Table of Contents

10 March 2000, Volume 38 Issue 2
    Research Articles
  • WU Shi-An, Lü Hai-liang, YANG Ji, RAO Guang-Yuan, YOU Rui-Lin, GE Song
    J Syst Evol. 2000, 38(2): 97-110.
    Phylogenetic relationships in the tribe Polygonateae s. l. of Liliaceae were investigated with an RFLP analysis of two PCR-amplified chloroplast genome DNA fragments. One fragment is the transfer RNA gene for lysine( trnK gene) including the maturase-encoding gene matK, and the other is the rpl16 gene which codes for a chloroplast ribosomal protein in large subunit. The trnK gene is ca. 2600 bp in length in all the taxa, but the rpl16 gene ranges from ca. 1140 bp to ca. 1320 bp in length among different genera and in Polygonatum. The results suggested that the tribe Polygonateae s. str. consisting of Polygonatum, Disporopsis, Smilacina and Maianthemum is closely related to Convallaria in Convallarieae, and supported the earlier results that Streptopus and Disporum should be removed out from the tribe Polygonateae s. l.. The results also showed that Polygonatum formed a clad with Disporopsis, while Smilacina lumped with Maianthemum in the tribe Polygonateae s. str.. In addition, the present study supports the view that S. ginfoshanicumshould be transferred from Smilacina to Polygonatum.
  • QIU Ying-Xiong, HUANG Ai-Jun, FU Cheng-Xin
    J Syst Evol. 2000, 38(2): 111-120.
    Changium smyrnioides Wolff is an endangered species of the monotypic genus Changium (Umbelliferae). For a better understanding of its genetic diversity, four populations of this species were cytologically and allozymically investigated. The karyotypic analysis of C. smyrnioides indicated that the chromosomal number was stable (2n = 20) in all populations. Karyotypes of the populations were all “2A” type. Karyotypical polymorphism was shown as the chromosomal heterozygosity, and position shift of the satellite. Genetic diversity of 4 populations was analysed with starch gel electrophoresis. A low level of allozymic diversity was estimated based on 19 loci of 10 enzyme systems. Genetic diversity within 4 populations was relatively low with the proportion of polymorphic loci (P) ranging from 19% to 42.9%, average number of alleles per locus (A) from 1.2 to l. 7, mean expected heterozygosity ( He ) 0. 073 and mean observed heterozygosity ( Ho ) of O.030. In general, about 58% of genetic variation were attributed to the differentiation among populations, while the remaining 42% resided within populations. The genetic diversity of the eastern populations was higher than that of the southwestern populations. On the basis of this studies, we thought that the habitat of C. smyrnioides should be protected and most of the populations should be sampled soas to retain as much genetic diversity as possible in ex-situ conversation.
  • HE Zi-Can, ZHONG Yang, LIU Hong-Tao, TANG Xian-Hua, YE Li, HUANG De-Shi
    J Syst Evol. 2000, 38(2): 121-136.
    There are various arguments on classification of the genus Actinidia Lindl., a genus with approximately 63 species, 59 of which have been found in China. The paper investigated the characteristics of foliar trichomes of 35 taxa from China under optical microscope, including size, celluar structure, distribution and density. According to their micromorphological characteristics, foliar trichomes can be classified into the following six categories: 1) single-cell hairs; 2) uniseriate hairs, including linear, bulbous, twisted, straight-walled, and bent-walled hairs; 3) multiseriate hairs, including twisted, straight-walled and gradually sharpening, straight-walled and suddenly sharpening, bent-walled and gradually sharpening, and suddenly sharpening hairs; 4) multiseriate thick hairs, including pillar hairs, gradually sharpening thick hairs, and suddenly sharpening thick hairs; 5) stellate hairs, including parenchyma-stellate and sclerenchyma-stellate (normal state and special states such as rosulate, peltate-stellate, and overlopping-stellate) hairs; and 6) dichotomous hairs. On the basis of the micromorphological characteristics of foliar trichomes in Actinidia, with Clematoclethra lasioclada as an outgroup, both the quantitative cladistic analysis and phenetic analysis were performed using Wagner method and UPGMA clustering method respectively to reconstruct the phylogeny of Actinidia in China. The phylogenetic tree generated by cladistic analysis suggests that the sect. Leiocarpae be a monophyletic group, but other three sections, i.e., sect. Maculatae, sect. Strigosae and sect. Stellatae, be non-monophyletic groups. The results obtained from the phenetic analysis reflect relationships among the taxa of Actinidia in China, especially a close relationship between A. chinensis and A. deliciosa, and a relatively remote relationship between A. callosa var. henryi and A. callosa var. discolor. In conclusion, the micromorphological characters of foliar trichomes and the methods of quantitative taxonomic analysis are of key importance tostudies on phylogenetic and phenetic relationships of Actinidia.
  • XI Yi-Zhen, LANG Kai-Yong, HU Yu-Shi
    J Syst Evol. 2000, 38(2): 137-140.
    Pollen morphology of five species from China in the genus Gymnadenia R. Br. (Orchidaceae) was investigated in this work. Pollen characteristics of this genus were compared to those of its closely related genus, Neottianthe Schltr. It is found that there are some differences of pollen morphology between the two genera, e.g.: (A) Pollen massulae are mostly irregular less frequently trigonous-conical in Gymnadenia, while mainly trigenuus-conical less frequently irregular in Neottianthe; (B) Ornamentation of pollen exine surface is usually indistinct, but microperforate, microrugulate, microfoveolate or both microperforate and microfossulate in high magnification in Gymnadenia, but more distinct in Neottianthe. Exine ornamentation of this genus can be divided into five types, ( 1 ) almost smooth, or very obscurely fosset, (2) perforate, (3) fossulate or foveolate, (4) reticuloid, (5) typically reticulate. (C) the surface of pollen massulae in Gymnadenia possess viscin thread, but that in Neottianthe does not. The result of this work supports the separation ofNeottianthe from Gymnadenia as an independent genus.
  • ZHANG Zhong-Ming, CUI Ke-Ming, LI Zheng-Li
    J Syst Evol. 2000, 38(2): 141-147.
    The four-celled mature pollen of Ginkgo biloba L. just shed from the microsporangia, was round in shape and contained a very large germination area with monosulcate sulcus walled with two semicircular and nearly perpendicular parts of exine, and the pollen was coated with a compact irregular striations and spinules in parts other than the germination area. The pollen became boatshaped and was bilaterally symmetrical when it was in air or under cold storage, but rapidly rounded off in cultural solution. Studies on early morphogenesis of the male gametophyte in vitro and in vivo revealed that the tube nucleus turned a certain degree of angle, and was followed by lateral germination, while the non-active pollen maintained its round shape. The results suggest that the internal feature of the pollen tube could be a determinant factor contributing to the expression of the characteristic events of lateral germination of the male gametophyte in G. biloba. Furthermore, this biologically consistent character, together with the characteristic pollen morphology, is quite different from those of other groups in gymnosperms such as Cycas and Pinus. This might be a critical characterrelevant to the systematic position of G. biloba.
  • SA Ren, CHEN Chia-Jui, LI Pei-Chun
    J Syst Evol. 2000, 38(2): 148-166.
    The present article is the first comprehensive treatment of phytogeography of Thermopsis (Fabaceae) in the world. Thermopsis is one of the few genera within Fabaceae with the distribution pattern of the East Asia-North American disjunction. The distribution patterns of 5 recognized sections (including a new one) covering 21 species in Thermopsis are analyzed, and the results show four centres of frequency of the genus: the Eastern Asiatic Region (9 spp. / 3 sects., including 4 endemic species), the Irano-Turanian Region (7 spp./3 sects., including 3 endemic species), the Rocky Mountain Region (7 spp./2 sects., all endemic), and the Atlantic North American Region (3 spp. / 1 sect., all endemic). In the light of the fact that most species and sections, a number of phylogenetic series of the genus, and the most primitive sections and most advanced sections in Thermopsis occur in the East Asia, the Eastern Asiatic Region might be the centre of diversity of the genus. As the Irano-Turanian Region and the Rocky Mountain Region were just second to that of Eastern Asiatic Region in number of sections and species, and many polyploids appeared in these regions, they were considered as the secondary centres of distribution and speciation of the genus. The speciation looks to be frequent and complex in these regions, and many new taxa have been described from there while many new reduced or incorporated taxa have happened over there. However, recent molecular data has shown that two reduced taxa of Thermopsis are distinct in these regions. Based on the modern distribution patterns and evolutionary trends in morphological characters of the genus, and available fossil record of the genus and the historical geology, we speculate that Thermopsis had already existed on Eurasia and North America before the Late Miocene, and probably originated from an ancestral form of Sophora-like taxa with lupine alkaloids somewhere in the Laurasia in the Early Tertiary or Late Cretaceous. After the separation of the two continents, species on different continents developed distinctly under influences of different evolutionary factors. In Asia, the late Tertiary orogeny, disappearing of the Tethys and aridity and freezing caused by the Quaternary glaciation were the main forces to promote the speciation and evolutionary processes, whereas in North America it was the Quaternary glaciation and the orogeny of partial area to promote evolution of the genus. According to the evolutionary trends in Thermopsis and the distribution pattern of the primitive taxa, Sino-Japanese Subregion of Eastern Asiatic Region may be considered asthe centre of primitive forms of Thermopsis.
  • LIN Qi
    J Syst Evol. 2000, 38(2): 167-181.
    Taxonomic notes of the genus Illicium Linn. are presented based mainly on herbarium studies involving more than 10 thousand speciemens from 120 herbaria worldwide, Three new combinations are made, viz, I. fargesii Finet & Gagnep. Subsp. szechuanensis (Cheng) Q. Lin, I. parvifolium Merr. Subsp. oligandrum (Merr. & Chun)Q. Lin and I. micranhum Dunn subsp. tsangii (A. C. Smith)Q. Lin, and thirteen species, six subspecies, three varieties and two forms are reduced to synonyms. Thirty-four species, three subspecies and one variety are recognized inthis genus.
  • CHEN Sing-Chi, TSI Zhan-Huo
    J Syst Evol. 2000, 38(2): 182-184.
  • FANG Ding, WEI Yi-Gang
    J Syst Evol. 2000, 38(2): 185-188.
  • WANG Yin-Zheng, LI Heng
    J Syst Evol. 2000, 38(2): 189-191.
  • LIU Jian-Quan
    J Syst Evol. 2000, 38(2): 192-194.
  • ZHENG Wei-Lie
    J Syst Evol. 2000, 38(2): 195-197.
  • DING Bing-Yang
    J Syst Evol. 2000, 38(2): 198-200.
    This paper reports a newly naturalized aquatic genus Cabomba Aublet. (Cabombaceae) in China.