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A laboratory experiment was conducted at ICAR-National Bureau of Agricultural Insect Resources, Bengaluru to study the behavioural response of Trichogramma achaea towards healthy, conspecifics (Tuta absoluta oviposited on Tuta absoluta infested plants) and heterospecifics (Tuta absoluta oviposited on Liriomyza trifolii infested plants) tomato plants by choice and no-choice parasitization assays and olfactometer studies. Headspace volatiles were collected from tomato plants oviposited by conspecifics, heterospecifics and healthy plants, analysed using gas chromatography-mass spectrometry (GC-MS) where 14, 17 and 8 volatile organic compounds were detected respectively. Electrophysiological compounds and antennal response of T. achaea were identified using gas chromatography-electro-antennographic detector (GC-EAD). EAD active compounds of T. achaea were 3-Hexanol, α-phellandrene, trans-β- ocimene, pentacosane and γ-terpinene. [ABSTRACT FROM AUTHOR]

House fly Musca domestica L. is a pest of humans, poultry, and livestock across the world. Dependence on chemical insecticides to contain the flies provided varying results and their continued use has led to development of insecticide resistance. Bioactive compounds in plants are an alternative source to manage M. domestica. Lemon grass, Cymbopogon citratus Stapf essential oil caused fumigant toxicity to eggs (LC50 1.299 mg/dm³) and adults (16.56 mg/ dm³). The C. citratus EO caused larval repellence. Polyvinylpyrrolidone when used as polymer matrix to load C. citratus at 1:1, 1:2, and 1:3 caused toxicity to flies for a longer period as compared to use of EO alone. The EO loaded in polymer matrix had a slower dissipation, EO+ PVP polymer mixed at 1:3 retained over 80% of EO after 72 hr when exposed to 60oC. EO, whilst EO alone without a dispenser dissipated in 3 hr. The biological effect of C. citratus EO on M. domestica can be enhanced for a longer period if loaded into a polymer matrix and this would be an effective strategy to manage M. domestica. [ABSTRACT FROM AUTHOR]

Housefly, Musca domestica is used as an alternate host to rear a eulophid, Nesolynx thymus (Girault), a pupal parasitoid of the tachinid fly, Exorista bombycis (Louis) which in turn is an endolarval parasitoid of Bombyx mori (L.). An attempt was made to evaluate the host factors like pupal size, age and exposure periods of N. thymus for developing robust mass multiplication methods. The host size had significant effect on mean parasitism by N. thymus. Mated females of N. thymus when exposed to host pupae of varying size, revealed that mean per cent parasitisation was significantly higher (74%) in large sized pupae having a volume of 263.89 mm3. Regarding host age, 24 - 48 h old host pupae had higher level of parasitism (65%) by N. thymus. The parasitism rate declined with an increase in host age after 72 h. In field evaluation, release of N. thymus at weekly interval resulted in the reduction of housefly population as evinced from the higher parasitism (56 %) of the sentinel cards placed in the treated poultry sheds. The information on host factors generated will help to enhance the mass multiplication of parasitoid for the release of which would aid to bring down the M. domestica population in poultry and dairy units. [ABSTRACT FROM AUTHOR]

The present study highlights the importance of herbivore induced plant volatiles (HIPVs) in attracting the cetoniid beetles, Protaetia alboguttata (Vigors) to ripe conspecific damaged Carissa carandas L.fruits. Olfactometer assays revealed that volatiles from damaged fruits are significantly attractive to the adult beetles of P. alboguttata. Gas chromatography electroantenno-detection studies revealed that presence of a-copaene and carvacryl acetate in the damaged C. carandas fruits that might be involved in guiding the adult P. alboguttata beetles to their host plants. [ABSTRACT FROM AUTHOR]

Red palm weevil (RPW) has been a devastating pest of the palms. Originally a pest of coconut palm in India, it has spread across to various hosts. Mortality caused to host by its damage has caused RPW to gain pest of national interest in many countries. With limited success attained using the current management practices that includes mechanical and chemical control methods, semiochemicals are gaining popularity by growers mainly due to desirable outcome and being eco-friendly in the pest management. R. ferrugineus weevils are attracted to early fermentation volatiles feeding on which they produce aggregation pheromone attracting their conspecifics. Use of pheromone in isolation has limited success in field, use of food baits in tandem with pheromone strongly enhances the attraction of the weevil. Use of food bait as such in traps needs frequent servicing and this is overcome by identifying the blends derived from food bait and using them in lieu of food baits as such will reduce the need to servicing of traps at frequent intervals. The efficacy of semiochemicals is enhanced by identifying the nanomatrix for controlled delivery that would aid in better spatio temporal release there by increasing the field life of the lure over the conventional polymer-based dispensers. Synergism to pheromone by the volatiles emanating from palm tissues and food bait coupled with improved delivery matrix will scaleup the use of pheromone by farmers there by reducing the dependence on chemical insecticides for RPW management. [ABSTRACT FROM AUTHOR]

High percentage of Homalotylus turkmenicus Myartseva (Hymenoptera: Encyrtidae) parasitizing Hyperaspis maindroni Sicard (Coleoptera: Coccinellidae) predating on the colonies of the Cassava Mealybug (CMB) Phenacoccus manihoti Matile-Ferrero (Hemiptera: Pseudococcidae) is observed in southern India. In the present study, cautionary note on the presence of H. turkmenicus in the food web of insects associated with the CMB and brief diagnosis of the parasitoid is presented for quick identification. The parasitism of Hy. maindroni grubs by H. turkmenicus ranged from 65.67 to 80.95 per cent. However, no primary parasitoid of the cassava mealybug was observed so far. [ABSTRACT FROM AUTHOR]

Studies on Zaniothrips ricini relating to sexual and parthenogenetic reproduction, life cycle, soil pupation, effect of RH and temperature on pupation as well as the three types of migration (i) plant to soil (ii) soil to plant (iii) plant to plant and within plants are discussed. Periodicity of infestation on the castor plant as well as the alternative hosts Datura stramonium and Calotropis gigantean have also been highlighted. The roles of the mantid predator Haldwania lilliputana and the larval parasite Ceranisus menes are also indicated. [ABSTRACT FROM AUTHOR]

Innate recognition templates (IRTs) in insects are developed through many years of evolution. Here we investigated olfactory cues mediating oviposition behavior in the oriental fruit fly, Bactrocera dorsalis, and their role in triggering an IRT for oviposition site recognition. Behavioral assays with electrophysiologically active compounds from a preferred host, mango, revealed that one of the volatiles tested, γ-octalactone, had a powerful effect in eliciting oviposition by gravid B. dorsalis females. Electrophysiological responses were obtained and flies clearly differentiated between treated and untreated substrates over a wide range of concentrations of γ-octalactone. It triggered an innate response in flies, overriding inputs from other modalities required for oviposition site evaluation. A complex blend of mango volatiles not containing γ-octalactone elicited low levels of oviposition, whereas γ-octalactone alone elicited more oviposition response. Naïve flies with different rearing histories showed similar responses to γ-octalactone. Taken together, these results indicate that oviposition site selection in B. dorsalis is mediated through an IRT tuned to γ-octalactone. Our study provides empirical data on a cue underpinning innate behavior and may also find use in control operations against this invasive horticultural pest.

The article presents the highlights of the "Semiochemicals for Borer Pest Management" meeting by the Indian Council of Agricultural Research-National Bureau of Agricultural Insect Resources (ICAR-NBAIR) in Bengalaru, India on August 6, 2015. Topics include the use of semiochemicals in borer pest management, nanotechnology, and semiochemical research. Presenters include ICAR-NBAIR's N. Bakthavatsalam, Kesavan Subaharan, and Abraham Verghese.

Increased globalization and trade have made India a target for entry of many new alien insect pests. One such unintentional recent introduction is the cassava mealybug (CMB), Phenacoccus manihoti on cassava. Monitoring on the occurrence and damage potential of CMB on cassava was undertaken during 2020. Among the places surveyed, maximum damage score (4–5) and density of the mealybug (>1000/shoot tip) were recorded in Salem and Namakkal districts of Tamil Nadu and Thrissur district of Kerala. In the absence of effective native natural enemies and other methods of control, CMB might pose a major crisis to the cassava industry in India. The prospects of its suppression by classical biological control are quite vibrant and the initiative to import the parasitoid wasp, Anagyrus lopezi from Thailand and the Republic of Benin is already being taken by ICAR-NBAIR, Bengaluru, India. [ABSTRACT FROM AUTHOR]

Fall armyworm (FAW; Spodoptera frugiperda (J. E. Smith)) is emerging as the most destructive pest of maize in India since its report in May 2018. Its rapid spread to more than 90% of maize-growing areas of diverse agro-ecologies of India within a span of 16 months presents a major challenge to smallholder maize farmers, maize-based industry, as well as food and nutritional security. FAW has been reported from other crops as well like sorghum and millets with varied proportion of economic damage. In this review, the transboundary movement of FAW, role of ecology, its spread and damage are discussed. Management of FAW by developing and deploying various pest management tools is elaborated. The role of agroecological measures for reducing FAW damage with African experiences has also been highlighted. [ABSTRACT FROM AUTHOR]

Aedes aegypti is the main vector of yellow fever, chikungunya, Zika, and dengue worldwide and is managed by using chemical insecticides. Though effective, their indiscriminate use brings in associated problems on safety to non-target and the environment. This supports the use of plant-based essential oil (EO) formulations as they are safe to use with limited effect on non-target organisms. Quick volatility and degradation of EO are a hurdle in its use; the present study attempts to develop nanoemulsions (NE) of Trachyspermum ammi EO and its constituent thymol using Tween 80 as surfactant by ultrasonication method. The NE of EO had droplet size ranging from 65 ± 0.7 to 83 ± 0.09 nm and a poly dispersity index (PDI) value of 0.18 ± 0.003 to 0.20 ± 0.07 from 1 to 60 days of storage. The NE of thymol showed a droplet size ranging from 167 ± 1 to 230 ± 1 nm and PDI value of 0.30 ± 0.03 to 0.40 ± 0.008 from 1 to 60 days of storage. The droplet shape of both NEs appeared spherical under a transmission electron microscope (TEM). The larvicidal effect of NEs of EO and thymol was better than BEs (Bulk emulsion) of EO and thymol against Ae. aegypti. Among the NEs, thymol (LC 50 34.89 ppm) had better larvicidal action than EO (LC 50 46.73 ppm). Exposure to NEs of EO and thymol causes the shrinkage of the larval cuticle and inhibited the acetylcholinesterase (AChE) activity in Ae. aegypti. Our findings show the enhanced effect of NEs over BEs which facilitate its use as an alternative control measure for Ae. aegypti., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: The occurrence of Spodoptera frugiperda (J.E. Smith) in Asia was reported for the first time from Karnataka in 2018. This pest is widely distributed in India, causing significant damage to maize. Management of this recent invasive pest in maize-growing regions of India relies on chemical control. Resistance is the greatest obstacle to the successful use of chemical insecticides to control this pest. Indiscriminate use of chemical insecticides destroys beneficial natural enemies, therefore effective and sustainable alternative control strategies are needed. In this case, the use of biological control agents is the alternative option to mitigate this pest. Thus, this study aimed to select virulent entomopathogenic nematodes (EPNs) isolates based on the laboratory assay and further to test the efficacy of virulent isolates in the field conditions along with commonly used chemical insecticide emamectin benzoate against S. frugiperda., Results: Laboratory results revealed that both Heterorhabditis indica 1 NBAIIH38 and Steinernema carpocapsae NBAIRS59 caused 100% mortality in third- and fourth-instar larvae of S. frugiperda, while these two species caused 85% and 72% mortality in pupae, respectively. When pupae of S. frugiperda were exposed to EPNs, pupae died after metamorphosis to malformed adults. All the nematode species were able to penetrate and reproduce within S. frugiperda larvae, but the reproduction rate for Heterorhabditids was higher than that of Steinernematids. Field trial results showed that H. indica 1 NBAIIH38 significantly reduced the number of larvae and leaf damage scores compared to S. carpocapsae NBAIRS59. Emamectin benzoate was more effective in reducing the larval population compared to EPN species. The cob yield was significantly higher in EPN- and emamectin benzoate-treated plots than in untreated control plots., Conclusion: Overall, these experiments suggest H. indica 1 NBAIIH38 is a promising biocontrol agent against S. frugiperda in maize production. © 2022 Society of Chemical Industry., (© 2022 Society of Chemical Industry.)

The indiscriminate use of pesticides leads to irreparable damage to the ecosystem, which motivates for sustainable alternatives like pheromone-assisted pest management. The tomato pinworm Tuta absoluta is a major threat to tomato cultivation. Moreover, its green management technology uses a pheromone trap that has a short field life. To overcome this problem, a pheromone composite with graphene oxide (GO) and amine-modified graphene oxide (AGO) that can extend the diffusion path has been developed. The composite stimulates an effective electrophysiological response in the antenna, which results in trapping of a significantly higher number of insects as compared to the commercial septa, thus qualifying it for field evaluation. Compared to AGO, the GO composite has pheromones assembled into a multilayer, which increases the pheromone diffusion path. This in turn resulted in the extension of the pheromone life that proportionally increased the pest trapped. This technique will be beneficial to farmers as they have longer field efficacy to keep the pest damage low in an environmentally friendly manner.

Ocimum basilicum essential oil (EO) was evaluated for its biological effects on M. domestica. Characterization of O. basilicum EO revealed the presence of methyl chavicol (70.93%), linalool (9.34%), epi-α-cadinol (3.69 %), methyl eugenol (2.48%), γ-cadinene (1.67%), 1,8-cineole (1.30%) and (E)-β-ocimene (1.11%). The basil EO and its constituents methyl chavicol and linalool elicited a neuronal response in female adults of M. domestica. Adult female flies showed reduced preference to food source laced with basil EO and methyl chavicol. Substrates treated with EO and methyl chavicol at 0.25% resulted in an oviposition deterrence of over 80%. A large ovicidal effect was found for O. basilicum EO (EC 50 9.74 mg/dm 3 ) followed by methyl chavicol (EC 50 10.67 mg/dm 3 ) and linalool (EC 50 13.57 mg/dm 3 ). Adults exposed to EO (LD 50 10.01 μg/adult) were more susceptible to contact toxicity than to methyl chavicol and linalool (LD 50 13.62 μg/adult and LD 50 43.12 μg/adult respectively). EO and its constituents methyl chavicol and linalool also induced the detoxifying enzymes Carboxyl esterase (Car E) and Glutathione S - transferases (GST)., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Housefly, Musca domestica L. is a pest of public health importance and is responsible for spreading diseases like typhoid, diarrhoea, plague etc. Indiscriminate reliance on synthetic insecticides has led to development of insecticide resistance and ill effect to humans and nontarget animals. This demands an alternative and safer pest control option. This study evaluates the biological effect of Piper betle L essential oil and its constituent eugenol, eugenol acetate, and β - caryophyllene on the housefly. The major components present in P. betel EO were safrole (44.25%), eugenol (5.16%), β -caryophyllene (5.98%), β -selinene (5.93%), α-selinene (5.27%) and eugenol acetate (9.77%). Eugenol caused 4.5fold higher ovicidal activity (EC 50 86.99 μg/ml) than P. betle EO (EC 50 390.37 μg/ml). Eugenol caused fumigant toxicity to adults (LC 50 88.38 mg/dm 3 ). On contact toxicity by topical application, eugenol acetate, eugenol and β-caryophyllene caused higher mortality to larval and adult stages than EO. FESEM (Field Emission Scanning Electron Microscope) images reveal that exposure to P. betle EO causes the shrinkage of the larval cuticle. Both EO and eugenol induced the detoxifying enzymes Carboxyl esterase (Car E) and Glutathione S - transferases (GST) in larvae and adults. EO and eugenol at 0.2% caused effective repellence and oviposition deterrence to M. domestica adults and this merits their use as alternative strategy to manage M. domestica., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Recent studies proved that the biofumigants could be an alternative to chemical fumigants against stored grain insect pests. For this reason, it is necessary to understand the mode of action of biofumigants. In the present study the prospectus of utilising Lantana camara as a potent fumigant insecticide is being discussed. Inhibition of acetylcholinesterase (AChE) by Coumaran, an active ingredient extracted from the plant L. camara, was studied. The biofumigant was used as an enzyme inhibitor and acetylthiocholine iodide as a substrate along with Ellman's reagent to carry out the reactions. The in vivo inhibition was observed in both dose dependent and time dependent in case of housefly, and the nervous tissue (ganglion) and the whole insect homogenate of stored grain insect exposed to Coumaran. The possible mode of action of Coumaran as an acetylcholinesterase inhibitor is discussed.