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The antennal sensilla play an important role in many behavioral activities of insects. The fungivorous beetle Triplax ainonia Lewis (Erotylidae) is an important pest which prefers to feed on Pleurotus mushrooms. In order to clarify the types, number, and distribution of the antennal sensilla of male and female T. ainonia, scanning electron microscopy was used. The results showed that there were five sensillum types on the antennae of adults male and female, including Böhm's bristles (BB), sensilla chaetica (three subtypes: SC 1, SC 2, and SC 3), sensilla basiconica (three subtypes: SB 1, SB 2, and SB 3), sensilla trichodea (ST), and sensilla styloconica (SS). Among all the sensilla, the number of SB 2 was the most abundant in both sexes. We found that there was no sexually dimorphic in the sensillum types, but there were differences in the number, lengths, and diameters of some sensilla between males and females. Based on the information of the morphology and distribution of the sensilla, the potential functions of the antennal sensilla of T. ainonia adults were discussed. The results of this study provide a basis for further study on the behavioral ecology and electrophysiology of the fungivore beetles of the Erotylidae. [ABSTRACT FROM AUTHOR]

Ensuring the safety of insecticides to natural enemy insects of pests is crucial for integrating chemical and biological control strategies. Broflanilide, a novel meta-diamide insecticide, exhibits high insecticidal activity against Myzus persicae (Sulzer) (Hemiptera: Aphididae). To integrate chemical and biological control against M. persicae , we assessed the toxicity of broflanilide to Aphidius gifuensis , and evaluated its safety and sublethal effects. The LC10, LC25, and LC50 values of broflanilide against A. gifuensis were 0.733 mg/L, 1.613 mg/L, and 3.852 mg/L, respectively. The selectivity toxicity ratio of broflanilide to A. gifuensis was 1.516, indicating higher toxicity to M. persicae compared to A. gifuensis. The risk quotient of broflanilide to A. gifuensis adults was 6.18. The percent reduction in the emergence of the parasitoid pupae was −1.15, with a risk grade of 1. The sublethal concentration of broflanilide had no significant influence on the intrinsic rate of increase (r), finite rate of increase (λ), net reproductive rate (R 0), and mean fecundity (F) of A. gifuensis in the F1 generation. The mean generation time (T) increased by 0.51 days and 0.39 days in the LC10 and LC25 treatments, respectively; the difference between LC10 treatment and the control was significant, while the difference between LC25 treatment and the control was not significant. The results showed that the sublethal concentration of broflanilide did not have a significant inhibitory effect on the population growth of A. gifuensis. [ABSTRACT FROM AUTHOR]

Oribatid mites play a crucial role in nutrient cycling, litter decomposition, and humus formation in the ecosystem. Here, an Illumina HiSeq platform was used to sequence the complete mitochondrial (mt) genome of Ceratozetella imperatoria. The mt genome is a circular molecule of 14,229 bp (GenBank number: PP419053), and a total of 37 genes were described. The start codon in all 13 protein-coding genes (PCGs) included ATT, ATA, TTG, and ATG, the stop codon of all 13 protein-coding genes was TAA, TAG, and single T. The AT skew and GC skew were 0.153 and 0.263 observed across the whole mt genome of Ceratozetella imperatoria. Besides the negative AT skew in PCGs, rRNA and CR, positive AT skew and GC skew were detected in the remaining components. A phylogenetic tree of 29 mite species was constructed using PCGs by the maximum likelihood method. Ceratozetoidea and Oripodoidea were closely related and become sister group relationships among them. [ABSTRACT FROM AUTHOR]

Bruchidius coreanus is a serious pest on Gleditsia sinensis Lam during seed storage, causing significant losses to their yield in southwest China. To gain insight into their behavioral mechanisms, the external morphology, ultrastructure, and distribution of sensilla on antennae, maxillary palps, and labial palps of both male and female B. coreanus were observed using a scanning electron microscope. The results revealed that both male and female adults had serrated antennae comprising a scape, a pedicel, and nine flagellomeres (F1–F9). There were eight types and seven subtypes of antenna sensilla observed in both sexes, including Böhm sensilla (BS), two subtypes of sensilla chaetica (SC1 and SC2), two subtypes of sensilla trichodea (ST1 and ST2), three subtypes of sensilla basiconica (SB1, SB2, and SB3), sensilla auricillica (SA), sensilla styloconicum (SS), capitate pegs (CP), and sensilla cavity (SCa). The average length of BS and ST (ST1 and ST2) showed significant differences between males and females. Furthermore, the number of SC (SC1 and SC2), ST1, and SCa differed significantly between the sexes. Four types of sensilla were found on the maxillary palps and labial palps, with the length of ST on these palps significantly differing between males and females. Additionally, SS on male labial palps was significantly longer than in females. The number of SC significantly differed between the male and female maxillary palps and labial palps, while ST and SS showed significant differences in the maxillary palps. These findings will contribute to further electrophysiological recording and behavioral research. Research Highlights: The external morphology and distribution of various sensilla on the antennae, maxillary palps, and labial palps of Bruchidius coreanus were described.Eight types and seven subtypes of antenna sensilla were observed on the antennae, while four types of sensilla were observed on the maxillary palps and labial palps.The capitate pegs were found exclusively on the antennae of female B. coreanus. [ABSTRACT FROM AUTHOR]

Efficient rearing is necessary for the successful biological control of pests. The braconid wasp, Microplitis manilae, is a natural solitary parasitoid of larval Spodoptera frugiperda. However, the effect of the host diet on the parasitism success of M. manilae on S. frugiperda larvae remains unclear. Here, we determined the parasitism rate, oviposition, eclosion rate, developmental period and offspring sex ratio of M. manilae parasitizing S. frugiperda fed with fresh corn leaves or an artificial diet. M. manilae parasitizing the corn leaf‐fed S. frugiperda larvae exhibited a significantly higher parasitism rate (40%), oviposition (62.50 eggs/female) and eclosion rate (81.38%) than the wasp parasitizing the artificial diet‐fed S. frugiperda larvae (22%, 38.33 eggs/female, and 58.73%, respectively). Furthermore, M. manilae parasitizing the corn leaf‐fed S. frugiperda larvae exhibited a significantly shorter developmental period (16.35 days) and lower sex ratio (1.17) than the wasp parasitizing the artificial diet‐fed S. frugiperda larvae (18.00 and 2.15 days, respectively). Overall, M. manilae exhibited better parasitic success on corn leaf‐fed S. frugiperda larvae than on artificial diet‐fed S. frugiperda larvae. Therefore, using fresh corn leaf‐fed S. frugiperda is the most suitable strategy for mass‐rearing M. manilae for pest biocontrol. Our findings suggest M. manilae as an effective biocontrol candidate for controlling S. frugiperda in corn fields. [ABSTRACT FROM AUTHOR]

The predatory gall midge, Aphidoletes aphidimyza (Rondani), and tobacco aphid cocoon wasp, Aphidius gifuensis Ashmead, are important natural enemies of Myzus persicae (Sulzer) (Hemiptera: Aphididae). Predation by A. aphidimyza and A. gifuensis can regulate M. persicae; however, how interspecific interference competition affects their foraging efficiency is unknown. Here, we investigated the consumption and parasitization abilities of A. aphidimyza 3rd instar larva and A. gifuensis adults under various conditions. Consumption of parasitized aphids by A. aphidimyza 3rd instar larvae was significantly lower than that of nonparasitized controls, with a substantial increase in handling time. The presence of A. gifuensis adults did not significantly affect the predation capacity of A. aphidimyza larvae. Relative to controls, A. aphidimyza larvae predation trace (PT) and imago activity significantly decreased A. gifuensis parasitism rates at different aphid densities. Further, A. aphidimyza larvae PT increased the A. gifuensis handling time of M. persicae, whereas the presence of A. aphidimyza adults had the opposite effect. Coexistence with heterospecific natural enemies reduced the parasitic capacity of A. gifuensis, whereas A. aphidimyza larvae predation capability was influenced to a lesser extent. Our results demonstrate that intraguild interactions strongly influence the predatory and parasitic efficacy of A. aphidimyza and A. gifuensis, although the effect on A. gifuensis was more pronounced. For effective biological control of M. persicae using A. aphidimyza and A. gifuensis, we recommend releasing A. aphidimyza first to mitigate intraguild predation and enhance the overall success of the pest control program., (© The Author(s) 2024. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

In July 2023, a new leaf spot disease emerged on tobacco leaves in Meitan County, Guizhou Province, China (27°20'18" - 28°12'30"N, 107°15'36" - 107°41'08"E, average altitude 972 meters). Initially, the symptoms showed raised yellow-brown spots; subsequently, the lesions expanded and became broken and perforated, leading to a significant loss of economic value, the prevalence rate exceeded 30%. For isolation, two tissue fragments (0.2 × 0.2 cm) of symptomatic leaves were sterilized in 75% ethanol for 30 s, 3% NaClO for 2 min, and were washed 3 times in sterilized distilled water, and were subsequently inoculated on potato dextrose agar (PDA), and incubated at 28°C for 9 days in the dark. The two strains CW16 and CW28 were isolated using the single hyphae method (Nouri et al. 2023). Both strains formed pale to yellow white colonies on PDA. Conidia had three constricted transverse septa and 1 to 2 longitudinal septa in the central cells, with thick and hyaline conidiophores and mostly globose, pale brown conidia with slightly constricted septa, their average size were measured as 13.4-22.4×8.358-13.347 μm (n = 50). Genomic DNA was extracted from the isolated strains CW16 and CW28. The internal transcribed spacer regions 1 and 2 as well as 5.8S nuclear ribosomal RNA (ITS), large subunit nrRNA (LSU), and partial DNA-directed RNA polymerase II second largest subunit (RPB2) genes were amplified using primers (Cui et al. 2023). The sequences had been deposited in GenBank under accession numbers ITS: PP024201, PP024205; LSU: PP024207, PP024209; RPB2: PP060480, PP060481. The sequences analysis revealed a high similarity of 99.74 to 100% between strains CW16 and CW28 with P. palmicola isolate KM42 (ITS OQ875842, LSU OQ875844, RPB2 OQ883943) in GenBank. Using BLAST for homology matching, two isolates (CW16, CW28) and with the sequences of the ten type isolates from GenBank, phylogenetic analysis was conducted using the Maximum Likelihood method in MEGA (11.0) software based on ITS, LSU and RPB2 sequences, which showed that strains CW16, CW28 clustered in the same score as the Pseudopithomyces palmicola, confirming the morphological and molecular characteristics identification. The pathogenicity tests were conducted on healthy tobacco plants with 4-5 leaves (Fig. S1B), the isolated strains, CW16 and CW28, were used to inoculate the healthy tobacco leaves, while blank PDA was used as a control. All plants were maintained in a greenhouse at 28°C with a relative humidity of 90%. After 9 days, necrotic spots were observed on all tobacco leaves inoculated with CW16 and CW28 fungal plugs, while the blank PDA-inoculated tobacco leaves showed no symptoms. Based on morphological and molecular characteristics, the same pathogen P. palmicola was identified from the inoculated leaves, fulfilling Koch's postulates. This study represents the first reported of tobacco leaf spot caused by P. palmicola in China and provides a theoretical basis for future prevention and control measures.