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Spodoptera exigua (Hubner, 1808) (Lepidoptera: Noctuidae) is a significant agricultural crop pest in Indonesia, causing significant economic losses in recent years. This species' ability to survive on a wide variety of host plants provides an adaptive advantage for survival in the environment, which is facilitated by its high mobility, fecundity, and capability to acquire resistance to a broad spectrum of chemical pesticides. It is well-established that knowledge of diversity and evolutionary origins facilitate the development of disease management strategies. In the present study, we report the morphology, diversity and phylogeny analysis of S. exigua from North Sulawesi, Indonesia. The specimen from Rurukan have a body size and other segments that are longer than in Langowan and Modoinding. Dendrogram analysis shows that the similarity distance based on morphology ranges from 1-25%, which forms four clusters, where the specimen from Rurukan is separated from the rest of the specimens. The phylogeny of S. exigua from North Sulawesi, Indonesia, based on CO1 (Cytochrome c oxidase subunit 1) gene fragment, which is juxtaposed with CO1 data of the allied species from many geographical locations. A total of twenty-five isolates representing Indonesia, Japan, Germany, Thailand, India, UK, USA, Spain and Australia were compared. Nineteen sequences of S. exigua retrieved from GenBank were selected as references based on previous published phylogenic trees. The twenty-four isolates were scattered in two distinct clades indicating S. exigua is polyphyletic, but S. exigua from North Sulawesi, Indonesia is monophyletic. [ J Adv Biotechnol Exp Ther 2022; 5(1.000): 136-147]

Baculoviruses constitute a large group of invertebrate DNA viruses, predominantly infecting larvae of the insect order Lepidoptera. During a baculovirus infection, the virus spreads throughout the insect body producing a systemic infection in multiple larval tissues, included the central nervous system (CNS). As a main component of the CNS, neuropeptides are small protein-like molecules functioning as neurohormones, neurotransmitters, or neuromodulators. These peptides are involved in regulating animal physiology and behavior and could be altered after baculovirus infection. In this study, we have investigated the effect of Spodoptera exigua multiple nucleopolyhedrovirus (SeMNPV) infection on expression of Spodoptera exigua neuropeptides and neuropeptide-like genes. Expression of the gene encoding a polypeptide that resembles the well-known insect neuropeptide proctolin and named as proctolin-like peptide (PLP), was downregulated in the larval brain following infection and was chosen for further analysis. A recombinant Autographa californica multiple nucleopolyhedrovirus (AcMNPV) overexpressing the C-terminal part of the PLP was generated and used in bioassays using S. exigua larvae to study its influence on the viral infection and insect behavior. AcMNPV-PLP-infected larvae showed less locomotion activity and a reduction in growth compared to larvae infected with wild type AcMNPV or mock-infected larvae. These results are indicative of this new peptide as a neuromodulator that regulates visceral and skeletal muscle contractions and offers a novel effector involved in the behavioral changes during baculovirus infection.

The beet army worm, Spodoptera exigua, is a widely distributed polyphagous pest of economically important crops worldwide.\ud The management of this pest insect continues to face many challenges. Despite synthetic chemicals posing a serious\ud threat to the environment, these remain the conventional approach for controlling S. exigua in the field. An over-reliance on\ud chemical control has not only led to selection for resistance to insecticides and to a reduction of natural enemies, but has also\ud polluted various components of ecosystem. Given these increasing pressures on the ecosystem, there is a need to implement\ud integrated pest management (IPM) approaches exploiting a wider range of tools (biotechnological approaches, microbial\ud control, biological control, cultural control, and use of host plant resistance) for an alternative to chemical control. The IPM\ud approach can not only reduce the hazard of chemical residues in the environment and associated health problems, but may\ud also provide best strategies to control insect pests. This review synthesizes published information on insecticide resistance\ud of S. exigua and explores alternative IPM approaches to control S. exigua.

Migration is a widespread phenomenon among many insect species, including herbivorous crop pests. At present, scant information exists on the long-range migration of the polyphagous armyworm, Spodoptera exigua and its underlying climatic determinants (i.e. East Asian or South Asian monsoon circulation). In this study, we employed a population genetics approach to delineate S. exigua migration patterns across multiple Asian countries.Using mitochondrial cytochrome I (COI) and microsatellite markers, low-to-moderate levels of genetic diversity were detected among 101 S. exigua populations collected across China, Pakistan and Vietnam. Haplotype diversity and nucleotide diversity did not differ between years. Two spatially explicit genetic clusters were detected, an eastern and a western clade, with the former comprising populations in the East Asia monsoon area. No genetic differentiation was recorded among armyworm populations in the year-round breeding area, nor among those of the overwintering and nonoverwintering areas. Five of the most widespread mitochondrial haplotypes reflected the extensive gene flow across at a large spatial scale.Low-to-moderate levels of genetic diversity were observed, and evidence was found for genetic clustering in certain geographical areas. Accordingly, our unique insights into S. exigua population genetics and spatiotemporal migration dynamics help to guide applied ecological studies, ecological intensification schemes or (area-wide) pest management campaigns in China and abroad. © 2021 Society of Chemical Industry.

The impact of root infection by the nematode Meloidogyne incognita on leaf anti-herbivore defenses and plant resistance to the caterpillar Spodoptera exigua is modulated by the nematode infection cycle., Studies on plant-mediated interactions between root parasitic nematodes and aboveground herbivores are rapidly increasing. However, outcomes for the interacting organisms vary, and the mechanisms involved remain ambiguous. We hypothesized that the impact of root infection by the root-knot nematode Meloidogyne incognita on the performance of the aboveground caterpillar Spodoptera exigua is modulated by the nematode’s infection cycle. We challenged root-knot nematode-infected tomato plants with caterpillars when the nematode’s infection cycle was at the invasion, galling, and reproduction stages. We found that M. incognita root infection enhanced S. exigua performance during the galling stage, while it did not affect the caterpillar’s performance at the invasion and reproduction stages. Molecular and chemical analyses performed at the different stages of the nematode infection cycle revealed that M. incognita root infection systemically affected the jasmonic acid-, salicylic acid-, and abscisic acid-related responses, as well as the changes in the leaf metabolome triggered during S. exigua feeding. The M. incognita-induced leaf responses varied over the nematode’s root infection cycle. These findings suggest that specific leaf responses triggered systemically by the nematode at its different life-cycle stages underlie the differential impact of M. incognita on plant resistance against the caterpillar S. exigua.

Temporal dynamics of Helicoverpa armigera and Spodoptera exigua in relation to weather factors was studied using pheromone trap catches during 2017–18 and 2018–19 at ICAR- IARI, New Delhi. Results indicated the presence of both the pest adults throughout the year with fluctuations. Male moths catches were 714 and 855 for H. armigera during 2017–18 and 2018–19, respectively, the corresponding values for S. exigua were 658 and 324. More H. armigera male moths were captured during 9th–19th standard meteorological week (SMW) and 8th–23rd SMW with peaks during 15th and 17th SMW in 2017–18 and 2018–19, respectively. In case of S. exigua, highest adult activity was observed during 9–20th SMW with peak activity during 15th SMW in 2017–18, while in 2018–19, it occurred during 49th SMW. Correlation analysis revealed that male moth population of both the pests had significant positive relationship with maximum temperature and sunshine hours, while they had significant negative association with relative humidity.

Shallots are one of the important commodities of high economic value in Indonesia. One of the obstacles in the production of shallots is the attack of pests and pathogens. The potential for yield loss due to pest and pathogen attacks can reach 20-100%. The research was carried out in the villages of Tegalarum, Sukorukun, and Sumberarum, Jaken District, Pati Regency from January to February 2021. The research used field observation methods, using swing nets to collect pests. This study aims to determine the types and diversity of pests in shallots cultivation in Jaken District, Pati Regency. The results of the research in the shallot plantations of Tegalarum and Sukorukun Villages found 3 species of pests, namely Liriomyza chinensis, Spodoptera exigua, and Bemisia tabaci. Meanwhile, in Sumberarum Village, 4 species of pests were found, namely Liriomyza chinensis, Spodoptera exigua, Bemisia tabaci, and Spodoptera litura. The diversity index (H') for Tegalarum and Sukorukun villages was low while Sumberarum villages were moderate. The evenness index (E) in the 3 villages is fairly evenly, while the species richness index (R) and dominance (D) for the three villages are low.

Впервые описано присутствие участков гомологии в геномах восточной прыткой ящерицы к длинным концевым повторам эндогенных ретровирусов Sabrina и SIRE-1 и выполнен сравнительный анализ спектров продуктов амплификации фрагментов геномной ДНК ящерицы Lacerta agilis exigua, полученных с использованием двух типов ДНК маркеров - фрагментов геномной ДНК, ящериц, фланкированных инвертированными повторами микросателлитных локусов и длинными концевыми повторами эндогенных ретровирусов The presence of homology regions in the long terminal repeats of the endogenous retroviruses Sabrina and SIRE - 1 in the genomes of the eastern sand lizard was described for the first time. A comparative analysis of the spectra of amplification products of genomic DNA fragments of the mentioned lizard species obtained using two types of DNA markers - fragments of genomic DNA, flanked by inverted repeats of microsatellite loci and long terminal repeats of endogenous retroviruses, was performed.

Marine natural products play critical roles in the chemical defense of many marine organisms and are essential, reputable sources of successful drug leads. Sixty-seven 14-membered resorcylic acid lactone derivatives 3–27 and 30–71 of the natural product zeaenol (1) isolated from the marine-derived fungus Cochliobolus lunatus were semisynthesized by chlorination, acylation, esterification, and acetalization in one to three steps. The structures of these new derivatives were established by HRESIMS and NMR techniques. All the compounds (1–71) were evaluated for their antialgal and antiplasmodial activities. Among them, 14 compounds displayed antifouling activities against adhesion of the fouling diatoms. In particular, 9 and 34 exhibited strong and selective inhibitory effects against the diatoms Navicula laevissima and Navicula exigua (EC50 = 6.67 and 8.55 μmol/L), respectively, which were similar in efficacy to those of the positive control SeaNine 211 (EC50 = 2.90 and 9.74 μmol/L). More importantly, 38, 39, and 69–71 showed potent antiplasmodial activities against Plasmodium falciparum with IC50 values ranging from 3.54 to 9.72 μmol/L. Very interestingly, the five antiplasmodial derivatives displayed non-toxicity in the cytotoxicity assays and the zebrafish embryos model, thus, representing potential promising antiplasmodial drug agents. The preliminary structure–activity relationships indicated that biphenyl substituent at C-2, acetonide at positions C-5′ and C-6′, and tri- or tetra-substituted of acyl groups increased the antiplasmodial activity. Therefore, combining evaluation of chemical ecology with pharmacological models will be implemented as a systematic strategy, not only for environmentally friendly antifoulants but also for structurally novel drugs.

Fungal pathogens cause significant losses both in terms of quality and quantity on oregano (Origanum spp.) cultivation. Various fungal diseases on oregano grown in experimental plots of Ankara Field Crops Research Institute were observed in the years 2018–2020. A lot of symptoms; including dark brown necrosis, brown discoloration in the xylem vessels, brown spots and necrosis on the stems, splitting on the stem and branches together with brown, leaf spots and blights at varying sizes were observed. In addition, brown rust symptoms were also found. The fungal pathogens were isolated by plating disease samples taken from the peripheries of the necrosis or spots on culture media of water agar, potato dextrose agar and malt extract agar. The obtained fungi were identified by their morphological characteristics first, at least at genus rank and then by generating ITS1 and ITS4 gene sequences and comparing the sequences by the ones deposited in GeneBank. The most common and widespread pathogen was Boeremia exgua var. exigua and it was isolated from disease symptoms on branches, stems, collars and leaves from all the Oregano genotypes. From the brown necrotic areas at the collar, mostly Fusarium equiseti was isolated. From the leaf spots, along with Boeremia exgua var. exigua, Alternaria alternata complex and A. tenuissima were also recovered. The rust pathogen Puccinia menthae was determined on only Origanum vulgare var. gracile. Alternaria alternata complex, A. tenuissima, Fusarium equiseti, Boeremia exgua var. exigua were first records on Origanum spp. and Puccinia menthae on Origanum vulgare var. gracile in Turkey.

We have constructed two intra-molecularly shuffled promoters, namely S100 and D100. The S100 recombinant promoter (621 bp) was generated by ligation of 250 bp long upstream activation sequence (UAS) of Strawberry vein banding virus (SV10UAS; − 352 to − 102 relative to TSS) with its 371 bp long TATA containing core promoter domain (SV10CP; − 352 to + 19). Likewise, 726 bp long D100 promoter was constructed by fusion of 170 bp long UAS of Dahlia mosaic virus (DaMV14UAS; − 203 to − 33) with its 556 bp long core promoter domain (DaMV4CP; − 474 to + 82). S100 and D100 promoters showed 1.8 and 2.2 times stronger activities than that of the CaMV35S promoter. The activity of the promoters is comparable to that of the CaMV35S2 promoter. Transcript analysis employing qRT-PCR and histochemical assays supported the above findings. Abscisic acid and salicylic acid induce the activity of the D100 promoter. Leaf protein obtained from Nicotiana tabacum plant expressing NSD2 gene (Nigella sativa L. defensin 2) driven by the D100 promoter showed antifungal activity against Alternaria alternata and Phoma exigua var. exigua and antibacterial activity against Pseudomonas aeruginosa and Staphylococcus aureus. Strong S100 and D100 promoters have potential to become efficient candidates for plant metabolic engineering and molecular pharming.

Beet a rmyworm (Spodoptera exigua H ubner) is one of the main problems in shallot cultivation which can cause production losses of up to 100% if not controlled. The use of botanical pesticides from jengkol rind extract (Pithecellobium lobatum Benth) is a solution to control beet armyworm s (Spodoptera exigua Hubner). This study aims to obtain a concentration of jengkol rind extract which is effective to controlling beet armyworm. The study was conducted at the Laboratory of Plant Pest and Experimental Garden at the Faculty of Agriculture, University of Riau from January until March 2020. This research was conducted experimentally using a completely randomized design (CRD) with five treatments and four replications. The treatments given were jengkol rind extract concentration 0 g.l -1 water, 25 g.l -1 water, 50 g.l -1 water, 75 g.l -1 water and 100 g.l -1 water. The results indicate that the application of jengkol rind extract 100 gl -1 water is an effective concentration to control beet armyworm with an initial time of death 12.75 hours, a lethal time 50 at 37.50 hours, the highest daily mortality on the second day at 37.5% and total mortality is 92.5% in the 5 days after application .

NPVThe beet armyworm, Spodoptera exigua, is a serious insect pest infesting various vegetable crops. Two infectious insect viruses, baculovirus and iflavirus, are known to induce epizootics in S. exigua populations. Indeed, some laboratory colonies have appeared to be covertly infected by these viruses. Diagnostic PCR tests detected two different viruses: Spodoptera exigua multiple nucleopolyhedrosis virus (SeMNPV) and iflaviruses (SeIfV1 and SeIfV2). Viral extract from dead larvae of S. exigua could infect Sf9 cells and produce occlusion bodies (OBs). Feeding OBs to asymptomatic larvae of S. exigua caused significant viral disease. Interestingly, both SeIfV1 and SeIfV2 increased their titers at late larval stages. Sterilization of laid eggs with 1% sodium hypochloride significantly reduced SeMNPV titers and increased larval survival rate. Doublestranded RNA (dsRNA) specific to SeIfV1 or SeIfV2 significantly reduced viral titers and increased larval survival rate. To continuously feed dsRNA, a recombinant Escherichia coli HT115 expressing SeIfV1-dsRNA was constructed with an L4440 expression vector. Adding this recombinant E. coli to the artificial diet significantly reduced the SeIfV1 titer and increased larval survival. These results indicate that laboratory colony collapse of S. exigua is induced by multiple viral infections. In addition, either suppression of SeMNPV or SeIfV infection significantly increased larval survival, suggesting a cooperative pathogenicity between baculovirus and iflavirus against S. exigua.

A new genus, Anicula gen. n. (Gelechiidae) with the type species A. tristificula sp. n., and four new species of the genus Gelechia Hubner (G. festa sp. n., G. exigua sp. n., G. pallidula sp. n., and G. gilva sp. n.) are described from central and southern Laos and eastern Malaysia.

Serine protease inhibitors (serpins) are a broadly distributed protease superfamily in various organisms, which participate in the negative regulation of melanization in insects. Our pervious study demonstrated that induced melanization by Heliothis virescens ascovirus 3h is helpful for HvAV-3h viral replication. In this study, the serpin-2.1 like gene from Spodoptera exigua (Seserpin-2.1 like) which is a specific serpin after HvAV-3h infection was identified. Seserpin-2.1 like has the typical characteristics of serpin proteins family. Seserpin-2.1 like widely distributed in various tissues (including hemolymph, fat body, midgut, cuticle and head), and expressed at a higher level in fat body, hemolymph and head. At different developmental stages, it tends to express at eggs and 5th instar larvae. Seserpin-2.1 like shows special phenomenon for HvAV-3h infection. On the one hand, the transcription level of Seserpin-2.1 like in hemolymph was significantly upregulated after HvAV-3h compared to other immune challenges Gram-positive bacteria (Bacillus thuringiensis), Gram-negative bacteria (Escherichia coli), and Baculovirus (Autographa californica nucleopolyhedrovirus). On the other hand, its expression disappeared during 72 to 120 h post infection. In summary, our results suggest that Seserpin-2.1 like may be involved in innate immunity of S. exigua after infection with HvAV-3h. And HvAV-3h may inhibit the expression of Seserpin-2.1 like to promote the melanization of host larvae for viral replication.

The dried twigs of Piper ribesioides were used to prepare various extracts in different solvents. Each extract was evaluated for their toxicity against 2nd instar larvae of Spodoptera exigua. The highest acute toxicity was observed for ethyl acetate extract with an LD50 of 3.25 and 2.50 μg/larva and LD90 of 9.19 and 8.15 μg/larva after 24 and 48 h post-treatment after topical application. Piperine, methyl piperate, N-cinnamoyl-(2-phenylethyl) amine, pinostrobin, pinocembrin, cinnamic acid, lemairamin, N,N-Diphenylcinnamide, and methyl cinnamate were isolated from this extract that was toxic to S. exigua larvae. Cinnamic acid was the most active compound with a LD50 of 0.17 μg/larva after 48 h of topical treatment. Piperine was significantly similar in activity (LD50 = 0.19 μg/larva), but toxicity decreased with the change in structural configuration as observed with methyl piperate (LD50 = 0.73 μg/larva). Other compounds were 3 to 11-fold less toxic than cinnamic acid and piperine. Growth of survived S. exigua larvae until adult emergence after topical application was recorded and maximum inhibition of about 70% was observed after the application of cinnamic acid. Egg hatch was only 29.11% after cinnamic acid treatment, compared to 97.38% in controls. Neither induction nor inhibition of detoxification enzymes due to treatment of extracts were statistically significant, however, individual compounds like cinnamic acid, methyl cinnamate, piperine, pinostrobin, pinocembrin, and lemairamin did show a moderate impact on these enzymes.

Background: Vip3Aa is a vegetative insecticidal protein produced by Bacillus thuringiensis. The protein is produced as an 88-kDa protoxin that could be processed by insect gut proteases into a 22-kDa N-terminal and a 66-kDa C-terminal fragments. The C-terminal part could bind to a specific receptor while the N-terminal part is required for toxicity and structural stability. Objective: To demonstrate the antagonistic effect of truncated fragments on the insecticidal activity of the full-length Vip3Aa. Methods: The full-length protein (Vip3Aa), a 66-kDa C-terminal fragment (Vip3Aa-D199) and a predicted carbohydrate binding module (CBM) were produced in Escherichia coli. Purified proteins were mixed at different ratios and fed to Spodoptera litura and Spodoptera exigua larvae. Mortality was recorded and compared between larvae fed with individual toxin and mixtures of the full-length and truncated toxins. Results: Production level of the Vip3Aa-D199 was significantly decreased comparing to that of the full-length protein. Vip3Aa-D199 and CBM fragment were not toxic to insect larvae whereas Vip3Aa showed high toxicity with LC50 about 200 ng/cm2. Feeding the larvae with mixtures of the Vip3Aa and Vip3Aa-D199 at different ratios revealed antagonistic effect of the Vip3Aa-D199 on the toxicity of Vip3Aa. Results showed that the lethal time (LT 50 and LT 95) of larvae fed the mixture toxins was longer than those fed the Vip3Aa alone. In addition, a CBM fragment could inhibit toxicity of the full-length Vip3Aa. Conclusion: Our results demonstrated that the Vip3Aa-D199 and a CBM fragment could complete for the membrane binding thus rendering activity of the full-length Vip3Aa.

The cultivars of most Brazilian Arabica coffee plantations are susceptible to root knot nematodes (RKN), Meloidogyne spp. By planting resistant rootstocks of the species Coffea canephora, a successful strategy in some producing regions, coffee can be cultivated in RKN-infested areas. However, the only currently available rootstock cultivar in Brazil has a segregation rate close to 20% for susceptibility. To breed new rootstock cultivars resistant to the main RKN species, with a lower segregation rate, 10 C. canephora clones were selected in areas infested by these nematodes, with confirmed resistance to Meloidogyne exigua, M. incognita and M. paranaensis, under controlled conditions. The genetic compatibility analysis of the clones detected only one incompatible combination (CcK1xCcR5 and its reciprocal). Almost all F1 hybrids resulting from the cross between the selected clones were resistant to M. exigua and M. incognita. According to the reproduction factor, 77% of the evaluated F1 hybrids proved resistant to M. paranaensis, and those classified as susceptible had variable segregation rates within the progeny, generally lower than 25%. Based on these data, different hybrid combinations can be suggested for the development of new rootstock cultivars of C. canephora with simultaneous resistance to coffee RKN. This approach has immediate practical applications in grafting Arabica coffee scion cultivars in areas where nematodes restrict cultivation.

Bioinsecticides based on Bacillus thuringiensis toxins can be a safe alternative to chemical pesticides currently used to control Spodoptera exigua (Hubner; Lepidoptera: Noctuidae)–a worldwide, polyphagous pest species. However, only a few B. thuringiensis proteins have been proven effective against S. exigua and currently used B. thuringiensis bioinsecticides are not efficient in control of this pest–therefore, new biocontrol approaches are needed. Some research suggest that synergistic interactions can occur between certain Bt toxins and increase their insecticidal activity. Multiple-toxin bioinsecticides are also recommended to prevent field-evolved resistance. In this study, the insecticidal efficacy of five selected B. thuringiensis proteins (Cry1Aa, Cry1Ca, Cry1Ia, Cry2Ab and Vip3Aa) has been assessed, together with eight mixtures containing two or three of these toxins. The composition containing Cry1Ca and Vip3Aa is the most active against S. exigua , followed by: Cry1Aa + Vip3Aa; Cry2Ab + Vip3Aa; Cry1Aa + Cry2Ab + Vip3Aa; Cry1Aa + Cry1Ca; Cry1Ca + Cry2Ab and Cry1Aa + Cry1Ca + Cry2Ab. The results gathered at 7 days after treatment (DAT) indicate synergistic interactions between most of these mixtures. Interestingly, the results obtained at 10 DAT suggest synergism only in three combinations (Cry1Ca + Vip3Aa, Cry1Aa + Vip3Aa, Cry1Aa + Cry1Ca). Moreover, the estimated synergism factors are 1.6-2.2-fold lower than at 7 DAT. The only exception is the Cry1Ca + Vip3Aa composition, for which high synergism factor (>4) was calculated at both scoring times. This work shows that the time of data record can substantially influence the interaction type estimation. The most potent compositions should be used to develop new bioinsecticides (transgenic crops or targeted recombinant strains) with high effectiveness against S. exigua .

Gastrulation is a fundamental morphogenetic process in development. In echinoderms with ancestral-type development through feeding larvae, gastrulation involves radially symmetrical invagination of cells around the blastopore. Gastrulation in the seastar Parvulastra exigua, a species with non-feeding larvae deviates from this pattern. Microinjection of cells with fluorescent lineage tracer dye revealed that early blastomeres contribute unequally to ectoderm and endoderm. In embryos injected at the two-cell stage, asymmetry was evident in the fluorescence at the top of the archenteron and animal pole ectoderm. Archenteron elongation is driven by asymmetrical involution of cells with more cells crossing the blastopore on one side. Lineages of cells injected at the four-cell stage also differed in allocation to endoderm and ectoderm. In embryos injected at the eight-cell stage ectodermal and endodermal fates were evident reflecting the animal and vegetal fates determined by third cleavage as typical of echinoderms. Modification of gastrulation associated with evolution of development in P. exigua shows that this foundational morphogenetic process can be altered despite its importance for subsequent development. However, observations of slight asymmetry in the lineage fates of blastomeres in asterinids with planktotrophic development indicates that gastrulation by asymmetrical involution in P. exigua may be a hypertrophic elaboration of a pre-existing state in ancestral-type development. As for echinoids with lecithotrophic development, involution as a mechanism to contribute to archenteron elongation may be associated with the impact of extensive maternal nutritive reserves on the mechanics of cell movement and a novel innovation to facilitate early development of the adult rudiment.

Plants that can be used as pesticides are Gadung tubers. Gadung tubers contain cyanide acid to kill armyworm pests because they contain dioscorin toxins which can cause nervous disorders. The purpose of this study was to determine the effect of Gadung tuber extract (Dioscorea hispida) on Caterpillar mortality (Spodoptera exigua) in Shallot plants. This type of research is experimental research. This study used a completely randomized design (CRD). The sample used was 5 caterpillars (Spodoptera exigua) in each polybag with 5 repetitions for each concentration of Gadung tuber extract, namely 0%, 0.5%, 1.0%, 1.5%, 2.0% and 2.5%, so the total Caterpillar used was 150 Caterpillars. Gadung tuber extraction was carried out by maceration method with methanol solvent. Data were analyzed using a one-way analysis of variance at the 95% significance level, followed by DMRT (Duncans Multiple Range Test). The results showed that the Gadung tuber extract had a significant effect on the mortality of caterpillars (Spodoptera exigua) because the F count was greater than the F table (45.40>2.62), and the DMRT test results showed that the optimal concentration of Gadung tuber extract was 2.5%. Therefore, it can be concluded that the extract of Gadung tuber (Dioscorea hispida) affects the mortality of Caterpillars (Spodoptera exigua) in Shallots (Allium cepa).

The beet armyworm Spodoptera exigua (Hübner) is a serious polyphagous pest that infests vegetable crops worldwide and has rapidly developed resistance due to its long-term exposure to insecticides. The current resistance statuses to four insecticides exhibited by three field populations of beet armyworms collected in southern China from 2014 to 2018 were investigated. Monitoring data from five consecutive years demonstrated that all three tested S. exigua populations developed extremely high resistance to chlorantraniliprole in 2018 (220.58- to 2,597.39-fold). Two populations (Baiyun and Fengxian) developed low to moderate resistance to spinosad, whereas the Huangpi population remained susceptible (except in 2014, with RR of 6.11-fold). The RR of the Fengxian and Baiyun populations to indoxacarb steadily increased over the years, whereas that of the Huangpi population increased relatively slowly. The Baiyun and Fengxian populations developed moderate to high resistance to indoxacarb and methoxyfenozide, whereas the Huangpi population exhibited susceptibility to low resistance (1.06- to 6.45-fold) to indoxacarb and susceptibility to moderate resistance (1.53- to 14.22-fold) to methoxyfenozide. These results suggest that chlorantraniliprole should not be employed to control this pest in southern China. Reduced use of indoxacarb and methoxyfenozide or the use of alternating insecticides with low levels of resistance is recommended. Spinosad remains an effective insecticide for the management of S. exigua. To avoid the rapid development of insecticide resistance, rotations of insecticides with low levels of resistance and different modes of action based on the resistance patterns of S. exigua should be performed in southern China.

Recently, resistance to diamide insecticides has been reported in various lepidopteran pests, including Spodoptera exigua. Six field populations and a local population were tested, and results revealed high levels of diamide resistance. We selected a diamide-resistant strain, showing LC50 values 28,950- and 135,286-fold higher than those of a susceptible strain against chlorantraniliprole and flubendiamide, respectively. However, G4946E mutation in the ryanodine receptor, one of the well-known diamide resistance mechanisms, was not found in the tested resistant field populations. Instead, through genome sequencing, we found an I4790M mutation and some InDels, particularly a 29-bp insertion in the neighboring intron that was associated with this resistant allele. By using this distinct region, resistant allele diagnostic primers were designed and applied in a lamp loop-mediated isothermal amplification (LAMP) assay and general PCR. The applicable temperature of the LAMP assay was from 63 to 65 °C for 2 h with four primers. Addition of a loop primer further increased the amplification efficiency. LAMP was feasible with a broad range of DNA concentrations, with a minimum detectable concentration of 100 pg. A DNA releasing method comprising 5 min of incubation at 95 °C allowed DNA detection from some larva and adult samples. The combination of this DNA releasing technique and LAMP resulted in a rapid (up to 100 min) and accurate diagnostic strategy that could be applied to monitor and manage diamide resistance in S. exigua.

Lepidoptera is the second most diverse insect order outnumbered only by the Coeleptera. Acetylcholinesterase (AChE) is the major target site for insecticides. Extensive use of insecticides, to inhibit the function of this enzyme, have resulted in the development of insecticide resistance. Complete knowledge of the target proteins is very important to know the cause of resistance. Computational annotation of insect acetylcholinesterase can be helpful for the characterization of this important protein. Acetylcholinesterase of fourteen lepidopteran insect pest species was annotated by using different bioinformatics tools. AChE in all the species was hydrophilic and thermostable. All the species showed lower values for instability index except L. orbonalis, S. exigua and T. absoluta. Highest percentage of Arg, Asp, Asn, Gln and Cys were recorded in P. rapae. High percentage of Cys and Gln might be reason for insecticide resistance development in P. rapae. Phylogenetic analysis revealed the AChE in T. absoluta, L. orbonalis and S. exigua are closely related and emerged from same primary branch. Three functional motifs were predicted in eleven species while only two were found in L. orbonalis, S. exigua and T. absoluta. AChE in eleven species followed secretory pathway and have signal peptides. No signal peptides were predicted for S. exigua, L. orbonalis and T. absoluta and follow non secretory pathway. Arginine methylation and cysteine palmotylation was found in all species except S. exigua, L. orbonalis and T. absoluta. Glycosylphosphatidylinositol (GPI) anchor was predicted in only nine species.

Goal. To establish the spread of the latent form of the phomosis pathogen in the western region of the Forest-Steppe zone and to study the possibility of crop protection through the use of biofungicides. Methods. In the process of work used laboratory (cultivation of pathogens) and field (analysis, processing of tuber material). Results. The results of research conducted during 2019—2020 to detect latent infection of phomosis rot of potatoes in the western part of the forest-steppe zone of Ukraine (Zakarpattia, Chernivtsi, Ivano-Frankivsk regions) are presented. Within two years, the highest damage to tubers by latent phomosis infection was observed in varieties Yavir and Vodogray in the Ukrainian Carpathians (Ivano-Frankivsk region, Verkhovyna district, Bystrets village; Zakarpattia region, Mizhhirya district, Maidan village; Zakarpattia region, Rakhiv district, Yasinya village; Chernivtsi region, Vyzhnytskyi district, Berehomet village), which reached 25—33 and 21.0—23.0%, respectively. In the plain zone of Chernivtsi region (Hertsaiv district, Bukivka village; Novoselytsia district, UkrNDSKR IZR) a significantly lower percentage of tuber lesions with a latent form of the disease was observed. The minimum rates of tuber damage, both latent form of phomosis and with existing external signs, were observed in the variety Slovyanka and were in the plain zone 4.5—5.5% and 7.0—8.0 in the mountain. When treating tubers with biofungicides, the least pathogen tuber damage was observed in the variants using Trichodermin-Bio, PhytodoDoctor and Planriz, where the number of infected tubers was 10.0, 11.0 and 12.5%, respectively. In the control variant, the percentage of affected tubers with latent form of phomosis was 2.1—3.2 times higher than in the experimental ones. The effectiveness of biofungicides was greatest when using Trichodermin-Bio and PhytoDoctor and was 68.3 and 65.1%, respectively. Less effective drug against the latent form of phomosis, compared with other options was Hetomic, where its technical efficiency was 52.4%. Conclusions. The causative agent of phomotic rot of potatoes (Phoma exigua var. Exigua) in latent form is a widespread pathogen in the western part of the Forest-Steppe zone. To limit the spread of latent infection of phomos, biological drugs Hetomik (0.4 kg/ha) were used, Gaupbsin (5 l/t), Planriz (2 l/t), Trichodermin-Bio (2 l/t), PhytoDoctor (0.3 l/t), which helped to reduce the damage to the tubers by a latent form of the disease by 2.1—3.2 times compared to the control.

The research was carried out to determine the appropriate number of sex pheromone traps for monitoring the Spodoptera exigua moths in shallot crop which was grown in Yogyakarta Special Territory, Bantul Regency (Samas). This research was conducted in August until September 2016. Sex pheromone trap was arranged on shallot aged 3 weeks after planting. Sex pheromone trap with hexadecenat tetra asetat ingredients was placed on sticky yellow trap. This research used RCBD experimental design with single factor experiment namely the number of trap i.e. 3, 5, 6, 8 units/2.000 m2 with sex pheromone, and three traps without sex pheromone as control. Each treatment was repeated 5 times so 125 samples of experiments were obtained. Observation was made by counting the number of moths caught in sex pheromone trap. The result of observation was analysed with analysis of variance (ANOVA) and DMRT α 5.0%. The results show that the appropriate number of trap to monitor the pest infestation was 3 units/2.000 m2.

Background The cotton bollworm, Helicoverpa armigera (Hubner), and the beet armyworm, Spodoptera exigua (Hubner), are two major polyphagous lepidopteran pests of cultivated crops. They develop various levels of resistance to many frequently applied broad-spectrum insecticides. Here, the larval susceptibilities of a laboratory population and six field-collected populations per pest from Hunan Province, China to three insecticides were determined using a standard leaf-dipping method in the laboratory. Field-plot trials were conducted to verify the control efficacies of broflanilide 100 g L-1 suspension concentrate (SC), chlorantraniliprole 5% SC and emamectin benzoate 5.7% water-dispersible granule, against H. armigera and S. exigua larvae using foliar sprays in 2013 and 2019. Results Variations among H. armigera and S. exigua field populations in their susceptibility levels to the three insecticides were observed in Linli, Yueyang and Changsha counties from 2013 to 2019. They were still high susceptibility to broflanilide only, but developed low and/or moderate levels of resistance to chlorantraniliprole and emamectin benzoate. In addition, broflanilide at 25 g ha-1 provided an excellent control efficacy of 81.92% to 96.46% against these pests during the 3-14-days period after treatment in both years, whereas chlorantraniliprole at 50 g ha-1 and emamectin benzoate at 4.5 g ha-1 exhibited significantly decreased efficacies, which were consistent with their corresponding toxicity levels. Conclusions These results suggest that broflanilide should be an important new tool for the effective control of diamide- and avermectin-resistant H. armigera and S. exigua. © 2020 Society of Chemical Industry.

Some botanical extracts affect the cellular immune system of insects by interfering with normal hemocyte function. This gives rise to diminution in cellular immunity and causes a decrease in insect...

espanolBeauveria bassiana es un hongo entomopatogeno que produce metabolitos secundarios como factores de virulencia durante el proceso patogenico en insectos. En este estudio se analizaron once cepas de B. bassiana para determinar la presencia de los genes bbBeas y bbBsls productores de los depsipeptidos ciclooligomericos no ribosomales beauvericina y bassianolida respectivamente. Los genes fueron determinados por PCR y caracterizados por secuenciacion. Se obtuvieron extractos a partir del micelio y la presencia de la beauvericina y la bassianolida se determino por espectrometria de masas. Los resultados indicaron que con excepcion de la cepa 2857, todas poseen los dos genes. En ningun caso se produjo la beauvericina y solo la cepa 1149 produjo la bassianolida. La mortalidad causada por las conidias en larvas neonatas de Spodoptera exigua y S. frugiperda fue variable, las cepas 1512, 2253 y 2857 causaron mortalidades estadisticamente iguales y significativamente mayores que las demas cepas, con una valor promedio de 44 % de mortalidad. El extracto que contenia la bassianolida fue inyectado a la concentracion de 1 mg/ml y causo una mortalidad maxima de 26 % en larvas de S. exigua. No obstante que las cepas poseen ambos genes, la falta de produccion de estos metabolitos, con excepcion de la cepa 1149, puede deberse al requerimiento de otro tipo de condiciones de cultivo que estimulen la expresion de los genes. Hasta ahora no se observa correlacion entre la actividad patogenica del hongo y la presencia o ausencia de estos metabolitos secundarios. EnglishBeauveria bassiana is an entomopathogenic fungus that produces secondary metabolites as virulence factors during the pathogenic process in insects. In this study, eleven strains of B. bassiana were analyzed to determine the presence of the bbBeas and bbBsls genes that produce beauvericin and bassianolide non-ribosomal cyclooligomeric depsypeptides, respectively. The genes were characterized by PCR and DNA sequencing. The presence of beauvericin and bassianolide from mycelial extracts were determined by mass spectrometry. The results indicated that with the exception of strain 2857, they all possess both genes and synthesized bassianolide. Beauvericin was not produced in any case. Mortality caused by conidia in Spodoptera exigua and S. frugiperda neonate larvae was variable. Strains 1512, 2253 and 2857 caused significantly higher mortalities (44 % mortality on average). The bassianolide extract injected (1 mg/mL) caused 26 % mortality in S. exigua. The lack of beauvericin production, with the exception of strain 1149, may be due to the requirement of other culture conditions that stimulate the expression of the genes. So far, no correlation is observed between the pathogenic activity of the fungus, and the presence or absence of these secondary metabolites.

his study aims to evaluate the predatory behavior, preference and functional response of S. aurantiacus in color polymorphism larvae of S. exigua. The predatory behavior and preference test of S. aurantiacus using green and dark brown color larvae of S. exigua. Functional response test was carried out with 5 treatments of larvae population density with 10 replications. The results showed that S. aurantiacus prefers to dark brown larvae of S. exigua than green. The time taken by predators to find the first and subsequent prey was faster in dark brown larvae than in green, both on low or high larval density. The search time for the first prey on dark brown larvae was 22.7 minutes (at high density) and 39.3 minutes (at low density) while those on green larvae were 26.5 minutes and 42.7 minutes. S. aurantiacus showed type-II functional response to the density rate of S. exigua larvae both dark brown and green with the line equation respectively Y = 1,284x / 1 + 0,056x; R2: 0.96; a: 0,107; Th: 0.52 (dark brown larvae) Y = 1.32x / 1 + 0.063x; R²: 0.952; a: 0,109; Th: 0.58 (green larvae).

Spodoptera exigua Hubner is one of the most important agricultural pests in Thailand. The present study investigated the toxicity of crude extracts and phenylpropanoid compounds of A. galanga (Zingiberaceae) against S. exigua. After 24 h of a topical application bioassay on secondary instar larvae, the ethyl acetate extract estimation of the LD50 of A. galanga (Zingiberaceae) showed toxicity toward secondary instar S. exigua larvae (LD50 ~ 2.44 µg/larva). Phenylpropanoid compounds were isolated from the ethyl acetate A. galanga crude extract which has [1’S]-1’-acetoxychavicol acetate as highest toxicity (LD50 of 1.93 µg/larvae). [1’S]-1’-acetoxychavicol acetate also showed carboxylesterase activity inhibition. Thus, the ethyl acetate extract of A. galanga may have [1’S]-1’-acetoxychavicol acetate as an active ingredient for controlling this pest, which could be used as an alternative to application of environmentally insecticides for controlling S. exigua.

The beet armyworm, Spodoptera exigua Hübn. (Lepidoptera: Noctuidae) is a major insect pest of shallot in Java. This research was aimed to determine how insecticides were used as the common farmers practice for controlling S. exigua. The research was conducted in three shallot production centers in Java: the Districts of Brebes (Central Java Province), Nganjuk (East Java Province), and Bantul (the Special Region of Yogyakarta). Surveys were conducted by interviewing thirty shallot farmers as respondents from each district. The selected thirty farmers were taken from four sub-districts. Almost all farmers (93.3%) in the three districts had similar perception that S. exigua was the major insect pest in shallot and 84.4% farmers stated that this insect was difficult to control. The four most common insecticides active ingredients used were chlorfenapyr, methomyl, chlorpyrifos, and emamectin benzoate. Insecticides remained the first choice and they were applied throughout the shallot season mostly based on the calendar (1-3 days interval). When using insecticides farmers tend to exceed the label recommended rates, and the farmers mostly mixed different insecticides into one spray solution. These results suggest that application of insecticides to control S. exigua was already exessive. The potential risks and efforts essential to minimize the risks are discussed.

Spodoptera exigua is a migrant pest that attacks onions simultaneously in groups. The utilization of papaya leaves to control pests due to papaya leaves have toxic compounds that can kill pests. This study aims to measure the ability of papaya leaves to control S. exigua larvae. This research was conducted using a completely randomized design (CRD) experimental method with two treatment factors. The first factor was papaya leaf concentration (0 g / l, 30 g / l, 70 g / l, 100 g / l, 120 g / l), and the second factor is a mixture of kerosene. The treatment was repeated three times. The study was conducted at the Agrotechnology Laboratory, Agriculture Faculty Muhammadiyah University, South Tapanuli. The results showed that papaya leaves could kill S. exigua larvae. The highest mortality of S. exigua worms There were statistically significant non-treatments among treatments.

Melanization is an important innate immune defense mechanism of insects, which can kill invading pathogens. Most pathogens, for their survival and reproduction, inhibit the melanization of the host. Interestingly, our results suggested that after infection with Heliothis virescens ascovirus 3h (HvAV-3h), the speed of melanization in infected Spodoptera exigua larval hemolymph was accelerated and that the phenoloxidase (PO) activity of hemolymph in larvae infected with HvAV-3h increased significantly (1.20-fold at 96 hpi, 1.52-fold at 120 hpi, 1.23-fold at 144 hpi, 1.12-fold at 168 hpi). The transcription level of the gene encoding S. exigua prophenoloxidase-1 (SePPO-1 gene) was upregulated dramatically in the fat body during the middle stage of infection. In addition, when melanization was inhibited or promoted, the replication of HvAV-3h was inhibited or promoted, respectively. In conclusion, infection with HvAV-3h can markedly induce melanization in the middle stage of infection, and melanization is helpful for HvAV-3h viral replication.

Bacillus thuringiensis Berliner 1915 (Bt) is an entomopathogenic bacterium used to control insect pest worldwide. During its life cycle, Bt produces different insecticidal proteins, among which Veg...

The genus Spodoptera is represented in Egypt by four species, which are: S. cilium, S. exigua, S. frugiperda, and S. littoralis.A taxonomic account on these species is presented to assist in their identification. Diagnostic characters of the genus and description of the species together with an illustrated key based on male and female genitalia of the species are given.

The Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, Kingella (HACEK) group genus Eikenella contained a single species, Eikenella corrodens, for many years. In November 2019, Eikenella exigua was described after recovery from a brain abscess and blood culture in Norway. Coincidentally, characterization of 22 Gram-negative bacteria resembling Eikenella from 17 Canadian patients had been underway. Seven isolates from five patients were conclusively identifiable as E. corrodens . One (NML 120819) was deemed to represent a species of the genus Eikenella most closely related to E. corrodens . Fourteen isolates had 97.6 to 98.8% similarities to E. corrodens by 16S rRNA gene sequencing, forming three distinct groups by genome analyses. The largest contained ten anaerobic isolates from eight patients recovered from blood, brain, bone and other abscesses; upon re-evaluation, this group was found to be most consistent with E. exigua . A second facultatively anaerobic clade consisted of two ocular isolates from one patient and a sinus isolate from a second patient. The third taxon consisted of a single strictly anaerobic blood culture isolate. The novel taxa, like E. corrodens , were poorly reactive biochemically and difficult to discern from each other phenotypically and chemotaxonomically, including by cellular fatty acids. MALDI-TOF (Bruker) and whole-genome sequencing were used to further characterize isolates. Draft genomes for the strains had similar DNA G+C contents (55.38–58.53 mol%) while sizes varied from 1.82 Mb to 2.54 Mb. We propose here emendations of the genus Eikenella and the species Eikenella exigua , as well as describing Eikenella halliae sp. nov. NML 130454T (=LMG 30894T=NCTC 14180T) and Eikenella longinqua sp. nov. NML 02-A-017T (=LMG 30896T=NCTC 14179T), on the basis of these findings.

Resumen Introducción. El gusano cogollero, Spodoptera frugiperda, es una de las plagas más devastadoras a nivel mundial. Aunque de origen americano, este insecto amenaza la seguridad alimentaria de todo el orbe. La razón es que su polifagia y adaptabilidad se combinan con los efectos del cambio climático. En Costa Rica las especies del orden Spodoptera son consideradas plagas menores en el cultivo de la caña de azúcar; no obstante, existe un desconocimiento sobre la dinámica poblacional de polillas de este género. Objetivo. Monitorear las poblaciones de las especies S. frugiperda, S. sunia y S. exigua en una plantación de caña de azúcar. Materiales y métodos. El estudio se efectuó en una plantación de caña de azúcar variedad CC 01-1940, ubicada en Guanacaste, Costa Rica, entre febrero de 2018 y mayo de 2019. Se emplearon trampas con feromonas sexuales formuladas para S. frugiperda, S. sunia y S. exigua, cada feromona correspondió a un tratamiento y se colocaron diez repeticiones de cada uno. Se comparó la abundacia de cada especie y se correlacionó con distintas variables climatológicas. Resultados. El mayor porcentaje de capturas correspondió a S. frugiperda, seguido por S. sunia, mientras que las capturas de S. exigua fueron marginales. Tanto para S. frugiperda como para S. sunia, los meses de la estación seca favorecieron mayores poblaciones, por lo que factores como mayor temperatura promedio, amplitud térmica y menor humedad relativa se asociaron con mayores capturas en las trampas. Conclusiones. Aumentos en la temperatura promedio y disminución de periodos de lluvia, podrían incrementar la incidencia del género Spodoptera como plagas en la producción cañera. Abstract Introduction. The fall armyworm, Spodoptera frugiperda, is one of the world’s most devastating pests. Although originally from the Americas, this insect has become a global food security threat. The reason is that its polyphagia and adaptability combine with the effects of climate change. In Costa Rica, the species of the Spodoptera order, are considered minor pests in sugarcane production. Nevertheless, there is a knowledge gap in population dynamics of the moths of this genus. Objective. Monitor the populations of S. frugiperda, S. sunia, and S. exigua species in a sugarcane field. Materials and methods. The study was conducted in a sugarcane plantation of the variety CC 01-1940, located in Guanacaste, Costa Rica between February 2018 and May 2019. Sexual pheromone-baited traps formulated for S. frugiperda, S. sunia, and S. exigua were used, each pheromone corresponded to a treatment and ten replicates of each one were established. The abundance of each species was compared and correlated with several climatological variables. Results. The highest percentage of catches corresponded to S. frugiperda, followed by S. sunia, while the captures of S. exigua were marginal. For both S. frugiperda and S. sunia, the dry season months favored larger populations, so factors such as higher average temperature, thermal amplitude, and lower relative humidity were associated with higher captures in the traps. Conclusions. Increases in the average temperature and decrease in rainfall periods could increase the incidence of Spodoptera genus as pests in sugarcane production.

Apoptosis plays critical roles in multiple biological processes in multicellular organisms. Caspases are known as important participators and regulators of apoptosis. Here, four novel caspase genes of Spodoptera exigua were cloned and characterized, which were designated as SeCasp-1, SeCasp-6, SeCasp-7 and SeCasp-8. Analysis of the putative encoded protein sequences of these SeCasps indicated that SeCasp-1 and SeCasp-7 were possible homologs of executor caspases; SeCasp-8 was a possible homolog of initiator caspases; and SeCasp-6 was a unique caspase of S. exigua that shares low similarity with all the identified insect caspases. Based on baculovirus expression system analyses, SeCasp-1 exhibited similar caspase activity to human caspase-1, -3, -4, -6, -8 and -9; SeCasp-6 presented similar caspase activity to human caspase-2, -3, -4, -6, -8 and -9; SeCasp-7 exhibited similar caspase activity to human caspase-2, -3 and -6; and SeCasp-8 presented similar caspase activity only to human caspase-8. Induction with different chemicals revealed that SeCasp-1 showed extreme upregulation after 24 h in the treated fat body cell line (IOZCAS-Spex-II) of S. exigua. Developmental expression analysis revealed that SeCasp-1 was highly transcribed in the larval stages, while SeCasp-6, SeCasp-7, SeCasp-8 were down-regulated. The in vivo detection of the relative expression levels of SeCasps in S. eixgua larvae inoculated with different pathogens suggested that SeCasp-1 was sensitive to Bacillus thuringiensis infection and that SeCasp-6 was sensitive to baculovirus infection. SeCasp-7 and SeCasp-8 showed slight changes under either in vitro chemical apoptosis induction or in vivo pathogen infection.

The aim of our study was to determine the usefulness of mixtures of carvacrol and Bacillus thuringiensis crystalline proteins Cry against pests of two different species: Cydia pomonella L. (Lepidoptera: Tortricidae) and Spodoptera exigua Hübner (Lepidoptera: Noctuidae). The novelty of our work lies in showing the interactions between carvacrol and bacterial toxins against insect pests. Moreover, we have demonstrated that carvacrol applied via ingestion exerts toxicity against lepidopteran caterpillars. We have shown that the botanical compound and Cry proteins act in synergy and their mixtures are most effective in reducing the number of L1 and L3 larvae when B. thuringiensis toxins constitute up to 0.1% and 0.05% of the mixtures, respectively. Carvacrol and crystalline proteins act in synergy in these combinations and have the potential to be effective in protecting crops against lepidopteran pests. The nature of the interaction between the components depended on the proportion of their concentrations in the mixture. Mixtures containing Cry toxin concentrations equal or higher than 20% caused lower observed mortality of insects compared to the expected one. Furthermore, we showed that crystalline proteins of B. thuringiensis MPU B9, carvacrol and their mixture did not affect the morphology of insect haemocytes, and additionally, had no effect on the immune system.

Understanding the population growth patterns of Spodoptera exigua on alternate host plants can provide valuable information for developing an effective pest management program. In this study, using...

The contact zones of the distribution ranges of closely related reptile taxa are the source of valuable data on the microevolutionary processes in populations, the history of regional faunas origin, and the environmental preferences of the studied forms. Our study is focused on the genetic structure of the populations of sand lizard, Lacerta agilis Linnaeus, 1758, at the Crimean peninsula. This lacertid species inhabits the mountain (afforested) and plain (steppe) parts of the Crimea, being abundant or common in many areas. Lacerta agilis is represented in the Crimea by two subspecies: the widely distributed Eastern (L. a. exigua Eichwald, 1831) inhabiting a large part of Northern Eurasia, and the endemic (L. a. tauridica Suchow, 1927) residing in the Crimean mountains. Mitochondrial haplogroup affiliation corresponding to one of the subspecies (L. a. tauridica, L. a. exigua or L. a. chersonensis) was established for 225 L. agilis individuals from 81 localities in the Crimea and adjacent mainland territories. The nucleotide sequences of the complete cytochrome b gene of mitochondrial DNA (1143 bp) were studied in 75 L. agilis individuals from 68 localities. The genetic distance between both subspecies inhabiting the Crimea revealed by used molecular marker comprised 2.8%, which indicates their early divergence approximately at the transition of Early to Middle Pleistocene (ca. 1 Mya). L. a. tauridica is characterized by a comparatively deep genetic structure. Haplotypes occupying isolated positions on the phylogenetic tree of this subspecies were found in the south-western part of the Crimean Mountains, what might be explained by the localization of L. agilis microrefugia in areas least affected by the Late Pleistocene cooling. Genetic structure of L. a. exigua is more homogeneous. Another important result of our study was an identification of zones of haplogroups «exigua» and «tauridica» coexistence localized along the northern and eastern margins of the Crimean Mountains. The portion of the «exigua» haplogroup in local populations decreases southward and westward. The observed pattern of the spatial distribution of haplogroups seems to be a result of the hybridization zone formation between the sand lizard subspecies during the Holocene expansion of L. a. exigua. Ecological niches modeling for L. agilis subspecies and analysis of morphological variability of the lizards support the hypothesis of L. a. exigua and L. a. tauridica hybridization in the area of contact of their ranges in the eastern part of the Crimean Mountains.

We herein describe the first novel species within the genus Eikenella since it was established in 1972 by the reclassification of ‘Bacteroides corrodens’ to Eikenella corrodens . From a polymicrobial brain abscess, we encountered an Eikenella isolate, PXXT, that could not validly be named E. corrodens . The isolate grew on blood agar with small, translucent, pitting colonies after 3 days of anaerobic incubation. By reviewing previously collected invasive isolates, we found an additional Eikenella strain, EI-02, from a blood culture exhibiting the same properties as PXXT. Phylogenetic analyses based on both whole genome and individual house-keeping genes confirmed that the two strains allocate in a phylogenetic cluster separate from E. corrodens . Using specific amplification and sequencing of the Eikenella nusG gene, we further detected the novel Eikenella species in six historic brain abscesses previously reported to contain E. corrodens based on 16S metagenomics. Out of 24 Eikenella whole-genome projects available in GenBank, eight cluster together with PXXT and EI-02. These isolates were recovered from brain abscess (n=2), blood (n=1), bone/soft tissue (n=3), parotid gland (n=1) and unknown (n=1). It remains to be investigated whether the new species can cause endocarditis. The average nucleotide identity value between strain PXXT and the E. corrodens type strain ATCC 23834T was 92.1 % and the corresponding genome-to-genome distance value was 47.1 %, both supporting the classification of PXXT as a novel species. For this species we propose the name Eikenella exigua. The type strain of E. exigua is PXXT (DSM 109756T, NCTC 14318T).

Phloem systemicity is a desirable property for insecticides to control sucking insects. However, the development of phloem systemic insecticides is challenging. One possible strategy is to link existed insecticides with endogenous substances so that the resulting conjugates can be transported by specific transporters into the phloem. In this study, novel dipeptide promoieties were introduced into chlorantraniliprole, which is an efficient and broad-spectrum anthranilic diamide insecticide without phloem mobility. Twenty-two new dipeptide-chlorantraniliprole conjugates have been synthesized. Systemic tests showed that all conjugates exhibited phloem mobility in Ricinus communis. In particular, compound 4g with alanyl-alanine dipeptide fragment was able to accumulate in phloem sap (114.49 ± 11.10 μM) in the form of its hydrolysis product 5g. Results of bioassay showed that conjugates 4g and 5g were able to exhibit comparable insecticidal activity against Plutella xylostella L. and Spodoptera exigua compared to its parent compound chlorantraniliprole. This work demonstrated that the dipeptide structures were able to contribute to the improvement of the uptake and phloem mobility of chlorantraniliprole, and two phloem mobile conjugates with satisfactory in vivo insecticidal effect was obtained as new candidates for high-efficient insecticides.

BACKGROUND: The beet armyworm, Spodoptera exigua, is a serious agricultural pest that is primarily controlled using chemical insecticides. Recently, resistance to the insecticide spinosad has been described in S. exigua field populations. To date, there has been no functional evidence proving the involvement of the nicotinic acetylcholine receptor (nAChR) α6 mutation in spinosad resistance in S. exigua. RESULTS: In this study, using the CRISPR/Cas9 genome‐editing system, a homozygous strain (Seα6‐KO) with approximately 1760‐bp deletion within Seα6 in S. exigua causing a premature truncation of Seα6 was successfully constructed. Insecticide bioassays showed that Seα6‐KO exhibited 373‐fold higher resistance to spinosad and 850‐fold higher resistance to spinetoram compared to WH‐S strain with the same genetic background but showed no significant change in susceptibility to emamectin benzoate and chlorantraniliprole. Genetic analysis revealed that Seα6‐KO is inherited as an incompletely recessive trait. CONCLUSION: The results clearly demonstrated the functional role of Seα6 in resistance to spinosyn insecticides and provide an example of using genome editing to verify a target premature truncation associated with resistance.