百合‘Siberia’בManissa’种间杂交后代的染色体核型分析

以东方百合杂种系(Oriental hybrids group)品种‘Siberia’为母本,OT杂种系(interspecific hybrids betweenOriental and Longiflorum/OT group)品种‘Manissa’为父本杂交获得种间杂交F1代,对亲本及F1代株系的染色体数目和形态特征进行了分析。结果显示,母本东方百合‘Siberia’为二倍体即24条染色体,而父本‘Manissa’是高度杂合后代,为三倍体即36条染色体。杂交F1代的8个株系中有6个株系为二倍体即24条染色体,有2个株系为非整倍体,染色体条数分别为25和26条。母本‘Siberia’的核型为4m(1SAT)+10st(1SAT)+10t,父本‘Manis-sa’的核型为3m+18st(1SAT)+15t(1SAT),均属3B型。杂种F1代核型出现了多种类型,其中株系a、b、h为3B型,株系c、d、e、f为3A型,株系g为4B型。与亲本染色体形态相比,F1代株系出现了随体及端部着丝点染色体较多等染色体形态结构特征,而亲本没有这些特征。从染色体的形态、随体来看,子代为真杂种,在遗传上均偏向于母本。     

4个洋水仙品种的核型分析

采用常规压片技术对4个洋水仙品种的体细胞染色体数目和核型进行了分析。结果显示:4个品种的染色体组成复杂多样,其核型公式依次为‘哈韦拉’2n=2x=14=8sm+6st;‘面对面’2n=3x=24=2m+15sm+7st;‘快活’2n=3x=24=3m+13sm+8st;‘花唱片’2n=4x=28=8m+16sm+4st,其核型不对称系数依次为75.19%、72.73%、74.25%和71.03%,核型类型分别为3B、3B、3B和3A。从4个洋水仙品种来源等方面的资料分析了这些品种倍性及其可能的育种价值,其中‘哈韦拉’为二倍体种间杂种,‘面对面’和‘快活’为异源三倍体;‘花唱片’为四倍体。     

4个火焰兰属内及属间杂交新组合F_1代核型分析

采用染色体常规压片法对兰科Orchidaceae火焰兰属Renanthera内3个及与万代兰属Vanda间1个共4个杂交新组合F1代核型进行研究。结果表明:4个杂交新组合F1代中,麒麟火焰兰R.coccinea‘Qi Lin’、麒麟火焰兰×中华火焰兰R.sinica、(云南火焰兰R.imschootiana×中华火焰兰)×麒麟火焰兰、云南火焰兰×小花万代兰Vanda coerulescens的染色体数目依次为37、57、54、38;核型公式分别为:2n=2x+1=37=22m(2sat)+15sm(4sat)、2n=3x=57=39m(3sat)+12sm(3sat)+3st+3T、2n=3x=54=9M+27m+12sm+3st+3T、2n=2x=38=6M+14m+16sm+2T。核型不对称系数依次为:48.76、60.50、51.60、65.87。按Stebbins分类,均为"2B"型。4个新组合中,染色体存在非整倍体(三体)及多倍体(3×)现象。     

木兰科3个杂交组合及其亲本的核型研究

研究了木兰科（Magaoliaceae）3个杂交组合的亲本和杂交后代的核型。结果表明，云南含笑（Michelia yunnanensis）、灰岩含笑（Michelia calcicola）及其杂交组合A的核型分别为2n=2x=38=36m＋2sm、2n=2x=38=34m＋4sm和2n=2x=38=26m＋12sm；紫花含笑（Michelia crassipes）及其与云南含笑杂交组合C的核型分别为2n=2x=38=32m＋6sm和2n=2x=38=24m＋12sm＋2st；山玉兰（Mognolia delavayi）、广玉兰（Mognolia grondiflora）及其杂交组合U的核型分别为2n=2x=38=28m＋10sm、2n=6x=114=88m＋lOsm＋16st和2n=4x=76=57m＋15sm＋4st。杂交组合的核型与理论核型存在明显的差异，可能是在杂交组合的形成过程中，来自亲本的染色体发生了结构变异。     

月季种质资源的倍性变异及核型多样性研究(英文)

采用常规压片法对包括5个蔷薇野生种、8个古老月季及9个现代月季品种共22份月季种质资源进行核型分析。供试材料共有3种不同倍性:5个野生种中粉团蔷薇为三倍体(2n=3x=21),其他4个材料为二倍体(2n=2x=14);9个现代月季品种均为四倍体(2n=4x=28);而古老月季品种中包含二、三、四倍体3种倍性。22份材料中共发现4种不同类型的核型,在野生种中为1A、2A;古老月季中为1A、2A、1B;现代月季中为1A、1B、2B。另外,供试材料在核不对称系数、着丝粒指数、随体数目及位置、染色体相对长度组成等方面差异较大,说明在月季种质资源中存在着丰富的核型多样性。     

甜菊不同杂交组合结实率及其F1代萌发和生长及对NaCl耐性的比较

以甜菊(Stevia rebaudiana Bertoni)的耐盐性较强品种‘中山3号’和‘守田2号’及R-A高含量品种‘中山4号’和‘守田3号’为亲本配置7个杂交组合并获得杂交种子,对种子结实率和发芽率及F1代幼苗的存活率进行统计分析,在此基础上采用砂培和水培方法比较了亲本及F1代扦插苗对NaCl胁迫的耐性.结果表明:品种间杂交组合的结实率均显著高于同系列品种间杂交及自交组合,其中‘守田2号’ב中山3号’杂交组合的结实率最高,为74.9％;7个杂交组合F1代的种子发芽率为63.8％ ～ 89.0％,差异明显;‘守田2号’ב中山4号’杂交组合F1代幼苗存活率相对较低(79.80％),其他杂交组合F1代幼苗存活率均在93％以上.砂培条件下,用100 mmol·L-1NaCl胁迫7d,各杂交组合F1代扦插苗的存活率差异不显著;随NaCl胁迫时间的延长各杂交组合F1代扦插苗的存活率均明显下降;胁迫28 d,‘守田2号’ב守田 3号’杂交组合以及‘中山3号’自交组合F1代扦插苗的存活率显著高于其他杂交组合.水培条件下,用100、150、200和250 mmol·L-1 NaCl胁迫14 d,‘守田2号’ב中山3号’、‘中山3号’ב守田2号’和‘中山3号’ב守田3号’3个杂交组合F1代扦插苗的存活率均显著高于其耐盐亲本及其他杂交组合.研究结果说明:通过杂交提高甜菊耐盐能力是可行的,而亲本的耐盐能力及亲本配置对杂交后代目标性状有较大影响;‘中山3号’ב守田2号’、‘守田2号’ב中山3号’和‘中山3号’ב守田3号’是耐盐性较强的甜菊优良杂交组合.     

香水月季(Rosa odorata Sweet)不同变种的染色体及核型分析

采用常规压片法对采自11个地点的4个变种进行了以染色体形态和倍性为主的核型分析。结果表明:(1)香水月季原变种是2倍体,核型公式为:2n=2x=14=12m+2sm,核型为1A。(2)大花香水月季4个居群的染色体形态很相似,都是2倍体,核型全为1A,核型公式均是2n=2x=14=12m+2sm,居群间差异主要表现在染色体组的相对长度构成上。(3)桔黄香水月季是2倍体,核型公式为2n=2x=14=10m+4sm,核型为1A。(4)来自不同地方的粉红香水月季在染色体数量和形态上有较大的差异。木家桥和永春的是3倍体,核型公式分别为2n=3x=21=18m+3sm和2n=3x=21=21m;红桥、富民和小河的是2倍体,核型公式分别为2n=2x=14=12m+2sm、2n=2x=14=10m+4sm和2n=2x=14=12m+2sm;除富民的核型为1B外,其他地方的核型均是1A。基于研究结果,讨论了香水月季的核型特征、细胞遗传分化模式、丰富的变异及其在育种中的应用。     

3个马铃薯杂种优良株系的核型及SSR分析

为明确‘费乌瑞它’ב陇薯3号’杂种F1优良无性株系A1和A3及‘费乌瑞它’×J07-6杂种F1优良无性株系C2在染色体及DNA水平上的遗传差异,利用根尖染色体制片技术和SSR分子标记技术,对这3个优良株系的核型及SSR指纹特征进行分析。结果表明:(1)株系A1、A3和C2均为四倍体(2n=4x=48),其核型类型分别为2B、1B和1A;株系A1和A3核型公式均为2n=4x=48=36m+12sm,C2核型公式为2n=4x=48=48m。(2)利用筛选出的10对SSR适宜引物PCR扩增得到50个多态性位点,多态性位点百分率为79.37%。(3)建立了3个马铃薯杂种优良株系及其亲本的SSR指纹图,并以遗传距离(GD值)0.45为基准,将6个材料分为3类:母本‘费乌瑞它’、株系A1和父本‘陇薯3号’聚为一类,株系A3和C2聚为另一类,父本J07-6单独列为一类。     

马铃薯杂种F1的SSR鉴定

为选育抗黑痣病、高产优质的马铃薯新品种,选用引进品种‘大西洋’分别与‘陇薯6号’、‘陇薯7号’杂交,获得了杂种F1代,利用SSR标记技术对‘大西洋’与‘陇薯6号’的42个杂种F1、‘大西洋’与‘陇薯7号’的9个杂种F1单株进行了鉴定。从59对SSR引物中筛选出2对在亲本间存在差异、扩增稳定、条带清晰的引物S184和STM1049,用于‘大西洋’ב陇薯6号’杂种F1、‘大西洋’ב陇薯7号’杂种F1及其亲本的基因组DNA扩增。SSR带型分析显示,杂种F1的SSR带型呈双亲互补型、缺失型、父本型和母本型4类,依据带型特征鉴定出供试的51个马铃薯杂种F1单株均为真杂种,表明SSR分子标记技术用于马铃薯杂种真实性鉴定是可行的。该研究可为进一步开展马铃薯杂交后代目标性状优异株系选育提供依据。     

新疆疏花蔷薇的核型分析与探讨

采用常规压片法,对从新疆采集的5份疏花蔷薇进行了核型分析.结果表明:疏花蔷薇包括二倍体(2n=2x=14)和四倍体(2n=4x=28)两种核型;核不对称系数为55.14％～60.11％;核型分类包括1A、2A、1B等3种类型;分析认为,不同倍性的出现与种质在不同区域、不同生境下生长有一定相关性.其中疏花蔷薇5号为四倍体,核型信息与其他材料差异明显,核不对称系数最大,核型分类也最进化.研究结果支持刘士侠等对其表型分类的划分,即托木尔蔷薇作为疏花蔷薇在新疆的特殊地理种;而4号材料也支持《新疆植物志》的分类,即建议喀什疏花蔷薇作为疏花蔷薇的变种.     

Foreign exploration for Scirtothrips perseae Nakahara (Thysanoptera: Thripidae) and associated natural enemies on avocado (Persea americana Miller)

Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising.     

Taxonomic status of the species of the green algal genusNeochloris

Komárek has recently reviewed the various species assigned to the green algal genusNeochloris Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia. Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class.     

Die GattungKarschia — Bindeglied zwischen bitunicaten Ascomyceten und lecanoralen Flechtenpilzen?

The genusKarschia, in the earlier sense, including saprophytes and parasites on lichens, has been thought to be a non-lichenized parallel genus of the lichen genusBuellia. Modern workers included it on the one hand inBuellia, on the other hand combined it with bitunicate ascomycetes. It is now proved thatKarschia is heterogeneous and contains but superficially similar members both of the genusBuellia of theLecanorales and of typical or masked bitunicateAscomycetes. Therefore, it can not be regarded as a link betweenLecanorales andDothideales. The type species ofKarschia belongs to theDothideales.

     

Systematic significance of mature embryo of bamboos

The mature embryo of seven species belonging to five genera of Indian bamboos is described. In all these the basic pattern of embryo organisation is same: the scutellar and coleoptilar bundles are not separated by an internode, the epiblast is absent, the lower portion of the scutellum and the coleorhiza are separated by a cleft and the margins of embryonic leaves overlap. The features unique to fleshy fruited bamboos are: presence of a massive scutellum, the juxtaposition of plumule and radicle and the occurrence of a bud in the axil of the coleoptile. The fleshy fruit bearing bamboos should be classified into one group, the tribeMelocanneae. Evidence is provided to recognise additional groups in the subfamilyBambusoideae.     

Entwicklungsgeschichte und Ultrastruktur von Pollenkitt und Exine bei nahe verwandten entomophilen und anemophilen Angiospermensippen derAlismataceae,Liliaceae, Juncaceae,Cyperaceae, Poaceae undAraceae

Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.

     

New geographical distribution and host records of rust fungi from northern Thailand

Ten species of rust fungi (Crossopsora 2, Maravalia 1, Pileolaria 1, Puccinia 1, Ravenelia 1, Sphaerophragmium 1, Uredo 2, and Uromyces 1) are newly recorded together with six new host plants in Thailand.Contribution no. 194, Laboratory of Plant Parasitic Mycology, Graduate School of Life and Environmental Sciences, University of Tsukuba, Japan