Pachyrhinus yasumatsui Kono et Morimoto is a major pest of Chinese jujube, which is widespread in northern China and causes severe economic losses in the jujube industry. Chemosensory genes play crucial roles in insect behaviors. Currently, little is known about chemosensory genes in P. yasumatsui. In the present study, antennal transcriptomes of female and male adult P. yasumatsui were annotated. In total, 113 genes involved in chemosensory functions were identified, including 41 odorant receptors, 28 odorant-binding proteins, 16 ionotropic receptors, 15 chemosensory proteins, 9 gustatory receptors, and 4 sensory neuron membrane proteins. Subsequently, the phylogenetic analyses of these olfactory-related proteins in P. yasumatsui were conducted using multiple sequence alignment. Furthermore, sex-specific expression levels of 113 genes were analyzed based on fragments per kilobase of transcript per million mapped reads (FPKM). Then, the quantitative real-time PCR (RT-qPCR) was used to quantify gene expression profiles of 28 P. yasumatsui OBPs (PyasOBPs) and 15 CSPs (PyasCSPs). The results revealed that 20 PyasOBPs and 13 PyasCSPs exhibited significantly higher expression in the antennae than in the bodies, suggesting that they might have functions in olfaction. Moreover, some OBPs and CSPs (PyasOBP6, PyasOBP7, PyasOBP16, PyasOBP21, and PyasCSP4) exhibited female-biased expression, indicating that they might take part in several female-specific behaviors. This study will promote the understanding of olfactory mechanism in P. yasumatsui, and our findings lay the groundwork for developing environmentally friendly pest management measures.

Spodoptera frugiperda, known as the fall armyworm (FAW), a major invasive pest in corn, is rapidly spreading all over the world. Similarly to other Lepidoptera insects, FAW pupae usually develop in soil. Therefore, the soil moisture level is expected to be an important factor impacting their growth. In order to study the development and emergence of FAW pupae in a 100% soil moisture environment, three factors were selected for experiments in this study: the duration of saturated (100%) moisture treatment (0 h, 24 h, 48 h, and 72 h), the initial soil moisture before the larvae entered the soil (0 and 50%), and pupal age (1 day, 4 days, and 7 days). We discovered that (1) the emergence percentage of FAW pupae decreased with an increase in the saturated soil moisture treatment time, and the emergence percentage dropped to 0 after 72 h of continuous treatment; (2) the younger the age of FAW pupae, the more susceptible they were to being affected by saturated soil moisture treatment, and the emergence percentage of 7-day-old pupae was higher than that of 1-day-old pupae; and (3) FAW larvae that pupated in dry soil (0% moisture) had pupae with higher survival rates under subsequent 100% soil moisture stress, whereas those pupating in moderately moist soil (50% moisture) had lower survival rates under the same condition. Our study showed that the initial moisture level of the soil and the length of time the soil is saturated have a significant impact on FAW pupal development. The three factors of excessive stress time, wet initial soil moisture (50%), and lower pupal age ultimately lead to a decrease in the emergence percentage and survival rate of FAW pupae.

Sympiezomias velatus (Chevrolat) (Coleoptera: Curculionidae) has caused serious damage on jujube trees (Ziziphus jujuba Mill) in northern China. Semiochemicals emerging from the host are essential in the process of insects identifying and localizing the host. The highly expressed odorant-binding protein 1 of S. velatus (SvelOBP1) was assumed to play a possible role in the recognition of host volatiles. In this study, SvelOBP1 was cloned based on the antennal transcriptome of S. velatus. The recombinant SvelOBP1 protein was expressed in Escherichia coli and purified by Ni-NTA resin. The predicted protein SvelOBP1 belonged to a classic OBP subfamily. The expression patterns revealed that SvelOBP1 was mainly expressed in the antennae of both males and females, whereas the expression of SvelOBP1 in other body parts could be neglected. The fluorescence binding assay indicated that SvelOBP1 displayed very strong binding affinities to dibutyl benzene-1,2-dicarboxylate and (Z)-hex-3-en-1-ol (K_i = 6.66 ± 0.03 and 7.98 ± 0.06 μM). The molecular docking results showed that residues Trp114, Phe115 and Asp110 may be involved in binding to both dibutyl benzene-1,2-dicarboxylate and (Z)-hex-3-en-1-ol and may have a great impact on odorant recognition of S. velatus. Our results provide evidence that SvelOBP1 might participate in the olfactory molecular perception of S. velatus and would promote the development of pest attractants for S. velatus control.

Sucra jujuba Chu, 1979 (Lepidoptera: Geometridae) is a major insect pest in jujube plantation. In this study, we have sequenced the complete mitochondrial genome of S. jujuba. The circular genome was 15,557 bp in length and contained 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), two ribosomal RNA genes (rRNAs), and one AT-rich region (GenBank accession no. MZ507574). The nucleotide composition was significantly biased (A, T, C, and G were 41.85%, 39.65%, 10.97%, and 7.53%, respectively) with A + T contents of 81.50%. The Bayesian phylogenetic analysis of the concatenated nucleotide sequences of 13 PCGs from 30 species in the subfamily Ennominae and two outgroup species was performed. The results indicated that S. jujuba was closely related to Amraica recursaria in the subfamily Ennominae.

In this study, the complete mitochondrial genome of Ancylis sativa was sequenced and assembled. The circular genome is 15,262 bp in length and comprises 37 genes: 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, and two ribosomal RNA (rRNA) genes, along with one AT-rich region. The average nucleotide composition is A = 40.95%, T = 38.04%, C = 13.01%, and G = 8.00%, resulting in an A + T content of 78.99%. Phylogenetic analysis indicated that Ancylis sativa was closely related to Ancylis unculana in the subfamily Olethreutinae, which can enhance the evolutionary and phylogeographic study of Ancylis sativa.

Stephanitis macaona Drake, 1948 (Hemiptera: Tingidae) is an important pest of camphor trees. The complete mitochondrial genome of S. macaona was sequenced and assembled in this paper. The circular genome is 15,407 bp in length and contains 37 genes (13 protein-coding genes, 22 transfer RNA genes, 2 ribosomal RNA genes) as well as one AT-rich region (GenBank accession no. PP868166). The average nucleotide composition is 44.04% for A, 34.40% for T, 12.50% for C, and 9.06% for G. The percentage of A + T contents is 78.44%. The maximum-likelihood phylogenetic analysis of the concatenated nucleotide sequences of 13 PCGs from 21 species in the family Tingidae and two outgroup species was performed. The results indicated that Stephanitis macaona does not form sister relationships with any other species, instead nesting within the genus Stephantis. This study provides significant molecular data for advancing the evolutionary and phylogeographic analysis of S. macaona.