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1.
以“元莜麦”和“555”杂交得到的281个F2单株为作图群体,利用20对AFLP引物、3对SSR引物和1个穗型性状构建了一张大粒裸燕麦遗传连锁图。该图谱全长1544.8cM,包含19个连锁群,其上分布有92个AFLP标记、3个SSR标记和1个穗型形态标记,不同连锁群标记数为2-14个,长度在23.7-276.3cM之间,平均长度为81.3cM,标记间平均距离为20.1cM。穗型标记分离比符合3:1,11个AFLP标记表现为偏分离,偏分离比为11.5%。该图谱符合遗传连锁框架图的要求,为今后大粒裸燕麦的QTL定位、分子标记辅助育种和比较基因组学等研究奠定基础。  相似文献   

2.
1 中国畜禽遗传资源多态性研究现状中国是畜禽遗传资源大国 ,全国共有 598个畜禽品种 ,地方品种占品种总数的 77%。至今对家养畜禽遗传多样性的认识 ,主要还是停留在体型特点和性状描述上。虽然生物技术已有了长足的进展 ,但至今没有对任何一个家养畜禽种——牛、羊、猪、马、鸡和鸭等作过全面、系统的品种间亲缘关系分析 ,也没有对哪一个畜禽种做过系统、全面的起源研究。中国固有的地方畜禽品种具有许多优良的性状 ,如太湖猪和寒羊的多胎性、地方品种优良的肉质、抗逆性、抗病性、小体型、性早熟以及其它许多特异性状。地方品种不仅是发…  相似文献   

3.
香椿起源和分类地位的研究   总被引:6,自引:0,他引:6  
依据植物地理学和被子植物起源的理论,研究香椿起源问题。根据研究,推测香椿起源于印度东北部和缅甸及其邻近地区。同时回顾了香椿分类地位的演变历史,香椿属于楝科香椿属已无疑义。但是,根据香椿等位酶分析证明,香椿品种间确实存在差异,确定香椿存在变种,尚需发现、研究和命名。  相似文献   

4.
中国牡丹的起源,演化与分类   总被引:8,自引:0,他引:8  
牡丹被誉为中国国花。牡丹的野生种仅分布于我国。介绍了牡丹的基本形态,习性和民已鉴定的主要种类。  相似文献   

5.
生物多样性的起源演化及亚洲栽培稻的分类   总被引:13,自引:0,他引:13  
本定义的生物多样性包括基因多样性、物种多样性及生态系统多样性。生命起源后到人类明40亿年的地球发展史可划分为前生命的化学进化、生物学进化和人类化进化与生物学进化并行3个阶段,并着重阐述了生物多样性演化中起关键性作用的蓝菌、维管植物与人类三类生物的重要地位和作用,以及地球上生态系统的4次明显扩展。最后以亚洲栽培稻为例说明其历经万年的起源与演化所形成的遗传多样性与分类。  相似文献   

6.
芸薹属植物起源,演化及分类的分子标记研究进展   总被引:8,自引:0,他引:8  
本文概述了近几年来围绕芸薹屋植物的起源,演化和分类所进行的分子标记方面的研究进展,大量研究结果表明:芸薹属6个种基因组之间存在部分同源性,而且有大量的位点发生了重复,表明其是次生的多倍体种,是从一个染色体数目较少的祖选演化而来,在芸薹属基因组演化过程中发生了大量的染色体变异,如重复,易位,倒位,插入和缺失等。  相似文献   

7.
现代地球上绝大部分的生命都是以单个细胞或多个细胞的形式存在的。生命起源后细胞基本结构的形成和细胞结构在进化过程中的发展都是一些重大的生物进化事件。因此对细胞本身的起源和进化的研究是探索生物进化的重要组成部分。1最原始的细胞细胞是如何产生的呢?要解决这...  相似文献   

8.
杜鹃是人们所熟知的高山花卉,以它丰富的种类、独特的景观、优美的姿态和艳丽的花朵吸引着不少分类学家、生态学家和园艺学家对它们进行了广泛的研究和引种。我们在编写西藏植物志和云南植物志的基础上,试图就该属植物的地理分布及其起源问题进行初步的探讨。  相似文献   

9.
中国鲤亚科鱼类的分类、分布、起源及演化   总被引:9,自引:0,他引:9  
本文报道中国鲤亚科鱼类5属23种,内有1新种——尖鳍鲤Cyprinus acutidorsalis sp.nov.,该种的主要鉴别特征为:(1)背鳍前部呈三角形突出,后缘具一很深的缺刻;(2)腹鳍起点前于背鳍;(3)尾鳍下叶不呈桔红色。中国鲤亚科鱼类区系,远较其他国家丰富,地方种有乌原鲤Procypris merus、岩原鲤P.rabaudt、尖鳍鲤、龙州鲤Cyprinus longzhouensis、短鳍鲤C.micristius,抚仙鲤C.fuxianensis、异龙鲤C.yilongensis、大眼鲤C.megalophthalmus、厚唇鲤C.crassilabris、杞麓鲤C.chilia、春鲤C.longipectoralis、大头鲤C.pellegrini、洱海鲤C.barbatus、云南鲤C.yunnancnsis、大理鲤C.daliensis和翘嘴鲤C.ilishaestomus,共16种。云南高原鲤亚科种类特多,仅见于云南的中国地方种多达12种。在云南各湖泊,鲤属鱼类种的分化十分明显,尤其在洱海,所产6种除杞麓鲤外,均为该湖所特有,同域种如此之多,殊属罕见,大概洱海一带即为鲤亚科鱼类的分布中心。云南高原特有种如此丰富,可能与云南地形地貌几经变迁,并具备着使该亚科鱼类区系得以繁荣和分化的良好生态条件密切有关。本文还对鲤亚科鱼类的起源和演化,进行了初步的讨论。  相似文献   

10.
木兰科(Magnoliaceae)的起源、进化和地理分布   总被引:13,自引:0,他引:13       下载免费PDF全文
木兰科为亚洲-美洲间断分布科,全世界有15属,246种,主要分布于亚洲东南部的热带、亚热带地区,从喜马拉雅至日本,向南达新几内亚及新不列颠;少数种类分布于北美东南部、中美至南美巴西.中国有11属,约99种.木兰科的现代分布中心在东亚-东南亚地区.根据木兰科的化石记录、系统发育和现代分布,推测其起源时间为早白垩纪,甚至更早.起源地可能在中国的西南地区,并由此向外辐射,向东经日本、俄罗斯远东地区经白令陆桥进入北美;向西经西亚、欧洲,通过格陵兰进入北美,然后到达南美;向南经印度支那、马来西亚,直至新几内亚.东亚-北美间断分布的形成是受第四纪冰期的影响;南美的木兰科是从北美迁移而来.  相似文献   

11.
黄杉属植物地理学的研究   总被引:2,自引:1,他引:2       下载免费PDF全文
李楠 《植物研究》1993,13(4):404-411
本文对黄杉属的分类进行了整理, 共2组、6种、1变种:黄杉组, 计5种, 花旗松组, 1种, 1变种。前者为典型的\"东亚——北美间断分布\"类型。后者为北美西部特有分布, 作者在分析和探讨本属地理分布、边缘种替代规律的同时。结合有关细胞学和古植物学资料提出:1.黄杉组是原始类群, 花旗松组系由黄杉组经[12]对染色体发生结构重组而产生的进化类群;2.黄杉属是环太平洋植物系发展起来的属。可能起源于东亚。而北美西部则是本属的发展中心。  相似文献   

12.
在大田条件下,采用随机区组设计,研究不同灌溉定额对春播裸燕麦不同生育时期氮磷钾质量分数以及产量性状的影响。结果表明, 裸燕麦高灌溉定额处理不同生育时期茎、叶和穗中氮磷钾的质量分数显著高于低灌溉定额(P<0.05)。滴灌灌溉定额为180 mm(W4处理)时不同生育时期各器官氮磷钾质量分数最高,其他处理由高到低依次为:W5、CK、W3、W2、W1;滴灌灌溉定额为60 mm(W1处理)不同生育时期各器官氮磷钾质量分数最低。滴灌灌溉定额为180 mm(W4处理)时籽粒产量最高(3 249.7 kg/hm),比传统灌溉(CK处理)籽粒产量提高5.98%,比最低灌溉定额(W1处理)提高31.83%。说明适宜的滴灌灌溉定额一定程度上可以促进裸燕麦不同生育时期茎、叶和穗对氮、磷、钾的吸收,使得各器官养分的积累量增加,促使后期有更多养分向穗部转移,从而有利于燕麦籽粒产量的提高。  相似文献   

13.
裸燕麦胚性愈伤组织培养及悬浮系的建立   总被引:11,自引:1,他引:11       下载免费PDF全文
裸燕麦成熟胚在IN培养基上诱导培养,初始愈伤组织为白色、瘤状、外软内硬、易分化植株的非松脆类型。当在IM~IM4培养基上进行循环式调控培养,经7~8个月,初始愈伤组织转变为浅黄色、小颗粒状、生活力强的松脆型胚性愈伤组织。将胚性愈伤组织置于液体培养基中悬浮培养,得到分散性好、生长快的悬浮细胞系。悬浮系经分化培养获得了再生植株,移栽成活率达95%以上。  相似文献   

14.
    
This paper deals with the taxonomy and geographic distribution of the genus Chrysosplenium L. in China. Based on the characters and evolution of the seed, capsule, disk, ovary and leaf, thespecies of this genus can be grouped into 2 subgenera, 5 sections and 16 series. Thereare 2 subgenera, 5 sections and 11 series in China. They are as follows: I. Subgen. Gamosplenium Maxim. emend. J. T. Pan Leaves alternate. Lectotype: Chrysosplenium carnosum Hook. f. et Thoms. 1. Sect. Alternifolia Franch. emend. J. T. Pan Seeds smooth and glabrous. Type: Chrysosplenium alternifolium L. (1) Ser. Nudicaulia Maxim. emend. J. T. Pan Disk obscure or absent; ovary nearly half-inferior, sometimes mostly inferior; capsule generally subtruncate and emarginate at top and bilobed with equal and horizontally divaricate or suberect lobes; seeds smooth and glabrous. Type: Chrysosplenium nudicaule Maxim. (2) Ser. Alternifolia Maxim. emend. J. T. Pan Disk 8-lobed; ovary nearly half-inferior; capsule generally subtruncate and emarginate at top, and bilobed with equal and horizontally divaricate lobes; seeds smoothand glabrous. Type: Chrysosplenium alternifolia L. 2. Sect. Nephrophylloides Turcz. Seeds minutely papillose or pilose. Type: Chrysosplenium sedakowii Turcz. (1) Ser. Macrophylla Franch. emend. J. T. Pan Disk obscure or absent; ovary nearly half-inferior; capsule nearly truncate and emarginate at top, and bilobed with equal lobes; seeds minutely papillose. Type: Chrysosplenium macrophyllum Oliv. (2) Ser. Ovalifolia Maxim. emend. J. T. Pan Disk generally 8-, rarely 4-, lobed, papillae absent around disk; ovary mostly inferior; capsule subtruncate and emarginate at top; seeds minutely papillose or pilose. Type: Chrysosplenium ovalifolium M. Bieb. ex Bunge (3) Ser. Lanuginosa Hara, emend. J. T. Pan Papillae numerous, brown around reduced disk; ovary mostly inferior; capsule nearly truncate and emarginate at top; seeds minutely papillose. Type: Chrysosplenium lanuginosum Hook. f. et Thoms. II. Subgen. Chrysosplenium Leaves opposite. Type: Chrysosplenium oppositifolium L. 1. Sect. Trichosperma J. T. Pan, sect. nov. Capsule not truncate at top, and bilobed with subequal, suberect or divergent lobes. Type: Chrysosplenium trichospermum Edgew. ex Hook. f. et Thoms. This section is divided into 4 series in the world, with only 1 in China. (1) Ser. Nepalensia Maxim. emend. J. T. Pan Disk obscure or absent; ovary generally mostly inferior; cassule not truncate attop, and bilobed with subequal and suberect or divergent lobes; seeds smooth and glabrous. Type: Chrysosplenium nepalense D. Don 2. Sect. Grayana J. T. Pan, sect. nov. Capsule bilobed with distinctly unequal and ascending lobes. Type: Chrysosplenium grayanum Maxim. This section consists of 4 series in the world, with 3 series in China. (1) Ser. Sinica Maxim. emend. J. T. Pan Disk obscure or absent; ovary nearly half-superior; capsule bilobed with distinctlyunequal and ascending lobes; seeds minutely papillose. Type: Chrysosplenium sinicum Maxim. (2) Ser. Esulcata Franch. emend. J. T. Pan Disk (4)-8-lobed; ovary generally half-inferior; capsule bilobed with unequal andascending lobes; seeds minutely papillose or pilose. Lectotype: Chrysosplenium dubium J. Gayex DC. (3) Ser. pilosa maxim. emend. J. T. Pan Disk obscure or absent; ovary nearly half-inferior; capsule bilobed with distinctlyunequal and ascending lobes; seeds distinctly longitudinally ll-18-costate and minutely papillose or tuberculate on the ridge. Type: Chrysosplenium pilosum Maxim. 3. Sect. Chrysosplenium Capsule nearly truncate and emarginate at top, and bilobed with equal and horizontally divaricate lobes. Type: Chrysosplenium oppositifolium L. (1) Ser. Romosa J. T. Pan, ser. nov. Disk distinctly 8-lobed, papillae sparse, brown around disk; ovary mostly inferior; capsule nearly truncate and emarginate at top, and bilobed with equal and horizontallydivaricate lobes; seeds smooth and glabrous. Type: Chrysosplenium ramosum Maxim. This series is monospecific one, also occurring in China, namely C. ramosum Maxim. (2) Ser. Delavayi Hara Disk distinctly 8-lobed, Papillae sparse, brown around the disk; ovary mostly inferior; capsule nearly truncate and emarginate at top, and bilobed with equal and horizontally divaricate lobes; seeds distinctly longitudinally 10-16-costate and transversely striate on the ridge. Type: Chrysosplenium delavayi Franch. This series can be considered as the most advanced one in the Chrysaspleninm L. So far, the Chrysosplenium L. comprises 64 species in the world, among which 1 species is found in North Africa, 2 in South America, 4 in Europe, 5 in North America, 56in Asia, of which 3 occur in Sikkim, 5 Bhutan, 5 Mongolia, 6 north Burma, 6 Korea, 7north India, 8 Nepal, 12 Japan, 17 U.S.S.R. (of which 3 also in Europe), 34 China (including 22 endemic species and 3 new species). In China, Fujian and Guangdong Provinces and Zhuang Autonomous Region of Guangxi each has only 1 species, Taiwan, Zhejiang, Shanxi and Hebei Provinces and Uygur Autonomous Region of Xinjiang each has 2, Anhui, Jiangxi and Hunan Provinceseach has 3, Qinghai Province 4, Heilongjiang, Liaoning and Guizhou Provinces each has5, Jilin and Hubei Provinces each has 6, Gausu Province 8, Shaanxi Province and Xizang (Tibet) Autonomous Region each has 10, Yunnan Province has 11, Sichuan Province has 14. Thus the distribution centre of this genus should be in the north temperate zoneof Asia, and the region covering Shaanxi Gansu, Sichuan, Yunnan and Xizang may beregarded as an important part of this centre. The 7 species of Ser. Nudicaula Maxim. emend. J. T. Pan can be considered as themost primitive ones in this genus. They are mostly distributed in Shaanxi (Qin Ling),south Gansu, southeast Qinghai, southwest Sichuan and nothwest Yunnan of China. Thisregion may be considered as the centre of the origin (or at least differentiation) of thisgenus. The new species and the new varieties described in this paper are as follows: C. hydrocotylifolium Levl. et Vant. var. emeiense J. T. Pan, C. taibaishanense J. T. Pan, C.lixianense Jien ex J. T. Pan, C. qinlingense Jien ex J. T. Pan.  相似文献   

15.
 To improve plant regeneration from oat anther culture, the basic medium, hormonal supplements and genotype effect were studied. Six of the 14 genotypes tested regenerated plants. Cultivars Kolbu, Katri, Stout and naked oat Lisbeth produced green plants, cultivars Virma and line OT 257 only albinos. The total number of green plantlets regenerated was 22, of which 13 (11 haploid, 2 doubled haploid) survived into the greenhouse, and 37 albinos. Regenerable-type embryos were induced from heat-pretreated anthers on media containing 2, 3 or 5 mg l–1 2,4-dichlorophenoxyacetic acid and 0.2 or 0.5 mg l–1 kinetin as hormonal supplements. 6-Benzylaminopurine promoted albino plant regeneration especially in W14 medium. Colchicine treatment was applied successfully to haploid regenerants. Received: 12 April 1999 / Revision received: 19 August 1999 / Accepted: 8 September 1999  相似文献   

16.
青藏高原的食虫类区系   总被引:3,自引:1,他引:3  
青藏高原的食虫类区系,迄今尚无专门的报道。仅在一些专著或区系文章中,对高原的食虫类或多或少的有所涉及。我们根据20来年对青藏高原综合考察的资料,和前人的研究成果,初步整理了本地区食虫类区系的有关资料,现报道如下。  相似文献   

17.
    
Traditionally, the oat crop (Avena sativa) has been neglected in a number of respects, cultivated in cropping areas not optimal for wheat, barley or maize. In recent years the interest in oats has increased, particularly because of its dietary benefits and therapeutic potential for human health. The uniqueness and advantages of naked oats over other popular cereals, due to its potentially valuable nutritional composition, have been well studied and reported, opening new market “niches” for oats. Despite the well‐documented benefits, the status of the oat crop is still fragile, due to many reasons. The area cultivated for the oat crop is much less compared with other cereals, and therefore commercial efforts in oat breeding are less. Oat groat yield is lower than other cereals such as wheat and the nutritious uniqueness has not been reflected in agreeable market prices. The same price still exists for both naked and conventional/covered oats in the world grain market. The absence of visible market competitiveness, and some of the oat biological drawbacks, including low grain yield, keeps the oat crop as a lower profitability minor crop. This review is intended to analyse and summarise main achievements and challenges in oat genetics, agronomy and phytopathology to find possible ways of oat improvement and future perspectives for oat breeding.  相似文献   

18.
Summary It is proposed that the first entity capable of adaptive Darwinian evolution consisted of a liposome vesicle formed of (1) abiotically produced phospholipidlike molecules; (2) a very few informational macromolecules; and (3) some abiogenic, lipid-soluble, organic molecule serving as a symporter for phosphate and protons and as a means of high-energy-bond generation. The genetic material had functions that led to the production of phospholipidlike materials (leading to growth and division of the primitive cells) and of the carrier needed for energy transduction. It is suggested that the most primitive exploitable energy source was the donation of 2H++2e at the external face of the primitive cell. The electrons were transferred (by metal impurities) to internal sinks of organic material, thus creating, via a deficit, a protonmotive force that could drive both the active transport of phosphate and high-energy-bond formation.This model implies that proton translocation in a closed-membrane system preceded photochemical or electron transport mechanisms and that chemically transferable metabolic energy was needed at a much earlier stage in the development of life than has usually been assumed. It provides a plausible mechanism whereby cell division of the earliest protocells could have been a spontaneous process powered by the internal development of phospholipids. The stimulus for developing this evolutionary sequence was the realization that cellular life was essential if Darwinian survival of the fittest was to direct evolution toward adaptation to the external environment.  相似文献   

19.
    
The genus Agrobacterium was created a century ago by Conn who included it in the family Rhizobiaceae together with the genus Rhizobium. Initially, the genus Agrobacterium contained the non-pathogenic species Agrobacterium radiobacter and the plant pathogenic species Agrobacterium tumefaciens and Agrobacterium rhizogenes. At the end of the past century two new pathogenic species, Agrobacterium rubi and Agrobacterium vitis, were added to the genus. Already in the present century these species plus Agrobacterium larrymoorei were reclassified into genus Rhizobium. This reclassification was controversial and for a time both genus names were used when new species were described. Few years ago, after a taxonomic revision based on genomic data, the old species A. rhizogenes was maintained in the genus Rhizobium, the old species A. vitis was transferred to the genus Allorhizobium and several Rhizobium species were transferred to the genus Agrobacterium, which currently contains 14 species including the old species A. radiobacter, A. tumefaciens, A. rubi and A. larrymoorei. Most of these species are able to produce tumours in different plants, nevertheless the genus Agrobacterium also encompasses non-pathogenic species, one species able to nodulate legumes and one human pathogenic species. Taking into account that the species affiliations to five Agrobacterium genomospecies have not been determined yet, an increase in the number of species within this genus is expected in the near future.  相似文献   

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