六个石蒜居群的核型及四倍体石蒜的发现

染色体与核型的变化是植物系统发育和进化的一个重要方面。石蒜属Lycoris植物特别是石蒜L.radiata在染色体数目和核型上存在较大的变异。通过对不同居群的石蒜核型研究,可以为石蒜和石蒜属植物的核型演化及演化机制提供一些重要的基础资料。本文对分布于中国安徽省和浙江省的6个石蒜居群进行了细胞学研究。结果表明,6个石蒜居群的染色体数目和核型分别为：霍山居群2n=44=28st＋8t＋8T,2n=22=6st＋12t＋4T;黄山居群2n=22=22t,2n=22=18st＋4t,2n=21=12st＋7t＋2T;滁州居群2n=33=33t;马鞍山居群2n=33=18st＋15T,2n=25=1m＋20st＋2t＋2T;宣城居群2n=22=20st＋2T,2n=21=1m＋20st;杭州居群2n=22=12st＋4t＋6T,2n=21=18st＋3t。其中,部分居群的核型类型为首次报道;并首次发现了四倍体的石蒜居群。此外,对石蒜的核型进化和多倍体起源进行了初步探讨。     

二倍体石蒜在安徽发现

本文以根尖细胞为材料,观察了石蒜Lycoris radiata(L′Her．)Herb．三个不同居群植物的染色体数目和核型,发现石蒜为一复合体,包括两种不同类型：(1)三倍体类型,主要包括一群以鳞茎无性繁殖的园艺栽培植株,其染色体数目和核型为2n＝33=33t(st),属“4A”核型,且极其稳定。(2)二倍体类型,主要包括一群野生植株,变异较大,我们发现有下列几种情况：一是芜湖产石蒜(L．radiata)的野生材料,其染色体数目和核型为2n=21+1B=1m+12st+8t+1B,属“3A”核型,在石蒜种内迄今未见有类似报道;另一是黄山产野生材料,观察到两个细胞型,绝大多数细胞为2n=22＝12st+1Ot,极个别细胞出现2n＝22+1B=6st+14t+2T+1B的情况,均属“4A”核型。芜湖和黄山野生材料的染色体数目和核型均为首次报道。石蒜(L．radiata)的二倍体类群也是首次在安徽发现。     

安徽产石蒜两个居群的核型研究

观察了石蒜(Lycoris radinta)两个不同居群植物的染色体数目和核型,发现野生石蒜在一个植株的不同根尖细胞里,存在两种倍性的细胞,如生于宣城敬亭山的居群既有正常三倍体：2n=33=18st 15T,属于“4A”核型;还有异常二倍体：2n=20 1B=2st 18T 1B,属于“4B”核型;生于芜湖的居群核型为：2n=20 1B=lm 9T 4t 6st 1B和2n=20 1B=1M 9T 10st 1B,属于“3B”和“3C”核型。     

三倍体换锦花在安徽发现

本文对分布于安徽江南和江淮两个地区野生居群的换锦花Lycoris sprengeri进行了细胞学研究, 发现换锦花为一复合体,包括两个不同类型：(1)三倍体类型,分布于安徽马鞍山市采石的野生居群,其 染色体数目和核型为2n=33=9st+21t+3T,属4A核型,极其稳定,该种的三倍体类型为首次发现;(2) 二倍体类型,分布于滁州市琅琊山的野生居群,发现有2个核型,核型I,2n=22=8st+14t,属4A核型, 约占观察细胞的80％;核型Ⅱ,2n=22=1m+1sm+14st+6t,属3B核型,约占观察细胞的20％,该染色 体核型为首次报道。换锦花三倍体居群和二倍体居群的植物外部形态特征基本相同。本文还指出罗伯逊变化在石蒜属核型演化中起了关键作用。     

华南地区3种兔儿风属植物(菊科-帚菊木族)的细胞学研究

首次报道了华南地区兔儿风属(Ainsliaea DC.)(菊科-帚菊木族Asteraceae-Pertyeae)3种植物共4个居群的染色体数目和核型。其中长穗兔儿风(A.henryi Diels)的染色体数目为2n=24,核型公式为2n=16m+8sm;三脉兔儿风(A.trinervis Y.C.Tseng)的染色体数目为2n=26,核型公式为2n=16m+10sm;莲沱兔儿风(A.ramosa Hemsl.)2个居群的染色体数目均为2n=26,核型公式为2n=26=22m+4sm。所有居群的染色体由大到小逐渐变化,核型没有明显的二型性。这些结果表明兔儿风属植物确有x=12和x=13两个基数,其中x=13可能是该属的原始基数。     

3种香薷属植物染色体数目与核型分析

参照植物根尖细胞学研究的方法标准,对香薷属3种(5个居群)植物进行核形态学分析。结果表明:(1)从染色体数目看,密花香薷2居群染色体数目2n=16;野苏子2居群染色体数目2n=20,染色体数目和倍性与前人报道的一致;毛穗香薷染色体数目2n=10为首次报道。(2)聚类分析结果显示,3种(5居群)植物中野苏子和密花香薷亲缘关系较近;结合现有报道数据分析表明,该属植物仅有2种倍性(二倍体和四倍体),且二倍体占主导地位。(3)核型参数分析表明:密花香薷的稻城无名山居群1核型公式为2n=2x=16=14m+2sm,居群2为2n=2x=16=16m,着丝粒指数(CI)分别为39.57和42.32,不对称系数AI值分别为2.75和2.87,核型不对称性都为1A型;毛穗香薷的核型公式为2n=2x=10=10m,着丝粒指数(CI)为41.76,不对称系数AI值为5.25,核型不对称性为1B型;野苏子的昆明西山居群核型公式为2n=2x=20=14m+6sm,聂拉木樟木沟居群为2n=2x=20=16m+4sm,着丝粒指数(CI)分别为38.49和40.97,不对称系数AI值为4.20和4.30,核型不对称性为1B型和2B型。     

青藏高原二种车前属植物的核型和C-值报道

对青藏高原平车前(Plantago depressa)18个居群和大车前(Plantago major)2个居群的染色体数目、核型和C-值进行了研究。结果表明:西藏亚东县和林芝县的平车前居群染色体数目为2n=4x=24;其它平车前和大车前居群的染色体数目均为2n=2x=12;染色体基数均为x=6;核型类型均为1A型,核型组成和前人的研究结果不尽相同。平车前的2C-值为首次报道,随着倍性水平的增加1Cx-值降低。大车前的2C-值和前人的研究结果存在着差异。平车前和大车前不同居群的2C-值发生了变异。流式细胞仪不能用来估测车前属植物的倍性水平。     

濒危植物三棱栎四个居群的核型

报道了濒危植物三棱栎 4个居群的染色体数目和核型 ,4个居群的核型公式均为 2n =14 =10m 2sm 2st 2bs,核型类型均为 2A。间期核为复杂染色中心型 (complexchromocentertype) ,细胞有丝分裂前期染色体为中间型 (interstitialtype)。 4个居群在前期染色体中 ,可观察到2个B染色体 ,但在中期染色体中较少发现。根据核型分析结果 ,4个居群间核型变异不明显     

角堇与大花三色堇染色体核型分析

以2份角堇与4份大花三色堇自交系为试验材料,采用染色体常规压片方法,观察和分析了它们的细胞染色体数目、相对长度、平均臂比等核型指标,以明确两种植物细胞学特点,为分类以及育种提供理论依据。结果表明:(1)2份角堇自交系染色体数目均为2n=2x=26,染色体基数为x=13,染色体核型公式分别为2n=2x=26=8m+12sm+6st、2n=2x=26=4m+16sm+6st,核型不对称系数为67.20%~70.10%,核型分类均属于3B。(2)4份大花三色堇自交系均为四倍体,其中2份(EYO-1-2-1-4、DSRFY-1-1-2)染色体数目为44,核型公式为2n=4x=44=4m+16sm+6st、2n=4x=44=16m+24sm+4st;2份(G10-1-3-1-4、XXL-YB-1-1-1-1)染色体数目为48,核型公式分别为2n=4x=48=8m+20sm+20st、2n=4x=48=4m+36sm+8st,核型不对称系数为66.74%~71.77%,核型分类属于2B、3B。     

不同居群白木香的染色体研究

采用常规压片法和改良BSG法对3个居群白木香的染色体核型及Giemsa C-带带型进行研究。结果表明:3个居群白木香的核型均属2B类型,其中广西居群白木香的核型公式为2n=16=4m+8sm+4st;其他两个居群白木香的核型公式为2n=16=6m+6sm+4st,居群间核型变异不明显。白木香的C带带型为CIT型,具有着丝粒带、中间带、端带和全带。3个居群白木香C带的分布、数目和类型不完全一样,出现了带型的多态性。     

安徽石蒜属4种植物核型研究

本文分析了安徽境内石蒜属ＬｙｃｏｒｉｓＨｅｒｂ．４种植物的核型,并结合有关文献探讨它们的核型变异。结果表明,乳白石蒜Ｌ．ａｌｂｉｆｏｌｉａＫｏｉｄｚ．的核型为２ｎ＝１９＝３ｍ＋７ｓｔ＋４ｔ＋５Ｔ,属３Ｂ型;中国石蒜Ｌ．ｃｈｉｎｅｎｓｉｓＴｒａｕｂ．为２ｎ＝１６＝６ｍ＋１０Ｔ,属３Ｂ型;石蒜Ｌ．ｒａｄｉａｔａ（Ｌ’Ｈｅｒ．）Ｈｅｒｂ．为２ｎ＝２２＝４ｓｔ＋１８ｔ,属４Ａ型;换锦花Ｌ．ｓｐｒｅｎｇｅｒｉＣｏｍｅｓ．ｅｘＢａｋｅｒ．为２ｎ＝２２＝２ｓｔ＋２０ｔ,属４Ａ型。以上各种植物均未发现随体和次缢痕,通过核型比较,可见同种不同居群间在染色体数和核型结构上均存在较大的变异。     

山东10种植物的核型分析

对山东１０ 种植物进行了核型分析。茴茴蒜（ Ｒａｎｕｎｃｕｌｕｓｃｈｉｎｅｎｓｉｓ Ｂｇｅ－） 染色体数目２ｎ ＝１６ , 核型公式Ｋ（２ｎ） ＝ ２ｘ ＝ １６ ＝ ２ Ｍ ＋ ２ｍ ＋ ２ｓｍ ＋ １０ｓｔ, “３Ａ”类型; 五脉地椒（ Ｔｈｙｍｕｓｑｕｉｎｑｕｅｃｏｓｔａｔｕｓ Ｃｅｌａｋ－） 染色体数目２ｎ＝ ２６ , 核型公式Ｋ （２ｎ） ＝ ２ｘ＝ ２６ ＝ ８ Ｍ ＋ １８ｍ , “１Ａ”类型; 蛇床（ Ｃｎｉｄｉｕｍ ｍｏｎｎｉｅｒｉ（Ｌ－） Ｃｕｓｓ－） 染色体数目２ｎ＝ ２０ , 核型公式Ｋ （２ｎ） ＝ ２ｘ＝ ２０ ＝ ２Ｍ＋ １６ｍ ＋ ２ｓｍ , “２Ｂ”类型; 波斯菊（ Ｃｏｓｍｏｓ ｂｉｐｉｎｎａｔｕｓ Ｃａｖ－） 染色体数目２ｎ ＝ ２４ , 核型公式Ｋ（２ｎ） ＝ ２ｘ ＝ ２４ ＝ １６ｍ ＋ ２ｍ （ｓａｔ） ＋ ６ｓｍ , “２Ａ”类型; 白车轴草（ Ｔｒｉｆｏｌｉｕｍ ｒｅｐｅｎｓ Ｌ－） 染色体数目２ｎ＝ ３２ , 核型公式Ｋ （２ｎ） ＝ ４ｘ ＝ ３２ ＝ ３２ｍ , “１Ａ”类型; 铁苋菜（ Ａｃａｌｙｐｈａ ａｕｓｔｒａｌｉｓ Ｌ－）染色体数目２ｎ ＝ ３２ , 核型公式Ｋ （２ｎ） ＝ ２ｘ＝ ３２ ＝ ３２ｍ , “１Ｂ”类型; 地构叶（ Ｓｐｅｒａｎｓｋｉａ ｔ?     

七种药用植物的染色体研究

对山东７种药用植物的染色体进行了研究。结果表明：田旋花（ＣｏｎｖｏｌｖｕｌｕｓａｒｖｅｎｓｉｓＬ）的染色体数目为２ｎ＝７８;蜜柑草（ＰｈｙｌａｎｔｈｕｓｍａｔｓｕｍｕｒａｅＨａｖａｔａ）的染色体数目为ｎ＝８８;挂红灯（ＰｈｙｓａｌｉｓａｌｋｅｋｅｎｇｉＬｖａｒｆｒａｎｃｈｅｔｉ（Ｍａｓｔ）Ｍａｋｉｎｏ）的染色体数目为２ｎ＝２４,核型公式为Ｋ（２ｎ）＝２４＝２ｍ＋１８ｓｍ＋２ｓｔ＋２ｓｔ（ｓａｔ）,核型“２Ａ”型;无剌曼陀罗（ＤａｔｕｒａｓｔｒａｍｏｎｉｕｍＬｖａｒｉｎｅｒｍｉｓ（Ｊａｃｑ）ＳｃｈｉｎｚｅｔＴｈｅｌ）的染色体数目为２ｎ＝２４,核型公式为Ｋ（２ｎ）＝２４＝２０ｍ＋４ｓｍ,核型“１Ｂ”型;决明（ＣａｓｉａｔｏｒａＬ）的染色体数目为２ｎ＝２６,核型公式为Ｋ（２ｎ）＝２６＝２４ｍ＋２ｓｍ,核型“１Ａ”型;荔枝草（ＳａｌｖｉａｐｌｅｂｅｉａＲＢｒ）的染色体数目为２ｎ＝１６,核型公式为Ｋ（２ｎ）＝１６＝６ｍ＋１０ｓｍ,核型“２Ａ”型;车前（ＰｌａｎｔａｇｏａｓｉａｔｉｃａＬ）的染色体数目为２ｎ＝３６,核型公式为Ｋ（２ｎ）＝３６＝３２ｍ＋４ｓｍ,核型“１Ａ”型。     

A Study on Karyotypes of the Genus Lycoris

The genus Lycoris (Amaryllidaceae) consists of about 20 species, all of which are confined to temperate China, Japan and Korea. Cytological investigations, including a reexamination of the karyotypes of 14 taxa, measurements of relative nuclear DNA content, and meiotic configuration observations on some specific forms and interspecific hybrids, have been carried out by the present authors in order to re-evaluate the mode of karyotype evolution and the role of hybridization in the speciation of Lycoris. These have resulted in a new theory for explaining the karyotype evolution in the genus, which will be considered elsewhere. The present paper deals with observations on karyotypes of 11 species, 1 variety and 2 artificial hybrids. Results obtained through karyotype analysis, as shown by the data in Table 1, Plates I-VI and Figs. 1-2, reveal that: (1) the karyotypes of Lycoris rosea, L. radiata var. pumila, L. sprengeri, L. haywardii, L. caldwellii, L. squamigera and L. radiata are, on the whole, consistent with those reported by the previous authors^{[1,2,3,4,5,8,10,12]};(2) the I (rodshaped) chromosomes of L. chinensis and L. longituba are all T’s (telocentric) instead of t’s (acrocentric) or t(Sat)’s; (3) the three materials of L. aurea of different sources have shown a karyotypic differentiation: one with 2n=14=8m+6T, and the others with 2n=16=6m+10T: (4) both of the karyotypes of L. straminea and L. albiflora are 2n=19=3V+6I, inconsistent with 2n=16=6V+10I for the former and with 2n=17=5V+12I for the latter as reported by Inariyama (1953), Bose and Flory (1963) and Kurita (1987). The following aspects are worthwhile discussing: 1. The types of chromosomes. Karyotype analyses reveal the existence of three major chromosome types in Lycoris: (1) m (metacentric) chromosomes: (2) t (acrocentric) chromosomes, with short arms, (3) T (telocentric) chromosomes, sometimes with dot-like terminal centromeres. To distinghish t’s from T’s is of paramount importance for solving the problem of karyotype evolution in Lycoris. Bose (1963) pointed out that in the species with 2n=22, all I chromosomes were t’s, while in species with 2n=12-16, all I chromosomes were T’s. Our results of chromosome observations are consistent with Bose’s remarks. Some authorst^[3,6] have probably mistaken the dot-like terminal centromeres of T’s of L. longituba and L. chinensis as the short arms of t’s. 2. The significance of Robertsonian change in karyotype evolution. Although chromosome numbers and karyotypes are very variable in Lycoris, as shown in Table 1, the total number of arms of a chromosome complement of any species is always multiples of 11. Hence, it seems likely that Robertsonian changes have taken part in karyotype alteration, The genus has a series of basic chromosome numbers: 6, 7, 8 and 11. But which is the most primitive one? It is uncertain whether a successive decrease in chromosome numbers as a result of Robertsonian fusion or a gradual increase in chromosome numbers brought about by fission (fragmentation) has been the essential mechanism for karyotype evolution and speciation in Lycoris. These problems are of crucial importance and will be discussed in our subsequent papers. 3. The origin of polyploids. As evident from Table 1, there are two levels of ploidy differentiation in Lycoris: (1) di ploids with 2n=22 or the equivalent of 22, (2) triploids with 2n=33 or the equivalent of 33. The most common way of origination of triploids in plants is the hybridization of diploids with Tetraploids. But tetraploids have never been found in Lycoris. Thus, it is suggested that the triploids have originated from the combination of an unreduced gamete of a diploid with a normal gamete of another diploid. 4. The role of hybridization in speciation. Results of karyotype analyses show that hybridization has taken an important part in the speciation of Lycoris. Two types of hybrids have been found: (1) 2n=19= 3V+ 16I, L. straminea, L. albiflora and the two artificial hybrids L. sprengeri×L. chinensis and L. haywardii× L. chinensis all possess this karyotype. It could be seen from the above chromosome number and karyotype that this sort of karyotype is exactly half of the total sum of 2n=22I and 2n=16= 6V+10I. It is, therefore, quite evident that taxa possessing this karyotype are all diploid hybrids of 2n=22 and 2n=16, (2) 2n=27=6V+21I, L. caldwellii and L. squamigera possess this karyotype. It is reasonable to assume, too, that they are segmental allotriploids and have arisen from the combination of an unreduced diploid gamete of 2n=16 and a normal haploid gamete of 2n=22. The origin of the hybrid karyotype 2n=17=5V+12I reported by Inari- yama (1953) is similar to that of 2n=19, except that one of the parents possesses 2n=12= 10V+2I instead of 2n=16=6V+10I. The origin of the other hybrid karyotype 2n=30=3V+ 27I reported by Bose (1963) is similar to that of 2n=27, but the diploid gamete comes from taxa possessing 2n=22 instead of 2n=16.     

雅江点地梅（报春花科）3个居群的核型和倍性变化

首次报道了雅江点地梅（Androsace yargongensis)3个居群的染色体数目和核型,对倍性也进行研究。3个居群的染色体数目（2n),核型公式（KF）,染色体相长度组成（C．RL）,核型不对4称系数（As,K%)和核型类型（KT）分别为：野牛沟居群2n=40,KF=36m(1SAT) 2SM 2ST b,C,RL=2L 14M2 22M1 2S 2bS,As.K=54.75%,KT=2A;巴颜喀拉山居群2n=40,KF=36m 2sm 2st 1b,C.RL=4L 16M2 18M1 2S 1bS,As.K=56.31%,KT=2B;达坂山居群2n=60,KF=40m 14sm 6st,C.RL=4L 24M2 26M1 6S,As.K=59.56%,KT=2B。根据3个居群的染色体和核型不对称性与居群所在地的地理位置,认为雅江点地梅核型和倍性的演化与高海拔生态环境和寒冷、干旱的气候加剧有密切关系。     

开普芦荟和木立芦荟的染色体核型分析

对盆栽开普卢荟(Aloe ferox Miller)和木立卢荟(Aloe arborescens Miller)植物根尖细胞的染色体进行了观察分析。结果表明开普芦荟和木立芦荟的染色体数与已见报导的百合科(Liliaceae)中国芦荟(Alov vera var.chinensis)植物染色体数相同, 2n=14。染色体类型按Levan 方法分类, 没有近端部染色体和随体。开普芦荟和木立芦荟的染色体核型分析结果均为K(2n)=2x=4sm+10st。根据Stebbins 的核型分类标准, 开普芦荟的核型为"4C"型, 而木立芦荟的核型为"3C"型。两种芦荟染色体相对长度组成均为2n=14=6L+2M2+6S。根据核型研究, 可以确定百合科开普芦荟和木立芦荟的染色体基数为X=7。     

扇脉杓兰和无距虾脊兰的核型分析

为了解扇脉杓兰(Cypripedium japonicum Thunb.)和无距虾脊兰(Calanthe tsoongiana T. Tang et F. T. Wang)的核型,采用根尖压片法对扇脉杓兰和无距虾脊兰的染色体数目和核型进行了研究。结果表明,扇脉杓兰体细胞的染色体数为22,核型公式为2n=2x=22=16m+2sm+2st+2t,染色体相对长度组成为2n=22=2L+6M2+12M1+2S,核不对称系数为60.01%,核型分类为2B型;而无距虾脊兰体细胞的染色体数为40,核型公式为2n=2x=40=28m+10sm+2st,染色体相对长度组成为2n=40=8L+10M2+16M1+6S,核不对称系数为59.84%,核型分类为2B型;两者核型都较为对称。其中,无距虾脊兰的核型为首次报道。这为扇脉杓兰和无距虾脊兰的进化地位和种质保护提供了细胞学证据。     

杂交鳢(斑鳢 ♀ ×乌鳢 ♂ )及其自交后代细胞核型初步分析

对杂交鳢(斑鳢♀×乌鳢♂)(Channa maculata ♀×C.argus ♂)及其自交后代的细胞核型进行了初步分析.结果表明,杂交鳢染色体数目为2n=45,核型公式为3m+4sm+6st+32t,染色体臂数(NF)为52;杂交鳢自繁后代群体存在两种染色体核型,一是染色体数目为45,核型公式为3m+4sm+6st+...     

三裂叶豚草和普通豚草的染色体核型研究

本文对产自中国东北地区和南昌市的三裂叶豚草和普通豚草进行了染色体观察与核型分析,两种豚草的染色体数目分别为２ｎ＝２４和２ｎ＝３６,与前人的报导一致,染色体核型未见到报导。