Table of Contents

10 May 1995, Volume 33 Issue 3
  
    Research Articles
  • Deng Yan-bin, Hu Zheng-hai
    J Syst Evol. 1995, 33(3): 209-220.
    The outer morphology and micromorphology as well as the structure of nectaries of 74 species and 1 variety,belonging to 9 tribes and 36 genera of Cruciferae,were examined by light microscope (LM) and scanning electron microscope (SEM) to reveal the morphological structure and the evolutionary trends of floral nectaries.The floral nectaries of Cruciferae were an outgrowth of receptacle.The anatomical features of floral nectaries showed that the internal structure was comparatively consistent.They were composed of the epidermis and nectariferous tissue which has vascular bundles(some species were absent). The modified stomata were present in the epidermal layer and were thought to have a passage in the nectar secretion.However,in a small number of species,there was a structure of small pores in the epidermis;The special-shaped cells which were found to contain polysaccharide and the large parenchyma cells were also observed in the nectariferous tissues.However,the outer morphology of floral nectaries showed greater diversity in number,shape, cuticle sculpture,composition,position and in existence of vascular bundles.These characteristics were different among genera of the same tribe,and sometimes were also different in different species of the same genus.So,they may be of some significance for taxonomy. The floral nectaries of Cruciferae can be divided into three types according to their distribution,morphology and structure:1.Lateral-nectary type:the nectaries were only composed of lateral nectaries;2.Lateral and median nectaries type: the nectaries were composed of lateral and median nectaries,which were separated; 3.Annular-nectary type:lateral and median nectaries united into annular one.The division diviates from the view that was proposed separately by Norris and Clemente and Hernandez. Furthermore, 19 sub-types were divided under the three types. The lateral and median nectary types were considered as primitive whereas the lateral-type and the annular-nectary type were advanced. The evolutionary trends of floral nectaries of Cruciferae are as follows: degeneration of Lateral and Lateral nectary type Median-nectaries→ median nectary
    type the combination of Annular nectary type
    lateral and median nectarines The possible relationships among the tribes were also discussed according to the distribution of types and sub-types of nectaries in different tribes of Cruciferae.
  • Tian Hui-qiao, Chen Jia-kuan, Guo You-hao
    J Syst Evol. 1995, 33(3): 221-224.
    Ranalisma rostratum Stapf is a rare and endangered species. This paper deals with the development of its male and female gametophytes and probes the relationship between the process of reproduction and the cause which made this species endangered. The meiosis of microspore mother cells is successive cytokinesis and the microspore tetrads are isobilateral. Pollen grains are 3-celled when shed. The ovule is anatropous,bitegmic and tenuinucellate. The micropylar dyad cell usually desenerates soon after its formation, and the chalazal dyad cell develops into a Allium type embryo sac. During the development of embryo sac both polar nuclei are respectively located at the two ends of central cell,and they maintain this situation until the micropylar polar nucleus takes part in fertilization. Features of the embryo sac of Ranalisma rostratum Stapf are discussed.
  • Yang Qin-er, Gu Zhi-jian, Sun Hang
    J Syst Evol. 1995, 33(3): 225-229.
    Investigated in this work was karyomorphology of Beesia deltophylla.The resting nuclei and prophase chromosomes were categorized as complex chromocenter type and interstitial type respectively.The metaphase chromosomes were counted to be 2n=16.The karyotype was formulated as 2n=10m+4st+2t(2sat).Based on the results,the karyotypic difference between B.calthifolia and B.deltophylla was shown,and the systematic position of the genus Beesia was discussed.Beesia might be closely related to Cimicifuga and its allied genera,but only distantly related to Trollius and its allies,and thus it might be more reasonable to place Beesia in the tribe Cimicifugeae than in the tribe Trollieae.
  • Liang Song-yun
    J Syst Evol. 1995, 33(3): 229-229.
  • Liao Liang, Xu Ling-ling, Chen Ye, Fang Liang
    J Syst Evol. 1995, 33(3): 230-239.
    Ranunculus cantoniensis DC. polyploid complex was proposed by Okada. In order to clarify the structure of the ployploid complex,it is necessary to carry out a karyotype study on the complex and its allied species from China,where is the main distribution region of the complex.The karyotype analysis followed Li et al.The ployploid chromosomes in the complex were arranged according to the length of chromosomes and the position of centromere.The experimental materials are listed and the vouchers are deposited in JJT and PE.The experimental results and essential points are as follow:Ranunculus trigonus Hand.- Mazz.was found to have two cytotypes,which are correlated with the plant height.The short plant population has the karyorype 2n=2x=16=4m+6sm+6st(2SAT),while the high plant one has the karyotype 2n=2x=16=4m+2sm+10st (2SAT).The two karyotypes are first reported. Ranunculus silerifolius Lévl.was reduced to asynonym of Ranunculus cantoniensis DC.by L.Liou in 《F1.Reip.Pop.Sin》Vol.28.According to the characteristic of their chromosomes and morphology of experimental materials in the study,we suggest that the Ranunculus silerifolus Lévl. be treated as an independent species.The karyotype (2n=2x=16=6m+2sm+8st) of Ranunculus chinensis Bunge,from Beijing,are almost entirely similar to that from Japan except that satellites are not found.The karyotype of Ranunculus silerifolius Lévl.(2n=2x=16=6m+2sm+6st+2t) in Guizhou Province of China is similar to the Mastuyama-type or Mugi-type of Ranunculus silerifolius in Japan.The karyotype(2n=4x=32=4m(a)+2m(b)+2sm(b)+4t(SAT)(c)+4st(d)+2m(e)+2sm(e)+2sm(f)+2st(f)+4st(g)+2st(h)+2m(h)) of Ranunculus cantoniensis DC.from Jiangxi Province of China is similar to the Kushikino-type in Japan. It consists of two different genomes. One of them is similar to the that of Ranunculus silerifolius (2x) or Ranunculus chinensis (2x) reported in the paper. The other is the genome named “short m –type”, which must have a pair of satellite chromosomes, No. 11 or No. 12, and a pair of “short m-type” chromosomes, No.16.The karyotype (2n=5x=40=3m(a)+2sm(a)+2st (b)+3sm(b)+2t(c)+3t(SAT)(c)+5st(d)+sm(e)+5sm(f)+5st(g)+5m(h)), of Ranunculus vaginatus Hand. -mazz. which is first reported, is basically similar to that of Ranunculus siebodii Miq. (2n= 6x= 48= 6m(a) +2st (b) +4sm(b)+4t (SAT) (c) +2st (SAT)(c)+6st(d)+6m(e)+6sm(f)+6st(g)+6m(h)) except ploid level and the morphology of two taxa is also similar to each other. They consist of two or three different “short m-type”chromosome sets respectively. We think that Ranunculus vaginatus has probably originatedfrom the hybridization between R. sieboldii (6x) and an unknown allied tetraploid. It is probable that the members in the complex and its allied species became related through the genome called “short m-type” (Plate 2) and thus a polyploid pillar complex formed.
  • Qin Hai-ning
    J Syst Evol. 1995, 33(3): 240-243.
    The monotypic genus Archakebia from China is described as new.The genus shares many characters with members of the genus Akebia,except sepals 6,lanceolate or linear,which are common in members of the genus Stauntonia.
  • Yang Han-bi
    J Syst Evol. 1995, 33(3): 244-250.
  • Wu Cheng-yhi, Ku Tsue-chih
    J Syst Evol. 1995, 33(3): 251-280.
  • Tsi Zhan-huo, Chen Sing-chi
    J Syst Evol. 1995, 33(3): 281-296.
    Xishuangbanna, lying between 99°56´ and 101°50´E longitude and 21°08´ and 22°36´ N latitude of southern Yunnan, is located on the northern fringe of the tropics. Its orchid flora is very rich but little known to the outside world. From 1980 to 1992, the authors tripped seven times to that region collecting and studying orchids there. As a result, 335 species and two varieties belonging to 96 genera were identified as indigenous to Xishuangbanna region. Among them, two genera (Pennilabium J. J. Sm. & Parapteroceras Averyanov), 50 species are new to China, 190 species new to this region, and 21 species and one variety are endemic to Xishuangbanna. It is interesting to note that both genera and species native to Xishuangbanna are more than those in Hainan and comparable to those in Taiwan, though the collection in this region is not complete.
  • Wang Ying-zheng
    J Syst Evol. 1995, 33(3): 297-301.
  • Peng Ze-xiang, Zhang Bing-yan
    J Syst Evol. 1995, 33(3): 302-305.
  • Huang Rong-fu
    J Syst Evol. 1995, 33(3): 306-307.
  • Zhang Li-bing, Kung Hsian-shiu
    J Syst Evol. 1995, 33(3): 308-312.