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1.
From standpoint of floristic division, Sichuan is located in the middle part
of Eastern Asiatic Region (Takhtajan 1978) or is the area where Sino-Himalayan Forest
Subkingdom and Sino-Japan Forest Subkingdom meet (wu 1979). Here exist many so-
called Arcto-Tertiary elements and newly originated species or races. In order to bring
the light the origin and differentiation of Eastern Asiatic elements, cytological investi-
gation on plants of this region are very significant. The materials of the following 5
species were collected on Mt. Emei in Sichuan Province. Voucher specimens are kept in CDBI.
1. Toricellia angulata Oliver var. intermedia (Harms) Hu
PMC meiotic examination revealed n = 12 at diakinesis (Pl. I fig. 9)
Toricellia, consisting of 2 spp., is endemic to Eastern Asiatic Region. Based on
our result along with the report of Toricellia tiliifolia (Wall.) DC. (2n=24) by Kuro-
sawa (1977), we argue that the basic chromosome number of Toricellia is 12. Many
authors, such as Airy-Shaw (1973), Dahlgren (1975, 1977), Takhtajan (1969, 1980),
Thorne (1983), have adopted Hu’s (1934) treatment erecting it as a monotypic family
Toricelliaceae. Its systematic position, whether closer to Cornaceae than to Araliaceae
or vice versa, has been in dispute. Cytologically it seems closer to Araliaceae, as shown
anatomically (Lodriguez 1971), because the basic chromosome number of Cornaceae s.
1. is x=11, 9, 8 (Kurosawa 1977), whereas that of Araliaceae is 12 (Raven 1975).
2. Cardiocrinum giganteum (Wall.) Makino
Somatic chromosome number, 2n=24 was determined from root-tip cells (Ph. I. fig.
8).
Cardiocrinum (Endl.) Lindl., consisting of 3 spp., is endemic to Eastern Asiatic
Region. C. giganteum (Wall.) Makino is distributed from Himalayan region to S. W.
China. The present report is in accord with the number reported by Kurosawa (1966)
who got the material from Darjeeling of India. However the karyotype of the present
plant is slightly different from that given by Kurosawa. In the present material, the
satellites of the 1st. pair of chromosomes and the short arms of llst. pair of chromoso-
mes are visibly longer than those of Kurosawa’s drawing (fig. 1, 2) The plants from
Yunnan, Sichuan and Hubei Provinces, named as C. giganteum var. yunnanense (Leit-
chtlin ex Elwes) Stearn, differ slightly from those of Himalayan region also in outer
morphological characters. The taxon needs both cytological and taxonomical further
studies.
3. Disporum cantoniense (Lour.) Merr.
PMC meiotic examination revealed n=8 at diakinesis (Pl. I. fig. 6)
This species is widely distributed from Himalayan region through Indo-China to
our Taiwan Province and Indonesia. Three cytotypes (2n=14, 16, 30) were reported for
the taxon including its variety, var. parviflorum (Wall) Hara, by various authors (Ha-
segawa 1932, Mehra and Pathamia 1960, Kurosawa 1966, 1971 Mehra and Sachdeva
1976a). Some authors consider D. pullum Salisb. and D. calcaratum D. Don as synonyms
of D. cantoniense. So D. cantoniense may be a species aggregate with different extreme
races. Sen (1973a, b.) reports that the somatic chromosome numbers of D. pullum
and D. calcaratum from Eastern Himalayan region are 14, 16, 28, 30, 32. He also
discovered that chromosome alterations in species of Disporum involve not only the num-
ber but the structure as well. He found that in species of Liliaceae where the reproduc-
tion is mainly vegetative, polysomaty often occurs. In China we have not only D. can-
toniense and D. calcaratum but also D. brachystomon Wang et Tang which is similar
to D. cantoniense var. parviflorum (Wall.) Hara. These taxa need further critical
studies.
4. Paris fargesii Franch.
PMC meiotic examination revealed n=5+2B (Voucher no. 112) or n=5 (Voucher
no. 62) at MI and AI (Pl. I. fig. 1. 4. 5.). This is the first report for the species. A
bridge and a fragment were also observed at AI.
Paris polyphylla Smith is extraordinarily polymorphic species. Hara (1969) re-
gards all chinese extreme forms, such as P. fargesii Franch., P. violacea Lévl., P. pube-
scens (Hand. -Mzt.) Wang et Tang, etc. as infraspecific taxa of P. polyphylla. Need-
less to say, the various races of P. polyphylla Smith in China need further critical stu-
dies and are good material for further study to understand the speciation.
5. Reineckia carnea(Andr.) Kunth
Reineckia is a monotypic genus endemic to Eastern Asiatic Region. In the present
material somatic chromosome number in root-tip cells is determined as 2n=38 (Pl. I. fig.
7). According to the terminology defined by Levan et al., the karyotype formula is
2n=28 m+10 sm. The length of chromosomes varies from 14.28 μ to 5.5 μ. The idiogram
given here (fig. 3) is nearly the same as that presented by Hsu et Li (1984). The same
number has been previously reported by several authors, Noguchi (1936), Satô (1942),
Therman (1956). The karyotype is relatively symmetrical (2B, accorling to the classi-fication of stebbins 1971) in accord with the opinion of Therman (1956). 相似文献
2.
3.
如今生活在都市里的人都渴望回归自然,希望更多地与大自然接触,但住宅建筑仅有绿色还不能说其具有生态性,住宅的生态型是以绿色为基础涵盖生态环保,可持续发展等多种理念。首先就绿色本身而言,要达到国家有关标准,并具有完整的包括设计,施工,物业管理等多个环节的生命周期评价,且要和所有城市的整体环境质量相结合。其次是垃圾处理,污冰处理的就地化,实现生态最统内部有秩序的循环转换。垃圾就地处理及时,避免了在清运中的撒泄现象和因垃圾堆放而造成的污染。 相似文献
4.
张庆长 《大科技.科学之谜》2008,(3):25-26
如果人类消失,地球上将欣欣向荣;如果蚂蚁消失,成千上万的生物将会跟着消失。20世纪初,著名的英国物理学家卢瑟福曾经骄傲地宣称:科学除了物理之外就是集邮。他的话语中显露出对科学中的博物学传统的轻蔑和不屑一顾。进入20世纪之后,各门科学的研究内容都越来越细致,从前那种"集邮"式的博物学者已经少之又少。但是,总有那么一些不合群的人,偏偏就喜欢研究那些别人不屑一顾的东西,当今的美国生物学家爱德华?威尔逊就是其中之一,他对一种小东西情有独钟。 相似文献
5.
6.
2008年第29届奥林匹克运动会将在我国首都北京举行,这将会对我国的体育事业产生强大的推动力.我国教练员、运动员职业道德水平的高低将直接影响举办奥运会的质量.因此,我们要加强对教练员、运动员职业道德的培养,以奥运的目标管理他们,在奥运会的赛场上展现出我们最为优秀的一面. 相似文献
7.
现在竞争激烈的社会需要的是综合性人才,本文从如何从工作生活中学习,如何提高面试成绩,如何面对应聘失败,如何做好工作,如何做一名优秀的员工等这几个方面进行详细的阐述。 相似文献
8.
了解各种遗传病的类型,掌握AD、AR、XD、XR、MF等各种遗传病的特点,初步学会看遗传系谱图.根据各种遗传系谱图的特点,结合实际来解决现实生活中的各种遗传问题,同时可用来阐明国家提倡优生优育的原因,解释《婚姻法》规定禁止近亲结婚的理由. 相似文献
9.
10.
谢智伟 《大科技.科学之谜》2008,(3):6-10
脚蹬"拖鞋式冰鞋",身穿"鲨鱼皮泳衣",头戴"蝙蝠侠面具",最好再配上一辆最新型场地自行车……如今的奥运会,俨然成了"新式武器"大显身手的舞台。当我们为现代科学促进奥运发展而欢呼的时候,是否也要看到科技在奥林匹克运动上所展现的另一面? 相似文献
11.
秦岭地区10种百合科植物核型报道 总被引:1,自引:0,他引:1
本文对秦岭地区的Polygonatum的2种,Hosta的2种和Smilax discotis,Cardiocrinum
giganteum,Asparagus filicintus,Reineckia carnea,Tupistra chinensis,Rohdea japonica做了核型分析。其中有4种的核型为国内首次报道。本义对不同产地的玉竹gonatum odoratum)的核型进行了对比,讨论了其核型进化的可能途径。 相似文献
12.
In the work mitotic chromosomes in root-tips of 7 species native to Sichuan Pro-
vince were examined and their karyotypes were analysed based on 7-8 cells at mitotic meta-
phase, using Levan et al.'s (1964) nomenclature. The list of species and origin of the materials
used in this work are provided in the appendix. The micrographs of mitotic metaphase of all
the materials are shown in Plates 1 and 2; the idiograms in Fig. 1, 1-9, and the parameters
of chromosomes are provided in Tables 1-9. All the chromosome countings and karyotypes in
this paper are reported for the first time.
Characteristics of the karyotypes may be summarized as follows:
1. 2n=38 are found in all the materials except A. sichuanensis, which has 3 cytotypes, i.e,
2n=38+5B, 2n=38+lB and 2n=38+OB (Plate 2, 1-2, Fig. 1, 5-6).
2. The karyotypes are of two major types: the karyotype of A. flaviflora falls into 3C in
Stebbins's (1958, 197l) classification of karyotypes and those of all the other species into 2C.
The two types are also different from each other in the number of large and medium-sized
chromosomes pairs and morphology of the first pair of chromosomes (compare Plate 2, 5, Fig.
1, 9 with the other micrographs and idiograms).A. flaviflora with the karyotype 3C also differs
from the other species in a series of gross morphological characters: the species is of a yellow and
campanulate corolla.
3. The species with caespitose leaves (A. caespitosa and A. omeiensis) have essentially the
same karyotype, which is rather different from those of the species with scattered leaves. There
are two pairs of small sm chromosomes (arm ratio ≥1.90) in the former karyotype (Tables 1
and 3), but all the small chromosomes are m or sm with arm ratio <1.80 in the latter karyotypes. 相似文献
13.
本文对睡莲科6属6种代表植物的核型进行了研究,并探讨了它的分类学位置。结果如下:莲2n=16=9sm+4m+3st;王莲2n=24=8sm+8m+8T,蓝睡莲2n=28,可配成14对,染色体小,第l号染色体上有2条随体;萍蓬草2n=34=18m+16sm;芡实2n=58,可配成29对,染色体小,第l号染色体有2条随体,莼菜2n=72,可配成36对,染色体按大小可分成大,中、小三个类别。除莲外,其它5种植物的核型为首次报道。莼菜的体细胞染色体数目2n=72和国外报道的2n=80不相一致。莲的染色体以及形态学特征和其它睡莲科分类群显著不同,可将其从睡莲科中独立出来,并成立莲科和莲目。原归属于睡莲科的分类群仍组成睡莲目,并分别置于莼菜科和睡莲科。 相似文献
14.
A karyotypical analysis of Anemarrhena asphodeloides Bung. of the monotypic genus
Anemarrhena Bung. (Liliaceae) was carried out for the first time. The number of chromo-
somes in root-tip cell of the species was found to be 22, agreeing with that reported by Sato[12], although inconsistent in some other respects, such as position of centromeres, length of chromosomes, and nucleoli, etc. (Table 1 ). According to the terminology defined by Levan et al.[8], the karyotype formula is therefore 2n=22=2sm (SAT)+2sm+18m.
Photomicrographs of the chromosome complements and idiogram of the karyotype are given
Fig. 1 and 2).
The karyotype of Anemarrhena asphodeloides shows explicitly to be asymmetrical, with three pairs of long chromosomes and eight pairs of short chromosomes. This specialized feature, when considered together with the rare occurrence of the basic chromosome number of 11 of the genus within the Tribe Asphodeleae of Liliaceae (see Table 1), suggests that the genus Anemarrhena is probably a rather specialized one, which has scarcely any intimate relationship with the other genera of the above tribe. The fact that this specialized karyotype is associated with certain trends of morphological specialization, such as flowers possessing three stamens only, gives support to the above suggestion. But, it is impossible to draw a more precise conclusion without a more thorough and comprehensive investigation of the species in question. 相似文献
15.
李林初 《中国科学院研究生院学报》1993,31(5):405-412
本文分析了我国特产树种红杉Larix potaninii的核型,K(2n)=24=12m+8sm+4st,属2A类型,染色体相对长度组成为2n=24=4L+8M2+8M1+4S。落叶松属植物(10种)的核型由6对较长的中部着丝粒染色体和6对较短的、臂比大于2的近中或近端着丝粒染色体构成,这是较为进化的核型,其中红杉组Sect.Multiserales则似有比落叶松组Sect.Larix更进化的趋势。根据松科各属核型的比较,作者发现落叶松属和黄杉属非常近缘而与其他属较为疏远,因此由它们组成落叶松亚科可能较为合适,这是一个较进化的亚科。该结沦也得到形态学、解剖学、孢粉学、生物化学及古植物学等方面资料的支持。 相似文献
16.
本文对江西、浙江、四川的万年青Rohdea japonica,开口箭Tupistra chinensis、筒花开口箭
T.delavayi、金山开口箭T.jinshanensis以及弯蕊开口箭T.wattii的核型进行了分析,其中筒花开
口箭、金山开口箭和弯蕊开口箭的核型为首次报道。万年青属的基本核型为2n=38=26m十10sm十
2st;开口箭属的基本核型为2n=38=26m+12sm,两者极为相似。本文还对万年青属、开口箭属
与其邻近属——铃兰属Convallaria、吉祥草属Reineckia、白穗花属Speitantha,蜘蛛抱蛋属Aspi-
distra等的核型进行了分析讨论。 相似文献
17.
本文报道了我国特有植物白穗花(Speirantha gardenii(Hook.)Baill.,百合
科)的体细胞染色体数目,并进行了染色体核型分析。取材于安徽黄山的白穗花
为一个二倍体物种,它的体细胞染色体2n=38=22m+6sm+10st。其中第
9对染色体为亚中部着丝点染色体,在短臂的近着丝点处具一次缢痕,是19对 染色体中唯一的一对随体染色体。 相似文献
18.
李林初 《中国科学院研究生院学报》1986,24(5):376-381
本文首次报道秃杉的核型为K(2n)=22=16m+6sm, 3号染色体具“长着丝点区 域”。似具比同属的台湾杉(18m+4sm)进化的趋势。它们均为"2B"。从国产杉科植物的 核型类型看,似见"2B"的台湾杉属与"1B"的杉木属和"1A"的水杉属、水松属、柳杉属的亲缘关系依序由近到远并比它们进化。本作者还观察了秃杉的核仁数目和多微核现象。 相似文献
19.
本文对浙江产的Disporum sessile, Tricyrtis macropodo, Scilla rcilloides,Ophiopogon japoni-
cus,Liriope platyphylla和Allium macrostemon的核型作了分析,并报道了Polygonatum odoratum
和Asparagus cochinchinensis 的单倍体染色体数目。其中绝大多数为国产材料的首次记载。 相似文献
20.
本文对陕西、四川和河北的Paris 2种,Cardiocrinum giganteum, Smilacina 2种,Allium
2种, Asparagus 2种,以及Convallaria majalis 的核型作了分析,其中Paris polyphylla var.
latifolia, Smilacina henryi 和 Allium ovalifolium 的染色体报道为第一次。 首次发现Perisverticillata 中四倍体细胞宗的存在。本文对Paris的核型、地理分布和分类作了分析讨论。 相似文献