杨山牡丹的核型分析

本文首次报道了杨山牡丹的核型及银染间期细胞核仁数目。结果表明,银染核仁数最多为6个;核型简式为2n=2x=10=6m(3 SAT)+2 sm (1 SAT)+2 s t (2 SAT), 其中第1和第4对染色体短臂上具1个随体,第2和第5对染色体短臂上具1对随体。此外,对国产芍药属二倍体种的随体数目及其杂合性等问题进行了初步讨论。 Abstract:In the paper,the karyotype and silver staining of nucleolar numbers of P.ostii Hong et Zhang were reported for the first time.The results show that nucleolar numbers are six at the most and karyotype formula is 2n=2x=10=6m(3 SAT)+2sm(1 SAT)+2st(2 SAT)of P.ostii.There are one satellite on each short arms of the first and fourth chromosomes and two satellites on each short arms of the second and fifth ones respectiuely.In addition,the satellitic numbers and satellitic heterozygosity of diploid species of Paeonia in China are briefly discussed.     

毛莨在江西的核型变异

本文报道了毛茛(Ranunculus japonicus Thunb．)在江西发现的核型变异。R．japonicus 的基本核型为2n=14=6m+4sm十4st (2SAT);变异核型为2n=14十1B=6m+4sm+4st (2SAT)十1B和2n=14=6m+6sm(2SAT)+2st。核型变异表现在增加B染色体或第4对同源染色体异形及第6对随体染色体臂比变化。     

百合科六属十五种植物的细胞学研究

本文对云南西北部百合科6属15种的染色体和核型进行了报道。 (1)Clintonia udensis Trautv．et Mey间期核属于浓密分散型,前期染色体属于渐变型,分裂中期体细胞染色体2n=14=8m+4sm+2st(2SAT),核型不对称性属于2A型;(2)鹿药属四个种间期核属于复杂中央微粒型,前期染色体属于中间型,分裂中期体细胞染色体分别为Smilacina henryi(Baker)Wang et Tang,2n=36=12m+16sm+6st+2t(2SAT), 核型不对称性属于2C型;Smilacina fusca Wall., 2n=36=14m(2SAT)+12sm+10st(2SAT), 核型不对称性属于2B型; Smilacina tatsienensis(Franch．)Wang et Tang, 2n=36=22m+2sm+2st(2SAT), 核型不对称性属于2C型;Smilacina atropurpurea(Franch．)Wang et Tang,2n=36=18m+6sm(2SAT)+12st,核型不对称性属于2C型;(3)黄精属四个种的间期核属于复杂中央微粒型,前期染色体属于中间型,分裂中期体细胞染色体分别为Polygonatum kingianum Coll．et Hesml．,2n=30=12m(2SAT) +6sm+lst+2t, 核型不对称性属于2C型; Polygonatum cirrhifolium(Wall．) Royal,2n=30=10m+4sm+12st+4t, 3C型; Polygonatum curvistylum Hua, 2n=78=24m(2SAT)+14sm(6SAT)+40st, 核型不对称性属于3C 型; Polygonatum cathcartii Baker,2n=32=12m+6sm+10st+2t+2bs,核型不对称性属于2C型;(4)百合属,假百合属,豹子花属三个属的间期核和前期染色体形态相似,都属于复杂中央微粒型,前期染色体属于中间型,分裂中期体 细胞染色体分别为Lilium henricii Franch,2n=24=2m(2SAT)+2sm+10st+10t,核型不对称性属于3A型;Lilium bakerianum Coll．et Hesml．var． rubrum Stearn, 2n=24=4m (2SAT)+10st+10t(2SAT),核型不对称性属于3A型;Nomocharis bilouensis Liang 2n=24=2m(2SAT)+2sm+12st+8t,核型不对称性属于3A型;Nomocharis pardanthina Franch．,2n=24=4m(2SAT)+12st (2SAT)+8t,核型不对称性属于3A型;Nomocharis sauluensis Balf, f.,2n=24=4m(2SAT)+10st(2SAT)+10t,核型不对称性属于3B型;Notholirion campanulatum Cotton et Stearn2n=24=2m(2SAT)+2sm+14st(2SAT)+6t,核型不对称性属于3A型。     

武汉地区野豌豆属3种植物的染色体研究

本文报道了武汉地区野豌豆属3种植物的染色体数目及核型,结果如下:窄叶野豌豆为2n=2x=12=2sm+2st(SAT)+8st;小巢菜为2n=2x=14=10m+2sm(SAT)+2st;四籽野豌豆为2n=2x=14=4m+2sm(SAT)+8sm。本文还对野豌豆属染色体进化的有关问题进行了讨论。     

四种野生百合核型分析

对南川百合(Lilium rosthornii Diels)、青岛百合(L.tsingtauense Gilg)、山丹(L.pumilum DC.)和岷江百合(L.regaleWilson)等4种野生百合进行了染色体数目观察和核型分析。结果表明,核型除山丹为3A外,其余3种材料核型均为3B。核型公式分别为:南川百合2n=2x=24=4m(4SAT)+2sm+6st+12t;青岛百合2n=2x=24=8m(4SAT)+2sm(2SAT)+14t;山丹2n=2x=24=2m(2SAT)+6sm(2SAT)+4st(4SAT)+12t;岷江百合2n=2x=24=2m(2SAT)+2sm+6st+14t。核型不对称系数分别是81.68%、76.09%、80.34%和82.26%。其中,南川百合和青岛百合为国内首次报道。     

黄精属的细胞分类学研究Ⅰ.8个种的核型和进化

作者研究了中国产黄精属8个种的核型,结果如下:热河黄精,2n=22=14m(4SAT)+2sm(SAT)+6st;多花黄精,2n=22=8m+8sm(2sc)+6st(2sc);玉竹,2n=20=12m+8sm;小玉竹,2n=20=8m(2sc)+8sm+4st;长梗黄精,2n=16(18)=10m+4sm+2st;二苞黄精,2n=18=8m+10sm;黄精,2n=24=4m+8sm(2sc)+12st(2sc);卷叶黄精,2n=20=12m(2sc)+8sm。作者推测该属的染色体基数x=10。染色体数目进化的趋势是:非整倍性变异为主,整倍性变异为次;上升性变异为主,下降性变异为次。按照核型不对称程度,8个种的核型可分为三个等级。核型由对称向不对称进化是与染色体数目的进化趋势大体上相关的。     

黄精属的细胞分类学研究——Ⅱ.8个种的核型和进化

作者研究了中国产黄精属8个种的核型,结果如下:热河黄精,2n=22=14m(4SAT)+2sm(SAT)+6st;多花黄精,2n=22=8m+8sm(2sc)+6st(2sc);玉竹,2n=20=12m+8sm;小玉竹,2n=20=8m(2sc)+8sm+4st;长梗黄精,2n=16(18)=10m+4sm+2st;二苞黄精,2n=18=8m+10sm;黄精,2n=24=4m+8sm(2sc)+12st(2sc);卷叶黄精,2n=20=12m(2sc)+8sm。作者推测该属的染色体基数x=10。染色体数目进化的趋势是:非整倍性变异为主,整倍性变异为次;上升性变异为主,下降性变异为次。按照核型不对称程度,8个种的核型可分为三个等级。核型由对称向不对称进化是与染色体数目的进化趋势大体上相关的。     

杨属派间核型比较研究

对杨属五派代表种的核型进行了分析,各代表种核型公式如下:欧洲山杨(白杨派)2n=2x=38=21m(2SAT)+4sm+13st(1SAT);小叶杨(青杨派)2n=2x=38=1M+26m(1SAT)+8sm(1SAT)+1st+2t(1SAT);大叶杨(大叶杨派)2n=2x=38=2M+22m+8sm+6st;胡杨(胡杨派)2n=2x=38=2M+23m+3sm+10st(2SAT);箭杆杨(黑杨派)2n=2x=38=3M+29m(2SAT)+5sm+1st。杨属派间核型差异主要表现在中部与次中部着丝点(M,m)和近端部与端部着丝点(st,t)染色体数目上。白杨派和胡杨派具较多的st、t染色体,核型不对称系数比其它派高。按Stebbins理论白杨派和胡杨派属进化类型。     

东北地区野豌豆属Vicia L.物种生物学研究 Ⅲ.广布野豌豆类群细胞学初步观察

本文首次报道了国产二倍体广布野豌豆的核型, 其核型公式分别为2n=12=2m+8sm(2SAT)+2st, 2n=14=2m+8sm(2SAT)+4st。其中2n=14的染色体计数系我国新纪录。为修订国产广布野豌豆的分类处理提供了必要的细胞学依据。     

黄精族4属6种的核型报道

本文报道四川、陕西、河北的百合科黄精族4属6种的染色体数目和核型。Disporum megalanthum 2n=16=2m(1SAT)+6sm(1SAT)十8st(3SAT)and 2n＝16=2m(1SAT)+8sm(3SAT)+6st,3B型;Disporopsis pernyi 2n＝40=23m(2SAT)+15sm(2SAT)十2st+2t(2SAT), 2B型;Disporopsis aspera 2n=40=30m十8sm(2SAT)+2t(2SAT),2B型;Maianthemum bifolium 2n=36＝20m＝10sm十4st十2t(2SAT),2B型;Palygonatum odoratum 2n=20=10m+10sm(3SAT),2B和2n＝20＝12m(4SAT)+8sm(2SAT), 2B型;Polygonatum humile 20=20+10m(2SAT)十6sm(2SAT)+4t,2B型。从染色体角度,并联系形态特征,对Disporum属中分别见于东亚和北美的两个类群的关系作了讨论。也讨论了Disporopsis种间在核型不对称趋势与形态特化之间可能的关系。 本文还指出Polygonatum odoratum和Polygonatum humile种内核型的多变性。     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.     

杆状病毒出芽病毒粒子膜融合蛋白的研究进展

杆状病毒是一类感染节肢动物的病原微生物,其基因组为双链环状DNA,大小为80～180kb.     

Inception of the Modern Public Health System in China and Perspectives for Effective Control of Emerging Infectious Diseases: In Commemoration of the 140th Anniversary of the Birth of the Plague Fighter Dr. Wu Lien-Teh

In this article, we systematically review Dr. Wu Lien-Teh's academic achievements and outstanding contributions in the prevention and control of the plague epidemic in northeast China and introduce the development of the earliest public health epidemic prevention system in China in order to commemorate the 140th anniversary of Dr. Wu Lien-Teh's birth. We hope that this article will provide insights into the effective prevention and control of emerging infectious diseases as well as the current worldwide pandemic of COVID-19, facilitating the improvement and development of public health systems in China and around the globe.