我国麻类资源的多样性及其保护利用对策

在“七五”、“八五”、“九五”研究的基础上,本文论述了我国麻类资源的种类、数量与分布以及保护利用现状等方面的问题,并提出了多样性的可持续发展和利用对策,为今后我国麻类资源的收集、保存、鉴定、创新和利用提供依据。     

我国麻类作物种质资源保护与利用研究进展

总结了我国麻类种质资源在收集保存、繁殖更新、鉴定评价和分发利用等方面的最新进展.10年来,新增麻类种质697份,保存资源数量增至9764份,居世界第1位;繁殖更新麻类资源5343份次,基本解决了麻类资源安全保存和供种等问题;完成农艺性状、经济性状及特性鉴定6543份次,筛选出麻类优异种质296份;向全国50家单位分发种质4296份次,资源利用效率大幅提高.并针对当前存在的问题,提出了下一步工作的明确目标和任务.     

甘肃药用植物资源多样性及其保护利用

甘肃省药用植物资源丰富,藻菌地衣、苔藓、蕨类、裸于和被子植物共1计1300余种。其中包括传统中药、藏药、维药、蒙药及民间草药,含多种植物区系成分,在遗传基因、物种与生态系统三个层次上表现出了丰富的多样性。由于生态环境的破坏和药材不合理采挖,又使其多样性受到严重威胁。为保护甘肃药用植物资源的多样性,在西部大开发中充分发挥其资源优势,建议尽快建立资源信息库,出版有关植物志,加强应用基础研究,解决生产中的实际问题,发挥甘肃地方特色,开发民族药优质产品,以期产生良好的社会效益、经济效益和生态效益。     

生物多样性资源：利用、保护与管理

生物多样性在本质上是一种具有多重价值,高度综合的资源形式,是人类社会生存与发展的物质基础,在人类社会发展过程中,生物多样性资源利用与保护之间日益表现为彼此冲突的特征,但并非不可调和。本文认为,协调二者关系,实现生物多样性资源可持续利用和区域社会经济可持续发展的根本途径是生物多样性资源管理,它由主体层,客体层和目标层构成,应该具备主体多元化,参与的广泛性,过程的动态性与持续性,尺度性与地域性和公平性等基本特征,主体层是由以人为核心的各种组织形式构成的,是从社会经济系统中分化出来的一个职能层次;客体层也就是管理的对象层,是生物多样性资源系统和社会经济系统的耦合体,目标层包括生物多样性资源的可持续利用,生态文明的构建与发展和区域社会经济的可持续发展,生态文明是生物多样性资源可持续利用和区域社会可持续发展的根本保障,其中,主体层和客体层构成了生物多样性资源管理的实体部分,而目标层则是生物多样性资源管理的参照体系,生物多样性资源管理包括管理范围界定,问题辨识,目标确定,政策制定与方案运筹,实施,监测与评价,适应性调整6个基本步骤,是一个复杂的多层次动态反馈过程,这一过程中,科学研究发挥着非常重要的作用,因此应该在加强生物多样性科学研究的同时融合科学与管理的关系,使科学成果真正转化成效的管理行为。     

盐城滩涂生物多样性保护及其可持续利用

论述了盐城滩涂的自然概况和动植物资源,分析了生物多样性保护和利用过程中取得的成绩和存在的不足,针对所存在的问题提出了盐城滩涂生物多样性保护及其可持续利用的对策,包括深入开展生物多样性资源的调查和研究,注重滩涂湿地生态环境的保护和改造,加强自然保护区的建设和管理,以科技进步促进生物多样性的保护和利用,围绕资源保护和持续利用实施滩涂开发。     

西藏类乌齐县野生藏药植物资源多样性及其保护利用

为摸清类乌齐县野生藏药植物资源,为野生藏药植物资源的保护、开发利用和系统研究提供科学依据.本研究根据类乌齐县植被情况,结合藏医院藏药专家野外采集经验,采用样线调查法,记录出现的野生植物信息,并采集当地常用藏药植物标本.结果表明:类乌齐县共有野生植物56科170属332种,单种及寡种科属比例较高,总体分化趋势较弱;生活型...     

论我国昆虫多样性的保护与利用

本文论述了保护昆虫多样性的意义、我国昆虫多样性的基本特点及面临的问题、昆虫多样性的保护战略和利用对策。文中强调指出,昆虫是生物界的一个主要类群,在我国,需要防治的害虫大约只占全部昆虫种类数的1%,其余种类对人类都是有益或者是中性的,它们不仅可以作为显花植物的传粉者、为人类提供食物和各种工业原料,而且可以作为许多害虫或杂草的天敌,以及用于环境净化和科学研究。我国由于地域辽阔,生境复杂,因此,昆虫种类极为丰富,珍稀物种及有益昆虫较多。然而,由于受到人类活动的干扰,我国昆虫多样性面临着生境遭到破坏,物种濒于灭绝,天敌大量减少等问题。为了有效地保护和利用我国的昆虫资源,作者提出了一些战略和对策。     

扬子鳄种群的微卫星DNA多态及其遗传多样性保护对策分析

扬子鳄(Alligator sinensis)是中国特有的珍稀保护动物,为保护这一濒危物种,我国于80年代初在安徽宣州先后建立了扬子鳄繁殖研究中心和国家级扬子鳄自然保护区,现饲养种群存鳄数量已达10000余头。为了揭示扬子鳄种群的遗传结构,共采集了39个个体的样品,其中包括6件剥制标本,按代系不同,分为野生群、F1代饲养群及F1代饲养群,用微卫星DNA分子标记对其进行研究。分析结果显示：扬子鳄种群在微卫星水平表现出很低的遗传多样性,平均等位基因数A=2．38,平均有效等位基因数Ne=1．60,平均观察杂合度He=0．374,平均期望杂合度He=0．350,平均多态信息含量PIG=0．327,3个群体间A、Ne、Ho、He、PIC及各微卫星位点等位基因频率分布无显著差异,但F1代饲养群在Ami-μ-6和Ami-μ-222两个位点表现出极显著的遗传不平衡。扬子鳄种群遗传多样性水平低下的主要原因是近几十年来种群数量大幅减少造成,现阶段应将全部现存的扬子鳄作为一个整体加以保护。     

夏腊梅的遗传多样性及其保护

夏腊梅（Sinocalycanthus chinensis)是国家二级保护的珍稀濒危植物,夏腊梅属（Sinocalycanthus)的唯一代表,仅间断分布于我国浙江省临安市天台县极狭小的范围内,本文采用等位酶淀粉凝胶电泳技术对采自上述两地的天然居群和天目山自然保护区引种的人工居群的553个样品进行了遗传多样性检测,并与浙江腊梅（Chimonan-thus zhejiangensis)作对比,检测结果表明夏腊梅的遗传多样性极低,从14个酶系统检测到的23个位点看,在物种水平上每位点的等位基因平均数（A）为1.2,多态位点（P）占21.7%,观察杂合度（Ho)为0.010。在居群水平上,A=1.0-1.1,P=0-13.0%,Ho=0-0.014。而对照种浙江腊梅杭州植物园人工居群的上述指标分别为A=1.5,P=39.1%,Ho=0.071。夏腊梅的2个自然居群之间在Mdh-4,Pgd-3和Sod-1发生显著的分化,但居群内亚居群间几乎没有分化,在天目山自然保护区引种的人工居群中没有检测到多态性,说明作为迁地保护的天目山自然保护区人工居群并没能有效地保护夏腊梅的遗传多样性,由于目前自然保护区基本上采用不加人为干预的经营方式,划人龙塘山自然保护区内的自然亚居群会因为森林的自然演替而灭绝,所以,自然保护区目前的这种经营方式不适合对夏腊梅的保护,夏腊梅的例子说明,当我们对保护对象的生物学特性缺乏认识时,我们既不知道应该保护什么,也不知道应该如何保护。     

中国淡水藻类生物多样性研究进展

概述了中国淡水灌类物种多样性和遗传多样性研究的现状,讨论了生境的多样性和及其与藻类物种多样性的关系。同时探讨了藻类多样性所面临的问题,提出了关于保护和利用措施方面的建议。     

贵州稻种资源遗传多样性研究现状与展望

贵州稻种资源遗传多样性的研究与利用已取得较大进展.主要表现在(1)收集整理了地方稻种5168份并入国家种质库长期保存,系统完成其农艺性状和特性的鉴定与评价,筛选出一批矮秆、大穗、大粒、优质、特种稻、抗病虫、抗衰以及耐冷、抗旱性突出的优异种质;(2)研究表明,品种多样性是环境对品种的选择和品种对环境的适应双向作用的环境同化产物,在贵州高原低温高湿寡照生境下形成禾类和旱稻等种质资源;(3)开展了地方稻种中细胞质雄性不育恢复源、非sd-1基因新矮源、广亲和、双(多)胚等特性有利基因资源的鉴定和筛选;(4)明确了收集品种的类型及其保存途径,建立以基础样品、活动样品和核心样品的分类数据库为基础的资源信息管理系统.对推动研究工作的深入发展等问题展开了讨论.     

麻类作物组织培养及遗传转化研究进展

概述了国内外红麻等麻类作物快速繁殖、花药培养、原生质体培养、体细胞胚发生、器官发生等几个方面的组织培养以及遗传转化的研究进展,并对存在的问题进行了讨论,提出了进一步研究的一些见解,以期为促进麻类组织培养及遗传转化研究提供科学依据。     

麻类脱胶高效菌株果胶裂解酶基因克隆与表达

【目的】克隆麻类脱胶高效菌株Dickeya sp.DCE-01的果胶裂解酶基因并进行原核表达,对表达产物进行纯化和酶学性质研究。【方法】根据该菌株全基因组序列预测的果胶裂解酶基因Q59419设计引物,PCR扩增后将该基因连接到pEASY-E1和pACYCDuet-1载体上,导入E.coli BL21(DE3)进行表达。选择酶活力高的阳性克隆子进行大量诱导表达后,采用超滤和Sephadex G-100凝胶层析两步法纯化出果胶裂解酶,研究其酶学性质。【结果】克隆到果胶裂解酶基因pel(GenBank登录号:JX964997),其序列全长1 128 bp,编码375个氨基酸。pACYCDuet-1-pel-BL表达胞外果胶裂解酶活力最高,发酵液粗酶活达298.8 IU/mL。其最适反应温度为50°C,最适pH为9.0;保温1 h,酶活稳定温度≤45°C,稳定pH为9.0?10.0。酶催化作用依赖于Ca2+,其最适作用浓度为2 mmol/L;Zn2+、Ca2+和NH4+促进酶活力,Fe3+和Pb2+严重抑制酶活力;聚半乳糖醛酸钠为该酶的最适底物。【结论】从麻类脱胶高效菌株中发掘到碱性果胶裂解酶基因,其表达产物在生物质加工过程中具有重要工业化应用前景。     

Assessment of the genetic diversity and genetic relationships of Lilium in China using ISSR markers

China is a center of natural distribution and diversity of genus Lilium around the world. In the study, the genetic diversity and genetic relationships of Lilium in China were analyzed by inter-simple sequence Repeat (ISSR) markers. The 6 highly polymorphic ISSR primers were selected to amplify the 20 Lilium species. The results showed that a total of 114 DNA bands were amplified, all of which were polymorphic loci (P = 100%), the effective number of alleles (Ne) was 1.2753, and the difference value between observed number of alleles (Na) and effective number of alleles (Ne) was 0.7247, and the Nei's genetic diversity (H) was 0.2048, and the Shannon's information index (I) was 0.3503. These results indicated that there is significant genetic difference among Lilium species in China. Taking the average genetic similarity coefficient (Gs) 0.5313 as the threshold, the 20 tested Lilium species were clustered into 5 groups, which was not entirely consistent with traditional clustering by morphological traits. The results obtained from this study can provide a reference for the molecular study of Lilium germplasm resources.     

Molecular identification and genetic diversity among six Begomovirus isolates affecting cultivation of cucurbitaceous crops in Uttar Pradesh,India

Begomoviruses cause a number of serious diseases of cultivated crops and are considered as the major constraint for the cultivation of several crops all over the world. During a survey in the years 2007 and 2008, the typical symptoms of Begomovirus (yellow mosaic and yellow vein) were observed on six cucurbitaceous crops, viz. bitter gourd (Momordica charantia L.), pointed gourd (Trichosanthes dioica), pumpkin (Cucurbita pepo), pumpkin (Cucurbita maxima), sponge gourd (Luffa cylindrica) and ridged gourd (Luffa acutangula) being cultivated in northern India. Begomovirus infection was suspected due to significant infestation of whiteflies (Bemisia tabaci, the known vector of Begomoviruses) on these species. The presence of Begomovirus was detected from the total DNA extracted from six infected leaf samples of these species by polymerase chain reaction using the specific primers of a well-characterised Begomovirus. The ～800 bp amplicons of these isolates were cloned, sequenced and the data obtained were compared with each other and with sequence database available in GenBank for best sequence identities and phylogenetic relationships. Based on highest 97–99% sequence identities and closest phylogenetic relationships, four representative Begomovirus species were identified as Ageratum enation virus (from T. dioica), Squash leaf curl China virus (from C. maxima), Tomato leaf curl New Delhi virus (from M. charantia, L. cylindrica and L. acutangula) and Tomato leaf curl Palampur virus (from C. pepo). These results suggested the existence of a high genetic diversity among Begomoviruses infecting cucurbitaceous crops.     

Lignification in the flax stem: evidence for an unusual lignin in bast fibers

In the context of our research on cell wall formation and maturation in flax (Linum usitatissimum L) bast fibers, we (1) confirmed the presence of lignin in bast fibers and (2) quantified and characterized the chemical nature of this lignin at two developmental stages. Histochemical methods (Weisner and Maüle reagents and KMnO₄-staining) indicating the presence of lignin in bast fibers at the light and electron microscope levels were confirmed by chemical analyses (acetyl bromide). In general, the lignin content in flax bast fibers varied between 1.5% and 4.2% of the dry cell wall residues (CWRs) as compared to values varying between 23.7% and 31.4% in flax xylem tissues. Immunological and chemical analyses (thioacidolysis and nitrobenzene oxidation) indicated that both flax xylem- and bast fiber-lignins were rich in guaiacyl (G) units with S/G values inferior to 0.5. In bast fibers, the highly sensitive immunological probes allowed the detection of condensed guaiacyl-type (G) lignins in the middle lamella, cell wall junctions, and in the S1 layer of the secondary wall. In addition, lower quantities of mixed guaiacyl–syringyl (GS) lignins could be detected throughout the secondary cell wall. Chemical analyses suggested that flax bast-fiber lignin is more condensed than the corresponding xylem lignin. In addition, H units represented up to 25% of the monomers released from bast-fiber lignin as opposed to a value of 1% for the corresponding xylem tissue. Such an observation indicates that the structure of flax bast-fiber lignin is significantly different from that of the more typical woody plant lignin, thereby suggesting that flax bast fibers represent an interesting system for studying an unusual lignification process.     

园艺作物核心种质构建的研究进展

构建核心种质是植物遗传资源的研究热点和重点之一,对种质资源的鉴定、保存、利用与交流具有重要意义。本文简要介绍了植物遗传资源核心种质的概念及其构建方法,综述了园艺作物核心种质构建的研究新进展,并对今后该领域的研究趋势进行了展望。提出了种质分组及取样策略是园艺作物核心种质构建方法研究的重点;应及时构建一批大宗园艺作物以及我国原产和特产园艺作物的核心种质;高度重视基于重测序技术快速、精准、高通量地挖掘园艺作物核心种质优异基因的研究以及要加强科研管理与协作,切实提高我国园艺作物核心种质研究成果的共享性等观点,为园艺作物种质资源的深入研究与高效利用提供理论依据和技术参考。     

Assessment of genetic diversity and population structure of swamp eel Monopterus albus in China

Swamp eel has become one of the most economically important fish in China. However, the wild swamp eel is facing the serious challenge of declining population and germplasm degeneration because most of farming swamp eel fingerlings was collected by fishing wild individuals. In this study, the genetic variation of Monopterus albus in six dominant farming regions was investigated based on the mitochondrial DNA D-Loop of 1008 bp in length. 180 individuals from 6 populations were examined and 74 haplotypes were observed. The overall genetic diversity was abundant and which its SD population was highest but CQ population was lowest. There was obvious genetic differentiation among investigated populations. Phylogenetic analysis revealed that these individuals were divided into four distinct genetic clades, clade A, B, C, and D. Clade A should be the most common ancestor clade. AH and CQ populations might originate from one single ancestor in maternal clade A. Clade C should be a native important clade in China. Though the genetic diversity did not suffered obvious decreasing, it is still imperative to take effective conservation measurements and establish an efficient selective breeding program.