Helicoverpa Armigera Research Articles

Immobilization of Bacillus thuringiensis Cry1Ac in metal-organic frameworks through biomimetic mineralization for sustainable pest management

Traditional chemical pesticide dosage forms and crude application methods have resulted in low pesticide utilization, increased environmental pollution, and the development of resistance. Compared to traditional pesticides, nanopesticides enhance the efficiency of pesticide utilization and reduce the quantity required, thereby decreasing environmental pollution. Herein, Cry1Ac insecticidal crystal protein from Bacillus thuringiensis Subsp. Kurstaki HD-73 was encapsulated in a metal-organic framework (zeolite imidazolate framework-8, ZIF-8) through biomimetic mineralization to obtain Cry1Ac@ZIF-8 nanopesticides. The Cry1Ac@ZIF-8 nanopesticides exhibited a dodecahedral porous structure, and the introduction of Cry1Ac did not affect the intrinsic crystal structure of ZIF-8. The indoor toxicity analysis revealed that the toxicity of Cry1Ac towards Ostrinia furnacalis (Guenée), Helicoverpa armigera Hubner, and Spodoptera litura Fabricius was not affected by ZIF-8 encapsulation. Surprisingly, Cry1Ac@ZIF-8 still exhibited excellent pest management efficacy even after exposure to heat, UV irradiation, and long-term storage. More importantly, the encapsulation of ZIF-8 significantly enhanced the internal absorption performance of Cry1Ac in maize leaves and extended its persistence period. Thus, ZIF-8 could potentially serve as a promising carrier for the preparation of nanopesticides with enhanced applicability, stability, and persistence period, providing a powerful strategy to improve the application of Cry1Ac in future agricultural pest management.

Elucidating the role of artificial diet on protease enzyme activity in larval midgut of Helicoverpa armigera as influenced by modification of artificial diet by Cry1Ac toxin

Elucidating the role of artificial diet on protease enzyme activity in larval midgut of Helicoverpa armigera as influenced by modification of artificial diet by Cry1Ac toxin

Tyramine-Mediated Hyperactivity Modulates the Dietary Habits in Helicoverpa armigera.

Helicoverpa armigera exhibits extensive variability in feeding habits and food selection. Neuronal regulation of H. armigera feeding behavior is primarily influenced by biogenic amines such as Tyramine (TA) and Octopamine (OA). The molecular responses of H. armigera to dietary challenges in the presence of TA or OA have yet to be studied. This investigation dissects the impact of OA and TA on H. armigera feeding choices and behaviors under non-host nutritional stress. It has been observed that feeding behavior remains unaltered during the exogenous administration of OA and TA through an artificial diet (AD). Ingestion of higher OA or TA concentrations leads to increased mortality. OA and TA treatment in combination with host and non-host diets results in the induction of feeding and higher locomotion toward food, particularly in the case of TA treatment. Increased expression of markers, prominin-like, and tachykinin-related peptide receptor-like transcripts further assessed increased locomotion activity. Insects subjected to a non-host diet with TA treatment exhibited increased feeding and overexpression of the feeding indicator, the Neuropeptide F receptor, and the feeding regulator, Sulfakinin, compared with other conditions. Expression of sensation and biogenic amine synthesis genesis elevated in insects fed a non-host diet in combination with OA or TA. Metabolomics analysis revealed a decreased concentration of the feeding behavior elicitor, dopamine, in insects fed a non-host diet containing TA. This work highlights the complex interplay between biogenic amine functions during dietary stress and suggests the role of tyramine in feeding promotion under stressed conditions.

Genome-wide identification and phylogenetic analysis of the tetraspanin gene family in lepidopteran insects and expression profiling analysis in Helicoverpa armigera.

The tetraspanin gene family encodes cell-surface proteins that span the membrane 4 times and play critical roles in a wide range of biological processes across numerous organisms. Recent findings highlight the involvement of a tetraspanin of the lepidopteran pest Helicoverpa armigera in resistance to Bacillus thuringiensis Cry insecticidal proteins, which are extensively used in transgenic crops. Thus, a better understanding of lepidopteran tetraspanins is urgently needed. In the current study, genome scanning in 10 lepidopteran species identified a total of 283 sequences encoding potential tetraspanins. Based on conserved cysteine patterns in the large extracellular loop and their phylogenetic relationships, these tetraspanins were classified into 8 subfamilies (TspA to TspH). Six ancestral introns were identified within lepidopteran tetraspanin genes. Tetraspanins in TspA, TspB, TspC, and TspD subfamilies exhibit highly similar gene organization, while tetraspanins in the remaining 4 subfamilies exhibited variation in intron loss and/or gain during evolution. Analysis of chromosomal distribution revealed a lepidopteran-specific cluster of 10 to 11 tetraspanins, likely formed by tandem duplication events. Selective pressure analysis indicated negative selection across all orthologous groups, with ω values ranging between 0.004 and 0.362. However, positive selection was identified at 18 sites within TspB5, TspC5, TspE3, and TspF10. Furthermore, spatiotemporal expression analysis of H. armigera tetraspanins demonstrated variable expression levels across different developmental stages and tissues, suggesting diverse functions of tetraspanin members in this globally important insect pest. Our findings establish a solid foundation for subsequent functional investigations of tetraspanins in lepidopteran species.

The novel function of an orphan pheromone receptor reveals the sensory specializations of two potential distinct types of sex pheromones in noctuid moth

Sex pheromones play crucial role in mating behavior of moths, involving intricate recognition mechanisms. While insect chemical biology has extensively studied type I pheromones, type II pheromones remain largely unexplored. This study focused on Helicoverpa armigera, a representative species of noctuid moth, aiming to reassess its sex pheromone composition. Our research unveiled two previously unidentified candidate type II sex pheromones—3Z,6Z,9Z-21:H and 3Z,6Z,9Z-23:H—in H. armigera. Furthermore, we identified HarmOR11 as an orphan pheromone receptor of 3Z,6Z,9Z-21:H. Through AlphaFold2 structural prediction, molecular docking, and molecular dynamics simulations, we elucidated the structural basis and key residues governing the sensory nuances of both type I and type II pheromone receptors, particularly HarmOR11 and HarmOR13. This study not only reveals the presence and recognition of candidate type II pheromones in a noctuid moth, but also establishes a comprehensive structural framework for PRs, contributing to the understanding of connections between evolutionary adaptations and the emergence of new pheromone types.

Assessment of Botanicals against the Fruit Borer (Helicoverpa armigera) on Tomato

Assessment of Botanicals against the Fruit Borer (Helicoverpa armigera) on Tomato

The Main Pests Are Insects and Diseases of Agricultural Crops in the South of Kyrgyzstan

In the south of Kyrgyzstan, the largest areas are occupied by agrocenosis of vegetable, fruit, industrial, and grain crops. The article presents the main pests and pathogens of agricultural crops in the south of Kyrgyzstan. The purpose of the research is to identify the dominant pests and diseases of agricultural crops and to find effective biological measures to combat them in the conditions of southern Kyrgyzstan. In recent years, outbreaks of mass reproduction of tomato mining moth (Tuta absoluta (Meyrick, 1917)) on tomatoes, cherry slimy sawfly (Caliroa cerasi (Linnaeus, 1758)) and cherry fly (Rhagoletis cerasi (Linnaeus, 1758)) on cherries and cherries, Colorado potato beetle (Leptinotarsa decemlineataSay), late blight (Phytophthora infestans (Mont.) de Bary) on potatoes, powdery mildew (Erysiphe cichoracearum f. cucurbitacearumPot.) on vegetables, corn moth (Ostrinia nubilalis Hübner, 1796), bread beetle (Zabrus tenebrioides (Goeze, 1777)) and bug (Eurygaster integriceps Puton, 1881) on cereals, mite (Tetranychus urticae), aphid (Aphidoidea) and cotton scooper (Helicoverpa armigera Hübner) on cotton, phytonomus (Phytonomus variabilis) on perennial grasses, winter scooper (Agrotis segetum (Denis et Schiffermüller) 1775), apple moth (Carpocapsa pomonella (Linnaeus, 1758)), apple moth (Hyponomeuta malinellus (Zeller, 1838)), unpaired silkworm (Lymantria dispar Linnaeus, 1758), curly leaves (Taphrina deformans (Berk.) Tul.), bacterial burn (Erwinia amylovora (Burrill, 1882) Winslow et al., 1920), scab (Venturia inaequalis (Cooke) G. Winter) and powdery mildew on fruit crops, epiphytotic rust diseases (Puccinia) of cereals, oatmeal (Avena fatua) and sunflowers (Barbarea vulgaris) on cereals. An overview of drugs used in crop protection systems is also given. Chemical pesticides still remain the main means of protecting agricultural crops from pests and diseases, in the future, the use of the latest technologies in plant protection, the introduction of new biological preparations into plant protection practice should be used.

Assessing the Efficacy and Economics of Selected Insecticides against Pod Borer [Helicoverpa armigera (Hubner)] on Cowpea [Vigna ungiculata (L.) Walp]

Assessing the Efficacy and Economics of Selected Insecticides against Pod Borer [Helicoverpa armigera (Hubner)] on Cowpea [Vigna ungiculata (L.) Walp]

Weather Parameter’s Impact on Natural Parasitization by Campoletis chlorideae Uchida in Chickpea Ecosystem - New Alluvial Zone of West Bengal

Background: A major biotic constraint in chickpea (Cicer arietinum L.) production is gram pod borer, Helicoverpa armigera (Hübner). However, the population of this pest is reduced to some extent by a solitary endo-larval parasitoid, Campoletis chlorideae Uchida under field conditions. Climate change has a greater impact on natural enemies’ effectiveness used in field-level pest management. Therefore, the present study was conducted to understand the impact of weather factors on C. chlorideae parasitization rate of H. armigera in chickpea grown in the new alluvial agro-climatic zone of West Bengal. Methods: Chickpea was grown in a randomized complete block design (RCBD) with three replications during Rabi 2017-18, 2018-19 and 2019-2020, at Mondouri farm, Bidhan Chandra Krishi Visawavidayala, Mohanpur, West Bengal. To know the most significant weather parameter which influences C. chlorideae parasitization or parasitoid incidence, H. armigera larvae (2nd instar) collected from the field experiment were reared until cocoon formation and parasitization % was correlated with weather parameters and subsequently subjected to stepwise regression analysis. Result: The larval endo-parasitoid, C. chlorideae marked its first appearance from 3rd SMW after the appearance of H. armigera and its activity was high (68% to 72% parasitization) during the flowering to pod initiation stage and thereafter declined gradually. Among the weather variables, only temperature (maximum and minimum) had a consistent and significant negative correlation with C. chlorideae incidence and was responsible for nearly 50% C. chlorideae incidence. An increase in 1°C temperature results in a decrease of 4% parasitoid incidence. Thus, climate change in the near future will have a considerable influence on the overall survival, development and rate of parasitization of parasitoids.

Tinospora malabarica leaf extract fractions-derived silver nanoparticles and their spectral characterisation: evaluation of their toxicity properties against agricultural pests Spodoptera litura and Helicoverpa armigera

ABSTRACT Our study specifically delves into the synthesis of AgNPs utilizing Tinospora malabarica leaf extract fractions (Tm-LMEFs) and explore their efficacy in combating the larvae have progressed to the synthesized AgNPs (Tm-AgNPS) and the leaf methanol extract fractions (LMEFs), our investigation focused on their impact on the targeted larvae species over a 24-h exposure period. Significantly noteworthy mortality rates were observed across all Spodoptera litura and Helicoverpa armigera post-treatment, indicating pronounced efficacy. Notably, the Tm-AgNPS exhibited higher toxicity compared to the LMEFs these selected polyphagous insect pests. Quantitative analysis yielded the highest mortality (98.99%/90.44% and 55.33%/49.60%) values for the synthesized Tm-AgNPs against S. litura and H. armigera, with no observed mortality in the control group. This study marks the first instance of exploring both Tm-LMEFs, Tm-AgNPs and enzyme activity have toxicity properties against selected agriculture pests, highlighting their promising role in pest management and environmental sustainability.

Efficacy of Selected Biopesticides with Chlorantraniliprole against Gram Pod Borer, Helicoverpa armigera (Hubner) on Chickpea

The present investigation was conducted at the research plot of Department of Entomology at CRF, Sam Higginbottom University of Agriculture Technology and Sciences, Prayagraj during the Rabi season of 2023-2024. The experiment was conducted in Randomized Block Design (RBD) using eight treatments each replicated thrice viz., Neem oil 2 % @20ml/lit, Spinosad 45 % SC @0.3ml/lit, NSKE 5% @5ml/lit., Bacillus thurngiensis @2.5 gm/lit, Beauveria bassiana @2.5gm/lit, Emamectin benzoate 5%SG @2ml/lit, Chlorantraniliprole18.5 S @1.5ml/lit and untreated control. Among the biopesticides and insecticides evaluated, Chlorantraniliprole 18.5 SC recorded lowest mean population of pod borer population i.e. (1.79) which was significantly superior over control followed by Spinosad 45 % SC (2.02%), Emamectin benzoate 5%SG (2.23%), Neem oil 2% (2.41%), NSKE 5% SC (2.61%), Bacillus thurngiensis (1.83%) and Beauveria bassiana (2.99%) was least effective among all the treatments. Among the treatment studied the best and most economical treatment was Chlorantraniliprole 18.5SC with highest and cost benefit ratio of 28.3 q/h and 1:3.1 followed by Spinosad 45 % SC %SC 26.7 q/h, 1:3.0, Emamectin benzoate 5%SG 25.8q/h and 1:2.9, Neem oil 2 % 22.5 q/h, 1:2.4, NSKE 5% 21.2 q/h , 1:2.2, Bacillus thurngiensis 17.0 q/h, and 1:1.9, Beauveria bassiana 11.7 q/h, and1:1.2 as compared to control 9.3 q/h and 1:1.1.

IPM IN SOYBEANS: HOW TO REDUCE CROP DAMAGE AND INCREASE PROFIT FOR THE FARMER

The objective of the present work was to implement integrated pest management (IPM) in the soybean crop, comparing it with the management carried out by the farmer during two consecutive seasons. The monitoring of adult lepidopterans was also evaluated using Delta-type traps baited with the sexual pheromones of Spodoptera frugiperda (Bio Spodotera®), Helicoverpa armigera (Bio Helicoverpa®) and Chrysodeixis includens (Bio Pseudoplusia®). Incidence of caterpillars and stinkbugs in soybeans was weekly determined, both in the IPM area and in the farmer, area using the beat cloth method. Insecticide applications in the IPM area were carried out when pest population densities reached the control level, while in the area managed by the farmer, sprayings were carried out at his discretion. Based on the results obtained, we found that adoption of IPM enabled better control of the pests in soybeans, especially for stink bugs, and the number of insecticide applications in soybeans could be reduced, which provides economic and environmental benefits for the farmer. In addition, we found that the sexual pheromones of the three evaluated pest species are effective in capturing their moths.

Native Bacillus thuringiensis isolates against the old-world bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) in Ethiopia

ABSTRACT Chickpea ( Cicer arietinum L.) production in Ethiopia has been seriously constrained by the insect pest, Helicoverpa armigera. Insecticides have been used for decades to control this noxious pest. However, the restriction on chemical insecticides necessitates biological pest control alternatives. Therefore, the present study investigated the effectiveness of native Bacillus thuringiensis (Bt) isolates against Helicoverpa armigera 3rd instar larvae. The treatments consisted of Bt concentrations at the LD90 values, whereas the control plots were sprayed with distilled water and a commercial Bt. var. thuringiensis product. The results revealed statistically (p < 0.05) significant differences between the native Bt isolates and the control plots. Post 1st, pre 2nd and post 2nd Bt sprayed larval populations counted per plant ranged from 0.8 ± 0.3–3.1 ± 0.1, 0.6 ± 0.1–3.6 ± 0.0 and 0.5 ± 0.1–3.6 ± 0.4, respectively. Pod damage (%) and grain yield (t/ha) ranged between 9.7 ± 3.1 and 47.5 ± 9.5, 1.0 ± 0.0 and 2.6 ± 0.5, respectively compared to 47.5 ± 9.5% pod damage and 1.0 ± 0.0 (t/ha) grain yield from the control plots. These results indicate the potential of these bio-insecticides in the management of chickpea pod borer. Future research in Ethiopia should focus on additional collection, screening, characterisation, and testing in field trials.

Seasonal Incidence of &lt;i&gt;Helicoverpa armigera&lt;/i&gt; on Sunflower

Helicoverpa armigera (Hubner). the sunflower head borer, poses a significant threat as it can cause extensive damage by feeding on flower heads and seeds. Its presence can lead to yield losses. Effective IPM strategies are crucial to mitigate the impact of H. armigera infestations and ensure the profitability and sustainability. Monitoring pests is crucial for timely intervention and to minimize crop damage and optimize yields. The present field experiment was carried out during 2021 to study the seasonal incidence of H. armigera on sunflower. Result revealed that incidence of H. armigera was observed during 50th standard meteorological week which reached to peak during 7th SMW. However, it crossed the ETL during 4th SMW. In relation to weather parameters, H. armigera showed positive correlation with maximum temperature (r = 0.557*), while it was negative with evening relative humidity (r = - 0.605*). Further, multiple regression was carried out and it revealed that environmental factors influenced about 70.10% H. armigera incidence in sunflower.

Screening of Pearl Millet Genotypes for Resistance to Shoot Fly &lt;i&gt;Atherigona approximata&lt;/i&gt; Malloch and Ear Head Worm &lt;i&gt;Helicoverpa armigera&lt;/i&gt; (Hubner)

Pearl millet [Pennisetum glaucum (L.) R. Br.] is the sixth most important cereal crop and widely grown on 30 million ha in the arid and semi-arid tropical regions of Asia and Africa. Shoot fly, Atherigona approximata Malloch and ear head worm Helicoverpa armigera Hubner are the key pests of pearl millet and can reduce yield up to 15-20 and 36.67%, respectively. The present study was planned to evaluate 31 promising genotypes for resistance to A. approximata and H. armigera. GHB-744 and HHB-67 were found free from A. approximata infestation while the Raj-171 (3.13%), GHB-732 (3.71%), AHB-1200 (4.30%), GHB-905 (4.41%), Kaveri Super Boss (4.44%) and MPMH-21 (4.81%) were found moderately resistant to A approximata at 28 days after germination. Likewise, AHB-1200 (1.33 larvae/ 5 ear heads) followed by GHB-732 (1.67 larvae/ 5 ear heads) and GHB-905 (2.00 larvae/ 5 ear heads) were found moderately resistant to H. armigera.

Population Dynamics of Gram Pod Borer &lt;i&gt;Helicoverpa armigera&lt;/i&gt; (Hubner)

The population dynamics of gram pod borer Helicoverpa armigera (Hubner) on chickpea was evaluated at the Agricultural Research Farm of B R D P G College, Deoria, Uttar Pradesh during rabi 2022-23. The larval incidence was initially recorded in 6th SMW (first week of February) (2.3 larvae/ plant) with a peak in 11th SMW (third week of March) (10.53 larvae/ plant). Larval incidence on chickpea variety Pusa-261 showed significant positive correlation with maximum temperature (0.837) and minimum temperature (0.804), whereas relative humidity (maximum and minimum) revealed non-significant negative correlation (-0.410), (-0.588), respectively. Correlation between rainfall and larval incidence was found positive and significant (0.734). However, all the weather parameters together contributed 94.18% towards larval incidence.

E93 is involved in regulating larval-pupal metamorphosis and the development of the wing and ovary in Helicoverpa armigera, and it shows great potential for RNAi-based pest control

The ecdysone-induced transcription factor E93 in model insects plays multiple roles in the insect metamorphosis processes, such as remodeling larval tissues and determining adult tissue formation. The knockdown of E93 in insects leads to incomplete metamorphosis, suggesting that E93 is a potential target for pest control. In this study, the HaE93 gene in the cotton bollworm Helicoverpa armigera, a polyphagous pest of various commercial crops worldwide, was identified and found to have high expression in the egg, prepupal, and pupal stages. The injection of dsHaE93 induced about 60% mortality in H. armigera at the larval-pupal stage. About 30% of the H. armigera surviving knockdown of the HaE93 gene showed delayed pupation and developed abnormal wings, and the females developed reduced ovaries. About 90% of the HaE93 knockdown individuals failed to reproduce before they died. The results of qRT-PCR showed that the expression levels of ecdysone primary-response genes, chitin synthesis-related genes, and wing and ovary development-related genes were reduced in HaE93 knockdown H. armigera. These results indicated that HaE93 plays a critical role in larva-pupa-adult metamorphosis and the development of the cuticle, wing, and ovary in female H. armigera by regulating the expression of the associated genes. Bioassays of dsHaE93 administered by either oral delivery or injection showed similar knockdown results, which suggested that HaE93 can be used as a target gene for the RNAi control of the pest H. armigera.

The larva and adult of Helicoverpa armigera use differential gustatory receptors to sense sucrose

Almost all herbivorous insects feed on plants and use sucrose as a feeding stimulant, but the molecular basis of their sucrose reception remains unclear. Helicoverpa armigera as a notorious crop pest worldwide mainly feeds on reproductive organs of many plant species in the larval stage, and its adult draws nectar. In this study, we determined that the sucrose sensory neurons located in the contact chemosensilla on larval maxillary galea were 100–1000 times more sensitive to sucrose than those on adult antennae, tarsi, and proboscis. Using the Xenopus expression system, we discovered that Gr10 highly expressed in the larval sensilla was specifically tuned to sucrose, while Gr6 highly expressed in the adult sensilla responded to fucose, sucrose and fructose. Moreover, using CRISPR/Cas9, we revealed that Gr10 was mainly used by larvae to detect lower sucrose, while Gr6 was primarily used by adults to detect higher sucrose and other saccharides, which results in differences in selectivity and sensitivity between larval and adult sugar sensory neurons. Our results demonstrate the sugar receptors in this moth are evolved to adapt toward the larval and adult foods with different types and amounts of sugar, and fill in a gap in sweet taste of animals.

The larva and adult of Helicoverpa armigera use differential gustatory receptors to sense sucrose.

Almost all herbivorous insects feed on plants and use sucrose as a feeding stimulant, but the molecular basis of their sucrose reception remains unclear. Helicoverpa armigera as a notorious crop pest worldwide mainly feeds on reproductive organs of many plant species in the larval stage, and its adult draws nectar. In this study, we determined that the sucrose sensory neurons located in the contact chemosensilla on larval maxillary galea were 100-1000 times more sensitive to sucrose than those on adult antennae, tarsi, and proboscis. Using the Xenopus expression system, we discovered that Gr10 highly expressed in the larval sensilla was specifically tuned to sucrose, while Gr6 highly expressed in the adult sensilla responded to fucose, sucrose and fructose. Moreover, using CRISPR/Cas9, we revealed that Gr10 was mainly used by larvae to detect lower sucrose, while Gr6 was primarily used by adults to detect higher sucrose and other saccharides, which results in differences in selectivity and sensitivity between larval and adult sugar sensory neurons. Our results demonstrate the sugar receptors in this moth are evolved to adapt toward the larval and adult foods with different types and amounts of sugar, and fill in a gap in sweet taste of animals.

Abundance and Dispersion Indices of Helicoverpa armigera (Lepidoptera: Noctuidae) on Tomato Plant in Nigeria

Helicoverpa armigera is among the major insect pests that pose a threat to tomato production in Nigeria with an insufficient understanding of its population parameters, and available environmentally friendly control materials which are essential for the development of reliable and sustainable management strategies that can minimize the frequent use of synthetic pesticides; which are hazardous to the environment, non-target organism, and humans. The present study was conducted with the objectives of establishing population abundance and dispersion of H. armigera. Surveys were conducted in the savannah agroecological zone of Nigeria through fortnightly field visits to tomato farms from July to September 2019 (rainy season), and month of December 2019 to March 2020 (dry season), making a total of seven (7) and Nine (9) visits respectively. Ten plants were randomly selected and tagged from each farm, for observation of the presence of H. armigera larvae on the upper and lower parts early in the morning (6:00-7:30 am) on all sampling. Numbers found on each plant were counted and recorded with dates. Data obtained were subjected to analysis of variance and the least significant difference (LSD) at 0.05% level of probability was used to separate significant means. Data were further used in calculating the various dispersion indices. The result indicates that H. armigera was higher at 8 weeks after planting and aggregated on the upper part of the plant with a higher population in the dry season. Abundance and dispersion indices of H. armigera on tomato plants reported in this study will provide for appropriate decision-making in designing eco-friendly management of the pest.