中国农作物及其野生近缘植物多样性研究进展

本研究围绕粮食、经济、果树、蔬菜、饲草与绿肥、花卉六大类作物，以物种多样性和遗传多样性等为主线，开展了中国农作物及其野生近缘植物多样性研究，取得重大进展。科学界定和系统规范了种质资源概念和范畴，提出了层次结构的理论，查清了中国粮食与农业植物有9631个物种及其分布、特征特性及用途；深入研究了中国农作物种质资源的本底，首次明确了中国农作物总计有528种（类），涉及1339个栽培物种和1930个野生近缘植物物种；优化了农作物种以下农艺性状分类技术指标，阐明了中国农作物地方品种的987个变种、978个变型、1223个农艺性状特异类型的植物学特征、生物学特性及其遗传多样性；得出了中国是禾谷类作物裸粒基因、糯性基因、矮秆基因和育性基因等特异基因的起源中心或重要起源地之一的结论；首次编撰出版了《中国作物及其野生近缘植物》专著6卷，并编撰了《中国粮食与农业植物物种名录》，形成了具有中国特色的作物种质资源学科理论体系。为农作物种质资源的高效利用、保障粮食安全和农业可持续发展奠定了基础。     

作物野生近缘种的研究与保护需要重视

<正>作物野生近缘种(crop wild relatives,CWR)是宝贵的植物遗传资源,对于改良作物品种,提高粮食和其他栽培植物的产量和质量具有十分重要的意义。这是因为野生种的遗传多样性十分丰富,而现代栽培品种的遗传多样性却非常贫乏。在生物技术快速发展的今天,野生植物,特别是作物野生近缘种的利用前景更加广阔。     

云南及周边地区野菜和野果资源

本文是根据“云南及周边地区生物资源调查”项目的系统调查结果汇总的。云南及周边地区野菜和野果资源,指的是该地区栽培蔬菜、果树及其野生近缘植物之外的可食的野菜和野果。云南及周边地区是多个少数民族聚居区,各少数民族都有采食野菜和野果的习俗,并且在长期采食野菜和野果中,积累了丰富的食用方法。本文介绍云南及周边地区的野菜和野果,旨在为深入研究和开发利用这些资源,并为国家制定野生植物保护有关政策提供基础数据和信息。     

《中国作物及其野生近缘植物——菌类作物卷》

正《中国作物及其野生近缘植物》是一部详细介绍了中国作物及其野生近缘植物多样性的专著,由中国农业出版社出版发行。该书设有编辑委员会及总编辑,各卷均另设主编,由全国百余位专家学者执笔,历经多年努力,数易其稿完成。该书对每种作物的起源、演化和分类进行了详细的叙述,并详细介绍了各个作物的野生近缘植物,以供育种科研人员根据各种作物的不同情况选育遗传基础更加广阔的品种。     

广西农作物种质资源遗传多样性

广西与云贵高原相连 ,具有多样化的地形和亚热带气候 ,农作物类型丰富。本文回顾近 5 0年来广西农作物种质资源研究的进展和现状 ,从作物的种类、分类学、评价鉴定利用情况 ,以及同工酶分析等基础研究 ,与中国起源有关的作物野生近缘种反映广西农作物种质资源的遗传多样性 ,2 0世纪 80年代以来 ,广西农作物资源的多样性迅速减少 ,本文对原地保存农作物种质资源的多样性提出商榷意见     

作物野生近缘种的保护与利用

作物野生近缘种将是保证下一世纪粮食充足的重要因素。近30余年来国际国内非常重视作物野生种质资源的搜集、保存、鉴定、评价和利用的研究。我国作物野生近缘种特别丰富,同时受威胁非常严重。因此,加大力度开展作物及其野生近线种种质资源的遗传多样性、保存技术、种质创新和利用的研究是刻不容缓的。     

西部大开发必须抢救作物种质资源

我国西部作物种质资源十分丰富,尤以野生近缘种为最。3种野生稻大部分分布在西部。小麦野生近缘植物中,69％的物种只生于西部。野生大豆的多样性中心在西部——黄河中游。西部还有茶、柑橘、桃、李、梅、杏、山楂、樱桃、海棠、猕猴桃等多种干鲜果树和瓜菜的野生种。我国西部堪称农作物野生近缘植物的宝库。西部作物名特优品种和独特类型很多,如新疆的吐鲁番葡萄、哈密甜瓜、库尔勒香梨,宁夏的中宁枸杞,甘肃兰州的白兰瓜、百合等。过去考察中发现西藏有很多千年以上的古桑、光核桃子等。川西、陕南等地有稀有、珍贵的果、菜品种。我国在作物种质资源保护方面虽然做了大量工作,但是野生种损失严重,特别是分布较广的野生稻和野生大豆,多处分布点已大为缩小或绝迹。西部大开发中,生态环境不可避免地将发生变化。为了使种质资源不再继续损失,建议做好以下几件事：(1)在西部地区再进行一次作物野生近缘植物的考察收集;(2)通过调查,科学地建立野生近缘植物的保护区(点);(3)抢救栽培种的名特优种质资源,为发展特有产业储备物质基础;(4)保护好已收集的种质资源,勿使得而复失。     

作物野生近缘种的原生境保护

作物野生近缘种是作物种质创新和品种改良的天然基因库,全球30%的作物增产得益于野生近缘种在作物育种中的利用。然而,由于生境破坏和污染、资源过度利用、盲目引种和气候变化等导致大量自然群体消失和群体遗传多样性丧失,对作物野生近缘种的繁衍和进化形成了严重威胁。原生境保护是在自然条件下对作物野生近缘种及其生态环境进行保护,维持其进化潜力,保护物种与环境互作的进化过程,是保护作物野生近缘种的重要途径之一。本文在分析国内外原生境保护政策和技术手段的基础上总结了作物野生近缘种原生境保护技术路线,综述了国内外对作物野生近缘种的原生境保护进展,并基于中国国情提出了作物野生近缘种存在的问题,探讨了未来作物野生近缘种原生境保护和野生近缘种可持续利用的发展方向和工作重点,强调把基因组、表型组和环境因子相关大数据与作物野生近缘种保护、研究和利用紧密结合,为作物野生近缘种的有效保护和高效利用提供强有力的理论和信息支撑。     

作物野生近缘植物保护与可持续利用

作物与人类文明的传承和发扬密不可分。世界人口和人均需求量的持续增加导致植物资源的供需失衡。作物自身相对较低的遗传多样性是影响产量和品质的主要因素。作物野生近缘植物在生境中积累了多种基因型，并在应对环境变化时形成了多种表现型，是作物种质保护和品种改良的重要遗传资源。但随着生境破坏以及全球气候变化等不确定因素的持续影响，使得作物野生近缘植物的存活和繁殖质量受到了严重威胁，必须采取有效的措施进行保护。本文总结了国内外对作物野生近缘植物保护工作所取得的进展，应对我国在保护中存在的问题提出相应的改良建议。最后以国内代表性作物为例，对其保护与利用情况进行了讨论。     

贵州少数民族地区作物稀有种质资源和野生近缘植物

"贵州农业生物资源调查"项目于2012-2014年已对贵州省21个县(市)进行了系统调查。系统调查的21个县(市)均有少数民族集居,各民族有不同的传统文化和生活习俗,在世代相传中赋予了当地作物种质资源丰富的民族文化内涵。并且,当地的地形地貌复杂,气候类型多样。正因为这种多样的自然条件和各异的民族文化,造就了这里丰富的作物稀有种质资源和野生近缘植物。本次调查获得的作物稀有种质资源和野生近缘植物,对作物的分类研究和新品种选育以及商业开发,将会有一定的利用价值。     

A Unique Protease Cleavage Site Predicted in the Spike Protein of the Novel Pneumonia Coronavirus (2019-nCoV) Potentially Related to Viral Transmissibility

正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases     

Curcuminoids as inhibitors of thioredoxin reductase: A receptor based pharmacophore study with distance mapping of the active site

Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.     

Comparative morphology of the carpel in the Liliaceae: Hewardieae, Petrosavieae, and Tricyrteae

The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.     

Enterovirus 71 3C proteolytically processes the histone H3 N-terminal tail during infection

Highlights
1. The N-terminal tail of histone H3 is specifically cleaved during EV71 infection.
2. Viral protease 3C is identified as a protease responsible for proteolytically processing the N-terminal H3 tail.
3. Our finding reveals a new epigenetic regulatory mechanism for Enterovirus 71 in virus-host interactions.     

Detection of EBV and HHV6 in the Brain Tissue of Patients with Rasmussen’s Encephalitis

Rasmussen’s encephalitis (RE) is a rare pediatric neurological disorder, and the exact etiology is not clear. Viral infection may be involved in the pathogenesis of RE, but conflicting results have reported. In this study, we evaluated the expression of both Epstein-Barr virus (EBV) and human herpes virus (HHV) 6 antigens in brain sections from 30 patients with RE and 16 control individuals by immunohistochemistry. In the RE group, EBV and HHV6 antigens were detected in 56.7% (17/30) and 50% (15/30) of individuals, respectively. In contrast, no detectable EBV and HHV6 antigen expression was found in brain tissues of the control group. The co-expression of EBV and HHV6 was detected in 20.0% (6/30) of individuals. In particular, a 4-year-old boy had a typical clinical course, including a medical history of viral encephalitis, intractable epilepsy, and hemispheric atrophy. The co-expression of EBV and HHV6 was detected in neurons and astrocytes in the brain tissue, accompanied by a high frequency of CD8⁺ T cells. Our results suggest that EBV and HHV6 infection and the activation of CD8⁺ T cells are involved in the pathogenesis of RE.     

Perinatal Vertical Transmission of Chikungunya Virus in Ruili,a Town on the Border between China and Myanmar

正Dear Editor,Chikungunya virus (CHIKV), an arbovirus in the family of Togaviridae, genus Alphavirus, is transmitted by the A.aegyptii or A. albopictus mosquito, and causes disease in humans characterized by fever, rash, and arthralgia (Silva and Dermody 2017; Suhrbier 2019). It was first reported in 1953 in Tanzania, and caused only a few outbreaks and sporadic cases in Africa and Asia in last century. However, in the epidemic in 2004, CHIKV acquired mutations that conferred enhanced transmission by the A. albopictus mosquito(Schuffenecker et al. 2006). Since then, it has successively caused outbreaks in Africa, the Indian Ocean, South East Asia, the South America, and Europe (Zeller et al. 2016).