Dryocosmus kuriphilus (Hymenoptera: Cynipidae) is a gall wasp that induces insect galls on chestnut trees and results in massive yield losses worldwide. Fungi can cause the necrosis of chestnut trees and the death of gall wasps. The aim of this research was to investigate the potential role of D. kuriphilus in the transmission of fungi. We sequenced the ribosomal RNA internal transcribed spacer region 1 of fungi in D. kuriphilus adults, associated insect galls and the galled twigs of Castanea mollissima, using high-throughput sequencing. We compared the species richness, α-diversity and community structure of fungi in D. kuriphilus adults, insect galls and the galled twigs. We provide the first evidence that D. kuriphilus adults shared most fungal species with associated insect galls and the galled twigs, and were dominated by Botryosphaeria sp., Aspergillus sp. and Diaporthe sp. We suggest D. kuriphilus adults may be potential vectors of plant pathogens and may facilitate the transmission of fungi between chestnut trees. Furthermore, the fungi may horizontally transmit among D. kuriphilus adults, associated insect galls and the galled twigs.

A trade-off between the capacity for flight and reproduction has been documented extensively in wing polymorphic female insects, thereby supporting the possible fitness gain due to flightlessness. However, most of these studies were conducted without considering the effect of flight behavior. In the present study, we assessed the flight duration by long-winged (LW) females in the cricket species Velarifictorus aspersus on different days after adult emergence and examined the effect of flight on ovarian development in LW females with different flight capacities. Our results showed that the flight capacity increased with age and peaked after 5 days. In addition, the flight capacity varied among individuals, where most LW females could only take short flights (sustained flight time < 10 min) and only a few individuals could take long flights (sustained flight time > 20 min). In LW female crickets demonstrating only short flights, repeated flying for 30 or 60 min significantly promoted reproductive development. However, in those capable of long flights, reproductive development was affected only after a flight of 60 min. The flight muscles degraded after the start of rapid reproduction in those with both short and long flights. Our results indicated that the critical flight time for switching from flight to reproduction varies among LW V. aspersus female crickets with polymorphic flight behavior.

Dryocosmus kuriphilus (Hymenoptera: Cynipidae) induces galls on chestnut trees, which results in massive yield losses worldwide. Torymus sinensis (Hymenoptera: Torymidae) is a host-specific parasitoid that phenologically synchronizes with D. kuriphilus. Bacteria play important roles in the life cycle of galling insects. The aim of this research is to investigate the bacterial communities and predominant bacteria of D. kuriphilus, T. sinensis, D. kuriphilus galls and the galled twigs of Castanea mollissima. We sequenced the V5–V7 region of the bacterial 16S ribosomal RNA in D. kuriphilus, T. sinensis, D. kuriphilus galls and galled twigs using high-throughput sequencing for the first time. We provide the first evidence that D. kuriphilus shares most bacterial species with T. sinensis, D. kuriphilus galls and galled twigs. The predominant bacteria of D. kuriphilus are Serratia sp. and Pseudomonas sp. Furthermore, the bacterial community structures of D. kuriphilus and T. sinensis clearly differ from those of the other groups. Many species of the Serratia and Pseudomonas genera are plant pathogenic bacteria, and we suggest that D. kuriphilus may be a potential vector of plant pathogens. Furthermore, a total of 111 bacteria are common to D. kuriphilus adults, T. sinensis, D. kuriphilus galls and galled twigs, and we suggest that the bacteria may transmit horizontally among D. kuriphilus, T. sinensis, D. kuriphilus galls and galled twigs on the basis of their ecological associations.

Insect galls are the abnormal growth of plant tissues induced by a wide variety of galling insects and characterized by high concentrations of auxins and cytokinins. It remains unclear whether the auxins and cytokinins affect the bacterial community structure of insect galls. We determined the concentrations of indoleacetic acid (IAA) as an example of auxin, trans-zeatin riboside (tZR) and isopentenyladenine (iP) as cytokinins in Lithosaphonecrus arcoverticus (Hymenoptera: Cynipidae) galls and the galled twigs of Lithocarpus glaber (Fagaceae) using liquid chromatography–tandem mass spectrometry. Moreover, for the first time, we compared the bacterial community structure of L. arcoverticus galls and galled twigs by high-throughput sequencing, and calculated the Spearman correlation and associated degree of significance between the IAA, tZR and iP concentrations and the bacterial community structure. Our results indicated the concentrations of IAA, tZR and iP were higher in L. arcoverticus galls than in galled twigs, and positively correlated with the bacterial community structure of L. arcoverticus galls. We suggest the high concentrations of IAA, tZR and iP may affect the bacterial community structure of L. arcoverticus galls.

Dryocosmus kuriphilus, the chestnut gall wasp, is a globally invasive pest that reproduces by thelytokous parthenogenesis. Despite the absence of conventional sexual recombination, the species has spread widely and persists under diverse environmental conditions, but the genomic features associated with this capacity remain poorly understood. Here, a chromosome-level assembly of D. kuriphilus was compared with seven representative insect genomes, with emphasis on repetitive sequences, orthogroups, and gene-duplication patterns. The 2.28-Gb D. kuriphilus genome contained 79.7% repetitive sequences, including 62.3% transposable elements (TEs), most of which occurred in intergenic regions. OrthoFinder assigned 13,271 D. kuriphilus genes to multi-copy orthogroups, representing 61.5% of the protein-coding gene set. Independent MCScanX analysis classified genes into mutually exclusive dispersed, proximal, tandem, and segmental duplication modes, with segmental and dispersed representing the two largest duplicated-gene classes. D. kuriphilus contained substantially more segmental duplicates than the other species examined. Synonymous-substitution distributions revealed low- and high-Ks components representing different levels of synonymous divergence among duplicated genes, and genes in these components showed distinct functional profiles. Numerous local duplications were found near TEs and included genes involved in host recognition, nutrient utilisation, xenobiotic metabolism, and energy production. Compared with the closely related gall wasp Belonocnema kinseyi, D. kuriphilus has a broader reported distribution and host range and contains higher copy numbers in several gene families associated with chemosensation, detoxification, metabolism, and stress responses. Together, these findings show that the expanded D. kuriphilus genome is characterized by extensive repeat accumulation and increased gene copy number, whereas duplication at multiple scales increased and reshaped the functional gene repertoire. These genomic features identify candidate mechanisms that may contribute to genomic and ecological plasticity, although their adaptive significance requires expression, evolutionary, and functional validation.

The yellow-spined bamboo locust ( Ceracris kiangsu ) is one of the most destructive forest pests in China, causing severe damage to bamboo forests across multiple provinces. Understanding the relationship between its gut microbiota and environmental factors is crucial for revealing its ecological adaptability and migration potential. This study used 16S rRNA high-throughput sequencing to analyze gut bacterial communities of C. kiangsu from six geographically distinct populations in China. The results showed that Firmicutes and Proteobacteria were the dominant phyla, while bacterial diversity and composition varied significantly among populations. Precipitation and sunshine duration were identified as the main environmental factors most strongly associated with microbial community structure. These findings suggest that environmental conditions are strongly associated with variation in the gut microbiota of C. kiangsu , potentially affecting its adaptability and outbreak dynamics. This research provides new insights into the ecological mechanisms underlying pest distribution and offers a microbiome-based foundation for developing sustainable control strategies to reduce the agricultural and forestry losses caused by this species.