首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1篇
  免费   0篇
  国内免费   2篇
教育   1篇
科学研究   2篇
  1984年   3篇
排序方式: 共有3条查询结果,搜索用时 109 毫秒
1
1.
一、引言 石蒜属Lycoris Herb.全世界约有20多种,其中已做过细胞染色体计数者计有17种。本文继红蓝石蒜Lycoris haywardii Traub和换锦花L.sprengeri Comes exBaker以及长简石蒜L.longituba Y.Hsu et Fan,玫瑰红石蒜L.rosea Traub etMoldenke,石蒜L.radiata(L′Her.)Herb.和矮小石蒜L.radiata var.pumila Grey(以上均待发表)之后,对安徽石蒜L.anhweiensis Y.Hsu et Fan和中国石蒜L.chinensis Traub的染色体进行计数和核型的描述和分析,旨在为今后探讨石蒜属的核型进化和种系发生提供必要的资料。  相似文献   
2.
The  present paper embodies the results of a karyotypic analysis for the species Lycoris rosea Traub et Moldenke.  The voucher specimen, J. Z. Lin 004 is pre- served in the Herbarium of Hanchow Botanical Garden. The chromosome number in root tip cells is found for the first time to be 22, and the karyotype is shown to be an asymme- trical one with rod-shaped chromosomes. A photomicrograph, the karyotype and the idiog- ram are shown in Figs. 1-2. According to Levan et aL.[5], the karyotype formula of the species is 2n=22=22t. But based on the classification presented by Bose and Flory[1], the karyotype formula should be expressed as 2n=22 =C22, and the chromosomes are all with subterminal constrictions.       If regarding 11 as the basic number and centric fusion as the major tendency of karyo- type evolution as proposed by Inariyama[2], Stebbins[6], and Jones[3,4] in particular, L. rosea would be considered as one of the most primitive species in Lycoris from point of view of karyotype evolution. Reciprocal translocations and centric fusions would give rise to V-sha- ped chromosomes. Consequently, the successive decrease in chromosome number may have taken place in the speciation of the genus under discussion. Yet further evidence seems ne-cessary for the verification of the speculation.  相似文献   
3.
A karyotypic analysis of Lycoris longituba Y. Hsu et Fan was carried out. The voucher specimen, Z. G. Mao 10501, is preserved in the Herbarium of Hangchow Botanical Garden. The chromosome number in root tip cells of the species is found for the first time to be 16, among which 6 are large, V-shaped with submedian primary constric- tions, and the other 10 are short, rod-shaped  with terminal primary constrictions. Photomi- crograph of the chromosome complement and idiogram are given in Fig. 1-3 respectively. The karyotype formula of the species is therefore 2n=16=6m+6t+4t (SAT) in the light of the chromosomal terminology defined by Levan and al.[5]      Based on the view stressed by Jones[3] and Brandham[4], successive fusion of the ch- romosomes should be taken as the essential mechanism for karyotype evolution and specia- tion in Lycoris. Reciprocal translocation, with the loss of one of the centromeres, might be the mechanism of origin for a V chromosome. It is, then, suggested that the decrease in ch- romosome number as a result of fusion of the rods with terminal or subterminal primaryconstrictions has taken place in the speciation of L. longituba.  相似文献   
1
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号