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81.
随着农作物种质资源数量的不断增加,种质资源交流的日益频繁以及种质资源利用的逐步深入,农作物种质资源数据库的建设对农作物的应用研究和基础性研究至关重要。上海市农业生物基因中心借助于本中心保存的近21万份种质资源的信息,开发了一套上海农作物种质资源数据库,本文主要阐述了该数据库设计和构建的目的、原则和数据库的架构、运行环境以及主要功能模块。上海农作物种质资源数据库采用了B/S结构,平台系统利用多层逻辑架构实现了对农作物种质资源数据信息的收集、存储、查询、统计分析等功能。外部用户通过浏览器即可访问平台系统,浏览查询种质资源信息。内部管理员可使用平台的受限功能,需要认证成功后才可使用后台管理功能,实现对整个平台数据的管理。注册用户还可通过基因资源数据库提交引种申请,管理员结合管理信息系统实现对外供种全流程的网络化,借此可提高工作效率,增加工作流程的透明度。  相似文献   
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宋莹  刘娜  杨瑞恒  刘俊杰  张敏 《菌物学报》2020,39(6):1109-1116
香菇是我国深受欢迎的食药用菌,产量居食用菌产业之首。为拓宽栽培香菇菌株的遗传背景,解决现有主栽香菇菌株种性退化的问题,本研究以香菇‘808’菌株与3个香菇野生资源、3个栽培菌株(辽抚4号、BY1和荷香)开展单-双杂交育种,开发适合当地栽培环境的主栽品种。研究结果显示:在270对单-双杂交组合中,通过锁状联合观察和与亲本的拮抗试验,鉴定出89个杂交子,进一步通过栽培试验筛选出10个性状相对优良的候选菌株;最终通过农艺性状对比试验,筛选出ZJXG 5和ZJXG 8两个优良杂交菌株,这两个菌株均以当地长白山野生资源S1和本地主栽菌株BY1为双核杂交亲本选育而来,表现出超亲显著、菇形圆整、颜色呈浅褐色的特性,前4潮生物学效率在86%-88%之间。本研究结果揭示,在香菇杂交育种中,当亲本菌株来源地域与杂交后代菌株筛选地域相近时,单双杂交亲和率、杂交菌株的出菇率和丰产性指标较高,这提示我们,利用当地野生香菇资源更有利于创制适合当地自然环境的地方品种。  相似文献   
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The familial placements of Cyrtandromoea Zoll. and Wightia Wall., two small and enigmatic South‐East Asian genera, have long been controversial in Lamiales. Here we adopt a two‐step approach to resolve their phylogenetic relationships. We initially reconstructed a large‐scale phylogeny of Lamiales using six chloroplast markers (atpB, matK, ndhF, psbBTNH, rbcL, and rps4). The results showed that both Cyrtandromoea and Wightia emerged in the LMPO clade, including Lamiaceae, Mazaceae, Phrymaceae, Paulowniaceae, and Orobanchaceae. Based on the second set of six chloroplast markers (atpB, matK, ndhF, rbcL, rps16, and trnL‐F) and two nuclear ribosomal regions (external transcribed spacer and internal transcribed spacer) for the analyses focusing on the LMPO clade, our results revealed that Cyrtandromoea was consistently nested within Phrymaceae, whereas Wightia was supported as sister to Phrymaceae by the chloroplast DNA dataset or sister to Paulowniaceae by the nuclear ribosomal DNA dataset. Morphological and anatomical evidence fully supports the inclusion of Cyrtandromoea in Phrymaceae, and an updated tribal classification is done for Phrymaceae with five tribes, that is, Cyrtandromoeeae Bo Li, Bing Liu, Su Liu & Y. H. Tan, trib. nov., Diplaceae Bo Li, Bing Liu, Su Liu & Y. H. Tan, trib. nov., Leucocarpeae, Mimuleae, and Phrymeae. The conflicting phylogenetic position of Wightia indicated by different genome markers results in difficulty placing the genus in either Phrymaceae or Paulowniaceae. Considering the distinct morphological differences between Wightia and other families in the LMPO clade, we here propose a new family, Wightiaceae Bo Li, Bing Liu, Su Liu & Y. H. Tan, fam. nov., to accommodate it, which is the 26th family recognized in Lamiales.  相似文献   
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From 50 to 90% of wild plant species worldwide produce seeds that are dormant upon maturity, with specific dormancy traits driven by species' occurrence geography, growth form, and genetic factors. While dormancy is a beneficial adaptation for intact natural systems, it can limit plant recruitment in restoration scenarios because seeds may take several seasons to lose dormancy and consequently show low or erratic germination. During this time, seed predation, weed competition, soil erosion, and seed viability loss can lead to plant re‐establishment failure. Understanding and considering seed dormancy and germination traits in restoration planning are thus critical to ensuring effective seed management and seed use efficiency. There are five known dormancy classes (physiological, physical, combinational, morphological, and morphophysiological), each requiring specific cues to alleviate dormancy and enable germination. The dormancy status of a seed can be determined through a series of simple steps that account for initial seed quality and assess germination across a range of environmental conditions. In this article, we outline the steps of the dormancy classification process and the various corresponding methodologies for ex situ dormancy alleviation. We also highlight the importance of record‐keeping and reporting of seed accession information (e.g. geographic coordinates of the seed collection location, cleaning and quality information, storage conditions, and dormancy testing data) to ensure that these factors are adequately considered in restoration planning.  相似文献   
88.
放线菌是目前细菌域最大的谱系之一,门下物种繁多。放线菌作为人类生产和生活极为密切的微生物类群,其强大的代谢产物编码能力为人们所共识。放线菌系统学是以实现对放线菌进行分类、鉴定、命名为目标的基础学科,因此它是放线菌资源研究和开发利用的重要理论基础。近期,我们放线菌资源与利用团队对2009年版放线菌分类系统再次进行了更新和修订,并被国际权威分类学期刊IJSEM杂志接受发表,进一步巩固了我国在本领域的国际领先地位。重点对放线菌的概念演变、分类地位变迁,以及放线菌系统学研究的最新进展做全面概述,并对其未来发展方向进行了展望,以供国内从事本领域研究的同行参考。  相似文献   
89.
《Médecine Nucléaire》2020,44(4):231-249
The original thyroid scan (TS) was widely used to identify typical imaging patterns, suggesting the widely accepted main following clinical diagnoses: Grave's disease, Toxic adenoma, [hetero]-nodular goiters and thyroiditis. With the diffusion of sensitive TSH assays, considerable advances in the comprehension of the molecular mechanisms of hormonosynthesis, and new quantification possibilities especially using 123I, the TS is a textbook of molecular imaging. The image can be finely quantified with, not only as regards the Uptake (123IUp) and related parameters but also, the quantification of the spatial targeting leading to a Spatial Target Index (STI). Using this new molecular 123I-TS, TSH values, and when required, correlation to Multiparametric Ultrasounds (MPUS), we generated a basic classification system of hyperthyroidism, with well-defined indexed criteria (C11-1 to C17-3), that allows reporting 24 distinct etiologies. Selected criteria involve TS and contrast patterns, precocious 123IUp (p123IUp), maximal TSH-dependent physiological Uptake, lobar concentration, Uptake and concentration ratios, STI, 99mTc-MIBI TS and correlative MPUS. This approach allows to identify 4 subtypes of Graves’ disease, including hyperplastic, nodular and common GD variants entangled with Hashimoto's struma, 4 subtypes of Thyroid Functional Autonomy, including Disseminated Functional Autonomy, that cannot be diagnosed with other conventional procedures. Criteria C14-1 to C17-3 report on hyperthyroidism and iodine overload, factitia, main thyroiditis presentations and rare central or tumoral etiologies of hyperthyroidism. This classification, based on 123I-TS molecular imaging, leads to unprecedented diagnostic finesse and paves the way for a personalized theranostic approach in thyroid pathology. Further development towards artificial intelligence networks is under study.  相似文献   
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