Abstract:This paper deals with the Hainan endemic species and genera and their distribution. There are 19 China endemic genera of flowering plants in the island, 8 of which are endemic to Hainan, viz. Pyrenocarpa, Chunia, Setiacis, Parapyrenaria, Wenchengia,Metapetrocosmea, Pentastelma and Cathayanthe. The seed plants of this island amount to 3315 species, of which 1110 species are endearic to China and 505 species or 15.23% of the total species being endemic to Hainan. Most of them occur at altitudes of 300─1400m and some species appear only in limestone area. The flora of Hainan indicates closer relationships to that of Guangdong, Guangxi and Yunnan than to that of E. China and C.China. Many China endemic species in Hainan are in common with those in Guangdong,Guangxi and Yunnan, but not in E. China and C. China. Some species, such as Casearia aequilaterais, Homalium paniculiflorum, Ardisia humilis, Diospyros strigosa, Pseuderanthemum haikangense, Munronia heterotricha and Artabotrys pilosua, occur only in Hainan and S.Guangdong. Those, such as Horsfieldia hainanensis, Munronia hainanensis, Cnesmone anisosepala, Goniothalamus chinensis, Hainania trichosperma, Oncodostigma hainanense, Firmiana pulcherrima and Aristolochia hainanensis are found only in Hainan and S. Guangxi, while Goniothalamus howii, Ziziphus fungii, Begonia anaustinei, angustinei, Schefflera Hainanensis and Symplocos lancilimba only recorded from Hainan and S. Yunnan. Such distribution patterns may beascribed to the relatively identical climate and geological history of Hainan, Guangdong,Ouangxi and Yunnan.

Abstract:Sapindaceae is a pantropical distribution family.It is widely distributed in the world except Europe.The Radlkofer's(1931─1934) and J.Muller & P.W. Leenhouts'systems were discussed.The later one was adopted by the present authors. Based on the analysis of generic distribution, the floristics of the family was studied. According to the Takhtajan's (1986) world floristic classification system, Indomalesian subkingdom is the richest region of Sapindaceous plants in the world, the second is Africa, and the third,Neotropic. But the most primitive tribe, Dodonaeae is limited to Australia except one genus endemic to New Caledonia and some pantropical species of Dodonaea.There are only 25 genera and 54 species of sapindaceous plants in China,amouting to 17% and 3% of them in the world, respectively. Among the 25 genera, 6 of them are endemic ones.Most of them are located in the northern edge of generic distribution except the endemic genera(Eurycorymbus, Delavaya. Handeliodendron, Xanthoceras) and Koelreuteria,Boniodendron and Pavieasia. Most of the sapindaceous plants in China are shared with Indo -Malaysia, especially Vietnam.Based on the evidence of microfossils and modern distribution pattern of the family, it can be concluded that the family was possibly originated on Gondwana in very early Cretaceous, and its dispersal pathway is schematized.

Abstract:Two new species and a new variety are described from Xiaojin River, Boluo,Guangdong. They are Ormosia boluoensis Y. Q. Wang et P. Y. Chen, Ilex xiaojinensis Y.Q. Wang et P. Y. Chen and Rosa laevigata Michx. var.leiocarpus Y. Q. Wang et P. Y.Chen.

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Abstract:Using Teyleria and Glycine as outgoups, 11 equally most parsimonious cladograms of Pueraria are yielded from cladistic analysis based on twenty-four morphological characters. The motley assemblage named by Lackey is a group of cladistically most primitive species. The authors indicate that the species in subsections Pulcherrima and Pueraria of section Pueraria discribed by van der Maesen form a monophyly, and subsedion Nonnundiflorae (Section Pueraria)excluding P. imbricata, P.bella and P. alopecuroides, is another monophyly. The sectional status of P.phaseoloides is not warranted. Revisions of the classification of the genus are suggested.

Abstract:Cells of Stevia rebaudiana callus tissue contain chloroplasts when cultured in a liquid medium in the light. Transfer of the callus into the fresh culture medium results in the gradual decrease or disappearance of photosynthetic lamellae and the eventual dedifferentiation of chloroplasts to form proplastid-like structures. This decrease or disappearance of photosynthetic lamellae is found to be correlated with the degradation of internal membranes, coupled With the diluting out of stroma constituents and thylakoid membranes due to chloroplast divisions, especially unequal constriction. The process is not completely synchronized so that some plastids still retain a few intact lamellae while other plastids contain degenerating lamellae or have lost the lamellae completely. In addition, some plastids observed at this stage contain one to several starch grains although starch is very rarely found in the inocula. A stricking feature at this stage is the apparent grouping of organells in the vicinity of the nudeus. The cytoplasm has increared in quantity and crosses the cell in bridge-like extensions partially filling in the cell center. At this stage, well defined proplastids are recognized. After 7 days of continuous culture, many Cells appear meristematic in that the cytoplasm, rich in organelles, fills most of the cell. The majority of the plastids found in the cell at this stage are proplastids. They may be ptesent as budded dividing forms or as oval spheroids. Their internal structure consists of randomly positioned single thylakoids resembling those of proplastids in intact development leaves. During the stationary phase of cell growth, the internal membranes of plastids are organized into stacked grana interconnected by stroma thylakoids, and at the same time the plastid ribosomes increase. A correlation was discussed between the dedifferentiation of the highly vacuolate cells induced by the subculturing process and a dedifferentiation of the chloroplasts with the cells.

Abstract:The morphological character, meiosis and karyotype of Guangdong plantain were studied. According to taxonomic scoring of the 15 diagnostic characters, the highly homologous genomes and the autotriploidy karyotype, Guangdong plantain is more desirably dassified in BBB group and its scientific name should be Musa balbisiana Colla (BBB group).

Abstract:Female gametophyte development and the early embryogenesis in Cymbidium sinense were observed. The ovule is anatropous with 2 integuments and one layered nucellus around the megaspore mother cell. The mature embryo sac consists of 8nuclei and conforms to the Allium type. The interval between pollination and fertilization is about 100 days and the normal double fertilization has been observed. Primary endosperm cell divides and forms 2─6 nucleus endosperm. During the development of the embryo, a suspensor consisting of a row of 5─6 cells is formed. It takes about 8 months from the pollination to the maturation of the seed. The embryo in the mature seed is just a globular mass of 110─120 cells without diffelentiation. The endosperm nucleus and suspensor are all degenerated in the mature seed.

Abstract:Pepino (Solanum muricatum Ait.)seedlings were treated at 5─35℃ in growth chamber at light intensity of 100 umol m-2s-1. The young fully expanded leaves were excised after 3 days of treatment for a comparison of the temperature response of several phsiological characteristics.Higer photosynthetic rates appeared at temperature ranging from 15℃ to 30℃-.Photosynthetic rates was found at 20℃ which was associated with the highest rate of photosynthetic electron transport, photochemical efficiency of PS Ⅱ and quantum yield of PS Ⅱ electron transport, and it is also the case for chlorophyll content, but with the lowest permeability of cell membrane. These physiological parameters were obviously decreased at low temperature 5─10℃ and high temperature 35℃. The extent of the decrease was increased with prologation of treated time. The electrolyte leakage of cell membrane of leaves was reduced after eliminating from 5℃ treatment and transfering toroom temperature (15─20℃).

Abstract:A procedure for isolation,culture and plantlet regeneration from mesophyll protoplasts of Solanum quitoense Lain.was reported. Young leaf protoplasts from aseptic plants grown in controlled environment were plated at 1×104 protoplasts ml-1 on modified K8p medium with 2,4-D 0.5mg L-1+NAA 1mg L-1+BA 0.5mg L-1. Protoplast division was initiated after 3 days, and one week later the 3rd and 4th divisions were observed. After culture for four weeks the protoplast-derived calli grow to a size of 1─ mm in diameter, and the planting effeciency (PE) amounted to 0.1─0.2%. Protoplast-derived calli were transferred onto MS+2,4-D 0.5mg L-1 for proliferation. One month later the calli were transferred again onto MS+IAA+BA (or ZT). Subsequently, shoots occured at 42.9% effeciency on MS+IAA 1mg L-1 +ZT 5.0mg L-1. Shoots were rooted on MS +IAA 0.2mg L-1 successfully.