云贵高原多星韭二倍体—四倍体分布格局研究

采用染色体压片技术对云贵高原17个多星韭居群,共412株个体进行染色体数目和核型研究。结合已有的细胞学资料,对云贵高原多星韭多倍体分布格局进行了研究。9个二倍体居群、6个二倍体与四倍体混生居群分布于云南中部至西北部,12个四倍体居群分布于整个云贵高原。二倍体除香格里拉d和保山居群核型类型为3A型外,其余均为2A型,四倍体除会泽和赫章居群为2 B型外,其余均为2A型。云南西北部四倍体核型不对称指数低于其它分布区,推测该地区四倍体可能起源较早。多星韭二倍体与四倍体核型类型和形态并无明显差异,表明多星韭四倍体可能为同源多倍体。     

云贵高原多星韭二倍体—四倍体分布格局研究

采用染色体压片技术对云贵高原17个多星韭居群,共412株个体进行染色体数目和核型研究。结合已有的细胞学资料,对云贵高原多星韭多倍体分布格局进行了研究。9个二倍体居群、6个二倍体与四倍体混生居群分布于云南中部至西北部,12个四倍体居群分布于整个云贵高原。二倍体除香格里拉d和保山居群核型类型为3A型外,其余均为2A型,四倍体除会泽和赫章居群为2 B型外,其余均为2A型。云南西北部四倍体核型不对称指数低于其它分布区,推测该地区四倍体可能起源较早。多星韭二倍体与四倍体核型类型和形态并无明显差异,表明多星韭四倍体可能为同源多倍体。     

自然三倍体韭的发现

韭(Allium tuberosum Rottl. ex Spreng.) 原产我国,由于抗逆性强,栽培容易,又具有特异的辛香气味,自古以来就是群众喜爱的蔬菜品种之一。据文献记载,栽培的韭有二倍体和四倍体两类,分别由野生的二倍体韭和四倍体韭经长期驯化而来。栽培的四倍体韭产量比二倍体高。目前各地的商品韭多为四倍体,二倍体已不多见,而     

云南宾川县鸡足山地区多星韭种群分化的研究

对鸡导山地区７个多星韭种群的生物生态学特性进行了比较全面的研究。结果表明;鸡足山地区的多星韭有二倍体和四倍体２种倍性。多星韭二倍体比四倍体更能忍受较恶劣的环境条件。二倍体多星韭生境单一,种群分化不明显;四倍体多星韭生境多样,种群间变异丰富,分化强烈。     

葱属根茎组8种21居群植物的核型研究

对葱属根茎组Allium sect.Rhiziridium的8种21个地方居群的核型进行研究,以期为解决该组的种间亲缘关系和物种进化机制提供依据。贺兰韭A.eduardii和阿拉善韭A．flavovirens2个种的核型以及辉韭A．strictum的六倍体核型均属首次报道。研究结果表明：贺兰韭A.eduardii、阿拉善韭A.tlavovirens、北韭A.lineare、蒙古韭A.mongolicum和滩地韭A．oreoprasum的各居群均为二倍体,核型类型为Stebbins的2A型;韭A．tuberosum和野韭A.ramosum的各个居群均为四倍体,核型类型为2A型：辉韭A．Jtrictum的4个居群均为六倍体,核型类型为2B型。通过研究可以得出如下推论：（1）该组植物中存在着大量的多倍体或多倍体系列,染色体数目变化与物种进化具有密切相关性,多倍化可能是根茎组植物核型进化的重要机制之一;（2）随体染色体多为st或t染色体,均位于短臂末端;（3）可以认为辉韭是以增加倍性来克服该物种扩大新的生存空间所带来的困难;（4）现今栽培的韭可能是由野生的二倍体韭和四倍体韭经过长期人工驯化而来的,现今栽培的三倍体韭可能是二倍体韭和四倍体韭杂交而来,并且以无性繁殖方式保存三倍体类群的存在。     

六倍体多星韭的发现及多星韭种内倍性组成及演化的分析

采用染色体常规制片技术,对云南西北部和中部地区11个多星韭居群进行了细胞学分析。结果显示:(1)云南西北部多星韭二倍体、四倍体混合分布的太子阁和华首门四倍体居群中发现了三倍体(2n=3x=21),核型公式分别为:2n=3x=21=[6m(2sat)+8sm]+(3m+4sm)和2n=3x=21=[4m(2sat)+10sm]+(2m+4sm+lst)。三倍体含2条随体染色体,它的21条染色体含2个同源染色体组和一个与它们同源性稍差的染色体组。(2)在云南中部的多星韭四倍体居群中首次发现了六倍体,核型公式为2n=6x=42=15m(3sat)+27sm,核型类型2A。(3)结合核型特征及地理分布对多星韭三倍体和六倍体的成因进行分析,提示多星韭三倍体来源于二倍体与四倍体的杂交,六倍体是通过四倍体产生的未减数配子(n=4x=28)与正常减数配子(n=2x=14)的结合形成的。本研究结果支持多星韭的分化中心是云南西北部高海拔地区的观点,并结合前人的研究和本工作的结果,对多星韭种内的倍性组成和演化进行了分析和讨论。     

两种生态型空心莲子草对莲草直胸跳甲发育和繁殖的影响

【目的】评价空心莲子草Alternanthera philoxeroides 2种生态型食物对莲草直胸跳甲Agasicles hygrophila生长发育和繁殖的影响。【方法】建立莲草直胸跳甲在水生型和旱生型空心莲子草上的实验种群两性生命表。【结果】2种生态型空心莲子草对莲草直胸跳甲2龄和3龄幼虫的历期、产卵前期、产卵期、雌虫寿命、雄成虫寿命和繁殖力的影响无显著差异,但取食水生型空心莲子草的莲草直胸跳甲具有较短的蛹历期（6.28 d）、较高的幼虫期存活率（99.00%）和较高的成虫前期存活率（95.00%）;取食旱生型空心莲子草的莲草直胸跳甲在内禀增长率和周限增长率都显著低于水生型食物,但莲草直胸跳甲的净增殖率（R_0）和平均世代周期（T）在旱生型和水生型食物间并无显著差异。【结论】与旱生型空习莲子草相比,水生型空心莲子草是莲草直胸跳甲的较适宜食物,但旱生型空心莲子草并不显著影响莲草直胸跳甲的发育和繁殖。     

葱属合被组植物的引种栽培及染色体观察

对国产葱属合被组（ＡｌｌｉｕｍＳｅｃｔ．Ｃａｌｏｓｃｏｒｄｕｍ）的长梗韭（Ａ．ｎｅｒｉｎｉｆｌｏｒｕｍ）和合被韭（Ａ．ｔｕｂｉｆｌｏｒｕｍ）进行了引种栽培实验及染色体观察,结果表明：将原野生状态下生长的这２个种转为人工条件下栽培,长势良好,能正常开花结实;体细胞染色体数显示,长梗韭四个居群均为二倍体２ｎ＝２ｘ＝１６,合被韭的一个居群为二倍体２ｎ＝２ｘ＝１６,另一个居群为四倍体２ｎ＝４ｘ＝３２,所不同的是长梗韭染色体带有一对中间随体,而合被韭染色体则带有一对或二对末端随体。此外,首次发现合被韭存在有二次生长现象。     

中国水韭属植物的染色体数目及其分类学意义

利用细胞学方法观察统计了中国4种水韭属Isoestes植物的染色体数目。结果发现4个种的染色体基数均为x=11,其中高寒水韭I．hypsophila Hand.-Mazz．为2n=22,为首次报道;台湾水韭 I．taiwanensis DeVol为2n=22;中华水韭I．sinensis Palmer 2n=44为四倍体;而产于云南贵州一带并一直被当作是宽叶水韭I．japonica A．Br．的水韭属植物2n=22,与文献报道的宽叶水韭(2n=66,67,77,87,88,89)完全不同,应重新予以认识和评价。依据本文和其他相关的研究结果,对东亚水韭属植物进行了分类处理。     

中国西南葱属10种20居群的核型研究

采用常规压片法,对采自中国西南地区的10种20个居群葱属（Allium L．）植物的根尖有丝分裂中期进行了观察,10种葱属植物分别为峨眉韭（Alliumomeiense）、多星韭（A．wallichii）、大花韭（A．macranthum）、韭（A．tubero—sum）、高山韭（A．sikkimense）、天蓝韭（A．cyaneum）、西川韭（A．xichuanense）、野黄韭（A．rude）、野葱（A．chrysanthum）和真籽韭（A．eusperma）。供试类群中,核型类型为2A、2B和2c,其中2c为首次报道;染色体基数为7、8、11;5个种中存在多倍体,其中天蓝韭的5倍体居群为首次报道;6个种存在随体杂合现象。通过观察发现峨眉韭的核型不对称性与海拔高度存在相关性;四倍体大花韭的核型演化伴随着st染色体短臂的断裂和丢失。结合核型、形态学和繁育制度等特征,对部分类群的进化和组一级分类等级及其归属问题进行了探讨。     

基于AFLP分子标记技术的黑花韭与多星韭遗传多样性与亲缘关系分析

采用AFLP分子标记技术分析了分布在滇中、滇西、滇西北的3个黑花韭居群、3个二倍体多星韭居群和6个四倍体多星韭居群的遗传多样性与亲缘关系.结果表明,12个居群在DNA水平上已发生明显分化.居群间的基因分化系数(GST)为0.444.由GST计算的居群间基因流(Nm)为0.625,表明居群间部分基因流动受阻.12个居群间...     

Intraspecific differentiation of Allium wallichii (Amaryllidaceae) inferred from chloroplast DNA and internal transcribed spacer fragments

In the present study, we used two chloroplast DNA (cpDNA) fragments (trnL-F and rps16) and the nuclear ribosomal internal transcribed spacer (ITS) sequence data to examine intraspecific differentiation and phylogeographical history of Allium wallichii. Based on wide scale sampling (28 populations and 174 individuals) across the entire distribution range of this species, 33 cpDNA haplotypes and 25 ITS ribotypes were detected in our investigation. These cpDNA haplotypes were divided into three major lineages, which was further supported by the ITS phylogenetic results. High haplotype/ribotype diversity and population differentiation, together with most of the haplotypes/ribotypes being exclusive to single populations, implied restricted gene flow among populations and significant geographical isolation. Nearly all populations with high haplotype/ribotype diversity were found in the Hengduan Mountain Region (HMR), whereas the populations of the Himalayas and Nanling Mountains showed a lower level, suggesting the HMR might serve as a potential divergence center for A. wallichii. The main lineages of A. wallichii diverged from each other between Mid–Late Pliocene and Early Quaternary based on two sets of molecular markers, indicating that the Quaternary climatic fluctuation could not have contributed greatly to the divergence of the main lineages of A. wallichii. Instead, the intricate topography and heterogeneous habitats resulting from the drastic uplift of the Qinghai–Tibet Plateau from the Late Pliocene could be responsible for the intraspecific differentiation of A. wallichii. The present study further highlights the importance of geographic isolation and habitat heterogeneity in shaping and maintaining high species diversity within the HMR.     

青海青甘韭9个居群的核型

本文研究了青海葱属青甘韭 9个居群的染色体数目和核型。其中分布于湟源、西宁和共和海拔相对较低的地区的居群为 2倍体 ,核型公式为 2n =2x =16 =14m 2st (2SAT) (湟源居群和西宁居群 ) ,2n =2x =16 =12m 2sm 2st (2SAT) (共和居群 ) ;分布于玛沁、玉树、囊谦等高海拔地区的居群为 4倍体 ,核型公式为 2n =4x =32 =2 8m 4st (2SAT) (玉树居群 1和囊谦居群 1) ,2n =4x =32 =2 4m 4sm 4st (玛沁居群和玉树居群 3)和 2n =4x =32 =2 6m 2sm 4st (玉树居群 2 ) ;囊谦一个生长在林下的居群为 8倍体 ,2n =8x =6 4 =54m 2sm 8st。讨论了居群间的核型分化和倍性与分布的关系。     

Studies on the Karyotype of 5 Samples of Allium Sect. Bromatorrhiza Ekberg

The karyotypes of 5 samples in Allium Sect. Bromatorrhiza Ekberg were analysed in this paper. In Allium wallichii Kunth, the first sample is a diploid, with genome formula is AA and karyotype formula is K(2n)=2x=14=2m(SAT)+2m+10sm. The second is an autotetraploid, with genome formula AAAA, karyotype formul K(2n)=4x=28=2m(SAT)+6m+20sm. These two karyotypes belong to “3A”. The two karyotypes of A. wallichii Kunth are similar in morphology, though different in ploidy. In Allium hookeri Thwaites, the first sample is a dibasic autoallotriploid. Its genome formula is AAB₁; the basic number of the genome A is 7 and that of the genome B₁ is 8. The karyotype formula is K(2n)=2x+x'=22=(12sm+2t)+(1m+4sm+1st+2t). The second is also an autoallotriploid. The genomes in pairs are similar to those in the first sample in size and morphology of chromosomes. However, the unpaired genome differs from the first one apparently. Therefore, its genome formula is AAB₂, and karyotype formula is K(2n)=2x+ x'=22=(12sm+2t)+(3m+1sm+2st+2t). The third is doubling of the first karyotype. It is an autoallohexaploid, with genome formula AAAAB₁ B₁ and karyotype formula K(2n)=4x+2x'= 44= (24sm+4t) + (2m+8sm+2st+4t). These three karyotypes belong to “3A”.     

韭不同倍性及其非整倍体的ITS序列变异研究

对不同倍性及其非整倍体韭Allium tuberosum和野韭Allium ramosum核糖体DNA的内部转录区(ITS)进行了PCR扩增和克隆,并测定10个ITS1和ITS2的序列,用ITS1 ITS2的序列探讨Allium tuberosum和Allium ramosum的系统发育关系。研究表明,Allium tuberosum与Alli-um ramosum种间的平均Kimura遗传距离仅为0．0146,二者是一对近缘种。虽然韭经历了长期的人工选择和自然选择,但与野韭的分化仍然较小。韭不同倍性及其非整倍体之间,其ITS序列亦无明显差异。     

国产葱属合被组植物的核型及亲缘关系研究

本文对国产百合科葱属合被组(Sect．Caloscordum)的长梗韭(Allium neriniflorum Baker)和合被韭(A.tubiflorum Rendle)共6个居群进行了调查和栽培实验,在此基础上,从细胞学、形态解剖学等角度对各居群进行了研究,通过核型分析及形态比较认为：将合被组置于葱属中更合理。种的划分可根据核型中随体的类型、小花梗的长度、植物在一年的生长周期中是否有明显的二次生长现象为标准来划分。每室胚珠的多少只能反映出二倍体与四倍体的区别,不能作为分种指标。本文有关合被韭的核型研究的报道在国内尚属首次。     

Studies on Karyotypes and Phylogenetic Relationship of Allium Sect. Caloscordum (Liliaceae) from China

The present papar is a report on cytotaxonomical studies of Allium Sect． Caloscordum(Liliaceae)from China． Six populations of A. neriniflorum and A．tubiflorum were introduced from Shaanxi,Hebei(Beijing),Liaoning and Heilongjiang．Based on the introduction and cultivated experiment, the authors made a karyotype analysis and a morphological comparison of the six populations． The results are as follows． Except the population 5 (Baihuashan,Beijing),which was found to be tetraploid 2n＝4x＝32,all the populations were dipliod 2n=2x＝16． There were two types of satellites： terminal and intercalary． The basic number,the karyotypes as well as the types of satellites in Sect． Caloscordum were the same as those in the other sections of Allium． In the populations 1, 2, 3 and 4(Daheshan,Jinxia County,Liaoning;Taikang County, Heilongjiang; Chengde to Huaqing, Hebei; Liulimao, Huairou,Beijing．), the sixth pair of chromosomes had a pair of intercalary satellites,the mean length of pedicels is about 7 cm and the plant had no two-growth cycle．In the populations 6 (Xianyunei, Huashan, Shaanxi)： the eighth chromosome pair had a pair of terminal satellites, the pedicel was shorter,with the mean length 2．39 cm,and the plant had two-growth cycle． In the tetraploid population 5; fourteenth and sixteenth chromosome pairs both had a pair of terminal satellites,the mean length of pedicel was 2．39 cm and the plant had the two-growth cycle．According to the results,the authors keep Sect． Caloscordum in the genus Allium and recognize two species in China in the section; the populations 1, 2, 3 and 4 belong to A．neriniflorum,and the populations 5 and 6 to A．tubiflorum．Our observation on dissecting ovary showed that there were 2～11 ovules per locule;the diploid populations mainly had 5 ～6 ovules per locule,while the tetraploid ones mainly had 4 ovules per locule．Therefore, the number of ovules per locule is not a reliable character for classifiction but it may be useful in distinguishing diploid from tetraploid．However,we consider that the satellite type,the pedicel length and whether the plant has two-growth cycle are the diagnostic features for the species of Sect．Caloscordum．