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Tup1, a conserved transcriptional repressor, plays a critical role in the growth and development of fungi. Here, we identified a BsTup1 gene from the plant pathogenic fungus Bipolaris sorokiniana. The expression of BsTup1 showed a more than three-fold increase during the conidial stage compared with mycelium stage. Deletion of BsTup1 led to decrease hyphal growth and defect in conidia formation. A significant difference was detected in osmotic, oxidative, or cell wall stress responses between the WT and ΔBsTup1 strains. Pathogenicity assays showed that virulence of the ΔBsTup1 mutant was dramatically decreased on wheat and barely leaves. Moreover, it was observed that hyphal tips of the mutants could not form appressorium-like structures on the inner epidermis of onion and barley coleoptile. Yeast two-hybrid assays indicated that BsTup1 could interact with the BsSsn6. RNAseq revealed significant transcriptional changes in the ΔBsTup1 mutant with 2369 genes down-regulated and 2962 genes up-regulated. In these genes, we found that a subset of genes involved in fungal growth, sporulation, cell wall integrity, osmotic stress, oxidation stress, and pathogenicity, which were misregulated in the ΔBsTup1 mutant. These data revealed that BsTup1 has multiple functions in fungal growth, development, stress response and pathogenesis in B. sorokiniana.

The mechanism of sex pheromone reception in the male cotton bollworm Helicoverpa armigera has been extensively studied because it has become an important model system for understanding insect olfaction. However, the pathways of pheromone processing from the antenna to the primary olfactory center in H. armigera have not yet been clarified. Here, the physiology and morphology of male H. armigera olfactory sensory neurons (OSNs) were studied using single sensillum recording along with anterograde filling and intracellular recording with retrograde filling. OSNs localized in type A sensilla responded to the major pheromone component cis-11-hexadecenal, and the axonal terminals projected to the cumulus (Cu) of the macroglomerular complex (MGC). The OSNs in type B sensilla responded to the behavioral antagonist cis-9-tetradecenal, and the axonal terminals projected to the dorsomedial anterior (DMA) unit of the MGC. In type C sensilla, there were 2 OSNs: one that responded to cis-9-tetradecenal and cis-11-hexadecenol with the axonal terminals projecting to the DMA, and another that responded to the secondary pheromone components cis-9-hexadecenal and cis-9-tetradecenal with the axonal terminals projecting to the dorsomedial posterior (DMP) unit of the MGC. Type A and type B sensilla also housed the secondary OSNs, which were silent neurons with axonal terminals projected to the glomerulus G49 and DMP. Overall, the neural pathways that carry information on attractiveness and aversiveness in response to female pheromone components in H. armigera exhibit distinct projections to the MGC units.

The genus Phyllomyza Fallen is recorded from Laos for the first time with the following three species which are described as new to science: P. latusipalpis sp. nov., P. orbita sp. nov., and P. ver...

The genus Cryptochetum Rondani is recorded from Vietnam for the first time with three species described and figured as new to science: C. dicranumsp. nov., C. equitanumsp. nov., and C. proceripalpissp. nov. A key to the species of the genus from Vietnam is presented.

Four new species of the Phyllomyza Fallen (Diptera: Milichiidae) from China are reported from Tibet. The following four species are described as new to science: Phyllomyza flavipes sp. nov., Phyllomyza motuoensis sp. nov., Phyllomyza prolongatusa sp. nov. and Phyllomyza striolatum sp. nov. A key to the known species of Phyllomyza from China is presented. The type specimens of the new species are deposited in the Henan Agricultural University.

The following three species of the genus Phyllomyza Fallén from China are described as new to science: P.guangxiensis sp. n., P.luteigenis sp. n., and P.quadratpalpus sp. n. A key to the known species of Phyllomyza from China is presented.

Three new species of the genusNeophyllomyza,N.clavipalpissp. nov.,N.motuoensissp. nov., andN.obtusasp. nov., are described from China. A revised key to the six Chinese species ofNeophyllomyzais also presented.

Although lysis of invading organisms is a major innate form of immunity used by invertebrates, it remains unclear whether herbivorous insects have hemolysin or not. To address this general question, we tested the hemolytic (HL) activity of the hemolymph and tissue extracts from various stages of the polyphagous insect Helicoverpa armigera (Hubner) against the erythrocytes from chicken, duck, and rabbit. An HL activity was identified in the hemolymph of H. armigera larvae. Further studies demonstrated that the HL activity is proteinaceous as it was precipitable by deproteinizing agents. Hemolysins were found in Helicoverpa egg, larva, pupa, and adult, but the activity was higher in feeding larvae than in molting or newly molted larvae. Hemolysins were distributed among a variety of larval tissues including salivary gland, fat body, epidermis, midgut, or testes, but the highest activity was found in salivary gland and fat body. Relative to nonparasitized larvae, parasitization of H. armigera larvae by the endoparasitoid Campoletis chlorideae Uchida induced a 3.4-fold increase in the HL activity in the plasma of parasitized host at day two postparasitization. The present study shows the presence of a parasitoid inducible HL factor in the parasitized insect. The HL activity increased significantly in H. armigera larvae at 12 and 24 h postinjection with Escherichia coli. We infer the HL factor(s) is inducible or due to de novo synthesis, which means that the HL factor(s) is associated with insect immune response by inhibiting or clearance of invading organisms.

The C-type lectins mediate nonself recognition in insects. The previous studies focused on host immunlectin response to bacterial infection; however, the molecular basis of immunlectin reactions to endoparasitoids has not been elucidated. The present study investigated the effect of parasitization by Campoletis chlorideae on hemagglutination activity (HA; defined as the ability of lectin to agglutinate erythrocytes or other cells), and transcriptional expression of C-type immunlectin genes in the larval host, Helicoverpa armigera. Parasitization induced four- to eightfold higher HA in the parasitized larvae, compared to nonparasitized larvae at days 2 and 6 postparasitization (PP), however inhibited HA at other days PP. Eight C-type lectins were differentially expressed in different host developmental stages, from feeding to wandering stage. The mRNA levels of HaCTL1, HaCTL3, HaCTL4, and HaCTL5 were upregulated and HaCTL2 and HaCTL7 were downregulated. Tissue analysis showed that HaCTLs were mainly expressed in fat body or hemocytes, while HaCTL5 was highly expressed in testes. The effects of parasitization on the lectin expression patterns differed. Lectins except HaCTL6 or HaCTL5 were significantly down- or upregulated in parasitized larvae at day 4 or 6 PP compared with that of nonparasitized larvae. We infer from our results that C-type immunlectins are involved in host-parasitoid interactions, and parasitization alter host immunlectin levels both in inhibiting and promoting host immune defenses to endoparasitoids. These immunlectin genes indicated an altered physiological status of the host insect, depending on developmental stage, tissue, and parasitization.

Ooencyrtus phongi (Hymenoptera: Encyrtidae) is an important egg parasitoid of the litchi stink bug, Tessaratoma papillosa (Drury) (Hemiptera: Tessaratomidae). Antennae of parasitic Hymenoptera are important sensory organs and play an important role in host location, host discrimination, courtship, and mating behavior. In this article, we examined the external morphology of the antennal sensilla of female and male of O. phongi using scanning electron microscopy. Twelve morphological sensillar types were recognized in both sexes, including the placoid sensilla, basiconic sensilla, two types of sensilla trichodea, and eight types of sensilla chaetica. Major differences were found between the sexes, in number, distribution, shape, structure, and size of the identified sensilla. These results are discussed in relation to the possible role of these sensilla in the host location behavior of O. phongi.

Species of Astymachus and Boucekiella from China reviewed, with two new records namely, Astymachus japonicus and Boucekiella depressa. A new species, Boucekiella orientalis is described. The specimens are deposited with Institute of Zoology, Chinese Academy of Sciences, Beijing (IZCAS).

Although lysis of invading organisms is a major innate form of immunity used by invertebrates, it remains unclear whether herbivorous insects have hemolysin or not. To address this general question, we tested the hemolytic (HL) activity of the hemolymph and tissue extracts from various stages of the polyphagous insect Helicoverpa armigera (Hübner) against the erythrocytes from chicken, duck, and rabbit. An HL activity was identified in the hemolymph of H. armigera larvae. Further studies demonstrated that the HL activity is proteinaceous as it was precipitable by deproteinizing agents. Hemolysins were found in Helicoverpa egg, larva, pupa, and adult, but the activity was higher in feeding larvae than in molting or newly molted larvae. Hemolysins were distributed among a variety of larval tissues including salivary gland, fat body, epidermis, midgut, or testes, but the highest activity was found in salivary gland and fat body. Relative to nonparasitized larvae, parasitization of H. armigera larvae by the endoparasitoid Campoletis chlorideae Uchida induced a 3.4-fold increase in the HL activity in the plasma of parasitized host at day two postparasitization. The present study shows the presence of a parasitoid inducible HL factor in the parasitized insect. The HL activity increased significantly in H. armigera larvae at 12 and 24 h postinjection with Escherichia coli. We infer the HL factor(s) is inducible or due to de novo synthesis, which means that the HL factor(s) is associated with insect immune response by inhibiting or clearance of invading organisms.

Open reading frame 60 of Bombyx mori nucleopolyhedrovirus (Bm60) is located between 56,673 and 57,479 bp in the BmNPV genome which encodes 268 amino acid residues with predicted molecular weight of 31.0 kDa. Bm60 and its homologues have been identified in 11 completely sequenced lepidopteran NPVs. The transcript of Bm60 was detected by RT-PCR at 18-72 h post-infection (p.i.), while the corresponding protein could be detected at 24-72 h p.i. in BmNPV-infected BmN cells by Western blot analysis using a polyclonal antibody against Bm60. The expression of Bm60 was inhibited in the presence of Ara-c, an inhibitor of viral DNA synthesis. These results together indicated that Bm60 was a late gene. The size of Bm60 product was found to be a 31 kDa in BmNPV-infected BmN cells, consistent with predicted molecular weight. Immunofluoresence analysis showed that the Bm60 product was first detected in the cytoplasm at 24 h p.i and also located in nucleus during later infection. In conclusion, the available data suggest that Bm60 is a functional ORF of BmNPV and encodes a 31kDa protein expressed in the later stage of infection cycle.

Autographa californica nucleopolyhedrovirus orf74 (Ac74) is located between 62 311 and 63 108bp in the AcMNPV genome, which encodes 265 amino acid residues with a predicted 31 kDa molecular weight. The homologues of Ac74 were searched using BLASTP in protein databases, GenBank/EMBL and SWISS-PROT. The result revealed that deduced Ac74 protein was homologous to the predicted products from 10 lepidoptera NPV ORFs. The multiple sequence alignments of Ac74 and its 10 homologues manifested only one amino acid residue was completely conserved. The transcript analysis revealed that the transcript of Ac74 was detected from 24–72 hours post-infection (hpi). The product of Ac74 was detected at 24 hpi and lasted until 72 hpi by Western blot using anti-Ac74 antiserum, consistent with reverse transcriptase polymerase chain reaction results. These results suggested Ac74 was expressed during the later stages of infection. The product of Ac74 was 31 kDa in size, consistent with predicted molecular weight. The subcellular localization of Ac74 proteins manifested Ac74 protein in the cytoplasm, and was hardly present in the nucleus at 24 hpi. The fluorescence was also observed in polyhedra, except cytoplasm at 72 hpi. Together, Ac74 is a functional protein with 3 1kDa molecular weight and is located in the cytoplasm and the polyhedra.

Mating and oviposition rhythms and evidence for sex-specific pheromones of the gray-black citrus longicorn beetle Nadezhdiella cantori were investigated. The reproductive and flight activities of this insect mainly occurred between 1700 and 2400 h, and each activity had two peaks with the first one taking place within the 3 h before sunset (2100 h) and the second occurring within the 3 h after sunset. Circadian rhythms of mating and oviposition were significantly correlated but neither mating nor oviposition was significantly correlated with flight. It is suggested that mating and oviposition repeat in turn during pair-bonding and that flight is an indication of termination of reproductive activities in some individuals of a population. Males differentiated between sexes by touching. Mating behavior of males was stimulated by a contact female sex pheromone on the female body surface. Fighting behavior of males was mediated by a chemical on the male body surface. Females left trails of the contact sex pheromone on the trees when walking, which males used to locate them. Implications of these findings are discussed.

The C-type lectins mediate nonself recognition in insects. The previous studies focused on host immunlectin response to bacterial infection; however, the molecular basis of immunlectin reactions to endoparasitoids has not been elucidated. The present study investigated the effect of parasitization by Campoletis chlorideae on hemagglutination activity (HA; defined as the ability of lectin to agglutinate erythrocytes or other cells), and transcriptional expression of C-type immunlectin genes in the larval host, Helicoverpa armigera. Parasitization induced four- to eightfold higher HA in the parasitized larvae, compared to nonparasitized larvae at days 2 and 6 postparasitization (PP), however inhibited HA at other days PP. Eight C-type lectins were differentially expressed in different host developmental stages, from feeding to wandering stage. The mRNA levels of HaCTL1, HaCTL3, HaCTL4, and HaCTL5 were upregulated and HaCTL2 and HaCTL7 were downregulated. Tissue analysis showed that HaCTLs were mainly expressed in fat body or hemocytes, while HaCTL5 was highly expressed in testes. The effects of parasitization on the lectin expression patterns differed. Lectins except HaCTL6 or HaCTL5 were significantly down- or upregulated in parasitized larvae at day 4 or 6 PP compared with that of nonparasitized larvae. We infer from our results that C-type immunlectins are involved in host-parasitoid interactions, and parasitization alter host immunlectin levels both in inhibiting and promoting host immune defenses to endoparasitoids. These immunlectin genes indicated an altered physiological status of the host insect, depending on developmental stage, tissue, and parasitization.

Cytoplasmic lipid droplet (LD) lipolysis is regulated by pheromone biosynthesis activating neuropeptide (PBAN) in Bombyx mori. To elucidate the molecular mechanism of cytoplasm LD lipolysis, the pancreatic lipase-like gene in B. mori pheromone glands (PGs), designated as B. mori pancreatic lipase-like gene (BmPLLG), was identified in this study. Spatial expression analysis revealed that BmPLLG is a ubiquitous gene present in all studied tissues, such as PGs, brain, epidermis, egg, midgut, flight muscle and fat body. Temporal expression analysis showed that the BmPLLG transcript begins to express 96 h before eclosion (-96 h), continues to increase, peaks in newly emerged females and steadily decreases after eclosion. Translational expression analysis of BmPLLG using a prepared antiserum demonstrated that BmPLLG was expressed in an age-dependent pattern at different development stages in B. mori. This finding was similar to the transcript expression pattern. Further RNA interference-mediated knockdown of BmPLLG significantly inhibited bombykol production. Overall, these results demonstrated that BmPLLG is involved in PBAN-induced sex pheromone biosynthesis and release.

Sexual behavior between males and females, as well as between males, is described and discussed for the cerambycid beetlePhytoecia rufiventris. The beetles' taxis toward plants taller than average height brings the sexes together from a distance. A male may mount another individual (male or female) and attempt copulation without sex discrimination. The male can discern the sex of another individual only when the terminal part of his abdomen touches the ventral surface of the fifth visible sternite of the latter. No evidence of a sex pheromone is found in this species. Within 1.5–5.5 cm the substrateborne vibrations produced by a moving individual may be the important factor which elicits males to approach a moving individual and attempt copulation. If a female is receptive when a male touches her, he can copulate with her without any courtship display. However, if the female runs away and appears unreceptive, the male will perform courtship displays. Copulation is usually terminated by males. Homosexual behavior between males is discussed.

Observations and analytical experiments were conducted on the key factors that stimulated males of Paraglenea fortunei Saunders to approach females and attempt copulation. It is suggested that vision, stridulation, and palpi do not play a primary role in stimulating male sexual activity. The key stimulus that triggers male response is a female sex pheromone. This is air-borne and effective only within a range of about 3 cm. The main olfactory receptors for the female sex pheromone are situated in the male's antennae; a few receptors were found in other undetermined parts of the body.

The genus Raphignathus from China is reviewed. The morphology of R. zhaoi Hu, Jing & Liang is studied. Four new species of Raphignathus are described: R. aciculatus Fan from moss in Fujian (southeastern China), R. membranus Fan from fallen leaves in Beijing (north China), R. evidus Fan from moss in Beijing and R. hsiufui Fan from moss in Fujian and from tea (Camellia sinensis) in Zhejiang adjecent to Fujian. A key to the known species from China is provided.