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1997, Vol.35, No.2 Previous Issue    Next Issue
Phylogeny of the Pinaceae Evidenced By Molecular Biology
Wang Xiao-quan, Han Ying, Deng Zheng-rong, Hong De-yuan
1997, 35 (2): 97-106. 
Abstract ( 0 )
The molecular phylogeny of the Pinaceae represented by nine species of eight genera was investigated through PCR-RFLP analysis of a cpDNA fragment,  which was approximately 2550 bp long and homologous with the DNA fragment from the upstream of rbcL to part of accD in cpDNA of Pinus thunbergii.  Identified by 18 restriction endonucleases were 86 recognition sites, of which 54 were polymorphic. The restriction site data were analyzed with PAUP (version 3.1.1 ) and Mega (version 1.01). As a result, the most parsimonious Wagner tree constructed by branch-and-bound search is similar to the neighbor-joining tree in topology.  Cathaya,  Pinus,  Larix and Pseudotsuga  form a monophyletic group, and Larix is closely related to Pseudotsuga. Cathaya is more closely related to Pinus  than to Pseudotsuga  and Larix,  but the close relationship between Cathaya and Pinus is not well supported by the bootstrap test. Abies has a close relationship to Keteleeria.  Moreover, the system proposed by Zheng and Fu (1978) that the family Pinaceae was divided into three subfamilies, i.e., Abietoideae, Laricoideae and Pinoideae, is artificial, because the former two are not monophyletic.
The Discovery of Tetraploid Camellia reticulata and Its Implication in Studies on the Origin of This Species
Gu Zhi-jian
1997, 35 (2): 107-116. 
Abstract ( 0 )
Camellia reticulata and its two allied species, C. saluenensis and C. pitardii,all from the Jinshajiang Valley of Yunnan and Sichuan, were cytologically studied in this work. Among 34 populations of C.reticulata studied here, 21 were found to be tetraploids (2n=60), 11 hexaploids (2n = 90), and the remaining two diploids (2n = 30). Tetraploid was reported in C. reticulata for the first time and its karyomophology was studied. In meiosis of pollen mother cells of the tetraploids and the hexaploids, only bivalents were observed in most of the populations, although in several populations or individuals a few univalents or tetravalents appeared. In the hexaploids, hexavalents were not observed. Thus, the meiotic chromosome cofigurations showed that the tetraploids and hexaploids in C.reticulata allopolyploids, and the appearance of a few tetravalents in some populations might indicate
homology of chromosomes in different genomes to some extent. The characteristics of the resting nuclei and the prophase chromosomes of all the tetraploids and hexaploids were quite similar to each other. The tetraploids of C.reticulata from the localities with the altitude of over 1800 m were gross-morphologically similar to the hexaploids, but those growing between 1100 ~1800 m were different to some extent from the hexaploids. In geographical distribution, the tetraploids and the hexaploids were continuous, and overlapped with C. saluenensis and C. pitardii.
Pollen Morphology in the Subtribe Aspidistrinae (Liliaceae s. l.)
Huang Jin-ling, Hong De-yuan
1997, 35 (2): 117-124. 
Abstract ( 0 )
Pollen morphology in the subtribe Aspidistrinae is reported and the main viewpoints are summarized as follows: (1) Two major types of pollen grains, i.e., monosulcate,ellipsoidal pollen and inaperturate, spheroidal pollen, are identified in the genus Tupistra. The species with monosulcate, ellipsoidal pollen usually have monomodal karyotypes, brightcolored flower, smaller stigma, and stamens inserted at upper or middle part of perianth tube, while the inaperturate and spheroidal pollen is always found in the species with bimodal karyotypes, dingy-colored flower, swollen stigma and stamens inserted at the base of perianth tube. (2) Pollen grains in the genus Rhodea are monosulcate and ellipsoidal, while those in the genus Aspidistra are inaperturate and spheroidal, correspondingly similar to the second type of pollen grains in the genus Tupistra. (3) The most primitive pollen in the subtribe Aspidistinae is regarded as monosulcate and ellipsoidal, having perforate or reticulate exine sculpture. The inaperturate, spheroidal pollen with verrucate, gemmate or rugulate exine sculpture is considered derived; (4) Unlike those reported in other groups of the family Liliaceae, the infraspecific pollen shape, aperture type and exine sculpture in Aspidistrinae are basically stable and may serve as a taxonomic character.
Pollen Morphology of Trichosanthes and Its Taxonomic Significance
Huang Lu-qi, Yang Bin, Yue Chong-xi, Cheng Chung-yung
1997, 35 (2): 125-135. 
Abstract ( 0 )
The pollen grains of 31 species and 1 variety of the genus Trichosanthes were examined under light microscope and scanning electron microscope. All of them are 3 (4)-colporate. The exine ornamentation can be divided into four types, which can be used for the identification of individual section and species. This division is consistent with the taxonomy based on gross morphology, i.e. verrucate or rugulate (Sect. Trichosanthes), coarsely reticulate (Sect. Bracteatae), reticulate or smooth (Sect. Folibracteola), rugulate or nearly smooth  (Sect.  Cucumeroides).  The  colporate  character  supports  to  divide  Sect. Foliobracteolia into two subsection,  Subsect.  Foliobracteolia (with distinct colpi ) and Subsect. Villosae.
The Geographic Distribution of the Genus Caragana in Qinghai-Xizang Plateau and Himalayas
Zhang Ming-li
1997, 35 (2): 136-147. 
Abstract ( 0 )
The Qinghai-Xizang(Tibet) Plateau and the Himalayas, a well-known natural region, is a diversity center and the southern distribution limit of the genus Caragana Fabr.,which is of typical temperate asian areal type. There are twenty-four species and one variety of Caragana recognized by the author in this region, accounting for one-third of total species of the genus. According to the phylogenetic scheme of the genus(Moore, 1968), taxa occurring in this region are all advanced. They consist of not only the rachis-persistent group but also palmate-foliate group. This fact indicates that the differentiation of Caragana is active in this region. The endemism is common, in Caragana most of species are endemic. The vicarism is mainly influenced by some ecological factors such as climate and vegetation . Ser. Bracteolatae Kom. , including five species, forms a vicarism example along the Hengduan
Mountains and Himalayas. The strong adaptation ability of species makes them become some dominant or prominant groups within their shrub communities. The cold and arid adaptations are illustrated by a series of species appearing in forest, grassland and desert as well as the related morphological variation.  The areal relationships within the Qinghai-Xizang Plateau and Himalayas were analyzed by using MST (Minimum Spanning Tree) and PAE (Parsimony Analysis of Endemism). The floristic regionalizations of Wu(1979) for China and Mani(1978) for the Himalayas were consulted. The results indicate that the Hengduan Mountains especially its northern part, is a geographic node, from there the species of Caragana adaptively radiate northwards to Tangut and eastwards to southeastern Xizang. The Hengduan Mountain has little relation to the western Himalayas. There is no widespread species of Caragana across many different vegetation zones. The dispersion in Caragana is short in distance and the isolation results from different ecological factors. Although the Qinghai-Xizang Plateau and Himalayas is probably not the place of origin of the genus, the adaptive radiation trend in China might be from Northeast to Southwest according to the relationships between this region and the adjancant regions. In addition, based on the restricted distribution pattern of the genus, together with the fossil records of other genera of the subfamily Papilionoideae, it could be considered that Caragana originated at eastern Siberia in the Late Miocene to Pliocene of the Tertiary.
A Taxonomical Study on the Genus Roegneria C. Koch from China
Cai Lian-bing
1997, 35 (2): 148-177. 
Abstract ( 0 )
In this paper, the large genus Roegneria (Poaceae) from China is revised on the basis of “F1. Reip. Pop. Sin. (FRPS)”, Vol. 9(3). As a result, 19 new combinations or statuses are proposed. By dividing sections with the differentiating of glume, and series with that of awn, a total of 4 sections, 18 series, 79 species and 22 varieties are recognized in China, of which 7 series, 5 species and 1 variety are described as new.
The Consideration of Archineottia as Congeneric With Holopogon (Orchidaceae)
Chen Sing-chi
1997, 35 (2): 178-180. 
Abstract ( 0 )
The genus Archineottia is transferred to Holopogon based on column structure,
and accordingly five new combinations are made: Holopogon gaudissartii (Hand.-Mzt. ) S.
C. Chen, H. microglottis (Duthie) S. C. Chen, H. pantlingii (W. W. Smith) S. C.
Chen, H. smithianus (Schltr.) S. C. Chen and H. japonicus (M. Furuse) S. C. Chen.
A New Species of Ligularia from Sichuan, China
Chen Guang-huo, Zhang Wen-jin
1997, 35 (2): 181-182. 
Abstract ( 0 )
A New Species of Prasiola from Yunnan, China
Wang Ruo-nan, Qian Cheng-yu
1997, 35 (2): 190-191. 
Abstract ( 0 )