Knowledge regarding the regulatory effects of biofertilizers on yield and soil microbial communities during stand development in perennial woody crops remains limited. We investigated the responses of soil physicochemical properties, microbial biomass, and community functional gene profiles, and hazelnut (Corylus heterophylla × C. avellana) yield to biofertilizer application (Bacillus subtilis and B. licheniformis) across different stand ages. Compared with control (chemical fertilizer), biofertilizer increased hazelnut yield by 17.7% (4-year-old stand), P and K concentrations in leaves (19.4% and 20.1%) and roots (36.7% and 16.9%) across all stands. Biofertilizer altered soil microbial community composition, including the gram-positive to gram-negative (GP/GN) bacterial ratio and the relative abundances of dominant bacterial (Actinobacteriota) and fungal (Ascomycota) phyla. Functional genes associated with nitrogen (N) cycling, and organic phosphorus (P) mineralization were significantly enriched in the 4-year-old and 5-year-old stands under biofertilizer. Soil properties strongly influenced microbial biomass, community structure and composition. Structural equation modelling showed that biofertilizer indirectly enhanced microbial N- and P-cycling functions via shifts in the GP/GN and F/B (fungi to bacteria) ratio. The negative association between P-starvation response regulation and soil available P content indicates that biofertilizer mitigated P limitation by promoting organic mineral solubilization. Biofertilizer indirectly increased P and K concentrations in hazelnut tree through soil microbial composition structure (GP/GN) by improving soil available P and K. These results demonstrate the potential of biofertilizers to support sustainable hazelnut production by increasing yields in young stands, improving soil quality through enhanced availability of soil P and K, and maintaining productivity while reducing reliance on chemical fertilizers. Our findings suggest that a combination of reduced chemical fertilizer and biofertilizer represents the most effective strategy for sustaining and enhancing long-term productivity in older stands.

The widespread use of insecticides in forest ecosystems has raised significant concerns about their nontarget effects on biological control agents (BCAs), such as predators and parasitoid wasps, which play a pivotal role in natural pest suppression. This review evaluates the lethal and sublethal impacts of various insecticide classes on BCAs. Systemic insecticides, while effective in controlling pests, have been shown to impair the reproduction, foraging behavior, and host-seeking abilities of BCAs, leading to disruptions in pest regulation and biodiversity loss. In Pinus koraiensis (Siebold & Zucc) forests, parasitoid wasps such as Baryscapus dioryctriae (Yang & Song) are critical for managing pests such as Dioryctria pryeri. However, insecticide exposure threatens their efficacy, exacerbating pest outbreaks and ecosystem instability. The deployment of B. dioryctriae as a BCA provides a sustainable alternative to chemical control, with demonstrated success in reducing pest populations and minimizing environmental impacts. Integrated pest management (IPM) frameworks that combine biological control with targeted insecticide use offer promising solutions to mitigate nontarget effects. Future research should focus on optimizing mass-rearing and release strategies for BCAs, exploring semiochemical-based pest disruption and assessing the long-term ecological consequences of low-dose insecticide exposure. By advancing IPM approaches, forest managers can achieve effective pest control while preserving the ecological integrity and biodiversity of forest ecosystems.

The hazelnut weevil larvae (Curculio dieckmanni) is a major pest of nut weevils, spending part of its life cycle in the soil and causing significant damage to hazelnut crops. Moreover, its concealed feeding behavior complicates effective control with chemical insecticides. The entomopathogenic nematode Steinernema carpocapsae, which efficiently kills weevil larvae, offers a promising biological control agent. To investigate the molecular responses of hazelnut weevil larvae to nematode infection, we employed integrated transcriptomic and proteomic analyses following infection by S. carpocapsae. Our results revealed substantial alterations in gene expression, particularly the upregulation of immune-related transcripts such as antimicrobial peptides (AMPs) and stress-responsive proteins like heat shock protein 70 (HSP70). Furthermore, significant metabolic reprogramming occurred, marked by the downregulation of carbohydrate metabolic pathways and activation of energy conservation mechanisms. Although we observed an overall correlation between mRNA and protein expression levels, notable discrepancies highlighted the critical roles of post-transcriptional and post-translational regulatory processes. Collectively, these findings advance our understanding of the molecular interaction between insect hosts and pathogenic nematodes and contribute valuable knowledge for enhancing the effectiveness of EPN-based pest management strategies.

Forest ecosystems play a vital role in global carbon (C) sequestration, which is intricately linked to root nitrogen (N) uptake. However, the strategies that forest vegetation employ to take up different forms of soil N, and the implications for forest management, remain insufficiently understood. To address this issue, we employed duallabelled (13C-15N) tracers for three forms of available N (NH4+, NO3- , and glycine) in field experiments conducted in both natural and afforested stands in northeast China. As the growing season progressed, significant but nonuniform changes were observed in the N content, natural abundance of 15N in plant roots, and soil N properties, including soil NH4+, NO3- , amino acids, microbial biomass N, and the natural abundance of 15N. Whether in natural or artificial forests, the uptake rates and patterns of NH4+, NO3 - and glycine by plant roots also varied, resulting in N niche differentiation among the coexisting plant species in terms of N form and timing. Principal component analysis and percentage similarity in N uptake patterns further revealed distinct N niche differentiation. Our results suggest that the uptake of different forms of soil N is likely driven by opportunistic rather than strictly preferential responses. This could provide an important basis for the N niche differentiation among coexisting plant species in the forest communities. Recognizing the temporal differentiation of N uptake niches during afforestation is essential to foster inter-specific coexistence, particularly in N-limited habitats. These findings provide critical insights for optimizing species composition in afforestation practices, thereby alleviating inter-specific competition, facilitating species coexistence, and maintaining productive forest ecosystems.

Fine root biomass, morphology, and soil microbial biomass were examined in a Pinus koraiensis orchard under four fertilization levels (0, 0.75, 1.25, 2.0 kg compound fertilizer per tree representing control, low-, moderateand high-level) across three seasons. Fertilization increased soil available nitrogen, phosphorus, and potassium contents, enhanced soil cation exchange capacity, and reduced soil pH from 5.56 to 4.80. Accompanied by the significant shifts in fine root traits and soil microbial community. Fertilization increased specific root length (SRL: 57-77 %) and specific root area (SRA: 30-39 %) across growing season. High-level fertilization reduced soil total microbial (17-27 %) and bacterial PLFAs (21-22 %) in July and September. High- and moderate-level fertilization decreased soil fungal PLFAs (20-26 %) in July. Moderate-level fertilization increased the fungi to bacteria ratio (F:B) by 34 % (May), 16 % (July), and 17 % (September). Fine root biomass negatively correlated with F:B, soil total microbial, bacterial, and fungal biomass. F:B was negatively related to fine root diameter, positively associated with SRL and SRA. Taking the response of fine root traits, soil microbial assembly, soil properties to fertilization together, moderate-level fertilization (1.25 kg per tree) may represent a threshold rate, optimizing nutrient availability while maintaining microbial balance. Seasonal variations further revealed that fine roots shifted from acquisitive strategies in spring and summer to conservative strategies in autumn, impacting soil microbial community composition. Our findings highlight the interconnected responses of fine roots and soil microorganisms to fertilization and seasonal dynamics, providing insights for sustainable forest management.

BACKGROUND: Cuticular proteins (CPs) play essential roles in forming cuticular structures in insects. However, the specific functions and regulatory mechanisms of CPs remain largely unexplored. In this study, the Larval cuticular protein 17 (HcLCP-17) gene was identified from Hyphantria cunea, a highly destructive and polyphagous forest pest. To investigate the role of HcLCP-17 in cuticular function and transcriptional regulation mediated by 20E-responsive transcription factors (ERTFs), we employed RNA interference (RNAi) and yeast one-hybrid assay techniques. Additionally, we examined the molecular mechanism by which chlorbenzuron, a type of benzoylphenylurea (BPU) that functions as a chitin synthesis inhibitor (CSI), affects the 20E signaling pathway and ultimately regulates HcLCP-17 expression. RESULTS: HcLCP-17 encodes a polypeptide consisting of 393 amino acids, which includes a chitin-binding domain. Silencing HcLCP-17 resulted in a disturbance in the structural organization of the larval cuticle and a notable reduction in chitin levels. HcLCP-17 expression was controlled by the interaction between Broad-Complex (Br-C) and beta Fushi Tarazu Factor-1 (beta FTZ-F1) with its promoter fragment. Furthermore, the inhibitory effect of chlorbenzuron on HcLCP-17 expression was found to be potentially mediated by Br-C and beta FTZ-F1. CONCLUSION: The study presents a novel mode of action for the 20E signaling pathway in regulating the expression of CPs and reveals the potential mode-of-action of BPUs in insect cuticles. These findings provide a theoretical basis for future utilization of LCP-17 as a pesticide target making a significant contribution to the development of effective pest management strategies. (c) 2024 Society of Chemical Industry.

In this paper, four species of Omphale Haliday, O. longigena Li & Li, sp. nov., O. longitarsus Li & Li, sp. nov., O. rectisulcus Li & Li, sp. nov., and O. xanthosoma Li & Li, sp. nov., are described as new to science; four species, O. brevibuccata Szelényi, O. connectens Graham, O. melina Yefremova & Kriskovich, and O. obscura (Förster) are reported from China for the first time; and the male of O. melina is reported for the first time in the world. A key to all known species of the genus Omphale in China is provided.

Insects’ growth and development are highly dependent on energy supply, with sugar metabolism playing a pivotal role in maintaining homeostasis and regulating physiological processes. The present study investigated the effects of exendin-4, a glucagon-like peptide-1 receptor (GLP-1R) agonist, on the growth, development, glycolysis, and energy metabolism of fourth-instar larvae of the fall webworm, Hyphantria cunea. We determined the impact of exendin-4 on larval growth and nutritional indices, analyzed the responses of glycolytic and metabolic pathways, and revealed the underlying regulatory mechanisms. Exendin-4 treatment significantly decreased growth and nutritional indices, influenced the activity of digestive enzymes, and induced changes in metabolite profiles, particularly affecting energy substance metabolism. We observed an increase in the glycogen content and a decrease in glucose and trehalose levels in the hemolymph, suggesting a regulatory effect on blood sugar homeostasis. Furthermore, exendin-4 promoted glycolysis by enhancing the activities and expressions of key glycolytic enzymes, leading to an increase in pyruvate production. This was accompanied by a reduction in ATP levels and the activation of AMP-activated protein kinase (AMPK), which may underlie the growth arrest in larvae. Our findings provide novel insights into the effects of exendin-4 on insect responses from an energy metabolism perspective and may contribute to the development of GLP-1R agonists for pest management.

BACKGROUND:Healthy cultures of arthropods are important for pest management programs (e.g. biocontrol). Little is known about how rearing conditions may affect pheromonal interactions. We investigated how rearing histories and densities affect pheromone emission/production in two stink bug species (Hemiptera: Heteroptera), the predatory bug Arma custos, a biocontrol agent, and the bean bug Riptortus pedestris, a pest on legume crops. RESULTS:Nymphs from newly established laboratory colonies of both species produced higher amounts of the defense (dispersal) compound, 4-oxo-(E)-hexenal (OHE), in the presence of conspecific nymphs. Also, when two or more A. custos males were placed together, the dorsal abdominal glands (DAGs) ceased to release aggregation pheromone, whereas the metathoracic glands (MTGs) increased the emission of defensive odors. These changes resulted from exposure to conspecific pheromone odors, as confirmed by exposing bugs to pheromone standards. Hence, pheromone emissions in these stink bugs are readily changed in response to the odors of conspecifics, which may become a problem after long-term rearing. Indeed, an old laboratory colony of A. custos (~30 generations) exhibited less-developed DAGs and reduced pheromone production. Instead, males released significantly more defensive odors from the enlarged MTGs. Furthermore, long-term rearing conditions appeared to favor nymphs that were able to share space with conspecifics by releasing less OHE, which has not yet occurred in the new laboratory colonies. CONCLUSION:Rearing density affects pheromone release in newly established laboratory colonies of stink bug species, whereas long-term rearing results in new pheromonal compositions coinciding with adaptive changes in gland development. © 2023 Society of Chemical Industry.

Hazel (Corylus avellana) is easily attacked by Curculio nucum L. To better understand the physiological mechanisms underlying the different resistance of cultivars to C. nucum, we determined the insect-resistant compounds, plant hormones contents, and enzyme activities in the nutshells of three hazel cultivars (DW, B21, and MZ) before (preexisting defense) and after (induced defense) C. nucum chewing. The findings demonstrated that the resistance of three hazel cultivars to C. nucum differed significantly (p < 0.05): the damage rate of MZ with 17.57% was highest, followed by DW (11.23%), and then B21 (7.15%). The contents of insect-resistant compounds (total terpenoid, tannin, total phenol, flavonoids, cellulose, and lignin) varied with hazel cultivars, both before and after C. nucum chewing, except for cellulose and lignin before induction. The level of plant hormones and defense enzyme activities of hazelnut enhanced due to C. nucum induction. Pearson correlation results revealed that the hazelnut damage rate was significantly negatively correlated with jasmonic acid (JA) (R2 = 0.812), SOD (R2 = 0.671), salicylic acid (SA) (R2 = 0.878), and terpenoids (R2 = 0.774), and significantly positively correlated with flavonoids (R2 = 0.696), celluloses (R2 = 0.501), POD (R2 = 0.758), and abscisic acid (ABA) (R2 = 0.978). The hazelnut defense to C. nucum was negatively related to cellulose contents, and not to lignin contents, but was significantly positively related to the ratio of cellulose-to-lignin (R2 = 0.703). Our results suggested that the hazel against C. nucum attack responded by improving plant hormones contents and enzyme activities in the nutshells. A particular cellulose-to-lignin ratio provides the most effective physical structural defense properties in the nutshells.

Benzoylurea chitin synthesis inhibitors（BPUs） are widely used to prevent and control pests in agriculture and forestry. The types, synthetic routes and applications on forestry pest of benzoylurea were reviewed, and systematically analyzed the differences in mechanism of chemical compound against target pest. The effects of benzoylurea compounds on ion channels of insect cuticle, chitin synthase and sulfonylurea receptor proteins in insects were discussed respectively. Research trend and direction of the kind of insecticide had prospected based on the current progress in forestry pest control.

Fructose 1, 6-diphosphate (FDP) is an endogenous intermediate in the glycolytic pathway, as well as an allosteric activator of phosphofructokinase (PFK). Based on the role in promoting glycolysis, FDP has been widely used as a therapeutic agent for mitigating the damage of endotoxemia and ischemia/reperfusion in clinical practice. However, the effect of exogenous FDP-induced glycolysis activation on insect carbohydrate metabolism and chitin synthesis remains largely unclear. Here, we investigated for the first time the effects of FDP-Na, an allosteric activator of PFK, on the growth and development of Hyphantria cunea larvae, a serious defoliator in agriculture and forestry, especially on glycolysis and chitin synthesis. The results showed that FDP-Na significantly restrained the growth and development of H. cunea larvae and resulted in larval lethality. After treatment with FDP-Na, hexokinase (HK), phosphofructokinase (PFK) and pyruvate kinase (PK) were significantly activated, and HcHK2, HcPFK, HcPK were dramatically upregulated, which suggested that FDP-Na enhanced glycolysis in H. cunea larvae. Meanwhile, FDP-Na also distinctly impacted chitin biosynthesis by disturbing transcriptions of genes in the chitin synthesis pathway, resulting in changes of chitin contents in the midgut and epidermis of H. cunea larvae. Therefore, we considered that FDP-Na caused the growth and development arrest, and impacted chitin biosynthesis, probably by disturbing in vivo glycolysis and carbohydrate metabolism in H. cunea larvae. The findings provide a new perspective on the mechanism by which glycolysis regulates insect growth and development, and lay the foundation for exploring the potential application of glycolysis activators in pest control as well.

Chlorbenzuron is a kind of benzoylphenylureas (BPUs), which plays a broad role in insect growth regulators (IGRs), with an inhibitory effect on chitin biosynthesis. However, BPUs how to regulate glycolysis and insect growth remains largely unclear. Here, we investigated the effects of chlorbenzuron on growth, nutritional indices, glycolysis, and carbohydrate homeostasis in Hyphantria cunea, a destructive and highly polyphagous forest pest, to elucidate the action mechanism of chlorbenzuron from the perspective of energy metabolism. The results showed that chlorbenzuron dramatically restrained the growth and nutritional indices of H. cunea larvae and resulted in lethality. Meanwhile, we confirmed that chlorbenzuron significantly decreased carbohydrate levels, adenosine triphosphate (ATP), and pyruvic acid (PA) in H. cunea larvae. Further studies indicated that chlorbenzuron caused a significant enhancement in the enzyme activities and mRNA expressions of hexokinase (HK), phosphofructokinase (PFK), and pyruvate kinase (PK), resulting in increased glycolytic flux. Expressions of genes involved in the AMP-activated protein kinase (AMPK) signaling pathway were also upregulated. Moreover, chlorbenzuron had remarkable impacts on H. cunea larvae from the perspective of metabolite enrichment, including the tricarboxylic acid (TCA) cycle and glycolysis, indicating an energy metabolism disorder in larvae. The findings provide a novel insight into the molecular mechanism by which chlorbenzuron abnormally promotes glycolysis and eventually interferes with insect growth and nutritional indices.

The steroid hormone 20‐hydroxyecdysone (20E) has been described to regulate fat body lipid metabolism in insects, but its accurate regulatory mechanism, especially the crosstalk between 20E‐induced lipid metabolism and gluconeogenesis remains largely unclear. Here, we specially investigated the effect of 20E on lipid metabolism and gluconeogenesis in the fat body of Hyphantria cunea larvae, a notorious pest in forestry. Lipidomics analysis showed that a total of 1 907 lipid species were identified in the fat body of H. cunea larvae assigned to 6 groups and 48 lipid classes. The differentially abundant lipids analysis showed a significant difference between 20E‐treated and control samples, indicating that 20E caused a remarkable alteration of lipidomics profiles in the fat body of H. cunea larvae. Further studies demonstrated that 20E accelerated fatty acid β‐oxidation, inhibited lipid synthesis, and promoted lipolysis. Meanwhile, the activities of pyruvate carboxylase, phosphoenolpyruvate carboxykinase, fructose‐1,6‐bisphosphatase, and glucose‐6‐phosphatase were dramatically suppressed by 20E in the fat body of H. cunea larvae. As well, the transcriptions of genes encoding these 4 rate‐limiting gluconeogenic enzymes were significantly downregulated in the fat body of H. cunea larvae after treatment with 20E. Taken together, our results revealed that 20E disturbed fat body lipid homeostasis, accelerated fatty acid β‐oxidation and promoted lipolysis, but negatively regulated gluconeogenesis in H. cunea larvae. The findings might provide a new insight into hormonal regulation of glucose and lipid metabolism in insect fat body.

E74 is a key transcription factor induced by 20E, which plays a broad role in many physiological events during insect growth and development, including vitellogenesis, organ remodeling and new tissue formation, programmed cell death and metamorphosis. However, whether it is involved in regulating insect chitin biosynthesis remains largely unclear. Here, the E74 gene was identified for the first time from Hyphantria cunea, a notorious defoliator of forestry. Thereafter, the role of HcE74 in regulating growth, development and chitin synthesis in H. cunea larvae was evaluated. Bioinformatics analysis showed that HcE74 shared the highest identity (95.53%) with E74A of Spodoptera litura, which belonged to Ets superfamily. The results of RNAi bioassay showed that the larval mortality on 6 d after HcE74 knockdown was up to 51.11 ± 6.94%. Meanwhile, a distinct developmental deformity phenotype was found when HcE74 was silenced. These results indicated that HcE74 plays an important role in the development and molting of H. cunea larvae. Moreover, HcE74 knockdown also significantly decreased the expression of four key genes related to chitin synthesis, including glucose-6-phosphate isomerase (HcG6PI), UDP-N-acetylglucosamine pyrophosphorylase (HcUAP), chitin synthetase A (HcCHSA), and chitin synthetase B (HcCHSB). As a result, the content of chitin in midgut and epidermis decreased by 0.54- and 0.08-fold, respectively. Taken together, these results demonstrated that HcE74 not only plays a critical role in the growth and molting of H. cunea larvae, but also probably participates in the transcriptional regulation of genes involved in chitin biosynthesis.

[目的]比较伊氏杀线虫真菌Esteya vermicola(EV菌)在碳、氮营养源培养下的代谢差异,并找到重要代谢物或信号分子.[方法]选取培养真菌的碳培养基[主要为马铃薯葡萄糖肉汤培养基(PDB)]和培养细菌的氮培养基(主要为酵母粉),将EV菌在2种培养基上25℃条件下培养7 d,收获菌丝体并提取代谢产物.采用非靶标的高效液相色谱-质谱联用技术(HPLC-MS),在阴、阳离子模式下对代谢物组分进行分析和鉴定,并分析差异显著代谢物的代谢通路.[结果]共得到498种代谢物,阴、阳离子模式分别有176和362种,其中2种模式共同含有40种.差异显著的代谢物共有444种,占总数的89.2％,其中阴、阳离子模式分别有162和310种,有28种为2种模式共有.主成分和偏最小二乘判别分析均可使碳、氮培养条件下的代谢物聚为不同的簇并显著分离.氮培养条件下,磷酸胍基乙酸酯和对甲酚硫酸盐是大量产生且特有的代谢物;重要代谢物尿囊素、光色素、吲哚和海藻糖产量显著上调.通路分析将显著上调和下调的代谢物分别富集到氨基酸和糖类代谢相关的代谢通路.[结论]EV菌在碳培养和氮培养条件下呈现明显的代谢差异,代谢通路主要涉及糖类和氨基酸代谢.重要代谢物可为EV菌的高效培养和应用提供基础.

Metformin, considered to be a potent AMPK activator, is widely used for clinical therapy of cancer and diabetes due to its distinct function in regulating cell energy balance and body metabolism. However, the effect of metformin-induced AMPK activation on the growth and development of insects remains largely unknown. In the present study, we focused on the role of metformin in regulating the growth and development of Hyphantria cunea, a notorious defoliator in the forestry. Firstly, we obtained the complete coding sequences of HcAMPKα2, HcAMPKβ1, HcAMPKγ2 from H. cunea, which encoded a protein of 512, 281, and 680 amino acids respectively. Furthermore, the phylogenetic analysis revealed that these three subunits were highly homologous with the AMPK subunits from other lepidopteran species. According to the bioassay, we found metformin remarkably restrained the growth and development of H. cunea larvae, and caused molting delayed and body weight reduced. In addition, expressions of HcAMPKα2, HcAMPKβ1, and HcAMPKγ2 were upregulated 3.30-, 5.93- and 5.92-folds at 24 h after treatment, confirming that metformin activated AMPK signaling at the transcriptional level in H. cunea larvae. Conversely, the expressions of two vital Halloween genes (HcCYP306A1 and HcCYP314A1) in the 20E synthesis pathway were remarkably suppressed by metformin. Thus, we presumed that metformin delayed larval molting probably by impeding 20E synthesis in the H. cunea larvae. Finally, we found that metformin accelerated glycogen breakdown, elevated in vivo trehalose level, promoted chitin synthesis, and upregulated transcriptions of the genes in chitin synthesis pathway. Taken together, the findings provide a new insight into the molecular mechanisms by which AMPK regulates carbohydrate metabolism and chitin synthesis in insects.

低温冷藏是延长天敌昆虫货架期的有效方法之一.昆虫的存活率、生殖力、田间寄生(捕食)力等是评估天敌昆虫耐冷藏力的重要指标.昆虫耐冷藏力受冷藏前、冷藏中和冷藏后的各种外源(非生物)因子和内源(生物)因子的影响.这些因子主要包括温度、湿度、光周期、氧浓度、冷藏持续时间、冷藏前的预处理、冷藏过程中的温度处理(混合低温)等外源因子和虫体能量物质的储备、繁殖方式、年龄/龄期、滞育(休眠)状态、营养等内源因子.本文对影响天敌昆虫耐冷藏性的内源因子和外源因子的种类以及产生这些影响的生理学机制等进行了综述,以期为天敌昆虫低温储藏技术研究和生产方案的制定提供依据.

Adaptation of fine root plasticity to soil nutrients heterogeneity in natural forest ecosystems has not been well explored. The study aimed to determine seasonal variations of fine root traits in Pinus koraiensis natural forests and explore the relationship between fine root traits and soil properties. Root and soil samples were collected from the coniferous broad-leaved mixed forest (BP), monospecific P. koraiensis forest (MP), and coniferous mixed forest (CP). Soil available phosphorus (P) content for MP was 31.7% and 39.8% lower than for BP and CP. Soil cation exchange capacity (CEC) for MP was lower by 23.5% and 27.2% than for BP and CP, respectively. In July, specific root lengths and root surface areas for BP and CP (mixed forests) were significantly higher than for MP (monospecific forest). A structural equation model showed that CEC had a significant effect on fine root traits. Root diameter, root volume density, and root surface area density were negatively correlated with CEC. Fine root traits plasticity of P. koraiensis are closely related to soil available nutrient contents, CEC, and species composition at the ecosystem level.

As a typical glycolytic inhibitor, 3-bromopyruvate (3-BrPA) has been extensively studied in cancer therapy in recent decades. However, few studies focused on 3-BrPA in regulating the growth and development of insects, and the relationship and regulatory mechanism between glycolysis and chitin biosynthesis remain largely unknown. The Hyphantria cunea, named fall webworm, is a notorious defoliator, which caused a huge economic loss to agriculture and forestry. Here, we investigated the effects of 3-BrPA on the growth and development, glycolysis, carbohydrate homeostasis, as well as chitin synthesis in H. cunea larvae. To elucidate the action mechanism of 3-BrPA on H. cunea will provide a new insight for the control of this pest. The results showed that 3-BrPA dramatically restrained the growth and development of H. cunea larvae and resulted in larval lethality. Meanwhile, we confirmed that 3-BrPA caused a significant decrease in carbohydrate, adenosine triphosphate (ATP), pyruvic acid (PA), and triglyceride (TG) levels by inhibiting glycolysis in H. cunea larvae. Further studies indicated that 3-BrPA significantly affected the activities of hexokinase (HK), phosphofructokinase (PFK), pyruvate kinase (PK), glucose 6-phosphate dehydrogenase (G6PDH) and trehalase, as well as expressions of the genes related to glycolysis, resulting in carbohydrate homeostasis disorder. Moreover, it was found that 3-BrPA enhanced 20-hydroxyecdysone (20E) signaling by upregulating HcCYP306A1 and HcCYP314A1, two critical genes in 20E synthesis pathway, and accelerated chitin synthesis by upregulating transcriptional levels of genes in the chitin synthesis pathway in H. cunea larvae. Taken together, our findings provide a novel insight into the mechanism of glycolytic inhibitor in regulating the growth and development of insects, and lay a foundation for the potential application of glycolytic inhibitors in pest control as well.