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41.
【目的】本研究旨在明确外源保幼激素(juvenile hormone, JH)对异色瓢虫Harmonia axyridis成虫卵巢发育以及生殖信号通路中关键基因转录水平的影响。【方法】以萝卜蚜Lipaphis erysimi饲喂的异色瓢虫雌成虫为空白对照组,以点滴同体积丙酮的雌成虫为溶剂对照组,对人工饲料饲喂的羽化后第2天的雌成虫点滴不同剂量(80, 120和160 ng/头)JHⅢ 1, 3, 5, 7和9 d后,解剖成虫卵巢,拍照并测量卵巢长度及其第一卵室的长度和宽度。利用qPCR分析在最适JHⅢ剂量(120 ng/头)处理后1, 5和9 d的异色瓢虫雌成虫生殖信号通路中关键基因JH受体methoprene-tolerant (Met)基因、krüppel homolog 1(Kr-h1)基因、卵黄原蛋白(vitellogenin, Vg)基因(Vg1和Vg2)和卵黄原蛋白受体(vitellogeninreceptor, VgR)基因表达水平。【结果】与溶剂对照组相比,点滴80和120 ng/头剂量JHⅢ可促进异色瓢虫成虫卵巢发育,其中120 ng/头剂量JHⅢ处理羽化后第2天雌成虫后7 d卵巢中出现大量卵黄沉积,与萝卜蚜饲喂的空白对照组卵巢发育状态一致,卵巢长度以及第一卵室的长度和宽度均显著高于溶剂对照组的;160 ng/头剂量JHⅢ处理则抑制卵巢发育。qPCR结果表明,120 ng/头剂量JHⅢ处理后5和9 d雌成虫中HaMet, HaKr-h1, HaVg1, HaVg2和HaVgR基因表达量较对照组(丙酮处理组)均增加,其中处理后5 dHaMet, HaVg1和HaVgR基因表达量分别为对照组的2.78, 13.14和8.28倍,处理后9 d分别为对照组的2.36,1.85和2.01倍,差异极显著。【结论】120 ng/头JHⅢ可促进异色瓢虫成虫卵巢发育,上调处理后5和9 d时雌成虫HaMet, HaKr-h1, HaVg和HaVgR基因表达量;推测这些关键基因在保幼激素调控异色瓢虫卵巢发育及卵黄形成过程发挥重要作用。 相似文献
42.
基于约束的基因组尺度代谢网络模型(genome-scale metabolic models,GEMs)分析已被广泛应用于代谢表型的预测。而实际细胞中代谢速率除计量学约束外,还受到酶资源可用性和反应热力学可行性等其他因素影响,在GEMs中整合酶资源约束或者热力学约束构建多约束代谢网络模型可以进一步缩小优化解空间,提升细胞表型预测的准确性。文中主要对近年来多约束模型的研究进展进行了综述,介绍了不同多约束模型的构建方法,以及其在研究基因敲除影响、预测可行途径和提供代谢瓶颈信息等方面的应用。将多种约束条件进一步与代谢模型整合,可更准确地预测细胞代谢的瓶颈和关键调控改造靶点,从而为工业菌种代谢工程改造提供精确的设计指导。 相似文献
43.
44.
山西省重点保护野生植物资源及区系特征研究 总被引:3,自引:0,他引:3
张殷波;张晓龙;卢怡萌;李明 《植物研究》2013,33(1):18-23
以《国家重点保护野生植物名录(第一批)》和《山西省重点保护野生植物名录(第一批)》为依据,建立山西省重点保护野生植物名录。共记录57种保护植物,隶属于38科45属(其中国家Ⅰ级保护2种,国家Ⅱ级保护6种,省级保护49种)。分析结果得出,山西省重点保护野生植物在全省的分布不集中,零散分布于全省61个县区境内,且绝大多数物种的分布范围很狭窄。山西省重点保护野生植物区系具有复杂多样、起源古老、孑遗植物和单种属多等特点,科、属植物区系成分以温带分布型占优势,同时也有较明显的热带性质,过渡性特征比较明显,有其独特的地理优势和保护价值。本研究旨在对山西省重点保护野生植物资源现状及区系特征进行初步研究,从而为野生植物资源的保护和合理有效地利用提供科学的理论依据与参考。 相似文献
45.
Abstract. 1. Population budgets for Rhynchaenus fagi, based for the most part on samples of beech leaves taken in June, were constructed for a 10-year period (Northern Ireland) and a 3-year period (Scottish borders).
2. There were years of sustained population growth and sustained decline, but not enough evidence to suggest a cycle. Similar population levels were found at both sites in all but one year.
3. Key factors were associated with the adult stage, although egg mortality may also make a significant contribution to population change.
4. Unknown sources of mortality embodied in the residual mortality were also suspected of acting in a density dependent manner, compensating for variation in parasitism.
5. Death rate of larvae within mines was related to May temperature in Northern Ireland, but not so clearly in Scotland. 相似文献
2. There were years of sustained population growth and sustained decline, but not enough evidence to suggest a cycle. Similar population levels were found at both sites in all but one year.
3. Key factors were associated with the adult stage, although egg mortality may also make a significant contribution to population change.
4. Unknown sources of mortality embodied in the residual mortality were also suspected of acting in a density dependent manner, compensating for variation in parasitism.
5. Death rate of larvae within mines was related to May temperature in Northern Ireland, but not so clearly in Scotland. 相似文献
46.
T. M. Brooks A. Cuttelod D. P. Faith J. Garcia-Moreno P. Langhammer S. Pérez-Espona 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2015,370(1662)
‘Key biodiversity areas'' are defined as sites contributing significantly to the global persistence of biodiversity. The identification of these sites builds from existing approaches based on measures of species and ecosystem diversity and process. Here, we therefore build from the work of Sgró et al. (2011 Evol. Appl.
4, 326–337. (doi:10.1111/j.1752-4571.2010.00157.x)) to extend a framework for how components of genetic diversity might be considered in the identification of key biodiversity areas. We make three recommendations to inform the ongoing process of consolidating a key biodiversity areas standard: (i) thresholds for the threatened species criterion currently consider a site''s share of a threatened species'' population; expand these to include the proportion of the species'' genetic diversity unique to a site; (ii) expand criterion for ‘threatened species'' to consider ‘threatened taxa’ and (iii) expand the centre of endemism criterion to identify as key biodiversity areas those sites holding a threshold proportion of the compositional or phylogenetic diversity of species (within a taxonomic group) whose restricted ranges collectively define a centre of endemism. We also recommend consideration of occurrence of EDGE species (i.e. threatened phylogenetic diversity) in key biodiversity areas to prioritize species-specific conservation actions among sites. 相似文献
47.
48.
Two new species of oribatid mites of the genus Scapheremaeus (Oribatida, Cymbaeremaeidae), Scapheremaeus
gibbus
sp. n. and Scapheremaeus
luxtoni
sp. n., are described from New Zealand. Scapheremaeus
gibbus
sp. n. is morphologically most similar to Scapheremaeus
humeratus Balogh & Mahunka, 1967, but differs from the latter by the number of notogastral, genital and adanal setae, morphology of bothridial setae, position of adanal lyrifissures and absence of humeral processes. Scapheremaeus
luxtoni
sp. n. is morphologically most similar to Scapheremaeus
yamashitai Aoki, 1970, but differs from the latter by the morphology of notogastral and rostral setae, morphology of leg solenidia φ2 and development of humeral processes. The species Scapheremaeus
zephyrus Colloff, 2010 is recorded for the first time in New Zealand. An identification key to the known New Zealand species of Scapheremaeus is provided. 相似文献
49.
Old World species of the genus Seticornuta Morley are reviewed. Seven species of this genus were recorded worldwide, but only one species, Seticornuta
albopilosa (Cameron), was known from the Old World. Here, we report one new species, Seticornuta
koreana
sp. n., from South Korea, and redescribe the other known Old World species, Seticornuta
albopilosa, with photographs. 相似文献
50.
A new species of Cumacea belonging to the genus Lamprops Sars was collected from the East Sea of Korea. This new species resembles Lamprops
comatus Zimmer, Lamprops
carinatus Hart, Lamprops
flavus Harada, Lamprops
pumilio Zimmer, Lamprops
tomalesi Gladfelter, and Lamprops
obfuscatus (Gladfelter) in lacking lateral oblique ridges on the carapace and lateral setae on the telson. The new species, however, is distinguished from its congeners by having a dorsal concave groove and a lateral rounded depressed area on pereonite 2. The new species is fully illustrated and compared with related species. A key to the world Lamprops species lacking lateral ridges on the carapace is also provided. 相似文献