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The aim of this study was to investigate the secretion of brain‐derived neurotrophic factor (BDNF)‐like neuropeptide in the silkworm, Bombyx mori , by using immunocytochemical techniques on the brain and retrocerebral complex of fifth instar larvae. In the brain, four pairs of median neurosecretory cell (MNC) bodies and six pairs of lateral neurosecretory cell (LNC) bodies had distinct immunoreactivities to this peptide, suggesting that this peptide is produced from two types of brain neuron. These reactivities were much stronger in the MNC than in the LNC. Labeled MNC projected their axons into the contralateral corpora allata, to which axons of labeled MNC were eventually innervated, through decussation in the median region, contralateral nerve corporis cardiaci I and nerve corpora allata I. Labeled LNC extended their axons into the ipsilateral corpora allata to be innervated through the ipsilateral nerve corporis cardiaci II and nerve corpora allata I. These results suggest that BDNF is secreted as a neurohormone from MNC and LNC of the brain into the corpora allata.  相似文献   
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Tabanid flies were surveyed using New Jersey light traps and Mosquito Magnet® traps at US Army installations and training sites in the northern part of Gyeonggi Province, Republic of Korea. A total of 344 tabanid flies, comprising 14 species and 5 genera, were collected from June to August during 2003‐2004. Dominant species were Chrysops vanderwulpi (57.3%), Haematopota sinensis (29.1%), Haematopota koryoensis (4.4%) and Tabanus mandarinus (2.3%). Mosquito Magnet traps that generated CO2through the combustion of propane gas were nearly 6 times more effective in collecting tabanid flies than New Jersey light traps. Based on Mosquito Magnet trap collections, peak populations occurred from mid‐June to early July.;  相似文献   
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ABSTRACT Like many other sub-social insects, Copris tripartitus Waterhouse requires parental care during the development period in the brood balls. Mass-rearing is achieved by using indoor rearing systems and adding more dung after taking away the brood balls containing eggs. Without parental care, larvae are often affected by desiccation, as well as by fungal or sciarid fly intrusion of the brood balls. This study developed a good substitute for brood ball rearing medium. A significantly greater number of progeny survived to adulthood from broods produced by beetles reared on vermiculite medium (90.69±10.98%) than on peat moss medium (44.82±13.92%). Results of the study suggest that to protect the brood balls from desiccation and to produce healthy adults, 15-20% moisture content vermiculite must be used as brood ball rearing medium for most species reared in the laboratory.  相似文献   
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A survey was conducted in tomato fields at different localities to assess the distribution of tomato fruitworm Helicoverpa armigera Hübner (Lepidoptera: Noctuidae) in Punjab Province, Pakistan. The effect of weather factors on its population was also investigated. Eleven tomato-growing districts were selected and data for larval population and fruit infestation were recorded. The maximum larval population (5.2 larvae/plant) of H. armigera was recorded in Bahawalpur district with 32.6% fruit infestation. However, the minimum larval population (1.4 larvae/plant) inflicted 14.7% fruit infestation in Rawalpindi district. The temperature was positively correlated while relative humidity showed negative interaction with the larval population and fruit infestation.  相似文献   
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Lispe patellitarsis Becker is identified for the first time in Korea. Diagnoses and illustrations of the habitus and male genitalia are given.  相似文献   
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以呼伦贝尔沙地樟子松地理分布南缘天然林为研究对象,采用Hegyi竞争指数与点格局等分析方法,研究了沙地樟子松天然林的种群结构、种内竞争、空间格局及幼树更新等特征。结果表明:1)所调查区域天然沙地樟子松纯林处于中幼龄阶段,属增长型种群;2)其竞争指数与对象木胸径服从幂函数关系CI=242.24D~(-1.12)(R~2=0.91);3)幼树在小尺度上呈聚集分布,中树与大树在中大尺度上呈随机分布;幼树与中树在小尺度上呈正相关性,中树与大树在小尺度呈负相关性;4)竞争指数与更新幼树和存活更新幼树的密度均呈显著正相关性。在林分管理中需要充分考虑林木竞争、空间格局以及种群更新的关系,本研究可为沙地樟子松天然林的经营管理与保护提供重要的科学依据。  相似文献   
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Orthotylus pallen (Mastumura, 1911) is recorded for the first time from Korea and is diagnosed. An image of its dorsal habitus as well as illustrations of the male and female genitalia are provided. A key to and checklist of Korean Orthotylus species are given.  相似文献   
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