises concerns about their impact on honey bees. Insecticides viz., chlorpyriphos 20 Emulsifiable Concentrate, dimethoate 30 Emulsifiable Concentrate, and profenophos 50 Emulsifiable Concentrate at a range of 0.005–0.09 per cent concentration were evaluated through two modes of application viz., topical and oral. Acetylcholinesterase (AChE) activity was measured at various intervals (1 and 24 hours) to assess enzyme inhibition. Behavioral observations and statistical analyses, including factor analysis with Eigen values, were employed to evaluate the impact of exposure on bee behavior and physiological responses.The results revealed two factors with Eigen value > 0.95 in both topical as well as oral method which accounted for 88.28 and 88.80 per cent of the variation in behaviour, respectively. Insecticides applied to honey bee A. mellifera in both topical as well as oral methods resulted in significant inhibition of the Acetyl choline esterase enzyme (AChE) activity. Studies revealed higher AChE inhibition (%) in oral method as compared to topical method. AChE inhibition percentage increased from 25.15 (1 Hour after treatment) to 58.25 (24 Hours after treatment) with lower concentration (0.005) of chlorpyriphos in topical method while as it reached from 27.66 to 60.94 with same concentration and same time in oral method of application. AChE inhibition percentage increased from 35.81 (1 Hour after treatment) to 78.30 (24 Hours after treatment) with higher concentration (0.06) of chlorpyriphos in topical method while as it reached from 40.35 to 80.18 with same concentration and same time in oral method. Similar trend was observed in dimethoate, and profenophos where AChE inhibition increased from 17.30, 27.15 (1 Hour after treatment) to 57.18, 61.81 (24 Hours after treatment), respectively in topical method and 20.67, 28.80 (1 Hour after treatment) to 59.85 64.04 (24 Hours after treatment), respectively in oral method. Similarly, with higher concentrations of dimethoate (0.07), and profenophos (0.09), per cent inhibition increased from 34.54, 38.60 (1 Hour after treatment) to 75.68, 79.62 (24 Hours after treatment), in topical method and 37.25, 41.23 (1 Hours after treatment) to 77.86, 82.73 (24 Hours after treatment), in oral method, respectively. Thorough risk assessments are vital for evaluating the effects of agrochemicals on Apis mellifera. The findings highlight the necessity for updated pesticide regulations and broadened conservation strategies that take into account the diverse ways pollinators are exposed to agrochemicals in the environment. The study assessed the impact of different insecticides on Apis mellifera by comparing topical and oral exposure methods. The study also aimed to analyze the behavioral effects of insecticide exposure on Apis mellifera, assessing variations in response and enzyme inhibition.The research focused on evaluating Acetylcholinesterase (AChE) inhibition to better understand the risks posed to honeybees in agricultural environments.

Effect of application of ozone at low-pressure on the technological properties, phenolic compounds, and antioxidant capacity of common beans during storage

The objective of this study was to assess the effects of low-pressure ozone treatment on the technological quality, phenolic compounds, and antioxidant capacity of common beans (Phaseolus vulgaris L.) during storage. Samples of 5.0 kg of dry beans were exposed to ozone in a hypobaric chamber with an internal volume of 70 L. Ozone was injected until the internal chamber pressure reached 100000 Pa, with an inlet concentration of 61.37 mg L−1 and flow rate of 1.0 L min−1. Ten cycles of ozone injection were adopted. Oxygen was used in control treatment. The effect of the treatments on the grain quality was assessed over storage for 180 days. Ozone did not affect the percentage composition of the dry beans, which exhibited 18.76% of protein, 11.66% of moisture content, 3.44% of minerals, 1.32% of lipids, and 64.51% of carbohydrates. A significant difference (p < 0.05) between the treatments and the control was noticed in total titratable acidity. The luminosity (L∗) and hue (h∗) of the grains were not altered by ozonation. Ozone had a significant effect (p < 0.05) on the phenolic content of the dry beans but no significant effect (p > 0.05) on their antioxidant capacity. The phenolic compounds content and antioxidant capacity decreased over storage in all treatments. Ozone application at low pressures proved a promising technology for controlling insect pests and promoting fungal decontamination without altering dry bean quality throughout storage.

Entomopathogenic nematode detection and counting model developed based on A-star algorithm

Entomopathogenic nematodes are soil-dwelling living organisms widely employed in the biological control of agricultural insect pests, serving as a significant alternative to pesticides. In laboratory procedures, the counting process remains the most common, labor-intensive, time-consuming, and approximate aspect of studies related to entomopathogenic nematodes. In this context, a novel method has been proposed for the detection and quantification of Steinernema feltiae isolate using computer vision on microscope images. The proposed method involves two primary algorithmic steps: framing and isolation. Compared to YOLO-V5m, YOLO-V7m, and YOLO-V8m, the A-star-based developed network demonstrates significantly improved detection accuracy compared to other networks. The novel method is particularly effective in facilitating the detection of overlapping nematodes. The developed algorithm excludes processes that increase space and time complexity, such as the weight document, which contains the learned parameters of the deep learning model, model integration, and prediction time, resulting in more efficient operation. The results indicate the feasibility of the proposed method for detecting and counting entomopathogenic nematodes.

Life table and feeding behavior of Myzus persicae (Hemiptera: Aphididae) at sublethal concentrations of Afidopyropen, Spirotetramat and sulfoxaflor

AbstractThe green peach aphid Myzus persicae Sülzer is a major insect pest of cruciferous plants, including vegetables such as Chinese cabbage. The objective of the present study was to determine the effects of sublethal afidopyropen and spirotetramat concentrations on the survival and reproduction of M. persicae. In addition, we used an electrical penetration graph (EPG) to study the feeding behavior of M. persicae on Chinese cabbage leaves treated with various concentrations of afidopyropen, spirotetramat and sulfoxaflor. The results showed that sublethal concentrations (LC10 and LC30) of afidopyropen and spirotetramat significantly decreased adult longevity and fecundity. However, sulfoxaflor had no significant effects. Several population parameters, including the net reproductive rate (R0), intrinsic rate of increase (rm), mean generation time (T), finite rate of increase (λ), and doubling time (DT), were significantly decreased only at the LC30 of spirotetramat. According to the EPG feeding behavior analyses, when all three insecticides were applied at LC30, the nonpenetration (NP) waveform significantly increased. The above results can be used as basic data for the well‐planned use of insecticides.

Endophyte mixture effects on ryegrass staggers in sheep

Epichloë endophytes protect ryegrass from insect pests, but no strain provides both the highest level of insect protection and lowest risk to livestock health. This study examined mixtures of endophytes to find combinations that could mitigate ryegrass staggers in sheep. At Barenbrug NZ, Courtenay, pastures varying widely in sown proportions of perennial ryegrass infected with nea3, nea12 and standard endophyte (SE) were sown in May 2019 and tested with lambs in summer and hoggets in spring 2020. In summer, sown proportions of &gt;65% nea3, &lt;35% nea12 and no SE delayed severe staggers (score 4–5) by 1 week. Alkaloid profiles of these pastures included the tremorgens epoxyjanthitrem I (&lt;0.28 ppm) of nea12 and paxilline (&lt;0.15 ppm) and terpendole C (&lt;1.37 ppm) of nea3. In spring, sown proportions of &gt;65% nea3 and &lt;35% nea12 and/or SE did not induce staggers (score 0–0.1). Those pastures had low concentrations of the potent tremorgen lolitrem B (&lt;0.30 ppm) of SE, epoxyjanthitrem I (&lt;0.39 ppm) of nea12 and paxilline (&lt;0.09 ppm) and terpendole C (&lt;0.41 ppm) of nea3 and SE. The optimal endophyte formulations that minimised staggers across summer and spring were &gt;65% nea3, &lt;35% nea12 and no SE.

Plant‐based protein crops and their improvement: Current status and future perspectives

AbstractThe plant‐based protein industry is rapidly growing and is projected to grow to over $27 billion by 2030. In addition to monetary benefits, plant‐based protein crops, particularly pulse crops (i.e., legume species with dry edible seed), can supplement the existing crop biodiversity and break the disease and insect pest cycle in drastically changing climatic conditions. Most commercially available plant‐based protein ingredients come from only 2% of the 150 plant species on which our food supply depends. Therefore, it is imperative to diversify the cropping system with pulse crops that provide a more nutritious, climate‐resilient, sustainable food value chain. At present, a large portion of US pulse crop production is exported, yet the shifting demographics, dietary preferences, and a rise in domestic consumption present enormous potential for existing and emerging pulse crops, as well as their breeding. Despite a rise in demand from consumers and industries, farmers are yet to fully reap the benefits of these crops due to a shortage of improved varieties. These new varieties could lead to a diverse, sustainable protein supply that satisfies the growing domestic and global demand for plant‐based foods. This review intends to comprehensively explore the geographical and cultural acceptance of plant‐based proteins, manufacturing techniques, protein products, anti‐nutritional factors, techniques and tools for protein estimation, high‐throughput estimation of seed protein, protein composition requirements in food, breeding strategies, crop improvement, and resources to improve plant‐based protein pulse crops.

Forest health under climate change: impact of insect pests

Forest health under climate change: impact of insect pests

African Horned Melon (Cucumis metuliferus): Climate‐Resilient Crop and Gene Donor in the Breeding of Major Cucurbits

ABSTRACTAfrican horned melon (Cucumis metuliferus E. Meyer ex Naudin, 2n = 2x = 24) is an under‐researched and under‐utilised cucurbit crop primarily grown for its nutritious fruit. In its centre of diversity, the crop is valued for its relatively high tolerance to insect pests, diseases, drought and heat stress. It is a potential opportunity crop and a valuable source of genes to major Cucumis species, including cucumber (Cucumis sativas L.) and melon (C. melo L.). Its climate resilience and nutrient‐rich fruit provide niche market opportunities. Hence, production and value‐adding will make African horned melon a crop of choice globally. There is a need for an in‐depth investigation into the genetic diversity, breeding and food composition of the crop. Therefore, the objective of this review was to provide perspectives on the production and breeding status of African horned melon to appraise its genetic value for human welfare, strategic production, genetic conservation and breeding of market‐preferred varieties, including closely related Cucumis species. The first section described the botany, production status, germplasm resources and characterisation based on phenotypic and genetic markers. This is followed by breeding progress for biotic and abiotic stress tolerance, utilities and challenges of gene transfer and potential rootstock to Cucumis species, especially cucumber and melon. The review summarised the main breeding goals and approaches, including mutation breeding to fast‐track the development of new varieties. Information presented in the review will guide cultivar design in African horned melon or related cucurbits, aiming for superior agronomic and nutritional quality traits and tolerance to biotic and abiotic stresses.

Molecular Diagnostics for Monitoring Insecticide Resistance in Lepidopteran Pests

Chemical control methods to prevent crop damage have long been directly implicated in the selection of lepidoptera insect populations resistant to insecticides. More recently, new products featuring different modes of action (MoA), developed to mitigate the negative effects of control management on both producers and the environment, are rapidly losing efficacy due to the emergence of insect resistance. Among these, certain resistances are associated with molecular changes in the genomes of pest insects that are valuable for developing molecular markers for diagnostic tools, particularly the point mutations. Molecular diagnosis represents an innovative solution for insecticide resistance management (IRM) practices, allowing for the effective monitoring of insecticide resistance. This approach facilitates decision making by enabling the timely alternation between different modes of action (MoAs). In this context, this review focuses on the major lepidopteran pests that affect globally significant crops, discussing the impacts of insecticide resistance. It gathers literature on diagnostic methods; provides a comparative overview of the advantages of different techniques in terms of efficiency, cost, precision, sensitivity, and applicability; and highlights several novel diagnostic tools. Additionally, this review explores the coffee leaf miner, Leucoptera coffeella, as an applied model to illustrate potential approaches for more effective and sustainable control strategies.

Study the phytochemical, Biological and pharmacological aspects of Azadirachta indica: A review

Neem (Azadirachta indica) is a fast-growing tropical evergreen plant that belongs to the Meliaceae family. Its compounds have been shown to be effective against illnesses and insect pests that are significant economic concerns. The plant's whole body has biopesticidal properties, especially in the form of extracts from the leaves, bark, and roots. Every part of the plant has been utilized medicinally and is now considered a treasure in contemporary medicine. Salannin, quercetin, nimbolinin, nimbin, nimbidin, nimbidol, and azadirachtin are among the beneficial active compounds that have been isolated from several plant sections. This review article's primary goal is to provide information on a range of pharmacological activities, including anti-inflammatory, anti-cancer, anti-bacterial, antiviral, antifungal, antihelmethic, antidiabetic, wound-healing, and ulcer-preventing properties. activity hepatoprotective, Effects on Immunomodulation and Antinephrotoxicity.

Insect biotremology—An introduction

AbstractBiotremology, officially coined in 2016, has rapidly emerged as a distinct scientific discipline, focusing on the study of substrate‐borne mechanical waves in animal communication, particularly among insects. Initially seen as a niche within bioacoustics, biotremology is now recognized for its broad significance, rivalling chemical communication in its prevalence. This special issue highlights the multidisciplinary nature of biotremology, with research spanning insect behaviour, ecology and pest management. Studies showcase advances in understanding vibrational communication across diverse insect taxa, the development of new tools for reliable playback experiments and the growing potential of biotremology in applied pest control. This collection provides a snapshot of a dynamic field in rapid expansion, pushing the boundaries of both fundamental research and practical applications.

Evaluation of IPM Module for the Management of Key Insect Pests in Chilli

Chilli is a crop cultivated in tropical and subtropical regions of India, and the crop is attacked by a multitude of pests at different crop stages. The present study revealed that field experiments were laid out with three treatments, viz., IPM module, farmer practice, and untreated control, at Kuttiyagoundanur village of Kolathur block of Salem District, Tamil Nadu. The results of the IPM capsule for the management practices of major pests and diseases, including viral diseases in chillies. The pre-treatment count on thrips/leaf was non-significant in all treatments, and it ranged from 7.20 to 8.40 thrips/leaf. Among the three treatments, farmers practice of chemical control recorded less infestation of 2.93 thrips/leaf, followed by the IPM module recording 3.60 thrips/leaf. Before adoption of treatment, the mite/leaf count was between 17.09 and 19.23 mite/leaf. The IPM module recorded less infestation of 5.32 mites/leaf, followed by farmers practice recording 12.90 mites/leaf. The pre-treatment count of Helicoverpa armigera larvae was between 3.20 and 3.72 larvae/plant. Among the treatments, chemical control recorded less infestation of fruit borer and fruit damage (0.17 larvae/plant) and 1.40 percent, followed by the IPM module, which is 1.17 larvae/plant and 4.91 percent. The leaf curl infection was low in farmers practices. 10.82 percent, followed by the IPM module recorded 15.26 percent. Maximum fruit yield of 11200 kg/ha with a comfortable B:C ratio of 2.96 was obtained in the IPM module, followed by farmer practice with a B:C ratio of 2.91.

Lightweight Implementation of the Signal Enhancement Model for Early Wood-Boring Pest Monitoring

Wood-boring pests are one of the most destructive forest pests. However, the early detection of wood-boring pests is extremely difficult because their larvae live in tree trunks and have high invisibility. Borehole listening technology is a new and effective method to detect the larvae of insect pests. It identifies infested trees by analyzing wood-boring vibration signals. However, the collected wood-boring vibration signals are often disturbed by various noises existing in the field environment, which reduces the accuracy of pest detection. Therefore, it is necessary to filter out the noise and enhance the wood-boring vibration signals to facilitate the subsequent identification of pests. The current signal enhancement models are all designed based on deep learning models, which have complex scales, a large number of parameters, high demands for storage resources, large computational complexity, and high time costs. They often run on resource-rich computers or servers, and they are difficult to deploy to resource-limited field environments to realize the real-time monitoring of pests; as well, they have low practicability. Therefore, this study designs and implements two model lightweight optimization algorithms, one is a pre-training pruning algorithm based on masks, and the other is a knowledge distillation algorithm based on the separate transfer of vibration signal knowledge and noise signal knowledge. We apply the two lightweight optimization algorithms to the signal enhancement model T-CENV with good performance outcomes and conduct a series of ablation experiments. The experimental results show that the proposed methods effectively reduce the volume of the T-CENV model, which make them useful for the deployment of signal enhancement models on embedded devices, improve the usability of the model, and help to realize the real-time monitoring of wood-boring pest larvae.

Cry1Ac toxin binding in the velvetbean caterpillar Anticarsia gemmatalis: study of midgut aminopeptidases N.

The velvetbean caterpillar Anticarsia gemmatalis is one of the main soybean defoliators in Brazil. Currently, the main biopesticide used to control insect pests worldwide is the bacteria Bacillus thuringiensis (Bt), which produces entomopathogenic Crystal toxins (Cry) that act in the midgut of susceptible insects, leading them to death. The mode of action of Cry toxins in the midgut involves binding to specific receptors present on the brush border of epithelial cells such as aminopeptidase N (APN), alkaline phosphatase (ALP), cadherin, and others. Mutations in these receptors, among other factors, may be involved in the development of resistance; identification of functional Cry receptors in the midgut of A. gemmatalis is crucial to develop effective strategies to overcome this possible scenario. This study's goal is to characterize APNs of A. gemmatalis and identify a receptor for Cry1Ac in the midgut. The interaction of Bt spores with the midgut epithelium was observed in situ by immunohistochemistry and total aminopeptidase activity was estimated in brush border membrane vesicle (BBMV) samples, presenting higher activity in challenged individuals than in control ones. Ten APN sequences were found in a A. gemmatalis' transcriptome and subjected to different in silico analysis, such as phylogenetic tree, multiple sequence alignment and identification of signal peptide, activity domains and GPI-anchor signal. BBMV proteins from 5th instar larvae were submitted to a ligand blotting using activated Cry1Ac toxin and a commercial anti-Cry polyclonal antibody; corresponding bands of proteins that showed binding to Cry toxin were excised from the SDS-PAGE gel and subjected to mass spectrometry analysis, which resulted in the identification of seven of those APNs. Quantitative PCR was realized to compare expression levels between individuals subjected to sublethal infection with Bt spores and control ones, presenting up- and downregulations upon Bt infection. From these results, we can infer that aminopeptidases N in A. gemmatalis could be involved in the mode of action of Cry toxins in its larval stage.

Assessing the Efficacy of Formulated Organic Biopesticide in Managing Insect Pests in Okra (Abelmoschus esculentus L. Moench)

Assessing the Efficacy of Formulated Organic Biopesticide in Managing Insect Pests in Okra (Abelmoschus esculentus L. Moench)