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Minerals in edible insects:a review of content and potential for sustainable sourcing
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作者 Mingxing Lu Chenxu Zhu +4 位作者 Sergiy Smetana Ming Zhao Haibo Zhang Fang Zhang Yuzhou Du 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期65-74,共10页
In response to the rapid increase in world population and subsequent demands for food,edible insects represent an alternative food source for humans that is rich in proteins,amino acids and minerals.Entomophagy is a t... In response to the rapid increase in world population and subsequent demands for food,edible insects represent an alternative food source for humans that is rich in proteins,amino acids and minerals.Entomophagy is a tradition in many countries including China and Thailand,and edible insects have attracted a lot of attention in Western World due to their suitable nutrient composition,high mineral content(e.g.,Fe,Zn,Ca,Mg)and potential use as a supplement in human diet.In this study,we surveyed mineral content in seven insect orders and 67 species of mass produced and wild-harvested edible insects.The total content of essential elements in edible insects was very high in Tenebrio molitor,Bombyx mori,and Zonocerus variegatus.The heavy metal content(summarized for eight species)was below the maximum limit allowed for safe consumption.Sustainable supply of minerals derived from insect biomass is complicated due to the high variations of mineral content in insects and the potential of its change due to processing. 展开更多
关键词 Edible insects MINERALS NUTRITION Food safety SUSTAINABILITY
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31 Plant Species against Blood Feeding and Disease Vectors Insects: Beyond Anti-Insect Properties, Unvalued Opportunities and Challenges for Health and Sustainability
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作者 Prudence Bararunyeretse Jean Claude Niyokwizera +1 位作者 Esperance Gateretse Mathias Hitimana 《Pharmacology & Pharmacy》 2024年第5期167-206,共40页
Plants with bioactive properties are greatly useful in preventing and controlling blood-sucking and disease-vector invertebrates, particularly in developing countries and low-income communities. Their application is a... Plants with bioactive properties are greatly useful in preventing and controlling blood-sucking and disease-vector invertebrates, particularly in developing countries and low-income communities. Their application is a promising alternative to synthetic compounds whose use remains a health, environmental, and economic challenge. However, many are still unknown and unvalued, while others are becoming ignored and threatened. The main objective of this ethnobotanical study is to identify and characterize indigenous and locally grown plants against blood-sucking and disease-vector insects. Salient opportunities and challenges of using these plants are documented and discussed. Semi-structured interviews, using a prepared questionnaire, were conducted with 228 informants. The consensus index (CI) was calculated to analyze the reliability of the collected information. The identified 31 anti-insect plant species belong to 20 botanical families, four morphological categories, and six habitat types. They can be categorized as insecticidal plants (42% of the total), insect repellent (42% of the total), and both insecticidal and insect repellent (16% of the total). More than 54% of these are still abundant in the study area, while about 35.5% have become rare and difficultly accessible. Based on the numerical importance of related anti-insect plant species, the seven targeted blood-sucking insects range in the following decreasing order: Jiggers (16 species) > Fire Ants (9 species) > Flies (8 plants) > Mosquitoes (4 species) > Fleas (2 species) > Bedbugs (1 species) > lice (0 species). The three most commonly used plants, with the highest confirmation indices, are Tetradenia riparia (ICs = 0.712), Eucalyptus globulus subsp. maidenii (ICs = 0.302), and Solanum aculeastrum (ICs = 0.288). The antimicrobial role of many locally grown anti-insect plants and the multiple other associated valorization possibilities are ignored by most informants. Domesticating, propagating, protecting, and promoting the sustainable use of these plants would be an appropriate route for their conservation and continued availability. 展开更多
关键词 Blood-Feeding insects Anti-insect Plants BIOPESTICIDES SUSTAINABILITY Burundi
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Analysis of Economic Benefits Brought by Industrialization of Natural Enemy Insects
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作者 Jie XIE Shoumei WAN +5 位作者 Jinyu ZHAO Lingling XIAO Haiyan WANG Jian TANG Xiaolei JI Jing PENG 《Asian Agricultural Research》 2024年第9期11-15,共5页
In the field of biological control of agricultural and forestry pests,natural enemy insects play an important role,constituting the core of modern integrated pest management(IPM)strategy,providing solid support for th... In the field of biological control of agricultural and forestry pests,natural enemy insects play an important role,constituting the core of modern integrated pest management(IPM)strategy,providing solid support for the zero growth goal of chemical pesticide use,and helping the sustainable development of green agriculture.The rise of the natural enemy insect industry has become a key driver of the transformation of green agriculture,injecting vitality into the sustainability and ecological protection of agriculture.With the increasing concern about food safety,environmental protection and ecological balance all over the world,the application scope of natural enemy insects as biological control means is constantly expanding.Its unique ecological adaptability and environmentally friendly characteristics help to reduce dependence on chemical pesticides,ensure the safety of agricultural products and maintain ecological diversity.The purpose of this study is to analyze the current situation of natural enemy insect industry,evaluate its cost and benefit,emphasize its great significance in promoting the transformation of green agriculture,improving production efficiency and promoting ecological protection by drawing lessons from foreign successful experiences,and explore an efficient and sustainable new agricultural development model. 展开更多
关键词 Natural enemy insects INDUSTRIALIZATION Transformation of green agriculture Economic benefits
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Efficacy of Beneficial Fungi Isolates in Solanum lycopersicum L. Protection against Lepidopteran Insects through a Leaf Inoculation Technique
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作者 Joelle Toffa Elie Ayitondji Dannon +4 位作者 Yeyinou Laura Estelle Loko Hervé Bokossa Josky Adikpeto Appolinaire Adandonon Manuele Tamò 《Advances in Microbiology》 CAS 2023年第2期89-105,共17页
Helicoverpa armigera is a key insect pest of tomatoes reducing drastically yields. The effect of the endophytic colonization of tomato plants by Beauveria bassiana using leaf spray as an inoculation method on damage a... Helicoverpa armigera is a key insect pest of tomatoes reducing drastically yields. The effect of the endophytic colonization of tomato plants by Beauveria bassiana using leaf spray as an inoculation method on damage and survival of H. armigera was assessed in a screen house. Two B. bassiana isolates (Bb 115 and Bb 11) and two tomato varieties (a local variety Tounvi and an improved variety Padma) were included in the study. The adaxial and abaxial leaf surfaces were sprayed at a concentration of 10<sup>7</sup> conidia/ml and 10<sup>9</sup> conidia/ml for each isolate and each of the two tomato varieties. Thirty days after inoculation, five discs of tomato leaf and tomato root were cut for each isolate, each concentration per isolate and for each variety. The samples were incubated at room temperature (28°C ± 2°C) and periodically checked for fungal growth. Larval survival was checked and a damage assessment was done on tomato flowers and the leaves. The results show that the lowest Mean Survival Times (MSTs) were recorded on larvae feeding on plants inoculated with Bb 11 (4.2 ± 0.8 days against 11.5 ± 0.2 days for control). Compared to the other treatments, low damage rates of the flowers of the improved variety inoculated with Bb 11 at 10<sup>9</sup> conidia/ml were recorded from the 6th Day After Inoculation (DAI). This rate remains low until the end of treatment. Overall flower damage was lower than leaf damage. The results showed large differences in pathogenicity, with most endophytic isolate belonging to Bb 11 when inoculated at 10<sup>9</sup> conidia/ml using the leaf spraying technique. Data were discussed with regard to the use of endophytism B. bassiana in an integrated tomato pest control approach. 展开更多
关键词 Tomato insect Beauveria bassiana Foliar Spray ENDOPHYTIC Pest Management
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Historical and current climates affect the spatial distribution of herbivorous tree insects in China
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作者 Feixue Zhang Chunjing Wang Jizhong Wan 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第5期1307-1321,共15页
Historical and current climate impacts reshape the evolutionary trajectory and ecological dynamics of entire vegetative communities,which can drive insect species distribution.Understanding the spatial distribution of... Historical and current climate impacts reshape the evolutionary trajectory and ecological dynamics of entire vegetative communities,which can drive insect species distribution.Understanding the spatial distribution of insects can enhance forest management effectiveness.The effects of historical and current climates in the spatial distribution of herbivorous tree insects in China were explored.A species distribution model simulated insect spatial distribution based on 596 species and the distribution probability and richness of these species were assessed in forest ecoregions.The explanatory power of the historical climate was stronger than that of the current climate,particularly historical annual precipitation and annual mean temperatures,for the distribution of herbivorous insects.Under both historical and current climatic conditions,herbivorous tree insects were and are mainly distributed in the North China Plain and the middle and lower reaches of the Yangtze River Plain,namely in the Huang He Plain mixed forests,Changjiang Plain evergreen forests,and Sichuan Basin evergreen broadleaf forests.The Yunnan-Guizhou Plateau and northeast China are regions with large impact differences between historical and current climates.The findings of this study provide valuable insights into herbivorous insect responses to sustained climate change and may contribute to long-term biodiversity conservation activities. 展开更多
关键词 Bioclimatie variables ECOREGIONS Last glacial maximum Spatial distribution Species distribution model Herbivorous tree insects
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Enhancing forest insect outbreak detection by integrating tree-ring and climate variables
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作者 Yao Jiang Zhou Wang +3 位作者 Zhongrui Zhang Xiaogang Ding Shaowei Jiang Jianguo Huang 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第6期279-293,共15页
Annual tree rings are widely recognized as valuable tools for quantifying and reconstructing historical forest disturbances.However,the influence of climate can complicate the detection of disturbance signals,leading ... Annual tree rings are widely recognized as valuable tools for quantifying and reconstructing historical forest disturbances.However,the influence of climate can complicate the detection of disturbance signals,leading to limited accuracy in existing methods.In this study,we propose a random under-sampling boosting(RUB)classifier that integrates both tree-ring and climate variables to enhance the detection of forest insect outbreaks.The study focused on 32 sites in Alberta,Canada,which documented insect outbreaks from 1939 to 2010.Through thorough feature engineering,model development,and tenfold cross-validation,multiple machine learning(ML)models were constructed.These models used ring width indices(RWIs)and climate variables within an 11-year window as input features,with outbreak and non-outbreak occurrences as the corresponding output variables.Our results reveal that the RUB model consistently demonstrated superior overall performance and stability,with an accuracy of 88.1%,which surpassed that of the other ML models.In addition,the relative importance of the feature variables followed the order RWIs>mean maximum temperature(Tmax)from May to July>mean total precipita-tion(Pmean)in July>mean minimum temperature(Tmin)in October.More importantly,the dfoliatR(an R package for detecting insect defoliation)and curve intervention detec-tion methods were inferior to the RUB model.Our findings underscore that integrating tree-ring width and climate vari-ables as predictors in machine learning offers a promising avenue for enhancing the accuracy of detecting forest insect outbreaks. 展开更多
关键词 Forest disturbance insect outbreaks Machine learning Tree-ring analysis
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Twenty-Three Years of Insect Pollinator-Dependent Crop Studies in Agro-Ecological Zones of Cameroon (2011-2020)
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作者 Népidé Ndobadé Carine Egono Ndemé Carole Christèle +1 位作者 Daniel Farda Mazi Sanda 《Agricultural Sciences》 2024年第8期877-908,共32页
Cultivation of pollinator-dependent crops has expanded globally, increasing our reliance on insect pollination. This essential ecosystem service is provided by a wide range of managed and wild pollinators whose abunda... Cultivation of pollinator-dependent crops has expanded globally, increasing our reliance on insect pollination. This essential ecosystem service is provided by a wide range of managed and wild pollinators whose abundance and diversity are thought to be in decline, threatening sustainable food production. In Cameroon, several studies on pollinator-dependent crops carried out in different agro-ecological zones (AEZ) have been published in national and international journals, in order to present the importance and impact of flowering insects on fruit and seed yields of plant species. We proposed to produce a review article highlighting the different flowering insects and their importance for different plants according to AEZ, without however focusing on the quality of the journal (predator or non-predator) and how the different insects were identified (scientific names given in the publications). Thus, from 1997 to 2020, we collected 116 published papers from which only 26 were kept for this review. The results show that Hymenoptera, including the Apidae, followed by Megachilidae, are the most excellent pollinators of plant species in Cameroon, and they are present in different agro-ecological zones. The majority of publications focused on bees, particularly the honeybee Apis mellifera. 展开更多
关键词 Agro-Ecological Zones Cameroon Flowering insects HYMENOPTERA POLLINATORS
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A Review on Characteristics, Extraction Methods and Applications of Renewable Insect Protein
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作者 Adelya Khayrova Sergey Lopatin Valery Varlamov 《Journal of Renewable Materials》 EI CAS 2024年第5期923-950,共28页
Due to the expected rise in the world population,an increase in the requirements for quality and safety of food and feed is expected,which leads to the growing demand for new sources of sustainable and renewable prote... Due to the expected rise in the world population,an increase in the requirements for quality and safety of food and feed is expected,which leads to the growing demand for new sources of sustainable and renewable protein.Insect protein is gaining importance as a renewable material for several reasons,reflecting its potential contribu-tions to sustainability,resource efficiency,and environmental conservation.Some insect species are known to be able to efficiently convert organic waste into high-value products such as protein,requiring less land and water compared to traditional livestock.In addition,insect farming produces fewer greenhouse gas emissions,contri-buting to mitigating climate change.Insects are considered as a major potential alternative to animal or plant protein due to their many nutritional benefits,including high protein,mineral,and vitamin contents.On average,the protein content of insects ranges between 35%and 60%dry weight,which exceeds plant protein sources,such as cereal,soybeans,and lentils.As the acceptance of insect protein grows and technologies advance,the food and feed industries continue to explore and expand their applications,offering consumers diverse and sustainable pro-tein choices.In this review,we discuss the recentfindings relating to insect protein focusing on its characteristics,extraction methods,applications,and opportunities along with some trade-offs and uncertainties. 展开更多
关键词 Circular economy waste utilisation PROTEIN insect Hermetia illucens
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Social Cost Analysis of Biological Control Technology for Crop Diseases and Insect Pests
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作者 Jie XIE Lingling XIAO +4 位作者 Jinyu ZHAO Shoumei WAN Jian TANG Xiaolei JI Jing PENG 《Asian Agricultural Research》 2024年第8期14-16,共3页
With the rapid development of modern agriculture,the prevention and control of crop diseases and insect pests has become an important part to ensure the safety of agricultural production,the quality of agricultural pr... With the rapid development of modern agriculture,the prevention and control of crop diseases and insect pests has become an important part to ensure the safety of agricultural production,the quality of agricultural products and the safety of agricultural ecological environment.Although the effect of traditional chemical prevention and control technology is remarkable,the health risks and environmental problems brought by it should not be ignored.As a green and environmentally friendly means of prevention and control,biological prevention and control technology has gradually become a hot research topic and a trend of agricultural production.This paper is intended to comprehensively evaluate the social costs of biological control technologies for crop diseases and pests,including the health risks reduced,environmental improvements,economic benefits,and barriers to promotion,and put forward corresponding policy recommendations. 展开更多
关键词 CROPS DISEASES and insect PESTS BIOLOGICAL control SOCIAL cost
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Study on Pollinating Insects of Astragalus membranaceus (Ficsh) Bunge 被引量:4
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作者 张建 杨发君 +2 位作者 刘顺 郭爽 任跃英 《Agricultural Science & Technology》 CAS 2010年第2期27-30,共4页
[Objective The aim was to study species and pollinating characters of Astragalus membranaceus(Ficsh)Bunge pollinating insects and lay a theory foundation for the breeding of Astragalus membranaceus(Ficsh)Bunge.[Method... [Objective The aim was to study species and pollinating characters of Astragalus membranaceus(Ficsh)Bunge pollinating insects and lay a theory foundation for the breeding of Astragalus membranaceus(Ficsh)Bunge.[Method] With Astragalus membranaceus(Ficsh)Bunge as research object,the species of pollinating insect and pollination behavior were investigated.[Result] There were 16 pollinating insect species,among which,Bombus ignitus,Bombus lucoru,Apis sp.,Betasyrphus serarius(wiedemann)and Colias erate(Esper)we... 展开更多
关键词 Astragalus membranaceus(Ficsh)Bunge Pollinating insects Flower-visiting behavior Flower-visiting frequency
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Application of Self-propelled Boom Sprayers for Control of Rice Insects and Diseases 被引量:1
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作者 龚艳 于林惠 +3 位作者 张晓 王果 陈伟 陈晓 《Agricultural Science & Technology》 CAS 2016年第7期1667-1670,共4页
Comparisons were performed between self-propelled boom sprayer and traditional mechanis, such as knapsack sprayer and sprayer-duster, stretcher-type powered sprayer, as well as single rotor unmanned sprayer and multi-... Comparisons were performed between self-propelled boom sprayer and traditional mechanis, such as knapsack sprayer and sprayer-duster, stretcher-type powered sprayer, as well as single rotor unmanned sprayer and multi-rotor un- manned sprayer. The effects on rice injury, lodging, and rehabilitation were conclud- ed and drug uniform distribution, sedimentation and prevention effects were ana- lyzed. The results showed that the self-propelled boom sprayer is characterized by high degree of automation, convenient operation, high adaptability, and high work efficiency. What's more, the sprayed fog quality is better, and fog distribution is more uniform. During the work process, fog loss would be diminished substantially, improving work efficiency and cutting down drug and water. It is notable that the underpart of the sprayer can be widely applied to plant protection in large-scale ar- eas in Jiangsu Province, significantly advancing whole-process mechanization of rice production. 展开更多
关键词 RICE SELF-PROPELLED SPRAYERS insect and disease control Deposition distribution
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Species and Diversity Analysis of Flower-visiting Insects of Asian Sacred Lotus in Jiangxi, Hunan and Hubei Provinces 被引量:3
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作者 张旭凤 邵有全 《Agricultural Science & Technology》 CAS 2014年第2期269-274,共6页
[Objective]This study aimed to investigate the community structure, species and quantities of flower-visiting insects of seed lotus in main producing ar-eas of Jiangxi, Hunan and Hubei provinces. [Method] Using sample... [Objective]This study aimed to investigate the community structure, species and quantities of flower-visiting insects of seed lotus in main producing ar-eas of Jiangxi, Hunan and Hubei provinces. [Method] Using sample area survey and netting method in the fixed points to investigate species and quantities of Asian sacred lotus, the species diversity of different locations was evaluated by diversity indices (H′), evenness indices (J) and dominant concentration indices (C). [Result] Apis mel ifera, Apis cerana cerana, Xylocopa (Koptortosoma) sinensis, Xylocopa (s.str.) valga and Xylocopa (Al oxylocopa) appendiculata, al of which belong to order Hy-menoptera were the main pol inators of lotus. Temperature was the main factor which influenced the foraging behaviors of flower-visiting insects. The daily activities of X. (s.str.) valga and X. (Al oxylocopa) appendiculata were bimodal, and that of A. mel-lifera, A. cerana cerana and X. (s.str.) valga were unimodal. The percentage of wild pol inators in Linxiang of Hunan Province and Xianning of Hubei Province were only 20.59% and 3.90% respectively, and there were six species of flower-visiting insects in Linxiang and three in Xianning. The percentages of wild pol inators in Shicheng of Jiangxi Province and the lotus garden in Huazhong Agricultural University were 55.61% and 90.40% respectively, and the flower-visiting insects belonged to 13 and 12 species respectively. The diversity index (H′) and evenness index (J) were listed here in a decreasing order: Shicheng of Jiangxi &gt;lotus garden in Huazhong Agricul-tural University&gt;Linxiang of Hunan &gt;Xianning of Hubei. The sequence of dominant concentration indices (C) was Shicheng of Jiangxi &lt;the lotus garden in Huazhong Agricultural University&lt;Linxiang of Hunan&lt;Xianning of Hubei. The diversity indices (H′), evenness indices (J) and dominant concentration indices (C) of each sample location were consistent. [Conclusion] The species and quantities of Asian sacred lotus vary in different ecological areas. The species and quantities of Linxiang in Hunan Province and Xianning in Hubei Province are rare. The increase of lotus production must depend on bee pol ination. 展开更多
关键词 Nelumbo nucifera Flower-visiting insect Daily activity Community di-versity Bee pollination
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Feature Extraction of Stored-grain Insects Based on Ant Colony Optimization and Support Vector Machine Algorithm 被引量:1
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作者 胡玉霞 张红涛 +1 位作者 罗康 张恒源 《Agricultural Science & Technology》 CAS 2012年第2期457-459,共3页
[Objective] The aim was to study the feature extraction of stored-grain insects based on ant colony optimization and support vector machine algorithm, and to explore the feasibility of the feature extraction of stored... [Objective] The aim was to study the feature extraction of stored-grain insects based on ant colony optimization and support vector machine algorithm, and to explore the feasibility of the feature extraction of stored-grain insects. [Method] Through the analysis of feature extraction in the image recognition of the stored-grain insects, the recognition accuracy of the cross-validation training model in support vector machine (SVM) algorithm was taken as an important factor of the evaluation principle of feature extraction of stored-grain insects. The ant colony optimization (ACO) algorithm was applied to the automatic feature extraction of stored-grain insects. [Result] The algorithm extracted the optimal feature subspace of seven features from the 17 morphological features, including area and perimeter. The ninety image samples of the stored-grain insects were automatically recognized by the optimized SVM classifier, and the recognition accuracy was over 95%. [Conclusion] The experiment shows that the application of ant colony optimization to the feature extraction of grain insects is practical and feasible. 展开更多
关键词 Stored-grain insects Ant colony optimization algorithm Support vector machine Feature extraction RECOGNITION
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Description of Natural Enemies of Pasture Pest-Carabdae Insects
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作者 赵同贵 吴彤林 +1 位作者 莫熙礼 邓伟 《Plant Diseases and Pests》 CAS 2010年第2期41-44,共4页
The investigation result of grassland predators Carabidae in southwest of Guizhou was reported. Taxonomic status, morphological characteristics of 5 genera and 13 species of insect predators were described, their livi... The investigation result of grassland predators Carabidae in southwest of Guizhou was reported. Taxonomic status, morphological characteristics of 5 genera and 13 species of insect predators were described, their living habits and incidence were outlined. 展开更多
关键词 Southwest of Guizhou Morphological characteristic insect Description of species
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Study on Species and Behaviors of Flowervisiting Insects on Mussaenda pubescens
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作者 何应森 徐晓燕 李昕然 《Agricultural Science & Technology》 CAS 2016年第5期1200-1203,共4页
[Objective] This study aimed to understand the species and behaviors of flower-visiting insects on Mussaenda pubescens Ait.f.in the Mount Emei National Nature Reserve.[Method] The species,visiting frequency,visiting t... [Objective] This study aimed to understand the species and behaviors of flower-visiting insects on Mussaenda pubescens Ait.f.in the Mount Emei National Nature Reserve.[Method] The species,visiting frequency,visiting time and behaviors of flower-visiting insects on M.pubescens were studied by collection,identification and image capture.[Result] The flower-visiting insects on M.pubescens in the Mount Emei covered total 26 species with 21 species from Lepidoptera,2 species from Hymenoptera,and 3 species from Diptera.Thus,Lepidoptera were the main group of pollinators for c in the Mount Emei National Nature Reserve.The daily activity rhythms of Lepidoptera,Hymenoptera and Diptera showed different characteristics,and they were characterized by single-peak type and double-peak type.[Conclusion] This study will provide certain theoretical basis for studies on the diversity of flower-visiting insects on plants in the Mount Emei National Nature Reserve. 展开更多
关键词 M.pubescens Flower-visiting insects Flowering-visiting behavior Mount Emei
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Research Progress on the Development and Utilization of Proteins in Edible Insects
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作者 冉文波 赵晨霞 《Agricultural Science & Technology》 CAS 2014年第4期683-687,共5页
The recent progress on the proteins in edible insects was summarized, in- cluding the nutritional value, healthy value, food safety, extraction and content mea- surement of the proteins in edible insects, as well as t... The recent progress on the proteins in edible insects was summarized, in- cluding the nutritional value, healthy value, food safety, extraction and content mea- surement of the proteins in edible insects, as well as the main development direc- tion of edible insect proteins. And we also pointed out the bottlenecks that restricted the development and utilization of proteins in edible insects, and proposed the prospect of the research, development and utilization of edible insects proteins. 展开更多
关键词 Edible insects PROTEIN Research progress Development and utilization
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Dynamic flight stability of hovering insects 被引量:29
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作者 Mao Sun Jikang Wang Yan Xiong 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第3期231-246,共16页
The equations of motion of an insect with flapping wings are derived and then simplified to that of a flying body using the "rigid body" assumption. On the basis of the simplified equations of motion, the longitudin... The equations of motion of an insect with flapping wings are derived and then simplified to that of a flying body using the "rigid body" assumption. On the basis of the simplified equations of motion, the longitudinal dynamic flight stability of four insects (hoverfly, cranefly, dronefly and hawkmoth) in hovering flight is studied (the mass of the insects ranging from 11 to 1,648 mg and wingbeat frequency from 26 to 157Hz). The method of computational fluid dynamics is used to compute the aerodynamic derivatives and the techniques of eigenvalue and eigenvector analysis are used to solve the equations of motion. The validity of the "rigid body" assumption is tested and how differences in size and wing kinematics influence the applicability of the "rigid body" assumption is investigated. The primary findings are: (1) For insects considered in the present study and those with relatively high wingbeat frequency (hoverfly, drone fly and bumblebee), the "rigid body" assumption is reasonable, and for those with relatively low wingbeat frequency (cranefly and howkmoth), the applicability of the "rigid body" assumption is questionable. (2) The same three natural modes of motion as those reported recently for a bumblebee are identified, i.e., one unstable oscillatory mode, one stable fast subsidence mode and one stable slow subsidence mode. (3) Approximate analytical expressions of the eigenvalues, which give physical insight into the genesis of the natural modes of motion, are derived. The expressions identify the speed derivative Mu (pitching moment produced by unit horizontal speed) as the primary source of the unstable oscillatory mode and the stable fast subsidence mode and Zw (vertical force produced by unit vertical speed) as the primary source of the stable slow subsidence mode. 展开更多
关键词 insect Dynamic stability Equations of motion Navier-Stokes simulation Natural modes of motion
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An Insect Imaging System to Automate Rice Light-Trap Pest Identification 被引量:23
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作者 YAO Qing LV Jun +4 位作者 LIU Qing-jie DIAO Guang-qiang YANG Bao-jun CHEN Hong-ming TANGJian 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第6期978-985,共8页
Identification and counting of rice light-trap pests are important to monitor rice pest population dynamics and make pest forecast. Identification and counting of rice light-trap pests manually is time-consuming, and ... Identification and counting of rice light-trap pests are important to monitor rice pest population dynamics and make pest forecast. Identification and counting of rice light-trap pests manually is time-consuming, and leads to fatigue and an increase in the error rate. A rice light-trap insect imaging system is developed to automate rice pest identification. This system can capture the top and bottom images of each insect by two cameras to obtain more image features. A method is proposed for removing the background by color difference of two images with pests and non-pests. 156 features including color, shape and texture features of each pest are extracted into an support vector machine (SVM) classifier with radial basis kernel function. The seven-fold cross-validation is used to improve the accurate rate of pest identification. Four species of Lepidoptera rice pests are tested and achieved 97.5% average accurate rate. 展开更多
关键词 automatic identification imaging system rice light-trap pests SVM cross-validate
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THE ECO-GEOGRAPHICAL DISTRIBUTION OF FOREST INSECTS IN CHINA 被引量:2
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作者 Fang SanyangNortheast Forestry University 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1992年第2期13-22,共10页
The ceo-geographical division of forest insects in China is generally divided into 4 levels: region, subrcgion, area and province. The region is formed by isolation of ocean, high mountain and desert etc. The division... The ceo-geographical division of forest insects in China is generally divided into 4 levels: region, subrcgion, area and province. The region is formed by isolation of ocean, high mountain and desert etc. The division of subrcgion is on the basis of resistance of extreme temperature humidity in winter. The division of area or province is on the basis of landform, type of vegetation in forest zone and temperature zone. 展开更多
关键词 Eco-geographical distribution Forest insect.
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Dynamic flight stability of hovering model insects:theory versus simulation using equations of motion coupled with Navier-Stokes equations 被引量:9
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作者 Yan-Lai Zhang Mao Sun 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第4期509-520,共12页
In the present paper, the longitudinal dynamic flight stability properties of two model insects are predicted by an approximate theory and computed by numerical sim- ulation. The theory is based on the averaged model ... In the present paper, the longitudinal dynamic flight stability properties of two model insects are predicted by an approximate theory and computed by numerical sim- ulation. The theory is based on the averaged model (which assumes that the frequency of wingbeat is sufficiently higher than that of the body motion, so that the flapping wings' degrees of freedom relative to the body can be dropped and the wings can be replaced by wingbeat-cycle-average forces and moments); the simulation solves the complete equations of motion coupled with the Navier-Stokes equations. Comparison between the theory and the simulation provides a test to the validity of the assumptions in the theory. One of the insects is a model dronefly which has relatively high wingbeat frequency (164 Hz) and the other is a model hawkmoth which has relatively low wingbeat frequency (26 Hz). The results show that the averaged model is valid for the hawkmoth as well as for the dronefly. Since the wingbeat frequency of the hawkmoth is relatively low (the characteristic times of the natural modes of motion of the body divided by wingbeat period are relatively large) compared with many other insects, that the theory based on the averaged model is valid for the hawkmoth means that it could be valid for many insects. 展开更多
关键词 insect Hovering Dynamic flight stability Averaged model Equations-of-motion Navier-Stokes simulation
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