The antennal transcriptome analysis and characterizations of odorant-binding proteins in Megachile saussurei (Hymenoptera, Megachilidae).

BACKGROUND: Odorant-binding proteins (OBPs) are essential in insect's daily behaviors mediated by olfactory perception. Megachile saussurei Radoszkowski (Hymenoptera, Megachilidae) is a principal insect pollinating alfalfa (Medicago sativa) in Northwestern China. The olfactory function have been less conducted, which provides a lot of possibilities for our research. RESULTS: Our results showed that 20 OBPs were identified in total. Multiple sequence alignment analysis indicated MsauOBPs were highly conserved with a 6-cysteine motif pattern and all belonged to the classic subfamily, coding 113-196 amino acids and sharing 41.32%-99.12% amino acid identity with known OBPs of other bees. Phylogenetic analysis indicated there were certain homologies existed among MsauOBPs and most sequences were clustered with that of Osmia cornuta (Hymenoptera, Megachilidae). Expression analysis showed the identified OBPs were mostly enriched in antennae instead of other four body parts, especially the MsauOBP2, MsauOBP3, MsauOBP4, MsauOBP8, MsauOBP11 and MsauOBP17, in which the MsauOBP2, MsauOBP4 and MsauOBP8 presented obvious tissue-biased expression pattern. Molecular docking results indicated MsauOBP4 might be the most significant protein in recognizing alfalfa flower volatile 3-Octanone, while MsauOBP13 might be the most crucial protein identifying (Z)-3-hexenyl acetate. It was also found the lysine was a momentous hydrophilic amino acid in docking simulations. CONCLUSION: In this study, we identified and analyzed 20 OBPs of M. saussurei. The certain homology existed among these OBPs, while some degree of divergence could also be noticed, indicating the complex functions that different MsauOBPs performed. Besides, the M. saussurei and Osmia cornuta were very likely to share similar physiological functions as most of their OBPs were clustered together. MsauOBP4 might be the key protein in recognizing 3-Octanone, while MsauOBP13 might be the key protein in binding (Z)-3-hexenyl acetate. These two proteins might contribute to the alfalfa-locating during the pollination process. The relevant results may help determine the highly specific and effective attractants for M. saussurei in alfalfa pollination and reveal the molecular mechanism of odor-evoked pollinating behavior between these two species.

Effects of Fusarium solani on the Growth and Development of Anoplophora glabripennis Larvae.

Anoplophora glabripennis (Asian longhorned beetle) is a wood-boring pest that can inhabit a wide range of healthy deciduous host trees in native and non-native habitats. Lignocellulose degradation plays a major role in the acquisition of nutrients during the growth and development of A. glabripennis larvae. In this study, the lignocellulose degradation capacity of Fusarium solani, a fungal symbiont of A. glabripennis, was investigated in fermentation culture and in four host tree species. The impact of F. solani on larval growth and survival parameters was assessed. Fermentation culture demonstrated continuous and stable production of lignocellulolytic enzymes over the cultivation period. Furthermore, F. solani was able to degrade host tree lignocellulose, as shown by decreased soluble sugar and cellulose contents and an increase in protein content. No significant differences in larval survival were observed in larvae fed with or without F. solani. However, weight and head capsule width were higher in larvae fed on F. solani, and gut lignocellulose activities were elevated in fed larvae. Our results indicate a role for F. solani in the predigestion of lignocellulose during the colonization and parasitic stages of A. glabripennis larval development, and also the F. solani an important symbiotic partner to A. glabripennis, lowering barriers to colonization and development in a range of habitats.

A rapid construction of new boron heterocycles and evaluation of photophysical properties of iminoboronates.

A green and efficient method for the synthesis of oxadiazaborole, dioxazaborinine, and oxadiazaborinine from the reactions of phenylboronic acid with amidoxime, α-hydroxyl oxime and α-hydroxyl hydrazone, respectively, is described. The reactions were performed under catalyst-free and mild conditions. All products can be rapidly purified by filtration and washing. In addition, a set of iminoboronates were prepared following a one-pot multicomponent reaction procedure using α-hydroxyl hydrazone, salicylaldehyde and boronic acid derivatives as starting materials and their photophysical properties were assessed. Then, cross-coupling reactions can be carried out smoothly on some target compounds, which may help develop new boron masking strategies.

Effects of B-azolemiteacrylic on life-history traits and demographic parameters of two-spotted spider mite, Tetranychus urticae (Acari: Tetranychidae).

The present study was conducted to evaluate sublethal effects of B-azolemiteacrylic on the two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae). Female adults of T. urticae were exposed to LC10 and LC30 of the acaricide, and the effects on treated females and their offspring were evaluated. The results showed that the fecundity of F0 female adults treated with LC10 and LC30 of B-azolemiteacrylic was reduced by 30.9 and 39.2%, respectively. Longevity and oviposition period of the females were significantly reduced as well. The developmental duration of egg and deutonymph stage of the F1 generation were not significantly different from that of the control. The protonymph stage after LC30 treatment lasted significantly longer, whereas the larva, deutonymph and female stage were significantly shorter than the control. The oviposition period of the F1 generation was significantly shortened, the fecundity of each female decreased significantly, and the ratio of female-to-male was reduced too. Moreover, the average generation period of T. urticae after LC10 and LC30 treatments was shorter than that of the control, and the net production rate (R0), intrinsic rate of increase (rm) and finite rate of increase (λ) were all reduced by 33.3, 7.5 and 1.9% (LC10 treatment) and by 51.3, 14.8 and 3.6% (LC30 treatment), respectively. The population doubling time was prolonged by 7.5 and 14.8% after LC10 and LC30 treatments, respectively, compared with the control. These results indicate that B-azolemiteacrylic may effectively inhibit the development rate of the F0 and F1 populations of T. urticae, which will help design integrated strategies for the comprehensive control of T. urticae and rational use of pesticides in the field.

Michael Addition Reaction Catalyzed by Imidazolium Chloride to Protect Amino Groups and Construct Medium Ring Heterocycles.

An effective approach for amino protection and construction of a seven-membered ring has been developed. The method uses imidazolium chloride to carry out the Michael addition reaction at low temperatures and perform amino deprotection or construction of a seven-membered ring at high temperatures.

Halogen-Metal Exchange on Bromoheterocyclics with Substituents Containing an Acidic Proton via Formation of a Magnesium Intermediate.

A selective and practical bromine-metal exchange on bromoheterocyclics bearing substituents with an acidic proton under non-cryogenic conditions was developed by a simple modification of an existing protocol. Our protocol of using a combination of i-PrMgCl and n-BuLi has not only solved the problem of intermolecular quenching that often occurred when using alkyl lithium alone as the reagent for halogen-lithium exchange, but also offered a highly selective method for performing bromo-metal exchange on dibrominated arene compounds through chelation effect.

Effectiveness of 12 Insecticides to a Laboratory Population of Cydia pomonella (Lepidoptera: Tortricidae) Newly Established in China.

The codling moth Cydia pomonella (L.) is an economically important fruit pest that has spread rapidly from its original site in Xinjiang to other northwestern regions of China. Insecticides are widely used to control this pest but its invasion has never been completely stopped. The aim of this study was to establish a laboratory population of the codling moth occurring in China, to investigate the effectiveness of 12 conventional insecticides to this laboratory population, and to recommend the discriminating doses for use in resistance monitoring. The laboratory population was generally similar to other laboratory strains although parameters such as survival rate and larval duration were low when compared with field populations. Toxicity varied among the insecticides tested with LC50 values ranging from 0.016 mg/l for emamectin benzoate to 55.77 mg/l for chlorbenzuron. Discriminating dose levels were determined from dose-mortality reference curves for the detection of resistance in field populations. Effectiveness of 12 insecticides to a laboratory population of codling moth in China was evaluated for the first time. This can be integrated into resistance management strategies, especially in orchards with a history of frequent insecticides applications, in order to monitor or decrease insecticide resistance in the future.

Glutathione S-Transferase Genes Involved in Response to Short-Term Heat Stress in Tetranychus urticae (Koch).

Tetranychus urticae, a globally ubiquitous mite, poses a significant threat to agriculture. Elevated temperatures exacerbate the growth, development, and reproduction of T. urticae, leading to substantial crop damage. In this study, we employed comparative transcriptomic approaches with whole-genome information of T. urticae to identify six Glutathione S-transferase genes (GSTs) implicated in heat stress response. Through comprehensive bioinformatics analyses, we elucidated the tertiary structure and active sites of the corresponding proteins, providing a thorough characterization of these GST genes. Furthermore, we investigated the expression patterns of these six GST genes under short-term heat shock conditions. Our findings unveiled the involvement of T. urticae GST genes in combating oxidative stress induced by heat, underscoring their role in antioxidant defense mechanisms. This study contributes valuable insights into the molecular mechanisms underlying the response of T. urticae to heat stress, laying a foundation for the development of strategies aimed at mitigating its impact in high-temperature environments.

Ozone Application Suppressed the Blue Mold Development and Maintained the Main Active Ingredients Content of Postharvest Fresh Codonopsis pilosula during Storage.

Penicillium expansum is the predominant causal agent causing blue mold in postharvest fresh Codonopsis pilosula during storage. The pathogen reduces the yield and affects the quality of C. pilosula and even generates patulin, threatening human health. In this study, postharvest fresh, healthy C. pilosula was sprayed with P. expansum, and the control effect of ozone on postharvest diseases of C. pilosula was studied, and the effect of ozone on the contents in the main active ingredients of C. pilosula was compared; finally, the effect of ozone on reactive oxygen species (ROS) metabolism in C. pilosula was analyzed. The results showed that 2 mg L-1 ozone application significantly inhibited the occurrence of postharvest blue mold caused by P. expansum, reduced weight loss rate, controlled the accumulation of patulin and maintained the contents of the main active components in C. pilosula. The study will provide a theoretical basis for ozone treatment to control the occurrence of postharvest diseases of C. pilosula.

Antennal Transcriptome Evaluation and Analysis for Odorant-Binding Proteins, Chemosensory Proteins, and Suitable Reference Genes in the Leaf Beetle Pest Diorhabda rybakowi Weise (Coleoptera: Chrysomelidae).

Diorhabda rybakowi Weise is one of the dominant pests feeding on Nitraria spp., a pioneer plant used for windbreaking and sand fixation purposes, and poses a threat to local livestock and ecosystems. To clarify the key olfactory genes of D. rybakowi and provide a theoretical basis for attractant and repellent development, the optimal reference genes under two different conditions (tissue and sex) were identified, and the bioinformatics and characterization of the tissue expression profiles of two categories of soluble olfactory proteins (OBPs and CSPs) were investigated. The results showed that the best reference genes were RPL13a and RPS18 for comparison among tissues, and RPL19 and RPS18 for comparison between sexes. Strong expressions of DrybOBP3, DrybOBP6, DrybOBP7, DrybOBP10, DrybOBP11, DrybCSP2, and DrybCSP5 were found in antennae, the most important olfactory organ for D. rybakowi. These findings not only provide a basis for further in-depth research on the olfactory molecular mechanisms of host-specialized pests but also provide a theoretical basis for the future development of new chemical attractants or repellents using volatiles to control D. rybakowi.

Isolation of the Main Pathogens Causing Postharvest Disease in Fresh Angelica sinensis during Different Storage Stages and Impacts of Ozone Treatment on Disease Development and Mycotoxin Production.

Angelica sinensis, a Chinese herbal medicine, is susceptible to molds during storage, reducing its quality, and even generating mycotoxins with toxic effects on human health. Fresh A. sinensis was harvested from Min County of Gansu Province in China and kept at room temperature. Naturally occurring symptoms were observed during different storage stages. Molds were isolated and identified from the diseased A. sinensis using morphological and molecular biology methods. The impact of ozone treatment on postharvest disease development and mycotoxin production was investigated. The results indicated that A. sinensis decay began on day 7 of storage and progressed thereafter. Nine mold species were isolated and characterized: day 7, two Mucormycetes; day 14, Clonostachys rosea; day 21, two Penicillium species and Aspergillus versicolor; day 28, Alternaria alternata and Trichoderma atroviride; and day 49, Fusarium solani. Ozone treatment markedly inhibited the development of postharvest disease and the mycotoxin production (such as, patulin, 15-acetyl-deoxynivalenol, and sterigmatocystin) in the rotten tissue of A. sinensis inoculated with the nine isolates.

Isolation of Main Pathogens Causing Postharvest Disease in Fresh Codonopsis pilosula during Different Storage Stages and Ozone Control against Disease and Mycotoxin Accumulation.

Codonopsis pilosula is an important Chinese herbal medicine. However, fresh C. pilosula is prone to decay during storage due to microorganism infections, seriously affecting the medicinal value and even causing mycotoxin accumulation. Therefore, it is necessary to study the pathogens present and develop efficient control strategies to mitigate their detrimental effects on the herbs during storage. In this study, fresh C. pilosula was collected from Min County in Gansu Province, China. The natural disease symptoms were observed during different storage stages, and the pathogens causing C. pilosula postharvest decay were isolated from the infected fresh C. pilosula. Morphological and molecular identification were performed, and pathogenicity was tested using Koch's postulates. In addition, the control of ozone was examined against the isolates and mycotoxin accumulation. The results indicated that the naturally occurring symptom increased progressively with the extension of storage time. The mucor rot caused by Mucor was first observed on day 7, followed by root rot caused by Fusarium on day 14. Blue mold disease caused by Penicillum expansum was detected as the most serious postharvest disease on day 28. Pink rot disease caused by Trichothecium roseum was observed on day 56. Moreover, ozone treatment significantly decreased the development of postharvest disease and inhibited the accumulations of patulin, deoxynivalenol, 15-Acetyl-deoxynivalenol, and HT-2 toxin.

Elucidating the Effect of Temperature Stress on the Protein Content, Total Antioxidant Capacity, and Antioxidant Enzyme Activities in Tetranychus urticae (Acari: Tetranychidae).

Tetranychus urticae Koch is a worldwide agricultural pest mite that feeds on more than 1100 kinds of crops. The mite has developed a high level of tolerance to high temperatures, but the physiological mechanism underlying the outstanding adaptability of this pest to high temperatures remains unclear. To clarify the physiological mechanisms of T. urticae in response to short-term heat stress, four temperatures (36, 39, 42, and 45 °C) and three short-term heat durations (2, 4, and 6 h) were conducted to test the effects on protein content, the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), and the total antioxidant capacity (T-AOC). The results showed that protein content, antioxidant enzyme activity, and T-AOC in T. urticae were significantly induced by heat stress. These results suggest that heat stress induces oxidative stress and that antioxidant enzymes play an important role in reducing oxidative damage in T. urticae. The data of this study will provide a basis for further research on the molecular mechanisms of thermostability and ecological adaptability of T. urticae.

Selection, Identification, and Transcript Expression Analysis of Antioxidant Enzyme Genes in Neoseiulus barkeri after Short-Term Heat Stress.

Phytoseiid mite Neoseiulus barkeri is a crucial biological control agent utilized to control pest mites and many insects in crops all over the world. However, they are vulnerable to multiple environmental pressures, with high-temperature stress being the most significant challenge. Heat stress disrupts the balance of reactive oxygen species (ROS) levels in organisms, resulting in oxidative stress within the body. Antioxidant enzymes play a crucial role in effectively neutralizing and clearing ROS. In this study, comparative transcriptomics and quantitative real-time PCR (qRT-PCR) were employed to assess the impact of short-term heat stress on the transcript expression of antioxidant enzyme genes in N. barkeri. We primarily identified four antioxidant enzyme genes (NbSOD, NbPrx, NbCAT, and NbGPX) in N. barkeri after exposure to short-term heat stress. Then, new data on the expression patterns of these genes were generated. RNA sequencing and bioinformatics analysis revealed that NbSOD belongs to the Fe/Mn family of superoxide dismutase (SOD), which was identified as MnSOD. NbPrx was classified as a 1-Cys peroxiredoxin of the peroxidase family, whereas NbCAT was recognized as a classical catalase, and NbGPX was determined as cytoplasmic glutathione peroxidase-1 (GPX1). Transcriptional expression analysis of these four genes was conducted at different high temperatures: 36 °C, 38 °C, and 40 °C for 2, 4, and 6 h. The results also showed that all four genes exhibited significant up-regulation in response to short-term heat stress. Similarly, the highest expression levels for NbSOD, NbPrx, and NbCAT were observed at 40 °C for 4 h. However, NbGPX displayed its maximum expression value at 38 °C for 4 h. Overall, the obtained data suggest that short-term heat stress increases levels of ROS generated inside living organisms, which disrupts the oxidative balance and leads to alterations in the expression levels of antioxidant enzyme genes.

Effects of short-term heat stress on the activity of three antioxidant enzymes of predatory mite Neoseiulus barkeri (acari, phytoseiidae).

To study the physiological mechanisms of Neoseiulus barkeri in response to short-term heat stress, the eggs and the emerged adults were exposed to 38, 40, and 42°C, 85% ± 5%RH,16 h:8 h (L:D) for 2, 4, and 6 h. The activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) as well as the protein content of N. barkeri were examined. All treatments caused significant different changes compared to the untreated control. The protein content increased as the temperature increased, while it showed different changing trends with the prolongation of exposure duration. The enzymatic activity of SOD, CAT, and POD was significantly affected by the temperature treatment. Both the maximum and minimum level of the three enzymes after a short-term heat stress differed significantly to the control group (p < 0.05). The highest values of three enzymatic activities were all obtained at 40°C-4 h. Person correlation analysis indicates that the high temperature was the primary factor affecting the enzymatic activity, while the exposure duration of the heat stress was the secondary factor. In general, the short-term heat stress increased the protein content of Neoseiulus barkeri and up-regulated the expression of SOD, CAT, and POD activities as well.

Gut Lignocellulose Activity and Microbiota in Asian Longhorned Beetle and Their Predicted Contribution to Larval Nutrition.

Anoplophora glabripennis (Asian longhorned beetle) is a wood-boring pest that can inhabit a wide range of healthy deciduous host trees in native and invaded areas. The gut microbiota plays important roles in the acquisition of nutrients for the growth and development of A. glabripennis larvae. Herein, we investigated the larval gut structure and studied the lignocellulose activity and microbial communities of the larval gut following feeding on different host trees. The larval gut was divided into foregut, midgut, and hindgut, of which the midgut is the longest, forming a single loop under itself. Microbial community composition and lignocellulose activity in larval gut extracts were correlated with host tree species. A. glabripennis larvae fed on the preferred host (Populus gansuensis) had higher lignocellulose activity and microbial diversity than larvae reared on either a secondary host (Salix babylonica) or a resistant host (Populus alba var. pyramidalis). Wolbachia was the most dominant bacteria in the gut of larvae fed on S. babylonica and P. alba var. pyramidalis, while Enterococcus and Gibbsiella were the most dominant in larvae fed on P. gansuensis, followed by Wolbachia. The lignocellulose-degrading fungus Fusarium solani was dominant in the larval gut fed on different host trees. Functional predictions of microbial communities in the larval gut fed on different resistant host trees suggested that they all play a role in degrading lignocellulose, detoxification, and fixing nitrogen, which likely contribute to the ability of these larvae to thrive in a broad range of host tree species.

Imidazole Hydrochloride Promoted Synthesis of Nitriles from Aldehydes.

BACKGROUND AND OBJECTIVE: As a key pharmacophore, the cyano group widely exists in a variety of biologically active compounds. Besides, nitriles are also valuable intermediates for many common functional groups. In this current work, a new synthesis strategy was developed to obtain nitriles from aldehydes. METHODS: Using commercially available aldehydes as raw materials, and hydroxylamine and hydrochloride as nitrogen sources, the corresponding nitrile compounds were successfully synthesized by the one-pot method through the promotion of imidazole hydrochloride. And it was characterized by 1H NMR, 13C NMR, and mass spectrometry. RESULTS: Various reaction conditions were applied in order to find an optimum and convenient procedure for the formation of nitriles. The highest yields (95%) were achieved using sulfolane as a solvent, and imidazole hydrochloride as a promoter. CONCLUSION: In conclusion, we developed a new synthetic method for nitrile compounds from aldehydes. Twenty seven examples of functionalized nitrile compounds have been synthesized in good to excellent yields. This methodology features that an environmentally benign imidazole hydrochloride replaces transition metal catalysts and oxidants required in conventional strategies to convert aldehydes into nitriles with good functional group tolerability. Further exploration of imidazole hydrochloride is ongoing in our laboratory.

Review of the Pacific leafhopper genus Hecaloidella (Hemiptera: Cicadellidae: Deltocephalinae: Selenocephalini) with description of sixteen new species.

Eighteen species of the Pacific leafhopper genus Hecaloidella Osborn, 1934 are described and illustrated and a key provided for their separation. The previously described species, H. nitida Osborn (type species) and H. brunnifacialis Shang Zhang, and the following sixteen new species are treated: H. brunifasciata Zhang Webb, H. bimaculata Zhang Webb, H. borneoensis Zhang Webb, H. brevis Zhang Webb, H. brevipenis Zhang Webb, H. brevispina Zhang Webb, H. caudospina Zhang Webb, H. knighti Zhang Webb, H. longipenis Zhang Webb, H. nudapenis Zhang Webb, H. pacifica Zhang Webb, H. quadripicta Zhang Webb, H. quadrispina Zhang Webb, H. sandakanensis Zhang Webb, H. singaporensis Zhang Webb and H. spinosa Zhang Webb spp. nov..

The Effects of Vegetation Type on Oedaleus decorus asiaticus (Orthoptera: Acrididae) Oviposition and Hatching Success.

Oedaleus decorus asiaticus (Bei-Bienko, 1941) has been regarded as one of the most dominant locusts in the northern grassland, the adjacent area of agriculture and animal farmland, in China. The aims of this study were to investigate the effects of vegetation type on the oviposition behavior of this pest in an open field and the hatching success of the offspring in the following year. The results showed that vegetation type did have a significant effect on whether any egg pods were laid by O. d. asiaticus. Once the females laid eggs, vegetation type and cage number had a significant effect on the number of egg pods laid. The highest number of egg pods was found in the Cleistogenes squarrosa treatment, followed by Stipa krylovii and then Leymus chinensis, while the Artemisia frigida treatment contained the lowest number of egg pods. The O. d. asiaticus eggs laid in S. krylovii and C. squarrosa treatments had a significantly higher hatching success rate (over 53%) than the other two grasses (below 40%). In short, habitats with C. squarrosa and S. krylovii grasses are likely to be preferred by ovipositing females, thus population monitoring efforts of O. d. asiaticus should focus on these habitats.

[Butterfly diversity and faunal characteristics on the south slope of Taibai Mountain, Shaanxi Province of Northwest China].

An investigation was conducted on the butterflies on the south slope of Taibai Mountain from April to October, 2009, with their diversity index, evenness index, dominance index, and species richness calculated and analyzed. A total of 126 species were recorded, belonging to 77 genera and 5 families. Nymphalidae had the highest diversity index (3.3621) and species richness (9.9363), and Pieridae had the highest dominance index (0.0573) and evenness index (0.8352). The genera and species were most abundant in June-August, the diversity index was the highest in July (3.4094), and the species richness was the highest in August (10.7). The bio-geographic component analysis of 124 species (other 2 species were not identified) showed that the widely distributed species were most abundant (51 species), occupying 40.5% of the total, followed by Palaearctic species (41 species), occupying 32.5%, and Oriental species were the least (32 species), occupying 25.4%, which suggested that Taibai Mountain could be the transitional area of Palearctic and Oriental regions. The comparative analysis of the butterfly diversity and faunal characteristics on the south and north slopes of Taibai Mountain showed that there were 85 shared species, and the similarity coefficient was 62.0%, indicating that the butterfly fauna had definite difference between the two slopes though they were geographically in proximity.