Mythimna separata (Walker) (Lepidoptera: Noctuidae) is one of the most destructive phytophagous pests. Here we present detailed instructions to achieve successful application of CRISPR/Cas9‐mediated ...genome editing on M. separata. We optimized procedures, including egg collection and incubation. We further successfully conducted microinjection on the washed eggs by applying water on the egg surface. We then evaluated the effects of injection timing on both egg viability and genome editing efficiency using NPC1b as the target gene. We observed that Cas9 protein injection had significantly less effect on the viability of the eggs at the earlier stage (<2 h old) than at later stages, although no significant effect was observed on the postembryonic development between different egg ages. All larvae were edited when the eggs were <6 h old, and the editing efficiency decreased when older eggs were used. Moreover, mutants were detected among G1 progenies, which demonstrated that the mutation generated by the Cas9/sgRNAs system on M. separata was heritable. As far as we know, this is the first report of CRISPR/Cas9 for this important pest. The successful application of genome editing on M. separata is essential to understanding its biology and developing novel control methods.
Mythimna separata (Lepidoptera: Noctuidae) is an important agricultural pest. We report detailed instructions to achieve the application of CRISPR/Cas9–mediated genome editing on M. separata, including egg collection and incubation, embryo microinjection, and injection timing. This is the first report of CRISPR/Cas9‐mediated genome editing in M. separata, and the information is essential to conduct molecular research on the biology of this important pest.
Damage by herbivores often modifies plant structure and physiology, which may change the behaviour and performance of future herbivores. Here, we studied such interactions among the major coconut ...pest, the mite Aceria guerreronis (Acari: Eriophyidae), and two minor pests, the mite Steneotarsonemus concavuscutum (Acari: Tarsonemidae) and the moth Atheloca bondari (Lepidoptera: Pyralidae). All these species develop in the meristematic zone of coconuts, which is difficult to access because of the small opening between the epicarp and perianth. Both mites cause necrosis on the epicarp of the nuts, which may facilitate access to the meristematic zone by caterpillars of the moth. However, the caterpillars co‐occur predominantly with A. guerreronis and not with S. concavuscutum. We show that caterpillars did not colonize nuts without mites and colonized nuts with A. guerreronis most frequently, in agreement with the openings caused by this mite and caterpillar size. When the opening between epicarp and perianth was artificially increased, caterpillars also colonized nuts without mites and nuts with S. concavuscutum. When offered a choice, caterpillars preferred nuts with easy access to the meristematic region, regardless of the presence of mites. Caterpillars performed better on the A. guerreronis‐infested nuts than on other nuts, but moth females did not preferentially oviposit in coconut bunches infested with mites. Hence, caterpillars, not adults, select suitable feeding sites within a bunch of coconuts, and A. guerreronis facilitates the infestation of coconuts by A. bondari. We discuss how damage by mites affects the relevance of A. bondari as a coconut pest.
Commercial use of wildlife is booming. However, knowledge of trade, price structure and benefit distribution mechanisms remain limited for many endemic, threatened and economically valuable species, ...impeding efforts to develop conservation intervention schemes in line with sustainable objectives. We illustrate the nature of commercialization of the caterpillar fungus Ophiocordyceps sinensis, collected in a high-altitude Tibetan region. Using the value-chain approach, we document how caterpillar fungus is collected in a remote mountainous region and traded across a wide range of middlemen until it finally reaches high-end markets in urban centres. Mapping the caterpillar fungus value chain helps identify the actors involved and the social institutions (i.e. the rules, norms and arrangements that shape people's behaviours) facilitating access to markets and influencing profit distribution and price structure. We present the complex dynamics of this commercialization process, providing a holistic value-chain analysis that encompasses actors, profits and institutions.
Although wildlife trade has received considerable research and conservation attention, much of it has been focused on charismatic species, with taxa such as fungi receiving little or no attention ...despite being highly sought after. The caterpillar fungus Ophiocordyceps sinensis is highly valued as an ingredient in cosmetics and medicines, and as an aphrodisiac and dietary supplement. Despite its livelihood and socio-economic significance, it has received little attention in either research or wildlife trade policy. Nevertheless, trade appears to be rampant, and growing online, and this is an emerging conservation challenge. Here we present a systematic survey of online trade in the caterpillar fungus during 2021. During this period, 168 advertisements were recorded on eight e-commerce platforms, both national and international. The grade of the caterpillar fungus advertised for sale fell into six categories. Fungi described as pure/organic/wild grade, which we categorized as authentic grade, had the highest median price (24 USD/g) and those described as medicine/food/cosmetic/beverage, which we categorized as consumption grade, had the lowest median price (0.04 USD/g). The highest advertised sale price was for caterpillar fungus of Bhutan origin (155 USD/g) advertised on the eBay e-commerce platform. Trade in caterpillar fungus on national and international online platforms is evident, and trade in other non-charismatic species is also likely burgeoning online but remains poorly documented. Further systematic surveys of online trade are required, not only to improve understanding of such trade but also to facilitate the development of effective conservation interventions and prevent undocumented overexploitation of important natural resources in developing countries.
Insect–plant interactions are less well studied than other types of herbivory on islands, precluding a comprehensive understanding of the evolutionary ecology of these interactions. Declines in ...native island plants and insects call for urgent attention to characterize these species' interactions for their conservation and to better understand evolution in these unique, insular ecosystems. In Hawai‘i, the Kamehameha butterfly (Vanessa tameamea) is one of only two native butterflies, and larvae are specialists on native urticaceous plants. Using a no‐choice bioassay, we investigated performance of V. tameamea reared from egg hatching through eclosion on four native urticaceous host plants, Boehmeria grandis, Pipturus albidus, Touchardia latifolia, and Touchardia oahuensis, and one exotic urticaceous species, Cecropia obtusifolia. Performance varied significantly among the plant diets, with V. tameamea performing best on P. albidus and T. oahuensis among the performance metrics of survival, pupal and adult body mass, and development time. Larval responses to the exotic host plant C. obtusifolia varied among populations, with O‘ahu caterpillars successfully completing development on it, but Hawai‘i Island caterpillars rejecting it completely, suggesting a geographic mosaic for this novel species interaction. Characterization of a suite of nutritive and defensive plant traits revealed significant variability among plant species, but patterns did not align well with V. tameamea performance rankings, making it difficult to identify key drivers of host plant quality. Future work examining additional plant traits under natural conditions would provide new insights, contributing critical ecological information to conserve this charismatic island species.
The endemic Hawaiian Kamehameha butterfly is a specialist on Urticaceous host plants. Yet, caterpillar performance varies significantly among 4 native and 1 non‐native host plant. Potential defense and nutritive traits also vary among host plant species, but are not consistent with performance rankings, highlighting this as future research need.
Ophiocordyceps sinensis (Berk.) G.H.Sung, J.M.Sung, Hywel-Jones & Spatafora, a high altitude Himalayan fungus-caterpillar product found in alpine meadows in China, Bhutan, Nepal, and India, has been ...used in the Traditional Chinese Medicine system for over 2000 years. Heightened demand in China over the past 15 years, coupled with limited production, has led to a price hike and increased economic importance of harvests to rural households throughout the species’ range. There is, however, limited knowledge on the actors and profit distribution in the O. sinensis production network, especially from the distribution areas on the southern flanks of the Himalayas. Filling in this knowledge gap is essential to the identification and design of public interventions.
To describe and quantify the O. sinensis production network originating from Darchula District in far-western Nepal.
Data was collected, for fiscal year 2014–15, in spring and summer 2016 using standardized collector (n=56) and trader (n=45) questionnaires in Darchula District, and central wholesaler (n=9) questionnaires in cities of Nepal. All questionnaires contained quantitative and qualitative components focusing on key elements of the production network, i.e. value creation, enhancement, and capture; and network and territorial embeddedness.
Trade is sustained and significant even at the margins of the distributional range, with 384.1 kg of O. sinensis harvested in and traded from Darchula District in 2014–15, having a collector value of approximately USD 4.7 million and constituting the dominant household-level source of income for collectors. The functioning production network is characterised by conflicts in relation to value creation, a high share of value capture by collectors, limited value enhancement, and a high degree of network and territorial embeddedness.
O. sinensis income is of major economic importance for rural households at the margin of its distribution range in Nepal. Production networks operated by informal actors establishing trust-based relationships allow responses to cross-border market signals, enabling the flow of rural and remote environmental resources to urban centres of demand. There is scope for public interventions, e.g. to determine the drivers of demand.
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Compared with the single pin crawler, a double pin caterpillar platform has lower vibration and noise, which is widely used in tracked vehicles. However, its dynamical model is more complex due to ...its high degrees of freedom and laborious contact detection involved. It is significant to develop an accurate and efficient contact algorithm between tracks and wheels. In this paper, the profiles of the track connector and the tooth groove are discretized into several arc surfaces. The contact between them is characterized as convex and concave. Accordingly, a general mathematical description of the tooth profile is established to describe the real tooth groove geometry. Then a generalized cylindrical contact model is developed to evaluate forces. In the contact detection process, the local frames of the sprocket and tooth groove are employed, resulting in the vector quantities and coordinate transformations describing the contact arc surfaces constantly. This approach can facilitate programming and effectively improve calculation efficiency. Subsequently, a field test was performed to verify the correctness of the dynamical model. To reduce the wear of the sprocket, different cases are simulated, and a reasonable radius of the rubber ring is proposed.
We show that the symmetric function generalization of the chromatic polynomial, or equivalently, the U-polynomial, distinguishes among a large class of caterpillar trees that we call proper, thus ...improving previous results by Martin, Morin and Wagner.
Owing to the uprising health issues due to amine exposure, this work has been taken up to design a novel caterpillar-like ZnO nanoarchitecture using a combined hydrothermal and Forcespinning® ...technology for sensing amine vapor. This study presents two different approaches to investigate the sensing behavior of the caterpillar-like ZnO nanostructure compared to both commercially available ZnO nanoparticles and laboratory synthesized carbon/ZnO composite fibers. It is found that ZnO caterpillar-like nanostructure shows the best performance owing to its highest surface to volume ratio. Electrochemical investigations suggest maximum enhancement in current density from the caterpillar-like ZnO nanostructure on amine exposure due to the increased involvement of electron pair of nitrogen owing to its high hydroxyl concentration. Photoluminescence spectroscopy depicts defect induced blue emission owing to defect in native ZnO nanoparticles which quenches on amine exposure. The quenching has been found to be monotonic over the entire range of exposed n-propyl amine (NPA, 0–500 ppm) and attributed to defect annihilation upon exposing to amine vapor. Optical detection of NPA by the caterpillar-like ZnO nanostructure based on emission quenching shows a linear response in the studied NPA concentration range with a detection limit (LOD) of 12.54 ppm. Our results demonstrate the importance of structure, morphology and architecture of ZnO for gas sensing activity.
•Novel caterpillar-like ZnO nanostructure (CZN) was designed.•Sensing behavior of CZN was compared to commercial ZnO NPs and C/ZnO composite fibers.•Enhancement in current density of the caterpillar-like ZnO nanostructure on amine exposure.•Quenching of defect induced blue emission on amine exposure.•Linear response towards amine vapor in the range 0–500 ppm with detection limit of 12.5 ppm.
This work demonstrated enhanced sensitivity of caterpillar zinc nanostructure towards amine sensitivity Display omitted
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