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Sub-lethal baculoviral infections are associated with several developmental and reproductive defects but the mechanism behind these defects is not well understood. Here, we investigated the reproductive defects induced by sub-lethal infection of Spodoptera frugiperda nucleopolyhedrovirus (SfNPV) in Spodoptera frugiperda (J.E.Smith) adults. We observed significantly less oviposition, loss of fecundity and egg hatchability in surviving adults after SfNPV infection. Reciprocal crosses with both the genders suggested that the infection of either sex could result in the fertility defects. An investigation of anatomy of reproductive of the surviving females suggested minor defects but confirmed reduced mating with infected males. Oviposition defects were observed in the infected group in spite of successful mating. Differential transcriptome analysis of infertile females from sub-lethally infected group revealed alteration of reproductive, developmental and behavioural pathway genes in comparison to control. We have also investigated the involvement of hormonal genes and piRNAs in their contribution to reproductive defects post sub-lethal baculoviral infection. This study will shed some light on the molecular mechanisms behind the sub-lethal effects observed in the surviving adults post baculovirus infection and will be useful to understand the infertility pathways in insects.

Maconellicoccus hirsutus is a destructive pest which causes severe losses of agricultural and horticultural crops. For the management of M. hirsutus, many insecticides have been used and it has been exposed to insufficient dosage or uneven spray coverage which resulted in the development of insecticide resistance. Xenobiotic metabolism can be better understood with the help of gene expression studies by unveiling the underlying molecular mechanisms. The qRT-PCR is the simplest method to analyse gene expression, however, it highly relies on suitable reference genes concerning the different experimental conditions.We evaluated the stability of five reference genes in two sets of experimental conditions viz. developmental stages (nymphs and adults) and agrochemical stress (GA3 and Buprofezin sprayed) against M. hirsutus, using different softwares-NormFinder, geNorm, BestKeeper, and RefFinder. The study revealed that ATP51a and GAPDH can be used as reference genes for gene expression studies when exposed to Gibberellic acid. Additionally, the study revealed that the ideal pair of reference genes for data validation in M. hirsutus treated with Buprofezin was GAPDH and β-tubulin. The ideal reference gene combination for various developmental stages was found to be 28S and Actin.According to the study, GAPDH can be utilized as a reliable reference gene in the agrochemical (GA3 and Buprofezin) exposure set. The genes can be utilized as a suitable reference for qRT-PCR gene expression studies of xenobiotic metabolism to understand the underlying molecular mechanism, which will help further to design suitable management strategies.

Aim: The present study aimed at reporting the occurrence of pest, Pyrausta panopealis on sweet basil Ocimum basilicum. The biological parameters and population dynamics of the pest was studied on its newly reported host plant. Methodology: Description of P. panopealis was done using morphological and molecular approaches. Male and female genitalia of adults were dissected for morphological identification. DNA was isolated from insect sample (adult legs) and amplified using mtCOI primers (LCO 1490; HCO 2198). The larva of P. panopealis was reared on sweet basil under laboratory conditions for observing the growth parameters. Results: Male genitalia with distinct spoon-shaped clasper; female genitalia corpus bursae with appendix bursa. The sequenced DNA product was submitted to NCBI- GenBank (Accession No: Mk559412). The mean incubation period, larval period and pupal period of the pest was 3.19 days; 13.81 days; 5.40 and 6.27 days. The total life span of male and female insects ranged from 22 to 33 days and 24 to 35 days, respectively. The fecundity of adult varied from 91 to 131 (average 111.75 eggs). The peak population of pest (11.5 larvae/ plant) was recorded during 32nd standard meteorological week, during which all the observed plants were infested by larvae of P. panopealis. Interpretation: This is the first report of association between P. panopealis and sweet basil. The data on life cycle parameters, seasonal incidence and severity can be used for developing integrated pest management strategies to P. panopealis on sweet basil. Key words: Genitalia, Perilla leaf moth, Pyrausta panopealis, Seasonal incidence, Sweet basil

The cassava mealybug, Phenacoccus manihoti Matile-Ferrero is one of the most serious pests of cassava worldwide, which got recently introduced into India (traced in Kerala) as a potential invasive pest. Studies were carried out to record the incidence of mealybug, P. manihoti and its natural enemies on different varieties of cassava in Namakkal dt. of Tamil Nadu during June 2020. The observations were taken in the field in situ as well in the collected mealybug infested twigs in the laboratory. Results revealed that all the three surveyed cassava varieties viz. , Mulluvadi, Thailand white and Shree Atulya were found severely infested with cassava mealybug. A huge number of coccinellid beetles were collected from the P. manihoti colonies, which were identified as Hyperaspis maindroni Sicard, 1929 (Coccinellidae:Coccinellinae:Hyperaspidini). Molecular characterization of both grub and adult beetle of H. maindroni was carried out to confirm its identity.

Fall Armyworm, Spodoptera frugiperda (J E Smith) (Lepidoptera, Noctuidae) is native to the tropical and subtropical region of America. Being a polyphagous pest known to cause major damage to economically important cultivated grasses. This insect is one of the most important pests of maize, being firstly registered in the India in 2018 and it causes a 33% yield loss in the plant production. The use of chemical pesticides as a prophylactic method causes some problems such as ecological instability, pollution, high costs and death of natural enemies. In the current study, screening of native B. thuringiensis isolates and their insecticidal activities were tested against the 2nd instar larvae of maize fall armyworm, Spodoptera frugiperda under laboratory condition. Preliminary bioassay was conducted using diet incorporation method and treated with spore crystal lysates prepared from the native Bacillus thuringiensis isolates. Upon screening 50.0 per cent (of the B. thuringiensis isolates exhibited mortality in the range of 26-50 per cent while 10.0 per cent of the B. thuringiensis isolates showed more than 75 per cent mortality after 7 days of exposure. Among the seventy isolates, Bt-Oa1 and Bt-257 recorded maximum of 86.84% mortality after 7 days after treatment.

Cotton is one of world’s most essential fiber crops having global significance. Several biotic and abiotic stresses are constraints in cotton production including the bollworm complex and sucking pests. Among sucking pests, the cotton leafhopper, Amrasca biguttula biguttula (Ishida) is a devastating pest causing both quantitative and qualitative losses. After the introduction of Bt cotton, there was a check to the bollworm complex. But, the sucking pest complex particularly leafhoppers increased gradually reaching economic injury levels. The rampant application of insecticides to control sucking pests has led to the development of pest resistance to insecticides with different mode of action world over. Among the various mechanisms of resistance, the metabolic resistance plays a vital role. In order to determine the enzyme activity viz., cytochrome P450 monooxygenase, carboxyl esterase and glutathione S-transferase, for which the biochemical analysis was done by using field collected and laboratory reared population of this pest. The results revealed that, the activity of detoxification enzymes was significantly higher in the field collected population as compared to the laboratory population. The specific activity of cytochrome P450 monooxygenase (14.88 nmol/min/mg protein), carboxyl esterase (1321.97 nmol/min/mg protein) and glutathione S-transferase (1021.83 nmol/min/mg protein) in field collected population as compared to cytochrome P450 monooxygenase (12.02 nmol/min/mg protein), carboxyl esterase (1022.82 nmol/min/mg protein) and glutathione S-transferase (310.26 nmol/min/mg protein) in susceptible laboratory reared population of A. biguttula biguttula. This clearly shows that, these three xenobiotic enzymes are responsible for the detoxification of insecticides in the field population of this notorious pest.

Genome-wide analysis of cytochrome P450 monooxygenase (CYP) genes from the advanced genome project of the Leucinodes orbonalis and the expression analysis provided significant information about the metabolism mediated insecticide resistance. A total of 72 putative CYP genes were identified from the genome and transcriptome of L. orbonalis. The genes were classified under 30 families and 46 sub-families based on the standard nomenclature. In the present study, a novel CYP gene, CYP324F1 was identified and it has not been reported from any other living system so far. Biochemical assays showed enhanced titers (5.81-18.5 fold) of O-demethylase of cytochrome p450 monooxygenase in five field-collected populations. We selected 34 homologous CYP gene sequences, seemed to be involved in insecticide resistance for primer design and quantitative real time PCR studies. Among the many over-expressed genes (>10 fold), the expression levels of CYP324F1 and CYP306A1 were prominent across all the field populations as compared to the susceptible iso-female line. Oral delivery of ds-CYP324F1 and ds-CYP306A1 directed against CYP324F1 and CYP306A1 to the larvae of one of the insecticide resistance populations caused reduced expression of these two transcripts in a dose dependent manner (53.4 to 85.0 %). It appears that the increased titer of O-demethylase is the result of increased transcription level of CYP genes in resistant populations. The data provides insight for identifying the novel resistance management strategies against L. orbonalis. This article is protected by copyright. All rights reserved.

The occurrence of fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) in maize fields of Tirupati region, Andhra Pradesh is herewith reported. Field surveys in maize fields revealed that the rove beetle, Paederus fuscipes Curtis (Coleoptera: Staphylinidae) was found predating the larvae of fall armyworm and this is the first report of P. fuscipes on fall armyworm from India. The species identity of both fall armyworm and the rove beetle was confirmed through molecular studies by amplifying cytochrome oxidase I gene (CO1) and DNA barcoding.

For the first time, the tachinid fly, Exorista xanthaspis (Wiedemann, 1830) (Diptera: Tachinidae), was found to parasitize the larvae of fall armyworm, Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) collected from maize fields in Karnataka, India. The field survey conducted during 2018-19 revealed the occurrence of E. xanthaspis on the larvae of S. frugiperda with the parasitism rate of 1.85 to 4.55% in maize fields. The identity of tachinid parasitoid was confirmed by amplifying Cytochrome Oxidase I gene (CO1-658 bp) and DNA.

Background: Blackgram is being cultivated as an indispensable pulse crop and a rich source of vitamins and minerals. Though the requirement for blackgram is high, the productivity is low. The ultimate aim of any plant breeder in a crop improvement program is to increase seed yield/ productivity. With this background, the current study was focused to investigate genetic variability/effects on important yield and its contributing traits of blackgram. Methods: The research material comprised of P1, P2, F1, F2 and F3 obtained from a cross between CO 6 and LBG 17 varieties in blackgram. Observations on nine biometrical traits were recorded from all these five populations for generation mean analysis. By employing Mather and Jinks (1971) scaling test of C and D, the suitability nature of the simple additive-dominance model can be identified. Following Hayman (1958) perfect fit solution, the mean of five generations (P1, P2, F1, F2 and F3) was utilized to calculate five parameters. Result: Fitted genetic model revealed as important yield and yield contributing traits governed by dominance and epistasis in this study, it indicates the selection may be postponed to later generations with greater homozygosity.

The eggplant shoot and fruit borer, Leucinodes orbonalis Guenee (Lepidoptera: Crambidae) is a monophagous and destructive insect pest of eggplant. L. orbonalis developed multiple insecticide resistance that led to frequent field control failures in many countries. The possible reversal of resistance in L. orbonalis requires an understanding of the expression dynamics of individual genes conferring resistance to insecticides through gene expression analysis. The availability of reference genes (RG) to normalize transcript data of target genes, achieved by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR), is mandatory. Hence, the present study investigated the stable expression pattern of nine putative reference genes viz., actin, 28S ribosomal protein S18c, mitochondrial isoform X2 (28SM), calnexin, β-tubulin, 28S ribosomal protein S3 mitochondrial (28SR3), TATA box binding protein (TATA), elongation factor-1α (EF-1α), glyceraldehyde-3-phosphate-dehydrogenase (GAPDH), and ubiquitin 60S ribosomal protein (Ubiquitin) to select the most stable genes that could be used as reference genes for target transcript gene normalization. Different algorithms such as ΔCt, geNorm, NormFinder and BestKeeper were used to assess gene expression stability. By integrating these data into online RefFinder tool, 28SR3 and GAPDH, were chosen as highly suitable RGs based on their stable expression pattern.

Microplitis maculipennis Szepligeti is an important parasitoid of castor semilooper Acanthodelta janata (L.) (Lepidoptera), a major pest of castor ( Ricinus communis L.). Microplitis Forster shares remarkable morphological resemblance with moderately diverse genus Snellenius Westwood. In this study, molecular characterization of M. maculipennis was done using Cytochrome Oxidase I (COI) to confirm its generic placement in the respective genus. The Bayesian Inference (BI) and Maximum Likelihood (ML) phylogenetic analysis performed with a total of 354 published BOLD database sequences (after pre-processing of a total of 2257 COI sequences) of Microplitis and Snellenius species, representing 129 named species and 226 species determined only to genus raises doubts on the retention of both these genera separately. Our studies reveal that COI gene could not discriminate Microplitis and Snellenius species clearly.

Blackgram, an important pulse crop of India and other Asian countries, is a rich source of protein. Genetic improvement in this crop is generally slow-paced due to the lack of wide genetic variability available for selection. To create variability for important morphological traits and yield, induced mutagenesis was attempted in a popular blackgram cultivar CO 6 using gamma rays (γ rays

Fall Armyworm (FAW), Spodoptera frugiperda, is a polyphagous pest capable of feeding over 80 plant species and was indigenous to the Western Hemisphere. Within a span of 4 years, FAW has established itself throughout most of the regions in Africa and Asia causing significant losses in maize production. Owing to its revamped distribution range, it would be prudent to analyze the ensuing genetic changes and study the emerging phylogeographic patterns across the world. In this regard, we would like to provide a current snapshot of genetic diversity of FAW in India 2 years after the initial introduction and compare it with the worldwide diversity in order to trace the origins and evolutionary trajectories of FAW in India. We have investigated around 190 FAW samples from different regions in India for strain identity and polymorphism analysis on the basis of partial mitochondrial cytochrome oxidase I (COI) gene sequences. Apart from the ancestral rice and corn strain haplotype, our study demonstrates the presence of 14 more haplotypes unique to India at a haplotype diversity of 0.356. We were also able to record inter-strain hybrid haplotypes of rice and corn strains in India. Regional heterogeneity within Indian populations seems to be quite low representative of extensive migration of FAW within India. Distribution analysis of pairwise differences and rejection of neutrality tests suggest that the FAW population in India might be undergoing expansion. Our data is consistent with the findings suggesting a recent and common origin for invasive FAW populations in Asia and Africa, and does not indicate multiple introductions to India. This study reports the highest genetic diversity for Indian FAW populations to date and will be useful to track the subsequent evolution of FAW in India. The findings would have important ramifications for FAW behavior and composition throughout the world.

The shoot and fruit borer,Leucinodes orbonalis(Lepidoptera: Crambidae) is the major cause of low productivity in eggplant and insecticides being the mainstay of management ofL. orbonalis. However, field control failures are widespread due to the evolution of insecticide resistance. Taking advantage of the whole genome sequence information, the present study investigated the level of insecticide resistance and the expression pattern of individual carboxylesterase (CE) and glutathione S-transferases (GSTs) genes in various field collected populations ofL. orbonalis. Dose-mortality bioassays revealed a very high level of resistance development against fenvalerate (48.2–160-fold), phosalone (94-534.6-fold), emamectin benzoate (7.2–55-fold), thiodicarb (9.64–22.7-fold), flubendiamide (187.4–303.0-fold), and chlorantraniliprole (1.6–8.6-fold) in field populations as compared to laboratory-reared susceptible iso-female colony (Lo-S). Over-production of detoxification enzymesviz., CE and GST were evident upon enzyme assays. Mining of the draft genome ofL. orbonalisyielded large number of genes potentially belonging to the CE and GST gene families with known history of insecticide resistance in other insects. Subsequent RT-qPCR studies on relative contribution of individual genes revealed over-expression of numerous GSTs and few CEs in field populations, indicating their possible involvement of metabolic enzymes in insecticide resistance. The genomic information will facilitate the development of novel resistance management strategies against this pest.

Occurrence of Spodoptera frugiperda (J. E. Smith) (Insecta: Lepidoptera: Noctuidae), commonly known as fall armyworm, in southern India is reported along with associated natural enemies. Severe damage was noticed in Chikkaballapur, Hassan, Shivamogga, Davanagere and Chitradurga during July-August 2018. The incidence ranged from 9.0 to 62.5 percent at various locations, maximum incidence was recorded in Hassan district followed by Chikkaballapur, Davanagere, Shivamogga and Chitradurga. Morphology and molecular based taxonomic tools were used for the identification of this pest. The GenBank accession number MH704433 of Chikkaballapur population was released on 1 st August, 2018 and Barcode obtained from BOLD System-ID: AGIMP054-18. The survey also revealed natural parasitism by egg parasitoids viz., Telenomus sp. (Hymenoptera: Platygastridae) and Trichogramma sp. (Hymenoptera: Trichogrammatidae), gregarious larval parasitoid, Glyptapanteles creatonoti (Viereck) (Hymenoptera: Braconidae) solitary larval parasitoid, Campoletis chlorideae Uchida (Hymenoptera: Ichneumonidae), and a solitary indeterminate larval-pupal (Hymenoptera: Ichneumonidae: Ichneumoninae) parasitoid. Spodoptera frugiperda is the first host record for G. creatonoti across the globe. Glyptapanteles creatonoti , being a well established parasitoid of various noctuids in India and Malaysia, was capable of parasitizing S. frugiperda . Besides these, other commonly found bioagents viz., Forficula sp. (Dermaptera: Forficulidae) and entomopathogenic fungus Nomuraea rileyi (Farl.) Samson was also collected in large numbers. We report the natural enemy complex of S. frugiperda for the first time from India. The electro physiological response of Indian population of S. frugiperda male adults to pheromone was established. The studies to manage this pest by any/all means are in progress.

Specimens of the aphid hunting wasp Carinostigmus Tsuneki (Hymenoptera: Crabronidae: Pemphredoninae) were collected from South India. Morphological identification revealed three species, and one of them, C. griphus Krombein, is new for India. Identification of the species is supported through COI partial gene-DNA barcoding.

In the present study, a total of eight species of aquatic and semi-aquatic Hemiptera collected from India were identified based on morphology and mitochondrial cytochrome oxidase gene I (COI). Details of morphology based identification and the utility of COI gene to identify the aquatic Hemiptera is discussed in this paper.

The toxic effect of commonly used insecticides in cotton fields was studied on 9 populations of Chrysoperla zastrowi sillemi (Esben-Petersen), an important predator of sucking pests collected in India. The dose mortality bioassay against 3-days old larvae was determined using three insecticides viz., endosulfan, fenvalerate and acephate by topical bioassay method. Mechanism of resistance to the above mentioned insecticides were determined without and with three metabolic inhibitors (synergists), viz ., piperonyl butoxide (PBO), S,S,S-tributyl-phosphorotrithioate (DEF) and diethyl maleate (DEM). Among the populations, resistant ratios (RR) of CZS-8 was significantly higher i.e. 50.36., 66.11 and 277.51-fold for endosulfan, fenvalerate and acephate, respectively compared to susceptible population (CZS-10). The CZS-8 was selected for synergism study it showed higher LC50 values and resistance ratio for all three insecticides. It showed 8.97-fold, 18.49-fold and 6.38-fold increase in synergism ratio for endosulfan indicating the resistance was strongly synergised by PBO, DEF and DEM. Similarly for fenvalerate, CZS-8 showed 8.69-fold and 3.63-fold significant increase in synergism ratio by DEF and DEM, respectively and for acephate, CZS-8 showed 54.82-fold, 150.87-fold and 113.52-fold significant increase in synergism ratio indicating that the resistance could be due to cytochrome p-450, esterase and glutathione s- transferase activity. The study indicated that the field population of C. z. sillemi developed resistance to different groups of insecticides. Among different geographical populations, CZS-8 collected from Sriganganagar, was recorded as most resistant.

New challenges appear with every biological invasion and presses need to probe their ecological interactions. In the comprehensive yet complicated food web associated with the niche of the recently invaded cassava mealybug (CMB) Phenacoccus manihoti Matile-Ferrero (Hemiptera: Pseudococcidae), there was a multitrophic interaction structured vertically as well as horizontally. Altogether 45 species: thirty four species of insects from six orders (Coleoptera, Diptera, Hemiptera, Hymenoptera, Lepidoptera, and Neuroptera) and eleven species of spiders (Araneae) were grouped under four trophic levels into 11 guilds. The analysis of trophic guild structure and interaction indicated that many indigenous parasitoid species, which qualified to be placed under the fourth trophic level, actively parasitized the potential native predators of cassava mealybug (CMB) and thereby negatively impacted the natural biological control of CMB. Most of these resident hyperparasitoid species were recorded for the first time, to be associated directly or indirectly with CMB. The species diversity at fourth trophic level could be viewed as a bioindicator and one of the most important determinant factors on the success rate of any biological control program. No indigenous primary parasitoids were documented on CMB from any of the sites sampled. In the absence of any indigenous parasitoids and high level of parasitization of the potential CMB predators, the long-term and indirect ecosystem risks will be significant until the introduction and establishment of the proven classical biological control agent, Anagyrus lopezi (De Santis) (Encyrtidae: Hymenoptera) from other countries.