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Simple Summary: This study delves into the intricate defense mechanisms of cotton plants against the primary pest Adelphocoris suturalis Jakovlev, which has become a major concern in Bt-cotton fields. Through advanced analytical techniques, this study identified specific changes in the cotton plant's metabolism and protein expression triggered by A. suturalis feeding. These findings revealed a notable increase in the expression of certain α-linolenic acid metabolism pathway-related proteases and a simultaneous decrease in fructose and mannose biosynthesis-related proteases. These molecular responses shed light on the complex interplay between cotton plants and A. suturalis. Therefore, this study not only deepens our understanding of plant–insect interactions but also provides valuable insights for developing innovative strategies to control this cotton pest, thereby offering potential solutions for sustainable cotton cultivation. The recent dominance of Adelphocoris suturalis Jakovlev as the primary cotton field pest in Bt-cotton-cultivated areas has generated significant interest in cotton pest control research. This study addresses the limited understanding of cotton defense mechanisms triggered by A. suturalis feeding. Utilizing LC-QTOF-MS, we analyzed cotton metabolomic changes induced by A. suturalis, and identified 496 differential positive ions (374 upregulated, 122 downregulated) across 11 categories, such as terpenoids, alkaloids, phenylpropanoids, flavonoids, isoflavones, etc. Subsequent iTRAQ-LC-MS/MS analysis of the cotton proteome revealed 1569 differential proteins enriched in 35 metabolic pathways. Integrated metabolome and proteome analysis highlighted significant upregulation of 17 (89%) proteases in the α-linolenic acid (ALA) metabolism pathway, concomitant with a significant increase in 14 (88%) associated metabolites. Conversely, 19 (73%) proteases in the fructose and mannose biosynthesis pathway were downregulated, with 7 (27%) upregulated proteases corresponding to the downregulation of 8 pathway-associated metabolites. Expression analysis of key regulators in the ALA pathway, including allene oxidase synthase (AOS), phospholipase A (PLA), allene oxidative cyclase (AOC), and 12-oxophytodienoate reductase3 (OPR3), demonstrated significant responses to A. suturalis feeding. Finally, this study pioneers the exploration of molecular mechanisms in the plant–insect relationship, thereby offering insights into potential novel control strategies against this cotton pest. [ABSTRACT FROM AUTHOR]

The recent dominance of Adelphocoris suturalis Jakovlev as the primary cotton field pest in Bt-cotton-cultivated areas has generated significant interest in cotton pest control research. This study addresses the limited understanding of cotton defense mechanisms triggered by A. suturalis feeding. Utilizing LC-QTOF-MS, we analyzed cotton metabolomic changes induced by A. suturalis, and identified 496 differential positive ions (374 upregulated, 122 downregulated) across 11 categories, such as terpenoids, alkaloids, phenylpropanoids, flavonoids, isoflavones, etc. Subsequent iTRAQ-LC-MS/MS analysis of the cotton proteome revealed 1569 differential proteins enriched in 35 metabolic pathways. Integrated metabolome and proteome analysis highlighted significant upregulation of 17 (89%) proteases in the α-linolenic acid (ALA) metabolism pathway, concomitant with a significant increase in 14 (88%) associated metabolites. Conversely, 19 (73%) proteases in the fructose and mannose biosynthesis pathway were downregulated, with 7 (27%) upregulated proteases corresponding to the downregulation of 8 pathway-associated metabolites. Expression analysis of key regulators in the ALA pathway, including allene oxidase synthase (AOS), phospholipase A (PLA), allene oxidative cyclase (AOC), and 12-oxophytodienoate reductase3 (OPR3), demonstrated significant responses to A. suturalis feeding. Finally, this study pioneers the exploration of molecular mechanisms in the plant–insect relationship, thereby offering insights into potential novel control strategies against this cotton pest.

Simple Summary: Adelphocoris suturalis is a destructive pest that targets > 270 plants, including cotton, maize, soybean and fruit trees, which has caused tremendous crop losses worldwide. Considering the pesticide resistance and safety issues that are caused by chemicals and the readiness of RNAi technology for use in pest control, the identification of a candidate gene for RNAi remains an active area of research that deserves more attention. Reproduction is the basis for the survival of a species and a targeted disruption to this process would efficiently regulate its population; however, this has not yet been extensively investigated in A. suturalis. In this study, we first isolated a putative A. suturalisaspartic protease (AsAP) gene. The role of AsAP in the reproduction of the pest was subsequently illuminated using the dsRNA-mediated knockdown method. The findings expanded our understanding of A. suturalis reproductive development and provided a potential candidate target gene for the development of RNAi-based pest control strategies. Adelphocoris suturalis Jakovlev (Hemiptera: Miridae) is an omnivorous agricultural pest that has severe economic impacts on a diverse range of agricultural crops. Although the targeted disruption of reproductive development among insects has been proposed as a novel control strategy for pest species, the current understanding of the physiology and molecular mechanisms of A. suturalis reproduction is very limited. In this study, we isolated a putative A. suturalisaspartic protease (AsAP) gene that is highly expressed in the fat body and ovaries of sexually mature females. The double-stranded RNA (dsRNA)-mediated knockdown of AsAP suppressed ovarian development and negatively impacted female fertility, which suggested that it plays an essential role in A. suturalis reproduction. The results of this study could help to expand our understanding of A. suturalis reproductive development and have the potential to facilitate the development of effective strategies for the better control of this pest species. [ABSTRACT FROM AUTHOR]

Adelphocoris suturalis Jakovlev (Hemiptera: Miridae) is an omnivorous agricultural pest that has severe economic impacts on a diverse range of agricultural crops. Although the targeted disruption of reproductive development among insects has been proposed as a novel control strategy for pest species, the current understanding of the physiology and molecular mechanisms of A. suturalis reproduction is very limited. In this study, we isolated a putative A. suturalisaspartic protease (AsAP) gene that is highly expressed in the fat body and ovaries of sexually mature females. The double-stranded RNA (dsRNA)-mediated knockdown of AsAP suppressed ovarian development and negatively impacted female fertility, which suggested that it plays an essential role in A. suturalis reproduction. The results of this study could help to expand our understanding of A. suturalis reproductive development and have the potential to facilitate the development of effective strategies for the better control of this pest species.

The wide-spread culture of transgenic Bt cotton resisting the infamous cotton bollworms has reduced the adoption of broad-spectrum insecticides to a large extent. Consequently, the non-targeted insect Adelphocoris suturalis Jakovlev has become a major cotton pest in China. Entomopathogenic microbes show promising results for controlling this pest in the future, but A. suturalis innate immune responses to these pathogens are poorly understood. Here, we used the entomopathogenic fungus Beauveria bassiana and the Gram-negative pathogenic bacteria Enterobactor cloacae to infect A. suturalis nymphs, followed by high throughput RNA-seq to analyze the immune transcriptomes of A. suturalis in response to the two pathogens. A total of 150 immunity-related genes were identified, including pattern recognition receptors, extracellular signal modulators, signal pathways (Toll, IMD, JNK, and JAK/STAT), and response effectors. Further quantitative real-time PCR analysis demonstrated that B. bassiana and E. cloacae were recognized by different receptors (GNBP and PGRP, respectively); activated Toll pathway and IMD pathway respectively; and both induced expression of the effector gene Defensin. However, melanization is suppressed in B. bassiana-infected nymphs. Collectively, this study provides a transcriptomic snapshot of the A. suturalis immune system, and at the genetic level, gains multifaceted insights of the immune response to fungal and Gram-negative bacterial pathogens. Ultimately this work pioneers the study of molecular mechanisms underlying immune interactions between A. suturalis and its pathogens and assists in the development of novel mitigation strategies to control this pest.

The wide-spread culture of transgenic Bt cotton resisting the infamous cotton bollworms has reduced the adoption of broad-spectrum insecticides to a large extent. Consequently, the non-targeted insect Adelphocoris suturalis Jakovlev has become a major cotton pest in China. Entomopathogenic microbes show promising results for controlling this pest in the future, but A. suturalis innate immune responses to these pathogens are poorly understood. Here, we used the entomopathogenic fungus Beauveria bassiana and the Gram-negative pathogenic bacteria Enterobactor cloacae to infect A. suturalis nymphs, followed by high throughput RNA-seq to analyze the immune transcriptomes of A. suturalis in response to the two pathogens. A total of 150 immunity-related genes were identified, including pattern recognition receptors, extracellular signal modulators, signal pathways (Toll, IMD, JNK, and JAK/STAT), and response effectors. Further quantitative real-time PCR analysis demonstrated that B. bassiana and E. cloacae were recognized by different receptors (GNBP and PGRP, respectively); activated Toll pathway and IMD pathway respectively; and both induced expression of the effector gene Defensin. However, melanization is suppressed in B. bassiana -infected nymphs. Collectively, this study provides a transcriptomic snapshot of the A. suturalis immune system, and at the genetic level, gains multifaceted insights of the immune response to fungal and Gram-negative bacterial pathogens. Ultimately this work pioneers the study of molecular mechanisms underlying immune interactions between A. suturalis and its pathogens and assists in the development of novel mitigation strategies to control this pest. [ABSTRACT FROM AUTHOR]

Adelphocoris suturalis Jakovlev (Hemiptera: Miridae) is an insect pest that causes severe agricultural damage to cotton and many other important crops. In insects, olfaction is very important throughout their lifetime. There are two groups of small soluble proteins, named odorant binding proteins (OBPs) and chemosensory proteins (CSPs), which are suggested to participate in the initial biochemical recognition steps of insect olfactory signal transduction. In this study, a total of 16 OBPs (12 classical OBPs and 4 plus-C OBPs) and 8 CSPs, were identified in the antennal transcriptome of A . suturalis . The sex- and tissue-specific profiles of these binding protein genes showed that 13 of the 16 OBP transcripts were highly expressed in the antennae of both sexes, and 4 OBPs ( AsutOBP1 , 4 , 5 and 9 ) were expressed higher in the male antennae compared to the female antennae. Three CSPs ( AsutCSP1 , 4 and 5 ) were expressed specifically in the antennae of both sexes, and AsutCSP1 was expressed higher in the male antennae than in the female antennae. Our findings identify several novel OBP and CSP genes for further investigation of the olfactory system of A . suturalis at the molecular level. [ABSTRACT FROM AUTHOR]

Background Adelphocoris suturalis Jakovlev is a major cotton pest in Southern China. Metathoracic scent glands (MTGs) produced pheromones that play an important role in survival and population propagation of this species, and also show great potential for pest control. Up to the present, there is little information that underlined the molecular basis of the pheromone biosynthesis of this bug. It is essential to clarify genes involved in the production of pheromone components, and also in the regulation of the variation of the blend ratio. Results We sequenced the transcriptome of metathoracic scent glands (MTGs) of A. suturalis . A total of 52 million 91-bp-long reads were obtained and assembled into 70,296 unigenes with a mean length of 691 bp. Of these unigenes, a total of 26,744 (38%) unigenes showed significant similarity to known proteins in the NCBI database (E-value < 10 − 5 ). Out of 26,744 hits, 9258 sequences were classified functionally into 25 COG categories, 16,473 unigenes were assigned to 242 KEGG pathways. Through blast searches of public database, a series of transcripts encoding proteins potentially related to the pheromone biosynthesis were selected, and the gene expression patterns were verified by qRT-PCR. The qRT-PCR results indicated that Asdelta9-DES , AsFAR , AsAOX , Ascarboxylesterase , AsNT-ES and AsATFs have a higher expression level in the period when female A. suturalis release sex pheromones. Conclusions These data constitutes the first transcriptomic analysis exploring the repertoire of genes expressed in insect MTGs. We identified a large number of potential pheromone biosynthetic pathway genes. In this context, our study provides an invaluable resource for future exploration of molecular mechanisms of pheromone biosynthesis in A. suturalis , as well as other hemipteran species. [ABSTRACT FROM AUTHOR]