First report of Pseudopithomyces palmicola causing leaf spot on tobacco in China.

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.

First Report of Leaf Spot on Zanthoxylum bungeanum Caused by Nigrospora sphaerica in China.

Zanthoxylum bungeanum Maxim., a deciduous shrub in Zanthoxylum genus of the Rutaceae family, has not only highly economical values as condiment and medicine, but also significantly ecological values in soil and water conservation. In March 2023, a typical leaf spot disease on Z. bungeanum (Variety "Xiao Qingjiao") was observed in the field with an area of 26.68 ha with 35% incidence and 25.4% disease intensity in Zhenfeng County (25°38'57.60″ N, 105°64'98.64″ E, 1,156 m), Guizhou Province, China. The symptom leaves showed as irregularly shaped necrotic lesions, brown to dark brown with black margin. 30 samples with typical symptoms were collected and cut into 0.5 cm × 0.5 cm pieces. Their surfaces were disinfected with 1.5% NaClO for 2 min followed by 75% ethanol for 35 s, rinsed three times with sterile distilled water, finally incubated on PDA plates at 27°C. A total of 36 isolates were obtained through single-spore cultivation. The colonies on PDA were fluffy with abundant aerial mycelia and covered the whole plates (diameter 90 mm) in 7 days. Conidia were brown to black, single-celled, smooth, spherical or oblate, 12.0-17.0 × 12.5-18.5 µm (av. = 14.5 × 15.5 µm, n = 50) and grew on a colorless transparent vesicle at the apical cell of conidiophores. The morphological characteristics were similar with N. sphaerica (Wang et al. 2017). The 5.8S DNA (ITS), translation elongation factor 1-alpha (TEF1-α) and ß-tubulin (TUB2) genes were amplified with primers ITS4/ITS5, EF1-728F/EF2, and BT2A/BT2B, respectively (White et al. 1990; Carbone and Kohn 1999, O'Donnell et al. 1998; Glass and Donaldson 1995). The ITS, TEF1-α and TUB2 sequences of two randomly selected isolates, GUCC 21-187 and GUCC 21-235, had > 99% nucleotide identities (ITS: 99.60% (504/506 bp, OR646539) and 99.61% (506/508 bp, OR640300); TEF: 100% (470/470 bp, OR654285) and 100.00% (471/471 bp, OR654286); TUB: 100.00% (408/408 bp, OR661269) and 99.52% (411/413 bp, OR661270), respectively) with those sequences of N. sphaerica (LC 7294) in GenBank (KX985932, KY019397 and KY019602, respectively). The phylogenetic tree based on sequences of ITS, TEF1-α and TUB2 indicated that GUCC 21-187 and GUCC 21-235 were most closely related to N. sphaerica (LC 7294), supported with 100%/100%/1 bootstraps. Based on morphological characteristics and molecular datasets analyses, the isolates were identified as N. sphaerica. 10 healthy 2-years-old Z. bungeanum plants were sprayed with conidial suspensions (1 × 106 conidia/mL) of the isolates and the other 5ere sprayed with sterile water as the controls, all the treated plants were cultivated in a glasshouse at 25°C under 85% relative humidity. Typical leaf spot symptoms appeared on inoculated Z. bungeanum plants after 8 days, while the control plants remained asymptomatic. N. sphaerica was re-isolated from the lesions of inoculated plants and identified by morphological and molecular identification. Pathogenicity test was performed three times with analogous results, fulfilling Koch's postulates. N. sphaerica had been reported as a common pathogen on a variety of plants including sugarcane, kiwifruit and blueberry (Cui et al. 2018; Chen et al. 2016; Wright et al. 2008). To our knowledge, this is the first report of leaf spot disease caused by N. sphaerica on Z. bungeanum in China. Our report would be helpful to Z. bungeanum growers to recognize this leaf spot disease, and corresponding measures could be taken to minimize or avoid the economic losses caused by it.

Leptosphaerulina americana causing holing disease on tobacco in China.

Tobacco (Nicotiana tabacum) is one of the most important industrial crops in the world. Its leaves are the main raw material for cigarettes, but they are often threatened by fungal pathogens in the production process (Wang et al. 2022). From May to June 2022, a disease of tobacco (cv K326) (15% of plants) in a 0.3-ha field in Jingxi of Guangxi Province showed symptoms of local necrosis and perforation of middle and basal leaves (Fig S1). Pieces of leaf tissue (3 × 3 mm) were excised from the edge of the necrotic lesion of each plant, treated with 75% ethanol for 10 s, soaked in 2% NaClO solution for 1-2 min, rinsed with sterile water for three times, and then plated on potato dextrose agar（PDA）medium and incubated at 28°C. Isolate TJYA13 was used for subsequent studies. After 8 days, the colony margin was yellowish brown and irregular, the center was black and plicated. The isolate TJYA13 was incubated on oatmeal agar medium at 28°C for 4 days, and many pseudothecia were observed embedded on the surface of the medium. Pseudothecium was globose or subglobose, dark brown, and size was 184.7-304.7 µm × 187.5-340.5 µm (n=20). Ascospores were usually wrapped by the saccate ascus in pseudothecium, cylindrical or ellipsoidal, with 5-6 transverse septa, and size was 12.2-18.5 µm × 35.6-51.8 µm (n=80). The morphological characteristics of ascospores were consistent with a Leptosphaerulina species (Hou et al. 2020). For accurate identification, the genomic DNA of isolate TJYA13 was extracted with Ezup Column Fungi Genomic DNA Purification Kit (Sangon, Shanghai, China). The ITS region, 28s ribosomal RNA (LSU), ß-tubulin (TUB), and RNA polymerase II second largest subunit (RPB2) were amplified with primers ITS1/ITS4 (Gardes and Bruns 1993; White et al. 1990), LROR/LR7 (Rehner and Samuels 1994), Btub2Fd/Btub4Rd (Woudenberg et al. 2009), and RPB2-5F2/fRPB2-7cR (Liu et al. 1999), respectively and sequenced at Sangon Biotech (Sichuan, China). The sequences were deposited in GenBank (accession nos. OP926927, OP926933, OP939419, OP939422). The phylogenetic analysis grouped the isolate TJYA13 within the L. americana clade (Fig S2) (Hou et al. 2020). Pathogenicity of the isolate TJYA13 was verified on four healthy tobacco plants (cv K326). The mycelial plugs were inoculated on leaves sterilized with 75% ethanol, and control plants were inoculated with sterile PDA plugs. Plants were incubated at 28 ℃ and 78% humidity. After 10 days, the leaves inoculated with mycelial plugs had symptoms similar to those in the field, but there were no symptoms on the control leaves. L. americana were reisolated from the leaves inoculated with the mycelial plugs. To the best of our knowledge, this is the first report of L. americana causing holing disease on tobacco in China. This disease may reduce yields and lower quality of flue-cured tobacco leaf. Therefore, the emergence of tobacco holing disease should be noted to prevent potential damage to tobacco production in Guangxi. Reference 1. Hou L. W., et al. 2020. Stud. Mycol. 96: 309-396 2. Liu, Y. J., et al. 1999. Mol. Biol. Evol. 16:1799. 3. Rehner, S. A., and Samuels, G. J. 1994. Mycol. Res. 98:625. 4. Wang H. et al. 2022. Microorganisms. 10: 1890. 5. White, T. J., et al. 1990. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA. 6. Woudenberg, J. H. C., et al. 2009. Persoonia 22:56. The author(s) declare no conflict of interest. Funding: Funding was provided by Guangxi Zhuang Autonomous Region Tobacco Monopoly Bureau (grant no. 202,145,000,024,006). Tobacco (Nicotiana tabacum) is one of the most important industrial crops in the world. Its leaves are the main raw material for cigarettes, but they are often threatened by fungal pathogens in the production process (Wang et al. 2022). From May to June 2022, a disease of tobacco (cv K326) (15% of plants) in a 0.3-ha field in Jingxi of Guangxi Province showed symptoms of local necrosis and perforation of middle and basal leaves (Fig S1). Pieces of leaf tissue (3 × 3 mm) were excised from the edge of the necrotic lesion of each plant, treated with 75% ethanol for 10 s, soaked in 2% NaClO solution for 1-2 min, rinsed with sterile water for three times, and then plated on potato dextrose agar（PDA）medium and incubated at 28°C. Isolate TJYA13 was used for subsequent studies. After 8 days, the colony margin was yellowish brown and irregular, the center was black and plicated. The isolate TJYA13 was incubated on oatmeal agar medium at 28°C for 4 days, and many pseudothecia were observed embedded on the surface of the medium. Pseudothecium was globose or subglobose, dark brown, and size was 184.7-304.7 µm × 187.5-340.5 µm (n=20). Ascospores were usually wrapped by the saccate ascus in pseudothecium, cylindrical or ellipsoidal, with 5-6 transverse septa, and size was 12.2-18.5 µm × 35.6-51.8 µm (n=80). The morphological characteristics of ascospores were consistent with a Leptosphaerulina species (Hou et al. 2020). For accurate identification, the genomic DNA of isolate TJYA13 was extracted with Ezup Column Fungi Genomic DNA Purification Kit (Sangon, Shanghai, China). The ITS region, 28s ribosomal RNA (LSU), ß-tubulin (TUB), and RNA polymerase II second largest subunit (RPB2) were amplified with primers ITS1/ITS4 (Gardes and Bruns 1993; White et al. 1990), LROR/LR7 (Rehner and Samuels 1994), Btub2Fd/Btub4Rd (Woudenberg et al. 2009), and RPB2-5F2/fRPB2-7cR (Liu et al. 1999), respectively and sequenced at Sangon Biotech (Sichuan, China). The sequences were deposited in GenBank (accession nos. OP926927, OP926933, OP939419, OP939422). The phylogenetic analysis grouped the isolate TJYA13 within the L. americana clade (Fig S2) (Hou et al. 2020). Pathogenicity of the isolate TJYA13 was verified on four healthy tobacco plants (cv K326). The mycelial plugs were inoculated on leaves sterilized with 75% ethanol, and control plants were inoculated with sterile PDA plugs. Plants were incubated at 28 ℃ and 78% humidity. After 10 days, the leaves inoculated with mycelial plugs had symptoms similar to those in the field, but there were no symptoms on the control leaves. L. americana were reisolated from the leaves inoculated with the mycelial plugs. To the best of our knowledge, this is the first report of L. americana causing holing disease on tobacco in China. This disease may reduce yields and lower quality of flue-cured tobacco leaf. Therefore, the emergence of tobacco holing disease should be noted to prevent potential damage to tobacco production in Guangxi.

Influence of Pyranose and Spacer Arm Structures on Phloem Mobility and Insecticidal Activity of New Tralopyril Derivatives.

Six new conjugates were designed and synthesized by introducing glucose, methyl glucuronate or glucuronic acid moieties on tralopyril. Phytotoxicity and phloem mobility results demonstrated that the introduction of glucose, methyl glucuronate or glucuronic acid moieties can simultaneously solve the tough phytotoxicity problem and phloem mobility transformation of tralopyril. Conjugates 12 and 18 containing the glucuronic acid moiety exhibited higher phloem mobility than conjugates 9, 11, 15 and 17. Conjugates 15, 17 and 18 with methoxymethyl groups on the tralopyril pyrrole nitrogen atom showed activity against Plutella xylostella, while conjugates 9, 11 and 12 with a methene group on the pyrrole N showed no activity. Cabbage roots were incubated in a buffered solution containing conjugates 15, 17 and 18 at 4 mM for 72 h. Only 18 showed systemic insecticidal activity with 100% mortalityagainst P. xylostella, while 15 and 17 showed lower activity andchlorfenapyr showed no activity. The glucuronic acid promoiety imparted more phloem mobility to tralopyril than glucose and methyl glucuronate. The methoxymethyl group bond on the tralopyril skeleton was the key factor in determining the insecticidal activity of the conjugates. A promising systemic proinsecticide containing glucuronic acid and tralopyril moieties was proposed.

Effects of Temperature on Development and Survival of Orthopygia glaucinalis (Lepidoptera: Pyralidae) Reared on Platycarya strobilacea.

The larvae of Orthopygia glaucinalis (L.) (Lepidoptera: Pyralidae) are used to produce insect tea in Guizhou, China. We investigated the development and survival of O. glaucinalis reared on dried leaves of Platycarya strobilacea under laboratory conditions at 19, 22, 25, 28, 31, 34, and 37°C. The duration of development from egg deposition to adult emergence decreased significantly with increasing temperature from 19 to 31°C, whereas the duration of egg and overall development significantly increased at 34°C. Based on the extreme-value distribution function, the optimal temperature for survival of overall development was 24.89°C, and the larval stage was most susceptible to temperature extremes. The common linear model and the Ikemoto and Takai linear model were used to determine the relationship between temperature and the developmental rate, and estimated the low-temperature threshold (11.44 and 11.62°C, respectively) and the threshold constant (1220.70 and 1203.58 degree-days, respectively) of O. glaucinalis. Nonlinear models were used to assess in fitting the experiment data and to estimate the high temperature thresholds (34.00 to 39.08°C) and optimal temperatures (31.61 to 33.45°C). An intrinsic optimal temperature of 24.18°C was estimated for overall development using the Sharpe-Schoolfield-Ikemoto (SSI) model. Model-averaged parameter estimates and the unconditional standard error were also estimated for the temperature thresholds. Based on the biological parameters and model selection, we concluded that common linear, Lactin-1, and SSI models performed better for predicting the temperature-dependent development of O. glaucinalis. Our findings enable breeders to optimize the developmental rate of O. glaucinalis and improve the yield of insect tea.

Two new species and two new records of Ptecticus Loew (Diptera: Stratiomyidae: Sargiinae) from China.

Two species, Ptecticus brevispinus sp. nov. and P. guangxiensis sp. nov., from China are described and illustrated. Additional two species, P. longispinus Rozkosný & Kovac, 2003 and P. melanurus (Walker, 1848), are recorded from China for the first time. A checklist of the known Chinese Ptecticus Loew, 1855 species together with their geographical distribution and a new identification key (19 spp.) are presented.

Safety evaluation and sublethal effect of broflanilide on Aphidius gifuensis.

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 (R0), 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.

Functional morphology of antennae and sensilla of the fungivore beetle, Triplax ainonia Lewis (Coleoptera: Erotylidae).

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.

Morphology and distribution of sensilla on antennae and mouthparts of the adult bruchid beetles, Bruchidius coreanus (Coleoptera: Bruchidae).

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.

Intraguild species presence alters Aphidoletes aphidimyza (Diptera: Cecidomyiidae) and Aphidius gifuensis (Hymenoptera: Braconidae) foraging responses.

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 Oriental genus Nasimyia (Diptera: Stratiomyidae): Geographical distribution, key to species and descriptions of three new species.

In this paper, three new species of Nasimyia Yang & Yang, 2010, N. eurytarsa sp. nov., N. rozkosnyi sp. nov. and N. elongoverpa sp. nov. from the Oriental region are described and illustrated; N. nigripennis Yang & Yang, 2010 is found to be a junior synonym of N. megacephala Yang & Yang, 2010 (syn. nov.). Chelonomima signata de Meijere 1924 is combined as Pseudomeristomerinx signata (de Meijere, 1924) comb. nov.. Keys to the Oriental genera of Pachygasterinae with elongate abdomens and the species of Nasimyia are provided, as well as distribution maps of the four species of Nasimyia.

Three new species of Atkinsoniella (Arthropoda, Insecta, Hemiptera, Cicadellidae, Cicadellinae) from China, with an updated checklist to the known species worldwide.

The sharpshooter genus Atkinsoniella Distant, 1908 includes 99 valid species worldwide. Here, three new species from China are described and illustrated: Atkinsoniellastenopyga, A.wangi, and A.yingjiangensisspp. nov. An updated checklist of the known Atkinsoniella species worldwide based on the data of previous literature and studied materials is also provided. All the type specimens of three new species are deposited at the Institute of Entomology, Guizhou University, Guiyang, China.

A new species of Neohydatothrips (Thysanoptera: Sericothripinae) from China.

Neohydatothrips stachyurus sp. n. is described from Guizhou, China. Morphologically, this new Sericothripinae species is characterized by the shape of blotch on pronotum and the distribution of microtrichia on abdominal segments. The distribution of Neohydatothrips species from China also is discussed.

Complete mitochondrial genome of Gortyna guizhouensis Wu, Yang, and Han, 2022 (Lepidoptera, Noctuidae) from China.

Gortyna guizhouensis Wu, Yang, and Han, 2022 (Lepidoptera, Noctuidae) is a newly discovered moth species that feeds on tobacco piths during the larval stage. In this study, we sequenced and analyzed the complete mitochondrial genome (mitogenome) of G. guizhouensis larvae via next-generation sequencing. The mitogenome was 15,441 bp long with an overall A + T content of 79.1%, 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), two ribosomal RNA subunit genes and one control region. The phylogenetic tree, based on the nucleic acid sequences of 13 shared PCGs of 20 Noctuidae species, revealed that G. guizhouensis is in a well-supported clade with Striacosta albicosta.

The complete mitochondrial genome of Picromerus lewisi Scott 1874 (Hemiptera: Pentatomidae: Asopinae).

Picromerus lewisi Scott (Hemiptera: Pentatomidae) is a widely used natural enemy, through this study, we proved that its complete mitochondrial genome of it had similar characteristics to those of other Hemiptera. The mitogenome of P. lewisi is a circular molecule of 18,123 bp with 74.0% A + T content, containing 13 protein-coding genes (PCGs), 22 tRNAs, 2 rRNAs, and one control region. Phylogenetic tree based on 13 PCGs from 17 Panheteroptera species (two species of the Cimicomorpha are used as outgroup, 15 species belong to the Pentatomomorpha) suggested that P. lewisi has a closer relationship with E. thomsoni within Pentatomidae family.

Transgenerational effects of multiple mating in Spodoptera litura Fabricius (Lepidoptera: Noctuidae).

Polyandrous mating can result in sexual conflict and/or promote the evolution of mating patterns. Does multiple mating by females support the genetic benefits hypothesis and can it be validated as an evolutionary strategy? If we are to decipher the consequences of sexual interactions and understand the interplay of sexual conflict and multiple generational benefits, the transgenerational effects need to be followed over multiple generations. We investigated the effects of three mating patterns, single mating, repeated mating, and multiple mating, on parental Spodoptera litura copulation behavior, and then identified the impact on the development, survival, and fecundity of the F1 and F2 generations. Fecundity was not significantly affected in the F1 generation but was substantially enhanced in the F2 generation. There was a reversal of offspring fitness across the F2 generations from the F1 generations in progeny produced by multiple mating. In addition, the intrinsic rate of increase, finite rate of increase and net reproductive rate in the F1 generation the multiple mating treatment was significantly lower than in the single mating treatment, but there was no apparent effect on the F2 generation. Repeated mating had no significant effects on progeny fitness. We postulate that multiple mating imposes cross-transgenerational effects and may ultimately influence multigenerational fitness in S. litura.

Pest management of postharvest potatoes: lethal, sublethal and transgenerational effects of the ectoparasitic mite Pyemotes zhonghuajia on the potato worm Phthorimaea operculella.

BACKGROUND: Potato, Solanum tuberosum, is one of the most important food crops in the world, playing a significant role in global food security. However, many potato industries and farms may suffer losses of tuber yield and quality in storage due to lepidopteran pests. Here, we evaluated the effectiveness of an ectoparasitic idiobiont mite Pyemotes zhonghuajia in the biological control of the potato tuber moth (PTM) Phthorimaea operculella by determining the lethal, sublethal (nonconsumptive) and transgenerational effects of P. zhonghuajia of various population densities and exposure durations on PTM survival, development and reproduction. RESULTS: Pyemotes zhonghuajia females were capable of killing all instar stages of PTM, while resistance to mite parasitism increased with the development of PTM life stage. The mortality of mature larvae (i.e., fourth instar) and pupae increased with increasing mite density and exposure duration. P. zhonghuajia imposed significant negative sublethal impacts on PTM pupation rate, female fecundity and adult longevity but not on immature development. The sublethal stress was transgenerational, resulting in lower reproduction in the offspring generation. CONCLUSION: P. zhonghuajia induces lethal, sublethal and transgenerational effects and significantly decreases PTM survival and reproductive out, demonstrating its high efficiency in the biological control of PTM. Our study provides insight into the mechanisms underlying the nonconsumptive effects of parasitism in an ectoparasite-host system and delivers critical information for the design and implementation of augmentative releases of P. zhonghuajia in the biological control of PTM in potato storage. © 2023 Society of Chemical Industry.

Effects of cold storage after cold acclimation on the fitness of Habrobracon hebetor (Hymenoptera: Braconidae).

Habrobracon hebetor (Say) (Hymenoptera: Braconidae) is a cosmopolitan, idiobiont, and gregarious ectoparasitoid, which can parasitize the larvae of several pyralid and noctuid moths. However, adult parasitoids require cold storage to ensure that adequate individuals are available when a pest outbreak occurs. To understand the effects of cold storage after acclimation on offspring fitness of H. hebetor, the development, fecundity, population parameters, and paralysis rate of the F1 generation were evaluated using an age-stage, two-sex life table. Four pairing treatments were used in this study, with refrigerated males and females (ReF×ReM), unrefrigerated females and refrigerated males (UnF×ReM), refrigerated females and unrefrigerated males (ReF×UnM), and unrefrigerated females and males (UnF×UnM, control). Cold storage after acclimation had no significant effect on the fecundity or oviposition period of F0-generation H. hebetor. Moreover, the survival rate (Sa = 61.43%), proportion of females (Nf/N = 0.41), intrinsic rate of increase (r = 0.3450), finite rate of increase (λ = 1.4121), net reproduction rate (R0 = 149.47), and net paralysis rate (C0 = 74.52) of ReF×UnM and UnF×UnM (Sa = 50.00%, Nf/N = 0.34, r = 0.3297, λ = 1.3881, R0 = 155.69, C0 = 62.90, respectively) treatments were significantly higher than those of the ReF×ReM treatment (Sa = 45%, Nf/N = 0.16, r = 0.2277, λ = 1.2558, R0 = 68.81, C0 = 31.61, respectively) (except for the Sa of UnF×UnM treatment), and there was no significant difference between the 2 treatments. Overall, it is advisable to avoid simultaneous cold storage of female and male parasitoids or to add unrefrigerated males appropriately when using cold-stored parasitoids to control pests.

Selection and validation of optimal reference genes for RT-qPCR analyses in Aphidoletes aphidimyza Rondani (Diptera: Cecidomyiidae).

Aphidoletes aphidimyza is a predator that is an important biological agent used to control agricultural and forestry aphids. Although many studies have investigated its biological and ecological characteristics, few molecular studies have been reported. The current study was performed to identify suitable reference genes to facilitate future gene expression and function analyses via quantitative reverse transcription PCR. Eight reference genes glyceraldehyde-3-phosphate dehydrogenase (GAPDH), RPS13, RPL8, RPS3, α-Tub, ß-actin, RPL32, and elongation factor 1 alpha (EF1-α) were selected. Their expression levels were determined under four different experimental conditions (developmental stages, adult tissues, sugar treatment, and starvation treatment) using qRT-PCR technology. The stability was evaluated with five methods (Ct value, geNorm, NormFinder, BestKeeper, and RefFinder). The results showed that GAPDH, RPL32, and EF1-α were ranked as the best reference gene combinations for measuring gene expression levels among different developing stages and in various starvation treatments. RPL8 and RPS3 were recommended to normalize the gene expression levels among different adult tissues. RPL32, ß-actin, and EF1-α were recommended sugar-feeding conditions. To validate the utility of the selected reference pair, RPL8, and RPS3, we estimated the tissue-biased expression level of a chemosensory protein gene (AaphCSP1). As expected, AaphCSP1 is highly expressed in the antennae and lowly expressed in the abdomen. These findings will lay the foundation for future research on the molecular physiology and biochemistry of A. aphidimyza.

A new species of the genus Gortyna Ochsenheimer, 1816 from China, with notes on the larval feeding habits (Lepidoptera, Noctuidae, Noctuinae: Apameini).

A new species of the genus Gortyna Ochsenheimer, 1816, G. guizhouensis sp. n., is described from Guizhou Province, China. Adults and genitalic structures of the new species and related species are illustrated. Observations of feeding habits and host plant of the larva are also provided.