The diamondback moth, Plutella xylostella (Linnaeus), remains a major constraint to crucifer production due to its rapid evolution of resistance to insecticides. The present study assessed the resistance status, underlying mechanisms, climatic influences, and spatial patterns of resistance to five newer insecticides viz., emamectin benzoate, novaluron, fipronil, pyridalyl, and indoxacarb, in field populations of P. xylostella collected from six major cabbage-growing regions of India. Laboratory bioassays revealed substantial variation in susceptibility among populations. High resistance was observed to novaluron (RR ranging from 3.6 to 149.1), fipronil (RR ranging from 3.34 to 78.5), and indoxacarb (RR = 6.4–64.5), whereas emamectin benzoate (RR ranging from 2.14 to 84.71) and pyridalyl (RR ranging from 2.5 to 21.65) generally remained more effective across most populations, although localized high resistance to emamectin benzoate and moderate resistance to pyridalyl were detected in specific populations. Synergism assays and biochemical analyses demonstrated that metabolic detoxification, especially via cytochrome P450 monooxygenases and esterases, plays a dominant role in resistance development in highly exposed populations. Pairwise correlation analysis indicated potential cross-resistance among certain insecticides, notably between novaluron and fipronil. Weather-wise correlation analysis showed that temperature extremes, relative humidity, and wind speed significantly influenced insecticide toxicity in an insecticide-specific manner, whereas precipitation and mean temperature had limited effects. Semi-variogram analysis revealed no spatial dependence of resistance, suggesting that local selection pressure and regional management practices predominate rather than distance-dependent spread. Overall, the findings highlight widespread but heterogeneous resistance in P. xylostella populations and emphasize the need for region-specific, climate-aware insecticide resistance management strategies to sustain effective control.
Anopheles peditaeniatus, a member of the Hyrcanus group and the Lesteri subgroup, is widely distributed across the Oriental and Palearctic regions, and it transmits the Japanese encephalitis virus and filariasis to humans. In this study, phylogenetic, phylogeographic, and haplotype network analyses were conducted for An. peditaeniatus (Hyrcanus group) from Tamil Nadu, India. A phylogenetic tree was constructed after sequence quality was analyzed and edges trimmed with BioEdit, followed by multiple sequence alignment using the MUSCLE algorithm and UPGMA cluster method. Sequences with high similarity were retrieved from NCBI GenBank. Neighbour-Joining (NJ) and Maximum Likelihood (ML) techniques with 1000 bootstrap replicates were used to estimate interspecific and intraspecific genetic distances among the different populations, respectively. Genetic structure and diversity were analysed with 81 An. peditaeniatus sequences, which identified 17 haplotypes with moderate overall diversity (Hd = 0.873; π = 0.006). Indian populations showed low variation, dominated by Hap_2, while Sri Lanka exhibited the highest diversity with several unique haplotypes. Thailand, China, and Pakistan showed moderate to high diversity, while Vietnam and Malaysia contributed rare haplotypes despite limited sampling. All sequences clustered and reflected a shared ancestry, suggesting gene flow across South and Southeast Asia but with localized differentiation. Such shared haplotypes are Hap_1, Hap_2, Hap_3, Hap_6, Hap_7, Hap_13 and Hap_14. Negative Fu’s Fs values suggest population expansion or genetic drift, and non-significant Tajima’s D values (P > 0.05) indicate neutrality. Overall, the genetic structure reveals clustered and shared haplotypes with regional hotspots of diversity, underscoring its relevance for vector surveillance and control programs.
Maruca vitrata Fabricius is a destructive insect pest of several legume crops. It has evolved a complex adaptive relationship with its crop environment under exposure to pesticidal sprays, host plant absence, and extreme temperature regimes. The rapid development of insecticide resistance in this pest has become a major challenge to sustainable management. In this context, quantitative real-time PCR (qRT-PCR)-based gene expression analysis of detoxification-related genes is a valuable approach to understand the molecular basis of insecticide resistance and develop improved management strategies. However, accurate normalization of qRT-PCR data relies on the selection of suitable reference genes with stable expression across experimental conditions. In the present study, the expression stability of six candidate reference genes, EF1α, Act, α-tub, GAPDH, Cal, and Ubiq, was evaluated in M. vitrata under diverse biotic and abiotic conditions. Expression data were analyzed using geNorm, NormFinder, BestKeeper, the comparative ΔCt method, and the online tool RefFinder. GeNorm identified Act and GAPDH as the most stable genes (M = 0.765), NormFinder and BestKeeper ranked α-tub as the most stable gene (SV = 0.581; SD ± 1.24), while the ΔCt method also identified Act as the most stable gene (SD = 0.66). Overall analysis indicated Act and α-tub as consistently stable under all the conditions imposed. Pairwise variation analysis using geNorm revealed that two reference genes were sufficient for reliable normalization, as the V2/3 value was below 0.15. Therefore, Act and α-tub could be recommended as suitable reference genes for accurate qRT-PCR normalization in M. vitrata gene expression studies.
As the shortcomings of synthetic chemicals become gradually evident, the dynamics of pest and disease management in modern agriculture are progressively shifting towards environmentally safer alternatives. Biopesticides, such as peptide-based approaches offer attractive alternatives, although their potential remains yet to be fully explored. In this exploratory study, crude venom extracts from previously unexplored Hymenopteran sphecid wasps (Chalybion bengalense, Sceliphron madraspatanum, Ammophila atriceps and Sphex argentatus) were evaluated for their antimicrobial activity against selected plant pathogens. The venom extracts demonstrated prominent antibacterial activity lacking antifungal activity. Among the wasps, C. bengalense exhibited the most significant antibacterial activity against Gram-negative bacteria (Xanthomonas axonopodis pv. citri, X. axonopodis pv. punicae, Ralstonia solanacearum and Pectobacterium carotovorum). LC–MS profiling revealed multiple ionizable molecular features corresponding to compounds in the mass range of 300–3000 Da, indicative of low-molecular-weight bioactive constituents. The comparison of m/z values in the venom sample to the proteomic database and reported literature putatively matched the antimicrobial peptides, Eumenine mastoparan (m/z 1483.1240) and Decoralin (m/z 1257.0773). Further, the exploration of this largely unexplored diversity of antimicrobial compounds offers a valuable opportunity to identify novel bioactive molecules from insect venoms.
The increasing global demand for maintaining sustainable agriculture has focused on the critical role played by endophytic entomopathogenic fungi as dual-purpose microbial agents facilitating plant growth promotion and pest management. Endophytic entomopathogenic fungi as natural endosymbionts, provide multifaceted benefits, such as improving plant growth and nutrient uptake, enhancing tolerance to biotic and abiotic stresses, and protecting the crops against devastating insect pests, pathogens, nematodes, and weeds. Addressing the potential of endophytic entomopathogenic fungi in agriculture has eventually reduced the dependence on toxic agrochemicals, thereby assists to adopt key alarms of environmental safety and agricultural sustainability. Direct application of this category of fungi involves seed treatment, soil inoculation, and foliar sprays, resulting enhancement in plant endosphere colonization, assisting in optimum plant protection and growth promotion. Indirect applications include the potential use of bioformulations, thereby reducing the reliance on toxic chemical fertilizers and pesticides. Customized strategies for integrating entomopathogenic fungi into sustainable pest and disease management frameworks must be generated to boost their use efficiency under field evaluations. These strategies must ensure that the fungi are compatible with other biocontrol agents and recommended dosages of agrochemicals. The integration of advanced technologies, including the genetic engineering, myconanoformulations, artificial intelligence, and the internet of things, alongside Fuzzy logics, has recently revolutionized the strategic advancements in entomopathogenic research for sustainable plant growth promotion and crop protection, leading to the development of climate-smart agriculture.
The implementation of exotic pastures in the Amazon causes drastic negative impacts on its biodiversity. Nevertheless, some species with the ability to colonize pastures may provide important ecosystem services for livestock development in tropical pastures, as in the Amazonian biome. In this study, we evaluated the diversity and assemblage structure of dung beetles, as well as measured their ecological functions (i.e., dung removal and soil excavation) in exotic pastures in the Southwestern Amazon. Dung beetles were sampled using pitfall traps baited with fresh cattle dung, and their ecological functions were measured using experimental arenas during the rainy season. A total of 123 individuals were collected, belonging to five genera and nine species of dung beetles. Dung beetle assemblage had more species of small to medium body size (< 8 mm), with only two species classified as large-bodied. Large and small telecoprids were the most abundant functional groups. The mean (± SE) values for dung removal and soil excavation were 10.9 ± 2.33 g and 15.2 ± 4.22 g, respectively. These findings indicate that only a limited number of dung beetle species are able to colonize exotic pastures in the Southwestern Amazon, predominantly those of small to medium body size, which leads to a reduction of key ecological functions in these environments.
The larvae of Grey Green looper, Thalassodes intaminata Inoue (Lepidoptera: Geometridae) were observed feeding on the new shoots of three major subtropical fruit crops viz., mango, jamun and litchi in the experimental orchards of ICAR-CISH, Lucknow, Uttar Pradesh, India during 2024–25. Through morpho-molecular examinations the identity of the insect was confirmed. The valva basal process of male genitalia is long and spine-like and the harpe was horn-like or triangular sclerite. Aedeagus was slender, with a sclerotized posterior process that is less acute and cornutus was larger. Partial mtCOI sequencing (GenBank Accession No. PV241481) showed 100
A new sand fly species, Evandromyia (Aldamyia) diprimioi sp. nov. Rodrigues, Souza, Santos Andrade Filho, was found in entomological collections carried out in the state of Rio Grande do Sul, South Brazil, and is herein described concerning its morphological traits. This new taxon is closely related to the Evandroi complex but can be distinguished from others of the subgenus E. (Aldamyia) by morphological traits of male and female genitalia. The total number of valid Evandromyia species has increased to 48.
Okra (Abelmoschus esculentus L. Moench) is an economically and nutritionally important vegetable crop in tropical agroecosystems, yet its productivity is frequently constrained by complex pest infestations that remain insufficiently characterized in many local production systems. This two-season field study assessed the occurrence and damage associated with major okra pests in Abak, Akwa Ibom State, Nigeria, using three farmer-managed locations and 180 sampled plants. Two early-maturing okra varieties, Yar-Balle and Yelle, were cultivated under pesticide-free conditions to permit natural pest colonization. Pest surveys were conducted across three crop developmental stages corresponding to seedling, vegetative, and fruiting periods, while damage assessment was based on foliar and pod injury records. Data were analyzed using three-factor factorial analysis of variance (ANOVA) to evaluate the effects of season, location, and sampling period on leaf production and pest-associated damage variables. A diverse assemblage of herbivorous pests, beneficial arthropods, and associated non-insect fauna was recorded throughout the study period. The economically important pest complex was dominated by coleopterans, lepidopteran larvae, heteropteran bugs, and gastropods, with Sylepta derogata, Anomis flava, Earias spp., Helicoverpa armigera, and Limicolaria spp. identified as the principal damage-associated taxa affecting foliage and reproductive structures. Garden snails (Limicolaria spp.) were consistently encountered and caused substantial foliar scraping and perforation, with severe damage reaching approximately 40–65
The bioefficacy of acetone and chloroform extracts of Nerium oleander leaves against early fourth-instar Heliothis armigera was evaluated, demonstrating significant feeding deterrence and toxicity. The extracts showed strong antifeedant potential, as larvae ingested significantly less treated diet than the control, with chloroform extracts displaying the highest antifeedancy at elevated doses. LD₅₀ values for acetone extracts were determined to be 5.370 ml/Kg at 24 h and 1.530 ml/Kg at 96 h. Chloroform extracts exhibited even higher potency, with LD₅₀ values of 1.255 ml/Kg (24 h) and 0.4966 ml/Kg (96 h). Statistical significance was established through Probit analysis and regression equations, confirming the dose-dependent toxic effects. Histological examination of the larval midgut following exposure to LD₅₀ concentrations revealed severe damage, including epithelial shrinkage, extensive vacuolization, disintegration of columnar epithelial cells, and the detachment of the basement membrane. These structural alterations severely impaired digestive and absorptive functions, causing nutritional deficiency and overall growth retardation. The results highlight the potential of N. oleander leaf extracts as a potent, plant-derived biopesticide for sustainable pest management.
Spilarctia obliqua Walker known for its rapid defoliation of crops, is best controlled during the early larval stages when the caterpillars are more vulnerable to insecticides. The main aim of the study was to determine the effective sprays of newer and combination insecticides against S. obliqua in castor. Therefore, field experiment was conducted during the Kharif 2024–2025 cropping season at the Centre for Oilseeds Research, S.D. Agricultural University, Sardarkrushinagar, Gujarat, India. Seven insecticides belonging to different classes were evaluated for their efficacy against S. obliqua. Among these, chlorantraniliprole 18.5
In La Réunion, pineapple is the main fruit crop, but it is threatened by Pineapple Mealybug Wilt-associated Viruses, which are vectored by Dysmicoccus brevipes (Cockerell, 1893). In a context where control methods are drastically limited, new management strategies must be examined, including the use of local natural enemies. In this study, we evaluated the potential of three predator species present in La Réunion and known to prey on mealybugs as biological control agents of D. brevipes: the ladybirds Exochomus laeviusculus Weise, 1909 (Coleoptera: Coccinellidae) and Nephus apolonia Magro Almeida, 2020 (Coleoptera: Coccinellidae) and the brown lacewing Psectra iniqua (Hagen, 1859) (Neuroptera: Hemerobiidae). Stage-specific predation assays were conducted under laboratory conditions using four developmental stages of D. brevipes, and predator development was monitored over a 30-day period. Among the three species tested, E. laeviusculus exhibited the highest predation rates and was the only predator able to complete its development on D. brevipes. Predation was significantly higher on first- and second-instar nymphs than on older nymphs and adults, indicating a preference for early developmental stages. Conversely, N. apolonia and P. iniqua failed to complete development on D. brevipes, with predation restricted to adults feeding on early developmental stages of the pineapple mealybug.
Psyllids (Hemiptera: Psylloidea) are sap-sucking insects inducing severe damages to their host plants. The medicinal plant named Margaritaria discoidea (Phylanthaceae) associated with Cacopsylla oku nov. sp. as pest insect induces necrosis of the leaves and stunt the growth of shoots of the host plant. The aim of this study is to describe and identify the psyllid associated to M. discoidea belonging to Cacopsylla genus. Adults were collected from Oku and Bambui localities (Cameroon) with the aid of a sweep net of 0.5 mm mesh size and mouth aspirator. They were described from the illustrated diagrams made with the aid of microscope as well as the morphological comparison with previously described species. The morphological examination showed that the Cacopsylla oku shares similarities with other Cacopsylla species in the structure of the genal process, antennae and forewings. It differs from others species on that the internal margin of the paramere incurved forming V-shaped structure with a distal external margin slightly expanded and truncate apex, distal portion of aedeagus sub-apically incised with rounded and puffy apex, absence of radular spinules on m1 cell of forewing; the number of setae in the costal margin of the hindwing; the number of basal spines on the metatibia.
Canine demodicosis is an inflammatory parasitic skin disease characterized by the overgrowth of Demodex spp. mites in immunocompromised or genetically predisposed dogs. The present study was undertaken to determine the occurrence of Demodex forms, evaluate associated factors, assess diagnostic approaches, and evaluate the therapeutic response of selected miticidal treatments in canine demodicosis. A total of 269 client-owned dogs suspected of demodicosis were examined between May and October 2024 at the Veterinary Clinical Complex, College of Veterinary Science and Animal Husbandry, NDVSU, Jabalpur. Demodicosis was diagnosed in 29/269 (10.78
Termites are eusocial cockroaches in the order Blattodea, are being considered as ecological engineers, play an immense ecological role in tropical ecosystems and some being potential pests of trees. Microcerotermes Silvestri is one of the economically important genera known to contain many pestiferous termite species. The termite genus Microcerotermes in Karnataka is reviewed, resulting in the record of seven species: viz., M. annandalei Silvestri, M. beesoni Snyder, M. cameroni Snyder, M. fletcheri Holmgren and Holmgren, M. kudremukhae Chhotani, M. minor Holmgren and M. pakistanicus Akhtar. As a part of taxonomic studies of termites, a total of 41 samples of the genus were collected across Karnataka. Of the species collected, M. cameroni (36.59
The Diamondback moth (DBM) Plutella xylostella (L.) (Lepidoptera: Plutellidae) immatures are responsible for substantial losses to crucifer crops worldwide. For their management at field conditions, frequent use of insecticides is the most common and preferred method which has resulted in resistance development, increased residues in food chain, and significant impacts on non-target species. Present study attempts to evaluate resistance status of different diamondback moth field populations toward several commercially available insecticides. Results revealed that all tested P. xylostella populations has no resistance toward Bacillus thuringiensis and emamectin benzoate. However, moderate to high levels of resistance for relatively new insecticides (pyrifluquinazon, spintoram, thiamethoxam+ chlorantraniliprole) was detected in all populations. Extremely high levels of resistance were observed against lufenuron, lambda-cyhalothrin, profenofos and chlorantraniliprole (> 160 RR). Age-Stage Two-Sex life table analysis suggested decrease in fecundity (89.9 ± 15.2 egg/individual), gross reproductive rate (190 ± 25.7) and mean generation time (T) (26.0 ± 0.21) in field populations as compared to susceptible (Arid-PK). Insight in resistance monitoring of the P. xylostella field populations and the associated fitness costs will help toward wise and rotational use of available insecticides for its management.
Maize is a principal staple crop in Ethiopia, serving as a cornerstone for food security and a vital source of income for smallholder farmers. However, its post‑harvest stability and quality are compromised by biophysical factors during storage, particularly maize weevil infestation, kernel breakage, and prolonged storage. This study examined the combined effects of storage insects, kernel breakage, and storage duration on post‑harvest deterioration parameters and mycotoxin accumulation. The experiments were conducted using a Completely Randomized Design (CRD) with three replications. Treatments consisted of maize samples containing 0
Dung beetles provide essential ecosystem services, yet they remain poorly studied in Southeast Asia, particularly regarding their attraction to different carrion bait types. This study investigated the effectiveness of four carrion baits: squid, prawn, fish, and chicken for sampling dung beetle assemblages in a semi-evergreen forest in Cambodia. A total of 1,935 individuals, representing 38 morphospecies across seven genera, were collected using 128 baited pitfall traps during the rainy season. Onthophagus was the most diverse and abundant genus, comprising over 55
A comprehensive assessment of eri silkworm nutrition and host plant suitability is essential for optimizing rearing practices. In the current study, food consumption and conversion efficiency of eri silkworm Samia ricini (Donovan) were studied on castor, tapioca, and kesseru. Growth rate, consumption, and assimilation of food in five larval instars were analyzed. The total larval duration comprising five instar stages were found to complete in 18.33 ± 0.41, 19.92 ± 0.38, and 21.00 ± 0.45 days on castor, tapioca, and kesseru respectively. The ingesta recorded was significantly higher on the primary host castor (34.89 ± 1.15 g) as compared to tapioca (30.35 ± 0.94 g) and kesseru (29.49 ± 1.16 g). The tissue growth rate was recorded on par for the first four instars on the three hosts studied. However, fifth-instar weight gain showed significant differences among the hosts. During the fifth instar, high feeding and assimilation rates were recorded in all the hosts studied, to meet the high energy demands of metabolic processes involved in synthesizing and spinning the cocoon as a protection for the succeeding non-feeding pupal stage. The single cocoon weight, pupal weight, and shell weight were found to be superior on castor, followed by tapioca and kesseru. However, the shell ratio percentage was found to be on par for all three hosts. In conclusion, the study demonstrated that castor host plants yielded the highest cocoon, pupal, and shell weights, compared to tapioca and kesseru. However, the shell ratio percentage was consistent across all three hosts. Additionally, the reproductive success of the non-feeding adult stage was linked to food energy accumulated during the larval phase. The reproductive phase study of the emerged adults reared on three hosts revealed that the effective egg production was on par on all three hosts, suggesting effective utilization of alternate hosts for maximizing eri seed production. This study aims to provide valuable insights into the energy budget and economic parameters that influence eri silkworm rearing ultimately contributing towards improved production efficiency.
