Nymphal Stages Research Articles

Another new species of the genus Habrophlebia Eaton, 1881 (Ephemeroptera, Leptophlebiidae) from the Maghreb.

A new species belonging to the genus Habrophlebia Eaton, 1881 is described at the nymphal stage from the Rif Mountains of Morocco. This species presents unique features, such as the chorionic arrangement of the egg and the ornamentation of the posterior margin of abdominal tergites. It is compared to all west European Habrophlebia species and a table with discriminating characters is given. A phylogenetic reconstruction based on COI sequences fully supports the hypothesis of a new species in the Rif Mountains, with possible further distribution in southern Spain.

Dynamic Gut Microbiota of Apolygus lucorum Across Different Life Stages Reveals Potential Pathogenic Bacteria for Facilitating the Pest Management.

Insect's gut microbiota has diverse effects on their fitness, and a comprehensive understanding of gut microbiota functions requires analyzing its diversity. Apolygus lucorum is a highly destructive pest that threatens many economically important crops in China. This study investigated the gut microbiota of A. lucorum across its life cycle using both culture-dependent and culture-independent methods. A total of 87 gut bacterial isolates were identified, belonging to 4 phyla, 27 families, and 45 genera, while Miseq sequencing detected 91 amplicon sequence variants (ASVs) assigned to 5 phyla, 28 families, and 39 genera. Proteobacteria and Firmicutes were the predominant phyla, with Staphylococcus and Serratia as the major genera. There were significant differences in the relative abundance of these genera between the nymph and adult stages. Staphylococcus was significantly more abundant in nymphs than it in adults, while Serratia was significantly more abundant in sexually mature adults than in other developmental stages. Notably, Serratia is a common opportunistic pathogen in many insects. Injecting the gut-dominant isolate Serratia marcescens verified its high pathogenicity. Additionally, immune indicators of the bug at different developmental stages supported the hypothesis that Serratia is a pathogen of A. lucorum. This study provides a foundation for understanding the role of gut bacteria in the life history of A. lucorum and developing new pest control strategies based on microbes.

Study of Thermal Requirements for the Development of Two-Spotted Mites Tetranychus urticae Koch (Acariformes: Tetranychidae), Reared on Castor Leaves (Ricinus communis L.) Under Laboratory Conditions

The two-spotted spider mite Tetranychus urticae Koch (Acariformes: Tetranychidae) is an important pest affecting several important oil crops in Iraq. The aim of this study was to determine the minimum temperature and calculate the necessary heat units for the time of development of the duration of these mites stages. The application was carried out in incubators with different temperatures (10, 15, 20, 25, 30, 35 and 40 +2 °C), relative humidity (50-60 +5%) and light: 8: 16 hours dark period on the lower surface of the grown castor leaves. newly. The results showed that the development time of the egg incubation, the larval stage, the first nymphal(protonymph) stage (active + quiescence), and the second nymphal (deutonymph) stage (active + quiescence) at temperatures 15, 20, 25, 30, and 35 °C. It decreased gradually with increasing temperature. Moreover, the egg incubation period was 8.533 and 2.067 days, the larval stage (active + quiescence) 5.821 and 1.298 days, the first nymph (protonymph) (active + quiescence) 5.521 and 1.309 days, and the second nymph (deutonymph) (active + quiescence) 5.417 and 1.150. days to the effect of 15 and 35 degrees Celsius. In addition, the development time from egg to adult was 24.972 and 5.833 days at 15 and 35 °C, respectively. The temperature threshold was 9.763, 10.693, 9.543, 10.314, and 9.957 degrees Celsius, respectively. Finally, the accumulated heat units required for the growth time of each mite cycle differed according to the different temperature threshold and growth time and the mite could not grow and develop at 10 and 40 °C.

A Note on Leaf Gall on Alstonia scholaris (Saptaparni) tree due to Infestation of Pauropsylla tuberculata (Gall Insect)

Alstonia scholaris is a perennial evergreen tree of family Apocynaceae and one of the graceful ornamental and medicinal plants. In general, this tree suffers the problem, that is, gall formation on a leaf. Most probably, it is caused by leaf gall insects (Pauropsylla tuberculata) belonging to order Hemiptera and is commonly known as jumping lice. The insect has five nymphal stages and forms the gall by sucking the plant sap. It lacks the pupal stage. Such a heavy attack by this insect affects the rate of photosynthesis and overall growth of plants. This brief note focuses on the development and formation of galls by Pauropsylla tuberculata and different nymphal stages of it on A. scholaris leaves.. KEYWORDS :Alstonia scholaris, Hemiptera, Leaf Gall Insects, Pauropsylla tuberculate

Composition and diversity of the gut microbiota across different life stages of American cockroach (Periplaneta americana).

Periplaneta americana, one of the most widely distributed insects all over the world, can survive and reproduce in harsh environment which may be closely related to the critical roles of intestinal microorganisms in its multiple physiological functions. However, the composition and structure of gut microbiota throughout different life stages and its effects on the strong resilient and environmental adaptability of P. americana remain unclear. In this study, the gut microbiota across life stages including ootheca (embryos), nymph and adult of P. americana were investigated by 16S rRNA high-throughput sequencing. Multivariate statistical analysis showed the richness and diversity of bacterial communities were significantly different among ootheca, nymph and adult stage of P. americana. Taxonomic analysis showed Blattabacterium was the dominant genus in bacterial community of ootheca while the nutrient absorption-related genera including Christensenellaceae and Ruminococcaceae showed high relative abundance in nymph samples. Moreover, functional prediction analysis showed the metabolic categories in ootheca might have more influence on the basic life activities of the host than improved production and viability, while it was more associated to the society activities, reproduction and development of host in nymph and adult. It was suggested that the gut microbiota in each life stage might meet the requirements for environmental adaptability and survival of P. americana via transforming the composition and structure with specific metabolic capabilities. Overall, these results provided a novel sight to better understand the strong vitality and adaptability throughout life stages of P. americana.

Control of sweet potato whitefly (Bemisia tabaci) using entomopathogenic fungi under optimal and suboptimal relative humidity conditions.

Sweet potato whitefly (Bemisia tabaci) is one of the most destructive pests to an extensive range of crops and vegetables. Pesticide-dependent management programs have led to severe health problems, including pesticide poisoning and cancer in human beings, as well as pesticide resistance in insect pests. Entomopathogenic fungi (EPF) are considered safe and highly effective against many pests. Therefore, identifying the pathogenicity and virulence of EPFs against Bemisia tabaci is a valuable addition to the management of their infestations. In this study, we investigated the efficacy of conidia suspensions of Aschersonia aleyrodis, Isaria fumosorosea, Beauveria bassiana, and Akanthomyces muscarius (= Lecanicillium muscarium) against nymphal stages of Bemisia tabaci in cucumber seedlings under both optimal and suboptimal conditions. All of the EPFs demonstrated significant ovicidal effects, with the highest cumulative mortalities observed in Aschersonia aleyrodis (96.46%) and I. fumosorosea-treated (94.60%) seedlings against host eggs and crawlers. Similarly, in the L4-instars experiment, Aschersonia aleyrodis and I. fumosorosea were the most efficient, resulting in cumulative mortalities of 94.82% and 94.75%, respectively. However, Bemisia tabaci cumulative mortalities on seedlings treated with Akanthomyces muscarius (78.36%) and Beauveria bassiana (85.90%) were also significantly different from untreated seedlings (7.10%). Under suboptimal relative humidity (RH) conditions (≤ 45% RH), Aschersonia aleyrodis exhibited greater tolerance to harsh conditions, causing a significantly higher infection rate in L1-L2 nymphs (~92%) compared to the approximately 32% infected young nymphs observed in I. fumosorosea-treated seedlings. All the selected EPF were more effective against the young nymphal instars. Our results also highlight the efficacy of Aschersonia aleyrodis under suboptimal conditions. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Functional response of Neoseiulus californicus (Acari: Phytoseiidae) to Tetranychus urticae (Acari: Tetranychidae) at different temperatures.

Environmental factors like temperature have a great impact on the predation potential of biological control agents. In the present study, the functional response of the predatory mite Neoseiulus californicus (Acari: Phytoseiidae) to the pest mite Tetranychus urticae (Acari: Tetranychidae) at moderate to high temperatures under laboratory conditions was determined. The study aimed to understand the prey-predator interaction under different temperatures and prey densities. Five constant temperatures (24 °C, 27 °C, 30 °C, 33 °C, and 36 °C), and thirteen prey densities (4, 5, 8, 10, 12, 15, 16, 20, 24, 25, 30, 32, and 40) of each stage (adult, nymph, larvae, and egg stage) were employed in the experiment. Observations were made 24 h after the start of each experiment. Results revealed that the predatory mites showed type II functional response to adult females of T. urticae, whereas type I to other stages (nymphs, larvae, and eggs) of T. urticae. The predation capability of adult predatory mites on T. urticae was significant at 24-36 °C. The instantaneous attack rate (a) of N. californicus increased and the handling time (Th) decreased with an increase in temperature. The maximum attack rate was recorded at 36 °C (1.28) for the egg stage. The longest handling time was (0.78) for the larval stage of T. urticae at 30 °C. Daily consumption increased with increasing prey density. Maximum daily consumption was observed at 33 °C (30.00) at the prey density of 40. Searching efficiency decreased with the increase in prey density but was found to increase with the rise in temperature. N. californicus was found to be voracious on the larval and egg stages. Conclusively, the incorporation of N. californicus at earlier stages (larvae and eggs) of T. urticae would be beneficial under warm conditions because managing a pest at its initial stage will save the crop from major losses. The results presented in this study at various temperatures will be helpful in different areas with different temperature extremes. The results of the functional response can also be applied to mass rearing, quality testing, and integrated pest management programmes.

The migratory locust (Locusta migratoria) as a potential source of protein and biopolymer compounds in the future

Abstract. Kleden YL, Mukkun L, Ndapamuri MH, Pamatana F. 2023. The migratory locust (Locusta migratoria Meyen) as a potential source of protein and biopolymer compounds in the future. Biodiversitas 24: 5979-5987. The migratory locust Locusta migratoria Linnaeus 1758, is an edible insect posing significant challenges to the agricultural industry in Indonesia, particularly in East Nusa Tenggara (ENT) Province. However, apart from the status of the migratory locust as a highly destructive insect pest, it has great potential as a source of protein, amino acids, and other bioactive compounds. This study aimed to determine the nutritional and other bioactive characteristics of locusts. Proximate analysis was performed using SNI 01-2891-1992 to identify protein, fat, ash, carbohydrates, and energy. The amino acid analysis was conducted using Ultra Performance Liquid Chromatography (UPLC). The chitin from the nymph and imago stages of the locust was obtained through a process including demineralization and deproteinization. Subsequently, the chitin was subjected to deacetylation in order to obtain chitosan. Proximate content analysis shows that locust has promising potential as a source of nutrients in order to address the nutritional problems of the population that are still a problem in Indonesia including in ENT Province. The protein content of locust ranged from 63.72 to 75.26% dry weight. These contents are close to those of egg protein (83%), beef protein (85%), and even most plant proteins, like soybean (81%). The imago stage exhibited the highest total amino acid content, measuring 411.41 mg/100 g, with essential amino acids such as lysine, isoleucine, leucine, valine, phenylalanine, threonine, histidine, and tryptophae. Imago contains chitin from 8.79 to 12.05% dry weight and chitosan from 59.3% to 71.26% by weight of chitin. The study suggests that locusts can be an alternative source of nutrition to dial with stunting in term of their availability of protein and amino acid. Additionally, chitin and chitosan in migratory locusts are promising nutrient sources for agriculture and health applications.

Two new species of the genus Ologamasus (Ologamasidae) from apple orchards in southern Brazil.

This paper describes two new species of the genus Ologamasus (Acari: Ologamasidae), namely Ologamasus margaridae n. sp. and Ologamasus tuberculatus n. sp., based on females, males and nymphal stages collected in apple orchards (Malus domestica Borkh.) in southern Brazil. Ologamasus tuberculatus has a distinctive pair of large pores inserted on protuberances on the dorsal shield.

Acaricidal effect of crude aqueous extract of Nicotiana tabacum along with turmeric and Annona leaf extract on cattle ticks

The ectoparasites produces severe economic and production loss in farm animal’s through tick bites, sucking of blood, tick worry, tick toxicosis, tick paralysis and transmission of haemoprotozoan diseases. Ticks developed resistance against chemical acaricides and also the residues of chemical acaricide producing environmental pollution. The herbal based acaricide used as biocontrol agent for protecting environment particularly hilly area. As per indigenous technical knowledge records, the Nicotiana tabacum was a traditional control remedy for control of ectoparasites in India. In vitro acaricidal efficacy of crude aqueous leaf extract of Nicotiana tabacum along with neem and turmeric followed by Annona leaves on immature and adult stages of Rhipicephalus sp. was carried out at different concentrations of with different time interval. These extract combo had a significant effect on the mortality of nymphal and adult stages of ticks. The 70%, 80% and 90% mortality of Nymphal and adult stages of ticks at 24-36 hours post treatment with 40%, 50% 70% concentration of herbal extract in invitro assay. The mortality rates of ticks increased with the increasing the extract concentrations both in vivo and in vitro. Nicotiana tabacum causes paralysis of ticks and leads to detachment from the body of animal and concluded that Nicotiana tabacum along with turmeric and annona extract is effective biocontrol agent for controlling ectoparasites without any environmental pollution and harmful side effect in animal health.

Risk of resistance and the metabolic resistance mechanism of Laodelphax striatellus (Fallén) to cyantraniliprole

Cyantraniliprole is a highly effective diamide insecticide used to control of Laodelphax striatellus (Fallén). This study aimed to assess the insecticide resistance risk of L. striatellus and its metabolic resistance mechanisms. After 25 continuous generations of selection, the resistance of L. striatellus to cyantraniliprole increased by 17.14-fold. The realistic heritability of resistance was 0.0751. After successive rearing for five generations without exposure to insecticides, the resistance ratio for the resistant strain of L. striatellus decreased by 3.47-fold, and the average resistance decline rate per generation was 0.0266. Cyantraniliprole-resistant strains did not exhibit cross-resistance to triflumezopyrim, pymetrozine, flonicamid, sulfoxaflor, dinotefuran, clothianidin, thiamethoxam, nitenpyram, or imidacloprid. Compared to those of the sensitive strain, the 2nd, 3rd, and 4th instars, nymphal stage durations, total preoviposition period, and average generation time of the resistant strain were markedly reduced. Furthermore, the activity of cytochrome P450 monooxygenase (P450) and carboxylesterase (CarE) were markedly increased. The upregulation of CYP419A1v2 expression was most evident among the P450 genes, with a 6.10-fold increase relative to that in the sensitive strain. The CarE gene LsCarE5 was significantly upregulated by 1.94-fold compared with that in the sensitive strain. With the continuous use of cyantraniliprole, L. striatellus may develop resistance to this insecticide. This resistance may be related to the increase in metabolic enzyme activities regulated by the overexpression of P450 and CarE genes.

Ontogeny of color development in two green-brown polymorphic grasshopper species.

Many insects, including several orthopterans, undergo dramatic changes in body coloration during ontogeny. This variation is particularly intriguing in gomphocerine grasshoppers, where the green and brown morphs appear to be genetically determined (Schielzeth & Dieker, 2020, BMC Evolutionary Biology, 20, 63; Winter etal., 2021, Heredity, 127, 66). A better understanding of how these color morphs develop during ontogeny can provide valuable insights into the evolution and ecology of such a widespread color polymorphism. Here, we focus on the color development of two green-brown polymorphic species, the club-legged grasshopper Gomphocerus sibiricus and the steppe grasshopper Chorthippus dorsatus. By following the color development of individuals from hatching to adulthood, we found that color morph differences begin to develop during the second nymphal stage, are clearly defined by the third nymphal stage, and remain stable throughout the life of an individual. Interestingly, we also observed that shed skins of late nymphal stages are identifiable by color morphs based on their yellowish coloration, rather than the green that marks green body parts. Furthermore, by assessing how these colors are perceived by different visual systems, we found that certain potential predators can chromatically discriminate between morphs, while others may not. These results suggest that the putative genes controlling color morph are active during the early stages of ontogeny, and that green color is likely composed of two components, one present in the cuticle and one not. In addition, the effectiveness of camouflage appears to vary depending on the specific predator involved.

Bird-of-paradise, thorn apple and maize pollens are promising alternative diets for the long-term rearing of predatory mite Amblyseius swirskii (Acari: Phytoseiidae)

Pollen grains can provide important nutrients for reproduction of different predators such as phytoseiid mites. Since mass rearing of phytoseiid predatory mites may be facilitated by feeding on alternative diets, the current study evaluated the utility of plant pollen as diet for mass rearing of the predatory mite Amblyseius swirskii Athias-Henriot, which is a commercially available biocontrol agent of phytophagous mites and insects. Demographic parameters of A. swirskii fed on pollens of bird-of-paradise (Caesalpinia gilliesii), thorn apple (Datura stramonium), and maize (Zea mays) were determined over 10 continuous generations. In addition, the pollens of common hibiscus (Hibiscus syriacus), and velvetleaf (Abutilon theophrasti) were assessed, but the predatory mite was unable to reach adulthood when fed on these pollens, and most of them died in nymphal stages. This study also evaluated the preying ability of A. swirskii on the natural prey Tetranychus urticae Koch before and after 10 generations. All experiments were conducted in the laboratory under controlled conditions of 25±1°C, 60±5% RH, and a photoperiod of 16:8 (L: D) h. According to the life table parameters, the pollen grains of bird-of-paradise, followed by maize and thorn apple, were shown to be promising diets for the long-term rearing of A. swirskii. Furthermore, the study found that A. swirskii reared on bird-of-paradise pollen had a high predation capability, with a mean of 677 prey per generation after 10 generations. Overall, it is concluded that while bird-of-paradise pollen was the most suitable alternative diet for the predatory mite, both maize and thorn apple pollen grains were also found to be promising diets for A. swirskii. These diets can be used for mass rearing of this predatory mite.

Development and formation of wing cuticle based on transcriptomic analysis in Locusta migratoria during metamorphosis

Wings are an important flight organ of insects. Wing development is a complex process controlled by a series of genes. The flightless wing pad transforms into a mature wing with the function of migratory flight during the nymph-to-adult metamorphosis. However, the mechanism of wing morphogenesis in locusts is still unclear. This study analyzed the microstructures of the locust wing pads at pre-eclosion and the wings after eclosion and performed the comparative transcriptome analysis. RNA-seq identified 25,334 unigenes and 3,430 differentially expressed genes (DEGs) (1,907 up-regulated and 1,523 down-regulated). The DEGs mainly included cuticle development (LmACPs), chitin metabolism (LmIdgf4), lipid metabolism-related genes, cell adhesion (Integrin), zinc finger transcription factors (LmSalm, LmZF593 and LmZF521), and others. Functional analysis based on RNA interference and hematoxylin and eosin (H&E) staining showed that the three genes encoded zinc finger transcription factors are essential for forming wing cuticle and maintaining morphology in Locusta migratoria. Finally, the study found that the LmSalm regulates the expression of LmACPs in the wing pads at pre-eclosion, and LmZF593 and LmZF521 regulate the expression of LmIntegrin/LmIdgf4/LmHMT420 in the wings after eclosion. This study revealed that the molecular regulatory axis controls wing morphology in nymphal and adult stages of locusts, offering a theoretical basis for the study of wing development mechanisms in hemimetabolous insects.

Efficacy of ethyl-4-bromophenyl carbamate on different Rhipicephalus microplus stages implanted in cattle.

The effect of ethyl-4-bromophenyl carbamate on different Rhipicephalus microplus stages implanted in cattle was evaluated using the pen test with infestation chambers. Twelve steers were distributed into four groups (n = 3), each with four chambers (12 chambers per group), where approximately 1,000 R. microplus larvae were placed in each chamber. The chambers of the first group were sprayed with a solution of ethyl-4-bromophenyl carbamate (0.668mg/mL) on day 2 post-infestation (PI) (exposed larvae). The chambers of the second group were sprayed with the same solution on day 8 PI (exposed nymphs), and the chambers of the third group were sprayed on day 16 PI (exposed adults) with the same solution. The chambers of the fourth group were used as controls. The percentages of engorged females, egg laying, egg production and egg hatching were evaluated in all groups. The percentage of cumulative reduction of hatched larvae was 98.3, 96.1 and 94.4% when larvae, nymph and adult stages were treated, respectively. The average cumulative reduction of hatched larvae, considering the three treated stages, was 96.3%, whereby the reproductive potential of this tick was drastically reduced. In conclusion, ethyl-4-bromophenyl carbamate acted as an ixodicide (lethal effect) when larval stages were sprayed and as a growth regulator when nymphal and adult stages were sprayed. The sum of these effects had a direct impact on the efficacy of the product in the pen test, and future studies will indicate the potential use of this product for tick control.

Life Cycle and Damage Patterns of Tea Mosquito Bug (Helopeltis theivora Waterhouse), a Newly Recorded Pest on Arabica coff ee in Northern Thailand

The symptoms of “shot hole leaves” and “excess bud growth” in Arabica coffee have signifi cantly increased in northern Thailand since 2017, resulting in the death of shoots and reduced fl owering, ultimately leading to yield loss. This study investigates whether the “shot hole leaves” symptom is caused by the tea mosquito bug (Helopeltis theivora Waterhouse) (Hemiptera: Heteroptera: Miridae) by rearing tea mosquito bugs with coffee and reproducing the same symptoms under laboratory conditions. Furthermore, we examine whether the “shot hole leaves” symptom is associated with the “excess bud growth” symptom in the fi eld. Our results show that H. theivora can complete their life cycle on Arabica coffee trees. Female bugs lay an average of 87.60±41.82 eggs underneath the soft tissue near young leaves on coffee branches, with a hatching rate of 73.97±6.69%, and an average incubation period of 8.20±0.97 days. The longevity of the fi rst to fi fth nymphal stages was 4.02±1.58, 3.36±0.93, 3.27±0.74, 3.23±0.96, and 3.83±1.18 days, respectively. The adult bugs had a lifespan ranging from 2 to 24 days, with an average of 11.61±7.89 days. The “shot hole leaves” symptom appear approximately 14 days after H. theivora begin feeding on young coffee shoots. We found that the bud number is signifi cantly higher on twigs with the symptom, indicating that both symptoms are caused by H. theivora. The study concludes by discussing control practices of H. theivora on coffee trees.

The Jinggangmycin-induced Mthl2 gene regulates the development and stress resistance in Nilaparvata lugens Stål (Hemiptera: Delphacidae)

Methuselah (Mth) belongs to the GPCR family B, which regulates various biological processes and stress responses. The previous transcriptome data showed jinggangmycin (JGM)-induced Mthl2 expression. However, its detailed functional role remained unclear in brown planthopper, Nilaparvata lugens Stål. In adult N. lugens, the Mthl2 gene showed dominant expressions, notably in ovaries and fat body tissues. The 3rd instar nymphs treated with JGM increased starvation, oxidative stress, and high temperature (34 °C) tolerance of the adults. On the contrary, under dsMthl2 treatment, completely opposite phenotypes were observed. The lipid synthesis genes (DGAT1and PNPLA3) of both females and males treated with JGM in the nymphal stage were observed with high expressions, while the lipolysis of the Lipase 3 gene was observed with low expressions. The JGM increased triglyceride (TG) content, fat body droplet size, and the number of fat body droplets. The same treatment also increased the Glutathione S-transferase (GST), catalase (CAT), and superoxide dismutase (SOD) activities. An increase in the heat shock protein (HSP70 and HSP90) expression levels was also observed under JGM treatment but not dsMthl2. The current study demonstrated the influential role of the Mthl genes, particularly the Mthl2 gene, in modulating the growth and development and stress-responsiveness in N. lugens. Thus, providing a platform for future applied research programs controlling N. lugens population in rice fields.

Silencing of Glutamine: Fructose-6-Phosphate Aminotransferase Impairs Growth and Development in Sogatella furcifera (Hemiptera: Delphacidae).

Glutamine: fructose-6-phosphate aminotransferase (GFAT), the fourth enzyme in the chitin synthesis pathway, exerts wide-ranging effects on the growth and development of organisms. However, the role of GFAT in Sogatella furcifera remains unknown. In this study, the functional significance of the GFAT gene of S. furcifera was analyzed using a reverse transcription-polymerase chain reaction and RNA interference (RNAi) analyses. The complementary DNA sequence of SfGFAT was 3162 bp in length and contained a 2067 bp open reading frame encoding 688 amino acid residues. Structural domain analysis indicated that the SfGFAT protein consisted of one glutamine aminotransferase class 2 domain and two sugar isomerase domains. Expression profile analysis revealed that SfGFAT was expressed throughout the egg, nymph, and adult phases and was strongly expressed on the first day of each nymph stage and in the integuments of five tissues. RNAi results revealed that SfGFAT gene silencing significantly inhibited the mRNA expression of the target gene and resulted in severe mortality among S. furcifera. In summary, these findings demonstrate that SfGFAT plays a critical role in the development of S. furcifera. Moreover, these results may aid in the development of methods to control the spread of S. furcifera.

Identification and functional analysis of serine protease inhibitor gene family of Eocanthecona furcellata (Wolff).

The predatory natural enemy Eocanthecona furcellata plays a crucial role in agricultural ecosystems due to its effective pest control measures and defensive venom. Predator venom contains serine protease inhibitors (SPIs), which are the primary regulators of serine protease activity and play key roles in digestion, development, innate immunity, and other physiological regulatory processes. However, the regulation mechanism of SPIs in the salivary glands of predatory natural enemies is still unknown. In this study, we sequenced the transcriptome of E. furcellata salivary gland and identified 38 SPIs genes named EfSPI1∼EfSPI38. Through gene structure, multiple sequence alignment and phylogenetic tree analysis, real-time quantitative PCR (RT-PCR) expression profiles of different developmental stages and different tissues were analyzed. RNAi technology was used to explore the gene function of EFSPI20. The results showed that these 38 EfSPIs genes contained 8 SPI domains, which were serpin, TIL, Kunitz, Kazal, Antistasin, Pacifastin, WAP and A2M. The expression profile results showed that the expression of different types of EfSPIs genes was different at different developmental stages and different tissues. Most of the EfSPIs genes were highly expressed in the egg stage. The EfSPI20, EfSPI21, EfSPI22, and EfSPI24 genes of the Pacifastin subfamily and the EfSPI35 gene of the A2M subfamily were highly expressed in the nymphal and adult stages, which was consistent with the RT-qPCR verification results. These five genes are positively correlated with each other and have a synergistic effect on E. furcellata, and they were highly expressed in salivary glands. After interfering with the expression of the EfSPI20 gene, the survival rate and predatory amount of male and female adults were significantly decreased. Taken together, we speculated some EfSPIs may inhibit trypsin, chymotrypsin, and elastase, and some EfSPIs may be involved in autoimmune responses. EfSPI20 was essential for the predation and digestion of E. furcellata, and the functions of other EfSPIs were discussed. Our findings provide valuable insights into the diversity of EfSPIs in E. furcellata and the potential functions of regulating their predation, digestion and innate immunity, which may be of great significance for developing new pest control strategies.

Efficiency of cold aqueous and alcoholic extract of Nerium oleander L. flowers. In the control of the sunn insect Hemiptera: Scutelleridae) Eurygaster maura ( Geoffroy) on the wheat crop in Babylon Governorate

The study aimed to know the effect of cold aqueous and alcoholic extract of oleander flowers. Nerium oleander L. on adults and nymphs of Sunnite. The results of the study showed the superiority of the alcoholic extract compared to the aqueous extract, where the alcoholic extract gave the highest death rate of 83.3% at a concentration of 30 mg/ml during 5 days compared to the aqueous extract, which gave a death rate of 80.0% at a concentration of 30 mg/ml during the same period for adults. The results also showed the effect of both alcoholic and aqueous extract on the second nymphal stage, as it gave the highest mortality rate of 100.0 at a concentration of 30 mg/ml during 1 day. As for the effect of the extracts on the fourth nymphal phase, both alcoholic and aqueous extracts gave the highest mortality rate of 100.0% during the 7 days for both extracts. Keywords: sunn insect, wheat, oleander