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61.
Serotonin, or 5-hydroxytryptamine (5-HT), plays critical roles as a neurotransmitter and neuromodulator that control or modulate many behaviors in insects, such as feeding. Neurons immunoreactive (IR) to 5-HT were detected in the central nervous system (CNS) of the larval and adult stages of the stable fly, Stomoxys calcitrans, using an immunohistological technique. The location and pattern of the 5-HT IR neurons are described and compared for these two different developmental stages. Anatomical features of the fly feeding system were analyzed in third instar larvae and adult flies using a combination of histological and immunohistological techniques. In third instar larvae, the cibarial dilator muscles were observed within the cibarial pump skeleton and innervated by 5-HT IR neurons in nerves arising from the brain. There were four pairs of nerves arising from the frontal surface of the larval brain that innervate the cibarial pump muscles, pharynx, and muscles controlling the mouth hooks. A strong serotoninergic innervation of the anterior stomatogastric system was observed, which suggests 5-HT may play a role in the coordination of different phases of food ingestion by larvae. Similarly, many 5-HT IR neurons were found in both the brain and the thoracico-abdominal ganglia in the adult, some of which innervate the cibarial pump dilator muscles and the stomatogastric muscles. This is tnhe first report describing neuromuscular structures of the stable fly feeding system. The results reported here suggest 5-HT may play a critical role in feeding behaviors of stable fly larvae and adults.  相似文献   
62.
城市供水系统摇蚊污染发生与防治研究   总被引:8,自引:1,他引:8  
近年来 ,国内已有 1 0余个省区城市供水系统中先后发生了摇蚊幼虫 (红虫 )污染事件。文章介绍了国内外供水系统摇蚊发生概况 ;分析了供水系统中摇蚊发生的 3个主要原因 :原水环境污染 ,水处理过程摇蚊污染和二次供水污染。简要回顾了国外供水系统摇蚊污染防除的历史和进展 ;重点介绍了目前国内供水行业所采用物理、化学以及生物的方法在水厂净水处理及二次供水过程防除摇蚊污染的研究 ;同时指出了当前有关研究和实践中存在的主要问题是对摇蚊生物学和生态学等知识的缺乏。对该问题开展进一步研究提出了建议  相似文献   
63.
Damage caused by insect herbivores, notably Asian rice gall midge, Orseolia oryzae is more prevalent in the rice-growing belts of India's southern and north-eastern states. As a prelude to resistant cultivar development, the identification of genomic regions for resistance in the source population is crucial. In the present investigation, 202 rice genotypes were phenotyped and assayed with genomic markers reported for gall midge resistance. Positive skewness and platykurtic distribution of response scores suggested the inheritance of gall midge resistance in the study population. The marker gm3del3 contributed the most genetic variation, followed by RM28574 and marker RM22709 explained minimal variation. A marker-trait association analysis with a single marker-trait linear regression approach was performed to discover gall midge resistant genomic region/genes. The marker RM17480 on chromosome 4 reported to be linked with gm3 gene was found significantly associated with the gall midge resistance genomic region with allelic effects in a negative direction favouring resistance reaction. The allelic effects of significantly associated markers were correlated significantly with the phenotypic variation of gall midge damage scores. Genes identified in the vicinity of this marker contribute to stress response reactions in rice plants. The 200 bp allele of the marker was associated with susceptibility, while the 250 bp allele was associated with resistance expression. This allelic association with trait variation suggests the importance of associated marker for utilisation in marker-assisted selection programmes to incorporate resistance alleles into elite rice genotypes.  相似文献   
64.
65.
水稻对稻瘿蚊为害补偿力与经济阈值研究   总被引:4,自引:0,他引:4  
1994-1998年针对水地稻瘿蚊为害补偿力及经济阈值进行了研究,结果表明:⑴水稻对稻瘿蚊为害具有较强的补偿能力,但基本属于不足补偿,不同标葱梯度其补偿力不同,每造成1%的标葱引起的产量损失远小于1%,其补偿率一般在55%-80%之间,产量损失及其损失率与标葱数呈极显正相关,有效穗和产量补偿率与标葱数则呈显负相关;⑵在相同受害程度下,密植损失大,补偿力小,而稀植损失小,补偿能力大,秧苗期补偿效  相似文献   
66.
The development of self-biting behavior in captive monkeys is little understood and poses a serious risk to their well-being. Although early rearing conditions may influence the expression of this behavior, not all animals reared under similar conditions self-bite. The purpose of this study was to examine the effects of three rearing conditions on biting behavior and to determine whether early infant behavior can predict later self-biting. The subjects were 370 rhesus macaques born at the National Institutes of Health (NIH) Animal Center between 1994 and 2004. They were reared under three conditions: mother-reared in social groups (n=183), peer-reared in groups of four (n=84), and surrogate-peer-reared (n=103). Significantly more surrogate-peer-reared animals self-bit compared to peer-only or mother-reared animals. There was no sex difference in self-biting, but this result may have been affected by a sex bias in the number of observations. The durations of behaviors exhibited by the surrogate-peer-reared subjects were recorded in 5-min sessions twice a week from 2 to 6 months of age while the animals were in their home cages and play groups. In the play-group situation, surrogate-peer-reared subjects who later self-bit were found to be less social and exhibited less social clinging than those that did not self-bite. Home-cage behavior did not predict later self-biting, but it did change with increasing age: surrogate clinging and self-mouthing decreased, while environmental exploration increased. Our findings suggest that surrogate rearing in combination with lower levels of social contact during play may be risk factors for the later development of self-biting behavior.  相似文献   
67.
In nature, Anopheles gambiae mosquitoes are found at various energy levels and such females must choose between seeking somatic energy from sugar sources and obtaining both somatic and gametic energy from blood hosts. We used a straight-tube olfactometer containing a simulated unobtainable blood host (human foot smell protected by a net) as well as a sugar source (honey odor). We assessed female probing rate and residence time at the net as a function of energy state (0, 24, 48, 72-h starved). In our trials, 0-h starved females showed low response to human odor, low probing rate, and residence time at the human odor site. By contrast, both 48 and 72-h individuals showed high response to foot odor, longer residence time, and higher probing rates. Seventy-two-h females also flew towards the honey source less often than other groups. Our findings suggest that managing sugar sources might be a viable strategy for influencing mosquito biting behavior.  相似文献   
68.
Galls on Bauhinia cupulata (Fabaceae) were investigated in two physiognomies of the Cerrado, riparian and dry forest, in the municipality of Barreiras (Western Bahia, Brazil) from October 2012 to July 2014. Four insect gall morphotypes were found. They were characterized based on shape, color, indumentum, plant organ of occurrence and galling taxon. A new galling species, Schizomyia barreirensis, is described, illustrated (larva, pupa, male, female and gall) and compared to other Neotropical congeneric species.  相似文献   
69.
Morphological, molecular and ecological studies revealed that Kiefferia Mik, 1985 (Diptera: Cecidomyiidae) is not a monotypic genus. Two new species, Kiefferia ezoensis sp. nov. and K. olla sp. nov. from Japan and Korea are added to the known European species, Kiefferia pericarpiicola. The new and known species are distinguishable from each other mainly by the shape of the larval sternal spatula. Molecular data support the results of morphological classification. Species of Kiefferia induce fruit galls on various plant species of Apiaceae. We found that K. ezoensis and K. olla utilized exclusively Angelica ursina and Oenanthe javanica, respectively. In contrast, we listed 37 apiaceous species belonging to 23 genera as hosts for K. pericarpiicola from previously published reports, suggesting the existence of additional undescribed species. Life history patterns of the three species are distinctly different from each other. Mature larvae of K. ezoensis and K. olla drop to the ground with the fruit gall in October and September, respectively, whereas mature larvae of K. pericarpiicola quit the galls and drop to the ground in August. A key to the Kiefferia species is provided based on morphological features and information on life history patterns and host ranges.  相似文献   
70.
Four isolates of the entomopathogenic fungus Metarhizium anisopliae were tested for their potential to control the biting midge Culicoides brevitarsis, the principal vector of bluetongue virus in Australia. Adult C. brevitarsis died three to eight days after walking on paper substrate treated with 0.7 g/m2 conidia of any of the isolates, indicating that M. anisopliae has potential as a surface treatment or topical application control strategy. Incorporation of the fungus into freshly excreted cattle dung at rates of between 0.25 and 1 g conidia/kg reduced the emergence of adult midges by up to 98.5% compared to untreated dung indicating that M. anisopliae has the potential to control C. brevitarsis larvae in cattle dung. Three of the isolates produced similar mortality rates on adult and immature C. brevitarsis while the fourth isolate produced lower, but still significant, mortality rates on adult and immature stages.  相似文献   
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