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Leaf-cutting ants (Formicidae; Atta spp., Acromyrmex spp.) cut off pieces of leaves and other plant tissue and feed it to their symbiotic fungi. As this foraging behavior poses an imminent threat to agriculture, leaf-cutting ants are considered as pests of huge ecologically and economically importance. Consequently, research on leaf-cutting ants focused on their foraging decisions and interactions with their cultivated symbiotic fungi, whereas their effect on the attacked plants, apart from the loss of plant tissue, remains largely unknown. In this study, we investigated the consequences of an attack by leaf-cutting ants and analyzed the plants' defense responses in comparison to chewing caterpillars and mechanical damage. We found that an attack by leaf-cutting ants induces the production of jasmonates in several host and non-host plant species (Arabidopsis thaliana, Vicia faba, Phaseolus lunatus, Tococa quadrialata). Additionally, we showed in the natural host plant lima bean (P. lunatus) that leaf-cutting ant damage immediately leads to the emission of typical herbivory-induced plant volatiles, including green leaf volatiles and terpenoids. Further data exploration revealed clear differences in the defense-related phytohormone profile in plant species of Neotropical and Eurasian origin. Taken together, we show that leaf-cutting ant infestation and their way of clipping the plants' tissues induce jasmonate and jasmonates-mediated responses and do not differ from those to mechanical injury or larval feeding. [ABSTRACT FROM AUTHOR]

Soybean (Glycine max) is the world's most cultivated legume; currently, most of its varieties are Bt. Spodoptera spp. (Lepidoptera: Noctuidae) are important pests of soybean. An artificial neural network (ANN) is an artificial intelligence tool that can be used in the study of spatiotemporal dynamics of pest populations. Thus, this work aims to determine ANN to identify population regulation factors of Spodoptera spp. and predict its density in Bt soybean. For two years, the density of Spodoptera spp. caterpillars, predators, and parasitoids, climate data, and plant age was evaluated in commercial soybean fields. The selected ANN was the one with the weather data from 25 days before the pest's density evaluation. ANN forecasting and pest densities in soybean fields presented a correlation of 0.863. It was found that higher densities of the pest occurred in dry seasons, with less wind, higher atmospheric pressure and with increasing plant age. Pest density increased with the increase in temperature until this curve reached its maximum value. ANN forecasting and pest densities in soybean fields in different years, seasons, and stages of plant development were similar. Therefore, this ANN is promising to be implemented into integrated pest management programs in soybean fields. [ABSTRACT FROM AUTHOR]

During decision-making, animals may use either innate or plastic behaviours. This has been suggested to be important for generalist phytophagous insects where females need to assess a large range of cues during host plant selection for oviposition. To facilitate the choice, generalists may thus use innate preference hierarchies among host plants combined with phenotypic plasticity based on earlier host experience, but if populations differ in whether they rely on innate or plastic factors during decision-making is not well-known. Females from an Egyptian population of the polyphagous moth Spodoptera littoralis has previously been found to shift preference between plants in their innate preference hierarchy depending on larval host plant experience. We studied the innate preference hierarchy for three host plants (cotton, cabbage and cowpea), and whether the hierarchy shifts based on larval host plant experience, in a Northern range margin population (Italy) and a core population (Kenya) of S. littoralis, to see if and how these traits vary across populations. In addition, we studied larval performance on the three host plants in all three populations. The Italian and Kenyan populations had different innate preference hierarchies, and both hierarchies differed from the hierarchy that has previously been found in the Egyptian population. Furthermore, the host plant selection of ovipositing females was affected by larval diet in the Italian and Kenyan population, but the larval host plant experience did not completely shift the preference hierarchy as in the Egyptian population. This indicates that not only host plant preference per se, but also phenotypic plasticity during host plant selection can vary between populations. We further found that the populations responded differently to larval diet for some performance traits. However, it was only the Italian population that showed indications of any link between preference and performance, as they had slower development on their least preferred host plant. Overall, preference divergence between populations seems not to be driven by local variation in larval performance. [ABSTRACT FROM AUTHOR]

In this study, a powder of the larvae, pupae and adults of the fall armyworm Spodoptera frugiperda (J.E. Smith) was obtained, and 1% of this powder was added to solid culture media potato dextrose agar (PDA) and liquid media Sabouraud dextrose broth (SDB) and minimal medium (MM), to induce the development and virulence of the M1 strain of Metarhizium anisopliae (Metchnikoff) Sorokin, which is pathogenic against the L1 larvae of S. frugiperda. The pupa powder was selected because it causes the greatest degree of radial growth of the M1 strain (73.3 mm) in PDA (p < 0.05). The enzymatic activity of M1, in the medium with pupa powder of S. frugiperda (I), was increased on day 4 for the proteases in MMI (1.1 U min-1) and on day 2 for the lipases in MMI (7034 U) and SDBI (6004 U) (p<0.05). In the pathogenicity bioassay, the M1 strain grown on PDA with the pupa powder caused 90% mortality on day 4 in the L1 larvae, while M1 grown on PDA without the powder caused 50%. With the pupa powder, the growth of the M1 strain increased, which promoted the production of enzymes, thus, increasing the pathogenicity of M. anisopliae against the L1 larvae of S. frugiperda. [ABSTRACT FROM AUTHOR]

Plant resistance mechanisms to pathogens can lead to a lowered efficacy of insect microbial biocontrol agents, but the influence of plant variety has been little-studied. Leaves and stalks from twelve maize (Zea mays L.) inbreds with different plant pathogen resistance were evaluated for their influence on the efficacy of Beauveria bassiana (Bals.-Criv.) Vuill. against European corn borers (Ostrinia nubilalis (Hübner)). For leaf assays with first instar caterpillars, mortality on day 2 ranged from an inbred-dependent high of 76.1% to a low of 10.0% for European corn borers in leaf assays. For stalk assays with third instar caterpillars, mortality on day 4 ranged from an inbred dependent high of 83.0% and 75.0% to a low of 0.0% and 8.3% for fall armyworms and European corn borers, respectively. Lesion size ratings due to Fusarium graminearum (Schwabe) applied to tissues were often significantly correlated with the mortality levels of B. bassiana-treated caterpillars that fed on leaves and stalks. This study suggests that the influence of plant varieties on the efficacy of insect microbial pathogens can vary depending on the insect species involved and the plant tissue, and this is worth considering when new plant varieties and biocontrol strains are being developed whenever practical. [ABSTRACT FROM AUTHOR]

An early instar larva of Spodoptera ornithogalli (Guenée) was collected from spearmint, Mentha spicata (Lamiales: Lamiaceae), and reared to adult in Mecklenburg County, North Carolina. A female S. ornithogalli was collected from the same locality and laid eggs. Her offspring were reared successfully on this host. This is the first record of S. ornithogalli using Lamiaceae as a hostplant outside of the laboratory, so the agricultural and regulatory implications of this record are examined. Identification of the immature stages of S. ornithogalli is difficult with the existing literature. We illustrate key larval, pupal, and adult characters of the original specimen found on M. spicata and discuss morphological characters to distinguish S. ornithogalli from related species throughout its range. [ABSTRACT FROM AUTHOR]

The invasive fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), poses a significant global threat with serious economic implications. Global concern heightened following the first major outbreak in Africa in 2016. Our research, which confirmed the presence of FAW in Indonesia in 2015 through re-examined samples from a maize field in Lampung region of Indonesia, supports the hypothesis that the invasion pattern does not follow the predicted west-to-east chronological timeline. Historical records and reidentification suggest that FAW may have been established in Indonesia, Africa, and Australia as early as nineteenth century, suggesting its potential presence in these regions much earlier than previously thought. The spread of FAW could be linked to the movement of people and plants such as maize or Para grass (Brachiaria mutica), at least at the end of the nineteenth century. This underscores the importance of rigorous identification methods for accurately tracking invasive species like FAW. Analyzing these historical records alongside the genetic structure of populations in Southeast Asia, particularly in Indonesia, is crucial for future research aimed at developing effective management strategies to mitigate the impact on the global agriculture. [ABSTRACT FROM AUTHOR]

Nutrition is vital to health, but while the link between diet and body nutritional composition is well explored in humans and other vertebrates, this information is not well understood in insects, despite the vital roles they play in ecosystems, and their increasing use as experimental models. Here we used Nutritional Geometry to explore the rapid physiological response to ingested nutrients in the haemolymph nutritional profile of Spodoptera littoralis caterpillars. We ask whether blood nutrients are maintained homeostatically in the face of variable nutritional intake, or if regulation is more flexible for some nutrients than others (allostasis), which allows animals to adapt to stress by responding in a way that prioritises efficiency of responses in the face of trade‐offs. Caterpillars were placed on 1 of 20 diets, systematically varying in their nutrient ratios (protein: carbohydrate) and density (calorie content), and their consumption was measured. After 48 h, caterpillars were bled, and the macronutrient (protein, carbohydrates and lipids) and nutrient metabolite (amino acids and simple sugars) content of the haemolymph was measured. Proteins comprised 93% of the haemolymph macronutrient pool on average and their concentration increased with protein eaten. The amino acid (AA) pool was dominated by five AAs, and the total pool increased with total nutrient intake. However, the ratio of essential to non‐essential AAs increased as the proportion of protein consumed increased. Carbohydrates were tightly controlled, increasing only on the most extreme carbohydrate intakes. Simple sugars were dominated by glucose and trehalose, and overall, the simple sugar pool showed high levels of homeostasis. Rather than strict homeostasis of blood nutritional properties, an allostatic model seemed to be a better fit for blood nutrient regulation in this generalist herbivore. This flexibility in response to the nutritional composition of the diet may, in part, explain how this species has evolved to extreme dietary generalism and may play a role in its worldwide pest status. Given the range of fitness‐related processes affected by the haemolymph, future studies should examine the physiological impacts of blood nutrient variation on reproduction, growth and response to infection and the trade‐offs between them. [ABSTRACT FROM AUTHOR]

Plant resistance mechanisms to pathogens can lead to a lowered efficacy of insect microbial biocontrol agents, but the influence of plant variety has been little-studied. Leaves and stalks from twelve maize (Zea mays L.) inbreds with different plant pathogen resistance were evaluated for their influence on the efficacy of Beauveria bassiana (Bals.-Criv.) Vuill. against European corn borers (Ostrinia nubilalis (Hübner)). For leaf assays with first instar caterpillars, mortality on day 2 ranged from an inbred-dependent high of 76.1% to a low of 10.0% for European corn borers in leaf assays. For stalk assays with third instar caterpillars, mortality on day 4 ranged from an inbred dependent high of 83.0% and 75.0% to a low of 0.0% and 8.3% for fall armyworms and European corn borers, respectively. Lesion size ratings due to Fusarium graminearum (Schwabe) applied to tissues were often significantly correlated with the mortality levels of B. bassiana-treated caterpillars that fed on leaves and stalks. This study suggests that the influence of plant varieties on the efficacy of insect microbial pathogens can vary depending on the insect species involved and the plant tissue, and this is worth considering when new plant varieties and biocontrol strains are being developed whenever practical.

Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), a threat to maize production systems, is a polyphagous pest of global significance. There is no registered bioinsecticide of botanical origin to provide green remedy against this pest of concern. The present study reports for the first time the potency of the polar and non-polar bioinsecticidal leads sourced from Lippia alba (Mill.) N.E. Br. leaves. Shade-dried leaves of L. alba were extracted and evaluated; based on preliminary bioassay, the ethyl acetate leaf extract of L. alba (LEAE) was found to be the most potent against FAW in the in vitro and in vivo studies. Ultraperformance liquid chromatography-quadrupole time-of-flight-mass spectrometric (UPLCQToF-MS) analysis of LEAE revealed the rich chemical profile of 28 compounds, dominated by flavones, namely, naringenin, trihydroxy-dimethoxy flavone, and dihydroxy-trimethoxy flavone. Among others, glycosides, such as clerodendrin, calceolarioside E, forsythoside B, geniposide, and martynoside, and glucuronides, such as luteolin-7-diglucuronide, tricin-7-O-glucuronide, and luteolin-7-Oglucuronide, were also identified. LEAE exhibited exceptionally high in vitro [LC50 = 6,900 parts per million (ppm)] and in vivo (computed as damage score on a scale of 1-9) insecticidal activity against S. frugiperda, with no phytotoxicity at a dose as high as 20 times of LC50. LEAE also exhibited significant antifeedant, ovicidal, and growth regulatory activity at the 70-16,000 ppm (w/v) concentration range. In silico assessment revealed strong binding of martynoside, calceolarioside E, and forsythoside B with acetylcholinesterase-, sodium-, and chloride-dependent gaminobutyric acid (GABA) receptor and ryanodine receptor, respectively, facilitated by hydrogen bonds (conventional and C-H bonds) stabilized by hydrophobic pi-sigma, pi-pi stacked, pi-alkyl, and alkyl interactions. The present study established L. alba as a potential bioresource and secondary metabolite enriched LEAE as bioinsecticide for further product development. [ABSTRACT FROM AUTHOR]

The article presents a study which examined the presence of Nucleopolyhedrovirus (NPV) infected Spodoptera frugiperda larvae in order to manage the invasive pest the fall armyworm, Spodoptera frugiperda in north India. Topics discussed include isolation and purification of polyhedral occlusion bodies (POBs), evaluation of the most potent virus isolate, and natural incidence of NPV in Spodoptera frugiperda larvae collected from different zones of Jammu and Kashmir, India.

In Sinaloa, Mexico, the fall armyworm Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) causes economic losses during two agricultural cycles per year. The insecticidal potential and antifeedant effect of the ethanolic extracts of Swietenia humilis (Zucc), Azadirachta indica (A. Juss), and Argemone mexicana (L.), were evaluated against the third instar larvae of S. frugiperda by applying an ethanolic extract of these plants at concentrations of 5% and 10% and comparing them to water that contained Tween 80 to 01%. The larvae began dying 48 h after application. At 120 h, 10% extracts of Azadirachta indica and Swietenia humilis resulted in 80% and 73% mortality, respectively. A 10% extract of Argemone mexicana simultaneously produced 53% mortality. A larval antifeedant effect was observed from the weight of the S. frugiperda diet at the beginning, and the weight of the unconsumed diet to 120 h after exposure showed that exposure to a 10% extract of Swietenia humilis and 5% of Azadirachta indica resulted in a residual diet weight of 0.207 g and 0.204 g, respectively, compared to the control (0.177 g). The larval mortality and antifeedant effects were attributed to the presence of metabolites of the plant's extracts. These results showed the potential insecticidal and antifeedant effects of S. humilis and A. indica (10%) on the larvae of fall armyworm. Resumen En Sinaloa, México el gusano cogollero Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) causa pérdidas económicas durante dos ciclos agricolas por año. Se evaluó el potencial insecticida y el efecto anti alimentario de extractos etanólicos de Swietenia humilis (Zucc), Azadirachta indica (A. Juss), y Argemone mexicana (L.),contra larvas de tercer instar de S. frugiperda, aplicándolos a concentraciones de 5% y 10% comparándolos con agua y Tween 80 al 01%. La mortalidad de larvas comenzó 48 h después de la aplicación, y a las 120 h, Azadirachta indica y Swietenia humilis al 10% tuvieron 80% y 73% de mortalidad. Argemone mexicana al 10% produjo 53% de mortalidad durantel mismo tiempo. El efecto anti alimentario en larvas de S. frugiperad se observó al pesar la dieta al inicio del bioensayo y pesando la dieta no consumida a las 120 h, mostrando que Swietenia humilis al 10% y Azadirachta indica al 5% tuvieron un peso residual de dieta de (0.207 g) y (0.204 g) respectivamente, comparada con el control (0.177 g). La mortalidad de larvas y el efecto anti alimetario se atribuye a la presencia de metabolitos de las plantas. Estos resultados muestran el potencial insecticida y el efecto anti alimentario de S. humilis y A. indica al 10% sobre larvas del gusano cogollero. [ABSTRACT FROM AUTHOR]

Phytophagous insects have evolved sophisticated detoxification systems to overcome the antiherbivore chemical defenses produced by many plants. However, how these biotransformation systems differ in generalist and specialist insect species and their role in determining insect host plant range remains an open question. Here, we show that UDP-glucosyltransferases (UGTs) play a key role in determining the host range of insect species within the Spodoptera genus. Comparative genomic analyses of Spodoptera species that differ in host plant breadth identified a relatively conserved number of UGT genes in generalist species but high levels of UGT gene pseudogenization in the specialist Spodoptera picta. CRISPR-Cas9 knockouts of the three main UGT gene clusters of Spodoptera frugiperda revealed that UGT33 genes play an important role in allowing this species to utilize the poaceous plants maize, wheat, and rice, while UGT40 genes facilitate utilization of cotton. Further functional analyses in vivo and in vitro identified the UGT SfUGT33F32 as the key mechanism that allows generalist S. frugiperda to detoxify the benzoxazinoid DIMBOA (2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one), a potent insecticidal phytotoxin produced by poaceous plants. However, while this detoxification capacity is conserved in several generalist Spodoptera species, Spodoptera picta, which specializes on Crinum plants, is unable to detoxify DIMBOA due to a nonfunctionalizing mutation in SpUGT33F34. Collectively, these findings provide insight into the role of insect UGTs in host plant adaptation, the mechanistic basis of evolutionary transitions between generalism and specialism and offer molecular targets for controlling a group of notorious insect pests. [ABSTRACT FROM AUTHOR]

Simple Summary: Spodoptera exempta is a global agricultural invasive pest which posing a serious threat to the planting area of major crops of maize, wheat and rice. Our study predicted the potential suitable areas for S. exempta globally based on 841 global occurrence records and eight important bioclimatic variables, and analyzed the overlap with maize, wheat and rice planting areas. The results of the study indicate that the high potential suitable areas of S. exempta are mainly distributed in developing countries (Latin America, central South America, Central Africa, and southern Asia), with the greatest impact on global maize planting areas, followed by rice and wheat. Global warming will have a smaller limitation on the distribution of S. exempta. In view of the global potential geographic distribution of S. exempta and its damage to three major crops, the above governments of various countries should pay active attention to the prevention and control of S. exempta to protect global food security. Spodoptera exempta, known as the black armyworm, has been extensively documented as an invasive agricultural pest prevalent across various crop planting regions globally. However, the potential geographical distribution and the threat it poses to host crops of remains unknown at present. Therefore, we used an optimized MaxEnt model based on 841 occurrence records and 19 bioclimatic variables to predict the potential suitable areas of S. exempta under current and future climatic conditions, and the overlap with wheat, rice, and maize planting areas was assessed. The optimized model was highly reliable in predicting potential suitable areas for this pest. The results showed that high-risk distribution areas for S. exempta were mainly in developing countries, including Latin America, central South America, central Africa, and southern Asia. Moreover, for the three major global food crops, S. exempta posed the greatest risk to maize planting areas (510.78 × 104 km2), followed by rice and wheat planting areas. Under future climate scenarios, global warming will limit the distribution of S. exempta. Overall, S. exempta had the strongest effect on global maize production areas and the least on global wheat planting areas. Our study offers a scientific basis for global prevention of S. exempta and protection of agricultural crops. [ABSTRACT FROM AUTHOR]

Fall armyworm is one of the main pests of maize, and in all regions where it is distributed, is a limiting factor for productivity. In this study, a method to monitor this pest maize crops, was proposed. The method allowed us to randomly cover representative points of a crop field from planting until high incidence of damage by fall armyworm larvae and allowed us to determine the percentage of damage in perimeter areas and the center of a crop in field. A maize crop, surrounded by a mango orchard, a cattle grazing paddock, and other maize fields was monitored. Most maize plants were damaged adjacent to mango (23.7 – 29.6%), followed by maize surrounded by maize (20 – 21.9%), and maize adjacent to a cattle grazing paddock had fewest damaged plants (13.1 – 16.4%). Results suggested that timely control of the pest is necessary to avoid total crop damage. Surrounding crops significantly affect damage caused by S. frugiperda larvae to maize plants. Crops that allow development of diverse herbaceous plants, shrubs, and other, such as mango crops, could be a suitable ecosystem for establishing niches of insects (mostly beneficial), as observed in this study. The results are essential to implement in regions where maize is grown near surrounding crops, for timely control of fall armyworm. El gusano cogollero es una de las principales plagas del maíz y, en todas las regiones donde se distribuye, es un factor limitante para la productividad. En este estudio se propuso un método para monitorear esta plaga en los cultivos de maíz. El método nos permitió cubrir aleatoriamente puntos representativos de un campo de cultivo desde la siembra hasta la alta incidencia de daño por larvas de gusano cogollero y nos permitió determinar el porcentaje de daño en las áreas perimetrales y el centro de un cultivo en el campo. Se monitoreó un cultivo de maíz que estaba rodeado por una huerta de mango, un potrero de pastoreo de ganado y por otros campos de maíz. La mayoría de las plantas de maíz resultaron dañadas junto al mango (23.7 – 29.6%), seguidas por el maíz rodeado de maíz (20 – 21.9%), y el maíz adyacente a un potrero de pastoreo tuvo la menor cantidad de plantas dañadas (13.1 – 16.4%). Los resultados sugirieron que es necesario un control oportuno de la plaga para evitar el daño total al cultivo. Los cultivos circundantes afectan significativamente el daño causado por las larvas de S. frugiperda a las plantas de maíz. Los cultivos que permiten el desarrollo de diversas plantas herbáceas, arbustos y otras, como el cultivo de mango, podrían ser un ecosistema adecuado para el establecimiento de nichos de insectos (en su mayoría benéficos), como se observa en este estudio. Es esencial implementar los resultados en regiones donde se cultiva maíz cerca de cultivos circundantes, para el control oportuno del gusano cogollero. [ABSTRACT FROM AUTHOR]

The present study evaluated the biological control of seed extracts and chemical compounds of physic nut, Jatropha curcas through insecticidal and insectistatic activity against the armyworm, Spodoptera frugiperda. Gas chromatography-mass spectrometry analysis showed that major constituents of the hexanic extract were oleic (40.3% 2 µL extract / 10 ml solvent (v/v)), linoleic (27.3%), and palmitic (15.8%) fatty acids, while the major constituents of the acetonic extract were oleic (47.6%), linoleic (32.8%), and palmitic (14.3%) acids. In an ingestion bioassay with neonate S. frugiperda, the extracts were evaluated at six concentrations (0, 100, 250,1,000, 2,500, and 5,000 ppm). The fatty acid extracts induced a positive relationship where the higher the concentration, the greater the effect on larval and pupal weight, the development of the larvae and pupae, and larval and pupal mortality. Hexanic and acetonic extracts at 5,000 ppm caused 100% larval mortality. The oleic and linoleic fatty acids were further evaluated at (0, 100, 160, 400, 600 and 1,000 ppm). Oleic acid at 600 ppm reduced the weights of the larvae and pupae, as well as increased the mortality of the pupa, while the linoleic acid at 400 ppm reduced the weight larvae and increased mortality larval and pupal. The values of lethal concentrations fifty and ninety (LC50-LC90) of oleic and linoleic acid were 125 - 624 ppm and 199 - 630 ppm, respectively. Extracts and fatty acids from the seeds of J. curcas can be explored as useful alternatives for the control of S. frugiperda. Se evaluó el control biológico de extractos de semillas y compuestos químicos de Jatropha curcas a través de su actividad insecticida e insectistática contra el gusano cogollero, Spodoptera frugiperda. El análisis de cromatografía de gasesespectrometría de masas mostró que los principales constituyentes del extracto hexánico eran ácidos grasos oleico (40.3% de extracto de 2 µl/10 ml de disolvente (v/v)), linoleico (27.3%) y palmítico (15.8%), mientras que los principales constituyentes del extracto acetónico fueron los ácidos: oleico (47.6%), linoleico (32.8%) y palmítico (14.3%). En un bioensayo de ingestión con larvas recién nacidas S. frugiperda, los extractos se evaluaron a seis concentraciones (0, 100, 250, 1,000, 2,500 y 5,000 ppm). Los extractos de ácidos grasos indujeron una relación positiva donde a mayor concentración, mayor efecto sobre el peso larval y pupal, el desarrollo de larvas y pupas, y la mortalidad larval y pupal. Los extractos hexánico y acetónico a 5,000 ppm causaron 100% de mortalidad larval. Los ácidos grasos oleico y linoleico se evaluaron adicionalmente (0, 100, 160, 400, 600 y 1,000 ppm). El ácido oleico a 600 ppm redujo el peso de las larvas y pupas, así como aumentó la mortalidad de las pupas, mientras que el ácido linoleico a 400 ppm redujo el peso de las larvas y aumentó la mortalidad de larvas y pupas. Los valores de concentraciones letales cincuenta y noventa (LC50-LC90) de ácido oleico y linoleico fueron 125 - 624 ppm y 199 - 630 ppm, respectivamente. Los extractos y ácidos grasos de las semillas de J. curcas pueden explorarse como alternativas útiles para el control de S. frugiperda. [ABSTRACT FROM AUTHOR]

The invasion of maize (Zea mays L.) in 2018 by fall armyworm, Spodoptera frugiperda (J.E. Smith), threatened food security of India. In the early stage of crop growth, spray is difficult to apply because of the small size of the plant, waste of insecticide, and harm to non-target organisms. Seed treatment alone and combined with foliar spray were evaluated to manage fall armyworm in the field in June and September 2019. The experiment was a randomized block design with eight treatments. The maize seed treatments viz., chlorantraniliprole 250 g a.i./100 kg seeds alone, cyantraniliprole + thiamethoxam 238 g a.i./100 kg seeds, and cyantraniliprole + thiamethoxam 317 g a.i./100 kg seeds managed fall armyworm larvae and reduced plant damage 1 week after emergence of the crop compared with the check. A sequence of two foliar sprays resulted in the highest yield, followed by seed treatment plus a foliar spray (cyantraniliprole 19.8 + thiamethoxam 19.8 FS 8 ml/kg of seeds + emamectin benzoate 5 SG 0.4 g/liter), and seed treatments (chlorantraniliprole, cyantraniliprole+thiamethoxam). Most net returns were from cyantraniliprole 19.8 + thiamethoxam 19.8 FS 317 g a.i./100 kg of seeds and foliar application of emamectin benzoate 5 SG 12.5 g a.i./ha (US $581); the nontreated check had only US $123/ha net return. La invasión al maíz (Zea mays L.) en 2018 por el gusano cogollero Spodoptera frugiperda (J.E. Smith), amenazó la seguridad alimentaria de India. La aspersión de insecticidas es difícil de realizar en la etapa inicial de crecimiento del cultivo debido al tamaño pequeño de la planta, el desperdicio de insecticida y el daño a organismos no-objetivo. Se evaluó el tratamiento de semillas por sí solo y en combinación con aspersión foliar en junio y septiembre de 2019 para controlar el gusano cogollero en el campo. El experimento fue un diseño de bloques al azar con ocho tratamientos. Los tratamientos de semilla del maíz incluyendo clorantraniliprol 250 g i.a./100 kg de semillas solas, ciantraniliprol + tiametoxam 238 g i.a./100 kg de semillas y ciantraniliprol + tiametoxam 317 g i.a./100 kg de semillas redujeron las larvas del gusano cogollero y el daño a las plantas 1 semana después de la emergencia del cultivo en comparación con el control sin tratamiento. Una secuencia de dos aspersiones foliares dio como resultado el mayor rendimiento, seguido de un tratamiento de semillas más una aspersión foliar con (ciantraniliprol 19.8 + tiametoxam19.8 FS 8 ml/Kg de semillas – benzoato de emamectina 5 SG 0.4 g/litro) y tratamientosde semilla con (clorantraniliprol, ciantraniliprol + tiametoxam). La mayor parte de los rendimientos netos se observaron con ciantraniliprol 19,8 + tiametoxam 19,8 FS 317 gi.a./100 kg de semillas y aplicación foliar de benzoato de emamectina 5 SG 12,5 gi.a./ha (US $581); con el control sin tratamiento se obtuvieron solamente US $123/ha de rendimiento neto. [ABSTRACT FROM AUTHOR]

Use of microorganisms to manage insect pests is a strategy compatible with organic production, but variability in their effectiveness limits the adoption by growers. Prior reports indicated that increased resistance to a fungal plant pathogen in dent maize inbreds was associated with reduced efficacy of the commercialized fungal biocontrol agent Beauveria bassiana in killing maize caterpillar pests, but this aspect has not been investigated with sweet corn. Several varieties of sweet corn certified for organic production, along with sweet corn inbreds that have been used in breeding commercial sweet corn hybrids, were evaluated for their influence on the efficacy of two commercial strains of Beauveria bassiana. As occurred in prior dent corn studies, significant differences were noted in mortality levels on day 2 for European corn borers (ranging from as much as 14.9 to 58.6%) and fall armyworms (ranging from as much as 12.1 to 46.0%) depending on the sweet corn hybrids and inbreds. Higher rates of leaf colonization by B. bassiana were associated with larger lesion sizes caused by the maize pathogen Fusarium graminearum for both hybrids and inbreds. However, greater efficacy of B. bassiana in killing insects was associated with smaller lesion sizes caused by F. graminearum for some organic production sweet corn hybrids. This information indicates it is possible to develop sweet corn varieties that are both resistant to fungal pathogens and compatible with use of B. bassiana and suggests this aspect can be further improved to promote more effective organic production of sweet corn. [ABSTRACT FROM AUTHOR]

BACKGROUND: Temperature plays a critical role in the development and reproductive process of insects, therefore understanding how insects respond to temperature is vital for comprehending and predicting their population dynamics, particularly when it comes to agricultural pests. Spodoptera eridania Stoll is a polyphagous pest that has recently expanded its distribution beyond its native range. In this study, we assessed the impact of temperature on the reproduction of S. eridania and used the obtained data to develop an oviposition model that could be used to predict egg‐laying behavior under field conditions. The reproductive parameters were evaluated at temperatures of 15, 20, 25, 28, and 32 °C. RESULTS: Temperature had a significant impact on the reproductive parameters examined. Overall, as temperature increased, the pre‐oviposition period, oviposition period, and longevity decreased. Total fecundity exhibited a bell‐shaped response to temperature, with peak egg‐laying observed at 20 and 25 °C. In line with the experimental data, our model predicted higher rates of oviposition between 20 and 26 °C, thus reinforcing that this temperature range may represent the optimal conditions for the reproduction of S. eridania. CONCLUSION: The findings from our study provide a significant contribution to the understanding of the ecology of an important agricultural pest. The information generated can have practical applications in developing control strategies by enabling the aligning of the timing of control measures with peaks of reproductive activity. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), a threat to maize production systems, is a polyphagous pest of global significance. There is no registered bioinsecticide of botanical origin to provide green remedy against this pest of concern. The present study reports for the first time the potency of the polar and non-polar bioinsecticidal leads sourced from Lippia alba (Mill.) N.E. Br. leaves. Shade-dried leaves of L. alba were extracted and evaluated; based on preliminary bioassay, the ethyl acetate leaf extract of L. alba (LEAE) was found to be the most potent against FAW in the in vitro and in vivo studies. Ultraperformance liquid chromatography–quadrupole time-of-flight–mass spectrometric (UPLC-QToF-MS) analysis of LEAE revealed the rich chemical profile of 28 compounds, dominated by flavones, namely, naringenin, trihydroxy-dimethoxy flavone, and dihydroxy-trimethoxy flavone. Among others, glycosides, such as clerodendrin, calceolarioside E, forsythoside B, geniposide, and martynoside, and glucuronides, such as luteolin-7-diglucuronide, tricin-7-O-glucuronide, and luteolin-7-O-glucuronide, were also identified. LEAE exhibited exceptionally high in vitro [LC50 = 6,900 parts per million (ppm)] and in vivo (computed as damage score on a scale of 1–9) insecticidal activity against S. frugiperda, with no phytotoxicity at a dose as high as 20 times of LC50. LEAE also exhibited significant antifeedant, ovicidal, and growth regulatory activity at the 70–16,000 ppm (w/v) concentration range. In silico assessment revealed strong binding of martynoside, calceolarioside E, and forsythoside B with acetylcholinesterase-, sodium-, and chloride-dependent γ-aminobutyric acid (GABA) receptor and ryanodine receptor, respectively, facilitated by hydrogen bonds (conventional and C–H bonds) stabilized by hydrophobic pi–sigma, pi–pi stacked, pi–alkyl, and alkyl interactions. The present study established L. alba as a potential bioresource and secondary metabolite enriched LEAE as bioinsecticide for further product development.

Yellowstriped armyworm (YSAW), Spodoptera ornithogalli, is a polyphagous pest that infests various crops, including cotton, cabbage, corn, blackberry, grape, etc. We documented egg clusters, larvae and adults of YSAW in pecan orchards in Georgia. Until now, there have been no reports of YSAW infesting pecan and its suitability as a host. To investigate the survival, development, and reproduction of YSAW on pecan, we used the age-stage, two sex life table. The YSAW successfully completed its lifecycle on pecan with an 82% preadult survival rate. The preadult duration and mean fecundity were 47.84 d and 1212.55 offspring per female. The population parameters, including intrinsic rate of increase (r), finite rate of increase (λ), net reproduction rate (R0), and mean generation time (T) were 0.1184 d−1, 1.1257 d−1, 430.67 offspring/female, and 51.05 d, respectively. This study confirms that pecan, Carya illinoinensis, is a potential host plant of YSAW and perhaps more widespread damage could be observed. [ABSTRACT FROM AUTHOR]

During two successive sugar beet growing seasons; 2021/2022 and 2022 / 2023. This field study was carried out at the Experimental Farm of Sakha Agricultural Research Station for recording the various prey of Chrysoperla carnea (Stephens) (Neuroptera :Chrysopidae ( larvae predator by visual examination method, this predator feed upon their prey in the field. Moreover, investigated the toxicity of conventional, Clozemail, and biocides Xentari® insecticides on Spodoptera spp.) Noctuidae :Lepidoptera ( and C. carnea larvae. The obtained results proved that the total numbers of prey were 197 and 196 individuals in two seasons, respectively. The most common prey was Spodoptera spp. (Eggs + larvae), leafhoppers, aphids, Pegomyia mixta Vill. (Diptera: Anthomyiidae) larvae, and Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) throughout the two seasons. In addition, the general meaning of reductions to Spodoptera spp. Larvae population due to Clozemail® and Pleo® was (82.17 and 84.11%) and (83.33 and 89.9%) during the two seasons, respectively. While Xentari® caused (77.36 and 77.65%) in two seasons, respectively. On the other hand, the general mean reduction in C. carnea larvae numbers was (83.33 and 89.90%) for Clozemail®, and (92.32 and 89.95/) for Pleo® in two seasons, respectively. Regarding the biocide, Xentari® induced reductions to the same predators with (26.85 and 22.85%) in two seasons, respectively. In conclusion, the combination and integration between C. carnea predator and biocides application are very good tools in IPM of sugar beet insects. [ABSTRACT FROM AUTHOR]

Using the 10x Genomics Chromium single-cell RNA sequencing (scRNA-seq) platform, we discovered unexpected heterogeneity in an established cell line developed from the midgut of the Fall armyworm, Spodoptera frugiperda, a major global pest. We analyzed the sequences of 18,794 cells and identified ten unique cellular clusters, including stem cells, enteroblasts, enterocytes and enteroendocrine cells, characterized by the expression of specific marker genes. Additionally, these studies addressed an important knowledge gap by investigating the expression of genes coding for respiratory and midgut membrane insecticide targets classified by the Insecticide Resistance Action Committee. Dual-fluorescence tagging method, fluorescence microscopy and fluorescence-activated cell sorting confirmed the expression of midgut cell type-specific genes. Stem cells were isolated from the heterogeneous population of SfMG-0617 cells. Our results, validated by KEGG and Gene Ontology analyses and supported by Monocle 3.0, advance the fields of midgut cellular biology and establish standards for scRNA-seq studies in non-model organisms. [Display omitted] • 10x Genomics Chromium technology was used to identify diverse midgut cell types based on gene expression profiles. • Midgut cell types, including stem cells and enteroblasts, were identified in an established cell line. • Genetic engineering and fluorescence imaging confirmed distinct cell types via fluorescent reporter assays. • Enriched stem cell populations were isolated using Notch promoter driven selectable marker gene. [ABSTRACT FROM AUTHOR]

Background: In recent years, gene therapy drugs have been widely marketed, and their effectiveness and potential have been confirmed. Thus, increasing their production on an industrial scale is critical. Recombinant adeno-associated viruses (rAAVs) are optimal vectors for gene therapy applications, and the baculovirus expression vector system (BEVS), which is based on Sf9 cell culture, is a common tool for rAAV production., Methods: In this work, an Sf9 cell fed-batch process was developed using shake flasks. In the laboratory-scale bioreactor, four processes were selected as the key factors when carrying out the orthogonal experiment. On the basis of the equal P/V principle and considering the problem posed by air bubbles, a pilot-scale level bioreactor process was established., Results: Here, we describe a method in which a BEVS was used to produce rAAV vectors, with the cell density increasing to 22.8 × 10 6 cells/mL and the rAAV titre increasing to 20 × 10 11 VG/mL upon adding feed material. By resolving the problems associated with high-density cell culture and air bubbles, this process was successfully scaled to a 50 L pilot-scale level., Conclusions: This successful experiment not only provides a technological basis for further scale-up but also guarantees product capacity. We hope that this development process can provide reference data for studying cell culture-based drug production., (© 2024. The Author(s).)

Biological control is an effective and sustainable method of integrated pest management. Microplitis manilae (Hymenoptera: Braconidae) is a common internal parasitoid wasp of the order Lepidoptera. To determine a suitable host species for the reproduction of parasitoids, it is essential to assess host suitability and parasitic potential of the parasitized pests. Herein, we investigated host selection and exploitation of M. manilae. We evaluated the parasitic efficacy of M. manilae in 4 pest species in the Spodoptera and Mythimna genera of the Noctuidae family. The results indicated that the parasitism rate of M. manilae on 3 species in the Spodoptera genus is higher than on Mythimna separata in the Mythimna genus, with M. manilae exhibiting a higher parasitism rate and shorter development duration on Spodoptera litura compared to other species. The parasitism rate for 1st instars hosts was 86.67 ± 0.04%, while the development duration was 14.1 ± 0.03 days. However, when parasitizing the 3rd instar of Spodoptera frugiperda, parasitoids showed a higher sex ratio, of 0.71 ± 0.05. Additionally, M. manilae had parasitic effect on M. separata, providing a new choice for its parasitism. The results identify the optimal host, which could enhance and reproduction rate and survival rate of M. manilae, thus facilitating their large-scale propagation. Understanding the parasitic effects of M. manilae on pests can further its field application, also plays a major role in promoting the development of biological control technologies and sustainable agricultural production., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

The suitability of F1 progeny insect larvae of the irradiated male parent, Spodoptera litura (Fabr.) for infective juveniles (IJs) of entomopathogenic nematodes (EPN), Steinernema thermophilum was assessed to comprehend the feasibility of combining EPNs with nuclear pest control tactic. As compared to the control, the IJs induced faster host mortality with reduced proliferation in F1 host larvae. IJs derived from F1 host larvae exhibited almost similar proliferation capacity on normal hosts as in control. Further, the molecular basis of EPNs induced mortality in F1 host larvae was evaluated. Dual stress of EPN infection and irradiation induced downregulation of the relative mRNA expression of antimicrobial genes and upregulated expression of antioxidative genes. A pronounced effect of EPNs in association with irradiation stress was apparent on host mortality. Radiation induced sterile F1 insect larvae of S. litura acted as a reasonably suitable host for EPNs and also provided the environment for developing viable EPNs for their potential use as biocontrol agents., Competing Interests: Declaration of competing interest The authors declare they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Influenza and Newcastle disease are the most important poultry diseases that cause high annual damage to poultry farms worldwide. Newcastle virus fusion (F) gene and Influenza Virus Hemagglutinin (HA) gene are capable of encoding F and HA proteins that are the main factors in creating immunity, so this study aimed to clone and express these genes in Spodoptera frugiperda (Sf9) cells using baculovirus expression system. After isolating the Newcastle and Influenza virus genome, the HA gene of influenza virus and the F gene of Newcastle virus were amplified by reverse transcriptase PCR and specific primers and then cloned into pFastBacTM Dual plasmid. A recombinant sucker with these genes was produced in the DH10Bac host cell. By transfecting Sf9 cells with recombinant bacmid, expression was assessed by SDS-PAGE, western blotting, and Bradford methods. Cloning of genes into the bacmid was successful. By transfecting the recombinant bacmid into Spodoptera frugiperda cells, 218 µg/ml of the recombinant protein was obtained in the supernatant. In addition, the presence of protein was confirmed by western blotting. The PCR products of HA and F genes showed one band of 1.7 kb size using specific primers. The pFastHA1 vector was about 7 kb in size. Two bands of about 7 kb and 1.7 kb were created by ligation of the F gene and pFastHA1 vector based on enzymatic digestion, indicating the correct ligation of F gene under the P10 promoter. This is the first report on the cloning and Co-expression of two HA and F genes using baculovirus expression system and can be a candidate for dual influenza and Newcastle vaccine. Mixtures of these recombinant proteins can be used as vaccine candidates against both avian influenza and Newcastle disease.

UDP- N -acetylglucosamine pyrophosphorylase (UAP) catalyzes the last step in the hexosamine biosynthesis pathway to directly produce UDP- N -acetylglucosamine (UDP-GlcNAc). Because UAPs play important physiological and pathological roles in organisms, they are considered potential targets for drug and pesticide development. However, the lack of efficient and selective inhibitors is a bottleneck that must be overcome. This study reports the first crystal structure of the insect UAP from Spodoptera frugiperda ( Sf UAP) in complex with UDP-GlcNAc. Sf UAP has two insect-specific structural characteristics in the active pocket, namely, a free Cys (Cys 334 ) and a Mg 2+ binding site, which differentiate it from human UAP ( Hs AGX1) and fungal UAP ( Af UAP) in terms of substrate and inhibitor binding. N -(4-Nitrophenyl)maleimide ( p NPMI) and myricetin are discovered as potent covalent and noncovalent inhibitors of Sf UAP, respectively. Moreover, myricetin can significantly reduce the level of cellular O -GlcNAcylation by inhibiting both UAP and O -GlcNAc transferase. These findings provide novel insights into the development of UAP-based drugs and pesticides.

A fundamental understanding of the underlying mechanisms involved in biological invasions is crucial to developing effective risk assessment and control measures against invasive species. The fall armyworm (FAW), Spodoptera frugiperda, is a highly invasive pest that has rapidly spread from its native Americas into much of the Eastern Hemisphere, with a highly homogeneous nuclear genetic background. However, the exact mechanism behind its rapid introduction and propagation remains unclear. Here, a systematic investigation is conducted into the population dynamics of FAW in China from 2019 to 2021 and found that FAW individuals carrying "rice" mitochondria (FAW-mR) are more prevalent (>98%) than that with "corn" mitochondria (FAW-mC) at the initial stage of the invasion and in newly-occupied non-overwintering areas. Further fitness experiments show that the two hybrid-strains of FAW exhibit different adaptions in the new environment in China, and this may have been facilitated by amino acid changes in mitochondrial-encoded proteins. FAW-mR used increases energy metabolism, faster wing-beat frequencies, and lower wing loadings to drive greater flight performance and subsequent rapid colonization of new habitats. In contrast, FAW-mC individuals adapt with more relaxed mitochondria and shuttle energetics into maternal investment, observed as faster development rate and higher fecundity. The presence of two different mitochondria types within FAW has the potential to significantly expand the range of damage and enhance competitive advantage. Overall, the study describes a novel invasion mechanism displayed by the FAW population that facilitates its expansion and establishment in new environments., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Background: Odorant-binding proteins (OBPs) in insects are key to detection and recognition of external chemical signals associated with survival. OBP7 in Spodoptera frugiperda's larval stage (SfruOBP7) may search for host plants by sensing plant volatiles, which are important sources of pest attractants and repellents. However, the atomic-level basis of binding modes remains elusive., Results: SfruOBP7 structure was constructed through homology modeling, and complex models of six plant volatiles ((E)-2-hexenol, α-pinene, (Z)-3-hexenyl acetate, lauric acid, O-cymene and 1-octanol) and SfruOBP7 were obtained through molecular docking. To study the detailed interactions between the six plant volatile molecules and SfruOBP7, we conducted three 300 ns molecular dynamics simulations for each study object. The correlation coefficients between binding free energy obtained by molecular mechanics/generalized Born surface area together with solvated interaction energy methods and experimental values are 0.90 and 0.88, respectively, showing a good correlation. By comparing binding free energy along with interaction patterns between SfruOBP7 and the six volatile molecules, hotspot residues of SfruOBP7 when binding with different volatile molecules were determined. Hydrophobic interactions stemming from van der Waals interactions play a significant role in SfruOBP7 and these plant volatile systems., Conclusion: The optimized three-dimensional structure of SfruOBP7 and its binding modes with six plant volatiles revealed their interactions, thus providing a means for estimating the binding energies of other plant volatiles. Our study will help to guide the rational design of effective and selective insect attractants. © 2024 Society of Chemical Industry., (© 2024 Society of Chemical Industry.)

Herbivorous insects such as Spodoptera litura, pose a constant threat to agricultural crops. The incompetence of contemporary pest management tools and techniques stipulates unravelling of molecular dogma, that drives pest-plant interaction. From our previous observations, we inferred that despite being a voracious polyphagous herbivore, S. litura growth and adaptability is severely hampered on maize foliage diet. In this investigation we explored further and demonstrated the impact of maize diet on the insect gut peritrophic membrane (PM, a crucial membrane involved in compartmentalizing digestive events and absorption of nutrients), its structural analysis using scanning electron microscopy (SEM) revealed damaged and perforated PM. Further, this study delves into the intricate resistance mechanism adapted by Z. mays against S. litura by conducting a comparative proteome analysis. We have detected 345 differentially abundant proteins (DAPs) at p < 0.05 and fold change ≥1. The DAPs were categorized as plant defense, secondary metabolite synthesis, redox homeostasis, cytoskeleton/cell wall biosynthesis, primary metabolism, transport and molecular processes. We remarkably report differential expression of proteolysis- and defense-related proteins that have potential to target insect gut, digestion and absorption of nutrients. Our findings contribute to a deeper understanding of the molecular dynamics governing maize resistance against S. litura. Understanding of such intricate molecular dialogues at these interfaces could provide valuable information on the arms race between plants and herbivores, it may pave the way for innovative pest management strategies. • The growth and development of S. litura is hampered on maize foliage diet. • The maize foliage diet damages insect gut peritrophic membrane (PM) and microvilli. • A comparative proteome analysis detected 168 upregulated and 177 downregulated DAPs. • Upregulation of enzymes targeting insect gut (Cys protease, chitinase) was noted. • These findings enhance understanding of maize resistance, potentially leading to novel IPM strategies. [ABSTRACT FROM AUTHOR]

Myosin-7a is an actin-based motor protein vital for auditory and visual processes. Mutations in myosin-7a lead to Usher syndrome type 1, the most common and severe form of deaf-blindness in humans. It is hypothesized that myosin-7a forms a transmembrane adhesion complex with other Usher proteins, essential for the structural-functional integrity of photoreceptor and cochlear hair cells. However, due to the challenges in obtaining pure, intact protein, the exact functional mechanisms of human myosin-7a remain elusive, with limited structural and biomechanical studies available. Recent studies have shown that mammalian myosin-7a is a multimeric motor complex consisting of a heavy chain and three types of light chains: regulatory light chain (RLC), calmodulin, and calmodulin-like protein 4 (CALML4). Unlike calmodulin, CALML4 does not bind to calcium ions. Both the calcium-sensitive, and insensitive calmodulins are critical for mammalian myosin-7a for proper fine-tuning of its mechanical properties. Here, we describe a detailed method to produce recombinant human myosin-7a holoenzyme using the MultiBac Baculovirus protein expression system. This yields milligram quantities of high-purity full-length protein, allowing for its biochemical and biophysical characterization. We further present a protocol for assessing its mechanical and motile properties using tailored in vitro motility assays and fluorescence microscopy. The availability of the intact human myosin-7a protein, along with the detailed functional characterization protocol described here, paves the way for further investigations into the molecular aspects of myosin-7a in vision and hearing.

The baculovirus expression vector system (BEVS) is a powerful tool in pharmaceutical biotechnology to infect insect cells and produce the recombinant proteins of interest. It has been well documented that optimizing the culture condition and its supplementation through designed experiments is critical for maximum protein production. In this study, besides physicochemical parameters including incubation temperature, cell count of infection, multiplicity of infection, and feeding percentage, potential supplementary factors such as cholesterol, polyamine, galactose, pluronic-F68, glucose, L-glutamine, and ZnSO4 were screened for Spodoptera frugiperda (Sf9) cell culture and expression of hemagglutinin (HA) protein of Influenza virus via Placket-Burman design and then optimized through Box-Behnken approach. The optimized conditions were then applied for scale-up culture and the expressed r-HA protein was characterized. Optimization of selected parameters via the Box-Behnken approach indicated that feed percentage, cell count, and multiplicity of infection are the main parameters affecting r-HA expression level and potency compared to the previously established culture condition. This study demonstrated the effectiveness of designing experiments to select and optimize important parameters that potentially affect Sf9 cell culture, r-HA expression, and its potency in the BEVS system., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Alizadeh et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Cotesia ruficrus presents a promising local natural enemy for controlling the invasive fall armyworm Spodoptera frugiperda in China. However, the mechanisms underlying how C. ruficrus locates its target pest remain unclear. In this study, we analyzed the expression patterns of 18 CrufOBPs across different developmental stages of C. ruficrus, and found that CrufOBP1 exhibited consistent and high expression levels in female adults. CrufOBP1 transcript was predominantly localized in sensilla placodea and sensilla trichodea on the antennae. Additionally, we confirmed the binding properties of CrufOBP1 protein to various cuticular compounds of S. frugiperda larvae. Subsequent electroantennogram and behavioral assays revealed that 1-(2-hydroxy-5-methylphenyl)-ethanone attracted female C. ruficrus, consequently increased the parasitism rate. However, upon silencing CrufOBP1, females exhibited reduced attraction towards 1-(2-hydroxy-5-methylphenyl)-ethanone, indicating the crucial role of CrufOBP1 in the chemoreception of C. ruficrus. These findings shed light on the kairomone-based mechanism employed by C. ruficrus to locate S. frugiperda larvae and hold a promise for the development of environmentally friendly pest management strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The fall armyworm (FAW) poses a significant global threat to food security, and economics. Timely detection is crucial, and this research explores innovative techniques like data analysis, remote sensing, satellite imagery, and AI with machine learning algorithms for predicting and managing outbreaks. Emphasizing the importance of community engagement and international collaboration, social network analysis (SNA) is employed to uncover collaborative networks in FAW management research. The study analyzes a decade of research, revealing trends, influential institutions, authors, and countries, providing insights for efficient FAW management strategies. The research highlights a growing interest in Spodoptera frugiperda (Smith and Abbott 1797) research, focusing on biological control, chemical insecticides, plant extracts, and pest resistance. Co-Citation analysis identifies key research concepts, while collaboration analysis emphasizes the contributions of actors and institutions, such as China, the USA, and Brazil, with international collaboration playing a vital role. Current research trends involve evolving resistance, insecticidal protein gene discovery, and bio-control investigations. Leveraging insights from collaborative networks is essential for formulating effective strategies to manage fall armyworm and ensure global food security. This comprehensive analysis serves as a valuable resource for researchers and stakeholders, guiding efforts to combat this pervasive agricultural pest., (© 2024. Sociedade Entomológica do Brasil.)

In this work, the implications of AAV9 capsid design and column reuse on AAV9 vector product quality were assessed with POROS CaptureSelect (PCS) AAVX and AAV9 resins using sf9 insect cell-derived model AAV9 vectors with varying viral protein (VP) ratios. Chromatographic experiments with purified drug substance AAV9 model feeds indicated consistent vector elution profiles, independent of adeno-associated virus (AAV) VP ratio, or cycle number. In contrast, the presence of process impurities in the clarified lysate feeds resulted in clear changes in the elution patterns. This included increased aggregate content in the vector eluates over multiple cycles as well as clear differences in the performance of these affinity resin systems. The AAV9-serotype specific PCS AAV9 column, with lower vector elution pH, resulted in higher aggregate content over multiple cycles as compared to the serotype-independent PCS AAVX column. Further, the results with vectors of varying VP ratio indicated that while one vector type eluate displayed higher aggregation in both affinity columns over column reuse, the eluate with the other vector type did not exhibit changes in the aggregation profile. Interestingly, vector aggregates in the affinity eluates also contained double-stranded DNA impurities and histone proteins, with similar trends to the aggregate levels. This behavior upon column reuse indicates that these host cell impurities are likely carried over to subsequent runs due to incomplete clean-in-place (CIP). These results indicate that feed impurities, affinity resin characteristics, elution pH, column CIP, and vector stability can impact the reusability of AAV affinity columns and product quality., (© 2023 Wiley Periodicals LLC.)

Eicosanoids mediate insect immune responses and synthesized by the catalytic activity of phospholipase A2 (PLA2). A uniquely encoded secretory PLA2 (sPLA2) is associated with immune responses of a lepidopteran insect, Spodoptera exigua. Its deletion mutant was generated using a CRISPR/Cas9 genome editing technology. Both wild and mutant lines were then immune-challenged, and the resulting transcripts were compared with their naïve transcripts by RNASeq using the Illumina-HiSeq platform. In total, 12,878 unigenes were further analyzed by differentially expressed gene tools. Over 69% of the expressed genes in S. exigua larvae are modulated in their expression levels by eicosanoids, recorded from CRISPR/Cas9 mutagenesis against an eicosanoid-synthetic gene, Se-sPLA2. Further, about 36% of the immune-associated genes are controlled by the eicosanoids in S. exigua. Indeed, the deletion mutant suffered significant immunosuppression in both cellular and humoral responses in response to bacterial challenge as well as severely reduced developmental and reproductive potentials., Competing Interests: The authors have declared that no competing interests exist., (Copyright: This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.)

Neutrophil proteinase 3 (PR3) is an important drug target for inflammatory lung diseases such as chronic obstructive pulmonary disease and cystic fibrosis. Drug discovery efforts targeting PR3 require active enzyme for in vitro characterization, such as inhibitor screening, enzymatic assays, and structural studies. Recombinant expression of active PR3 overcomes the need for enzyme supplies from human blood and in addition allows studies on the influence of mutations on enzyme activity and ligand binding. Here, we report the expression of recombinant PR3 (rPR3) using a baculovirus expression system. The purification and activation process described resulted in highly pure and active PR3. The activity of rPR3 in the presence of commercially available inhibitors was compared with human PR3 by using a fluorescence-based enzymatic assay. Purified rPR3 had comparable activity to the native human enzyme, thus being a suitable alternative for enzymatic studies in vitro. Further, we established a surface plasmon resonance-based assay to determine binding affinities and kinetics of PR3 ligands. These methods provide valuable tools for early drug discovery aiming towards treatment of lung inflammation., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Khorsand et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Our laboratory previously discovered a novel rhabdovirus in the Spodoptera frugiperda Sf9 insect cell line that was designated as Sf-rhabdovirus. Using limiting dilution, this cell line was found to be a mixed population of cells infected by Sf-rhabdovirus variants containing either the full length X accessory gene with a 3.7 kb internal duplication (designated as Sf-rhabdovirus X +3.7 ) or lacking the duplication and part of the X gene (designated as Sf-rhabdovirus X - ), and cells that were negative for Sf-rhabdovirus. In this paper, we found that the Sf-rhabdovirus negative cell clones had sub-populations with different susceptibilities to the replication of Sf-rhabdovirus X +3.7 and X - variants: cell clone Sf9-13F12 was more sensitive to replication by both virus variants compared to Sf9-3003; moreover, Sf9-3003 showed more resistance to X +3.7 replication than to X - replication. RNA-Seq analysis indicated significant differentially expressed genes in the Sf9-13F12 and Sf9-3003 cell clones further supporting that distinct sub-populations of virus-negative cells co-exist in the parent Sf9 cell line., Competing Interests: Declaration of competing interest All authors declare no competing interests., (Published by Elsevier Inc.)

To extract any adaptive benefit, the circadian clock needs to be synchronized to the 24-h day-night cycles. We have investigated if it is a general property of the brain's circadian clock to recognize social interactions as external time givers. Sociosexual interactions with the opposite sex are universal, prevalent even in the lives of solitary animals. The solitary adult life of the Spodoptera littoralis moth is singularly dedicated to sex, offering an ideal context for exploring the impact of sociosexual cues on circadian timekeeping. We have identified specific olfactory cues responsible for social entrainment, revealing a surprisingly strong influence of pheromone-mediated remote sociosexual interactions on circadian rhythms. Males' free-running rhythms are induced and synchronized by the sex pheromone that the female releases in a rhythmic fashion, highlighting a hierarchical relation between the female and male circadian oscillators. Even a single pulse of the sex pheromone altered clock gene expression in the male brain, surpassing the effect of light on the clock. Our finding of a daytime-dependent, lasting impact of pheromone on male's courtship efficacy indicates that circadian timing in moths is a trait under sexual selection. We have identified specific components of the sex-pheromone blend that lack mate-attractive property but have powerful circadian effects, providing rationale for their continued retention by the female. We show that such volatiles, when shared across sympatric moth species, can trigger communal synchronization. Our results suggest that the sex pheromone released by female moths entrains males' behavioral activity rhythm to ensure synchronized timing of mating. [Display omitted] • Females' sex pheromone enhances and synchronizes males' activity rhythms • Pheromone-guided social interaction resets the molecular oscillators in the brain • Social entrainment maximizes male mating efficacy • Communal synchronization in sympatric species without heterospecific mating Ghosh et al. report a strong resetting potential of remote sociosexual cues in the solitary Spodoptera moth where the female circadian clock is poised to entrain and support the male clock using multiple sex pheromone components regardless of their mating-modulating role. Circadian communication can extend to a community of sympatric species. [ABSTRACT FROM AUTHOR]

Chemosensory proteins (CSPs) constitute a class of olfactory proteins localized in insect sensory organs that serve a crucial function in decoding external chemical stimuli. This study aims to elucidate the involvement of CrufCSP3 in olfactory perception within the context of Cotesia ruficrus , an indigenous endoparasitoid targeting the invasive pest Spodoptera frugiperda . Through fluorescence-competitive binding assays and site-directed mutagenesis, we pinpointed four amino acids as pivotal residues involved in the interaction between CrufCSP3 and five host-related compounds. Subsequent RNA interference experiments targeting CrufCSP3 unveiled a reduced sensitivity to specific host-related compounds and a decline in the parasitism rate of the FAW larvae. These findings unequivocally indicate the essential role of CrufCSP3 in the chemoreception process of C. ruficrus . Consequently, our study not only sheds light on the functional importance of CSPs in parasitic wasp behavior but also contributes to the development of eco-friendly and efficacious wasp behavior modifiers for effectively mitigating pest population surges.

Insect pests cause immense agronomic losses worldwide. One of the most destructive of major crops is the Fall Armyworm (Spodoptera frugiperda, FAW). The ability to migrate long distances, a prodigious appetite, and a demonstrated ability to develop resistance to insecticides, make it a difficult target to control. Insecticidal proteins, for example those produced by the bacterium Bacillus thuringiensis, are among the safest and most effective insect control agents. Genetically modified (GM) crops expressing such proteins are a key part of a successful integrated pest management (IPM) program for FAW. However, due to the development of populations resistant to commercialized GM products, new GM traits are desperately needed. Herein, we describe a further characterization of the newly engineered trait protein eCry1Gb.1Ig. Similar to other well characterized Cry proteins, eCry1Gb.1Ig is shown to bind FAW midgut cells and induce cell-death. Binding competition assays using trait proteins from other FAW-active events show a lack of competition when binding FAW brush border membrane vesicles (BBMVs) and when utilizing non-pore-forming versions as competitors in in vivo bioassays. Similarly, insect cell lines expressing SfABCC2 and SfABCC3 (well characterized receptors of existing commercial Cry proteins) are insensitive to eCry1Gb.1Ig. These findings are consistent with results from our previous work showing that eCry1Gb.1Ig is effective in controlling insects with resistance to existing traits. This underscores the value of eCry1Gb.1Ig as a new GM trait protein with a unique site-of-action and its potential positive impact to global food production., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Upon immune challenge, recognition signals trigger insect immunity to remove the pathogens through cellular and humoral responses. Various immune mediators propagate the immune signals to nearby tissues, in which polyunsaturated fatty acid (PUFA) derivatives play crucial roles. However, little was known on how the insects terminate the activated immune responses after pathogen neutralization. Interestingly, C20 PUFA was detected at the early infection stage and later C18 PUFAs were induced in a lepidopteran insect, Spodoptera exigua. This study showed the role of epoxyoctadecamonoenoic acids (EpOMEs) in the immune resolution at the late infection stage to quench the excessive and unnecessary immune responses. In contrast, dihydroxy-octadecamonoenoates (DiHOMEs) were the hydrolyzed and inactive forms of EpOMEs. The hydrolysis is catalyzed by soluble epoxide hydrolase (sEH). Inhibitors specific to sEH mimicked the immunosuppression induced by EpOMEs. Furthermore, the inhibitor treatments significantly enhanced the bacterial virulence of Bacillus thuringiensis against S. exigua. This study proposes a negative control of the immune responses using EpOME/DiHOME in insects., Competing Interests: Declaration of competing interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Production of value-added products from waste anaerobic digestate is economically and environmentally important for sustainable development of industrial process and products. In this study halophilic microalgae, Chlorella vulgaris 92001, Chlorella vulgaris 50291, Chlorella vulgaris 10241 and Tetraselmis indica, were initially screened for lutein production using synthetic dairy digestate (DD), municipal digestate (MD) and poultry digestate (PD) as no-cost substrates. Screening and optimization of parameters, such as dilution, pH, MgCl 2 , NaCl, NaHCO 3 and inoculum concentration for maximum lutein production were further performed employing statistically designed Plackett-Burman and response surface methodology. Cultivation of C. vulgaris 92001 in a split column photobioreactor under optimum culture condition showed increase in lutein production by 2.36-fold in batch mode. The influence of different hydraulic retention time (HRT) values of 150, 130, 100 and 90 h on lutein production was evaluated in continuous mode with the split column photobioreactor. Lutein produced using the synthetic poultry digestate showed good potential biopesticide activity against Spodoptera litura (fall armyworm). Overall, this study demonstrated bioprocess development to produce lutein using synthetic anaerobic digestate from marine algae and its potential application as a biopesticide., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Insect-plant interactions are among importantly ecological processes, and rapid environmental changes such as temperature and resource fluctuations can disrupt long-standing insect-plant interactions. While individual impacts of climate warming, atmospheric nitrogen (N) deposition, and plant provenance on insect-plant interactions are well studied, their joint effects on insect-plant interactions are less explored in ecologically realistic settings. To this end, we performed five experiments with native and invasive Solidago canadensis populations from home and introduced ranges and two insect herbivores (leaf-chewing Spodoptera litura and sap-sucking Corythucha marmorata) in the context of climate warming and N deposition. We determined leaf defensive traits, feeding preference, and insect growth and development, and quantified the possible associations among climate change, host-plant traits, and insect performance with structural equation modeling. First, native S. canadensis populations experienced higher damage by S. litura but lower damage by C. marmorata than invasive S. canadensis populations in the ambient environment. Second, warming decreased the leaf consumption, growth, and survival of S. litura on native S. canadensis populations, but did not affect these traits on invasive S. canadensis populations; warming increased the number of C. marmorata on native S. canadensis populations via direct facilitation, but decreased that on invasive S. canadensis populations via indirect suppression. Third, N addition enhanced the survival of S. litura on native S. canadensis populations, and its feeding preference and leaf consumption on invasive S. canadensis populations. Finally, warming plus N addition exhibited non-additive effects on insect-plant interactions. Based on these results, we tentatively conclude that climate warming could have contrasting effects on insect-plant interactions depending on host-plant provenance and that the effects of atmospheric N deposition on insects might be relatively weak compared to climate warming. Future studies should focus on the molecular mechanisms underlying these different patterns., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Wei-Ming He reports financial support was provided by Ministry of Science and Technology of the People's Republic of China. Wei-Ming He reports financial support was provided by Hebei Agricultural University., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Trehalases (TREs) are pivotal enzymes involved in insect development and reproduction, making them prime targets for pest control. We investigated the inhibitory effect of three thiazolidinones with piperine skeletons (6a, 7b, and 7e) on TRE activity and assessed their impact on the growth and development of the fall armyworm (FAW), Spodoptera frugiperda . The compounds were injected into FAW larvae, while the control group was treated with 2% DMSO solvent. All three compounds effectively inhibited TRE activity, resulting in a significant extension of the pupal development stage. Moreover, the treated larvae exhibited significantly decreased survival rates and a higher incidence of abnormal phenotypes related to growth and development compared to the control group. These results suggest that these TRE inhibitors affect the molting of larvae by regulating the chitin metabolism pathway, ultimately reducing their survival rates. Consequently, these compounds hold potential as environmentally friendly insecticides.

Diversity analysis using molecular markers serves as a powerful tool in unravelling the intricacies of inclusivity within various populations and is an initial step in the assessment of populations and the development of inbred lines for host plant resistance in maize. This study was conducted to assess the genetic diversity and population structure of 242 newly developed S3 inbred lines using 3,305 single nucleotide polymorphism (SNP) markers and to also assess the level of homozygosity achieved in each of the inbred lines. A total of 1,184 SNP markers were found highly informative, with a mean polymorphic information content (PIC) of 0.23. Gene diversity was high among the inbred lines, ranging from 0.04 to 0.50, with an average of 0.27. The residual heterozygosity of the 242 S3 inbred lines averaged 8.8%, indicating moderately low heterozygosity levels among the inbred lines. Eighty-four percent of the 58,322 pairwise kinship coefficients among the inbred lines were near zero (0.00-0.05), with only 0.3% of them above 0.50. These results revealed that many of the inbred lines were distantly related, but none were redundant, suggesting each inbred line had a unique genetic makeup with great potential to provide novel alleles for maize improvement. The admixture-based structure analysis, principal coordinate analysis, and neighbour-joining clustering were concordant in dividing the 242 inbred lines into three subgroups based on the pedigree and selection history of the inbred lines. These findings could guide the effective use of the newly developed inbred lines and their evaluation in quantitative genetics and molecular studies to identify candidate lines for breeding locally adapted fall armyworm tolerant varieties in Ghana and other countries in West and Central Africa., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Adu et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: The beet armyworm, Spodoptera exigua (Hübner), is an important agricultural pest worldwide that has caused serious economic losses in the main crop-producing areas of China. To effectively monitor and control this pest, it is crucial to investigate its population dynamics and seasonal migration patterns in northern China., Methods: In this study, we monitored the population dynamics of S. exigua using sex pheromone traps in Shenyang, Liaoning Province from 2012 to 2022, combining these data with amigration trajectory simulation approach and synoptic weather analysis., Results: There were significant interannual and seasonal variations in the capture number of S. exigua, and the total number of S. exigua exceeded 2,000 individuals in 2018 and 2020. The highest and lowest numbers of S. exigua were trapped in September and May, accounting for 34.65% ± 6.81% and 0.11% ± 0.04% of the annual totals, respectively. The average occurrence period was 140.9 ± 9.34 days during 2012-2022. In addition, the biomass of S. exigua also increased significantly during these years. The simulated seasonal migration trajectories also revealed varying source regions in different months, primarily originated from Northeast China and East China. These unique insights into the migration patterns of S. exigua will contribute to a deeper understanding of its occurrence in northern China and provide a theoretical basis for regional monitoring, early warning, and the development of effective management strategies for long-range migratory pests., Competing Interests: The authors declare there are no competing interests., (©2024 Ma et al.)