| Malania oleifera was discovered in 1970s and was a peculiar single-species andsingle-category plant in China. Malania oleifera only distributed naturally in thewest of Guangxi Zhuang National Autonomous Region and the southeast of Yunnanprovince. The seeds were rich in oil fat and were the ideal raw materials of musconesynthesizes, so it had substantial development value. At present the resources wasscarce, so it was listed as the national second level of protections plants.This paper tried to find the endangering causes and development values ofMalania oleifera through studying the relationship between geographical distributionand environmental factors, site conditions, anatomical characters, community andpopulation characters, genetic diversity of populations, pollination mechanism ofpopulations, tissue culture, natural regeneration, seed germination and process ofseedlings, analysis on chemical constituents of seed oil, and accumulated essentialbasic conservation biology theory for domestication and cultivation and artificialforestation of Malania oleifera.The relative sequence of effects of some hydro-thermal index on the geographicdistribution of Malania oleifera made as follow: thermal factor, annually averageprecipitation, annually average sunlight-hours, relative humidity. Extremely hottesttemperature, average temperature during July, annually average temperature, annualaccumulated heat above 10℃and annually average precipitation were the mostsignificantly limiting factors for distribution of Malania oleifera. The most suitablescope for the temperature and the annual precipitation calculated by Peak-Width-Half(PWH) Numeration respectively were 18.0～22.0℃and 1106.5～1585.1mm;The soil with high ratio of sand content and good permeability were suitable forthe growth of Malania olefera. Among six different regions, the content of organicsubstances and total nitrogen in the soil were very rich. The level of Availablepotassium was average and available phosphorus in the soil fluctuates wildly. Soil ofdistribution areas were partly lack of copper and serious lack of zinc and iron. Thechlorophyll proportion in the leaves had a close relationship to the site conditions andthe site conditions of Longhushan Mountain fit for Malania olefera growing betterthan any other sample areas. It was different of contents of same mineral element inthe leaves of Malania olefera because of different areas, but the differences was notnotable. The influence of mineral element and soil elements on Malania olefera wasnitrogen, iron, manganese, zinc, potassium, copper from most to least, and four ofthem were belong to microelement. However, the lack of copper and serious lack ofzinc and iron in the soil influent the growth of Malania olefera.It had been made through the analysis of morphologic and anatomicalcharacteristics of root, stem, leaf, flower, fluid and seed that Malania olefera notonly had the primitive character but also had the evolution character, which had thevital significance on Olacaceae classification. Some morphologic and anatomicalcharacteristics were in common with xerophobous characteristics, which illuminatedthat Malania olefera had some capabilities to adapt to calcific mountain's arid livingconditions.The research on the characters of population and community indicated that thekinds of plant composing in the Malania Oleifera community were not abundance.The dicotyledons were prominent, most of the plants were woody plant, liane andherbage were less.The geographical component of flora was of complicacy. Theprimary members of the Malania Oleifera community were the plants which haveminitype and medium-sized leaves, single leaves, the leather and papery exalted buds.The exoteric characters of community were determined by them .Malania Oleiferawas the preponderant or hypo- preponderant population in this community. The age structure of the population was present as a pyramid standing upside down. It wasrecessionary population and the distributing pattern on space was aggregative.The anthotaxy of Malania Oleifera was cyme, with 8-10 florets, and the floretwas quite small. According to the rating of microspore, the side of Malania Oleiferamicrospore was in the small scale.The microspore was more like a tetrahedron, whilethe polar was more like a triangle. The number of microspore in every anther wasbetween 2600～3600, so the amount of pollen was quite large that it was propitiousto spread and pollination. P/O was 8088 and the breed system was singleheterosexual copulatoryb. The viability of pollen was normally above 50%. The testof pollen culture showed that the viability of pollen was up to the tiptop under thehigher temperature and lower humidity (38℃,40%),while it was weakest under thelower temperature and lower humidity (16℃,40%).The OCI is 4, and the breedsystem was belong to autocopulation. If it was heterosexual copulatory, there must beintermediums for pollination. It was recorded there were more than 40 species ofinsects on the anthotaxy or followers of Malania Oleifera. Under different weather,different living environments and different plants the frequency and rush hour of theinsects to visit the followers were different. Actions of different kinds of insect werealso different. According to the results of the observation, the form of fluid and seedof Malania Oleifera mostly rely on the action of insect pollination, especially thebees.Forty-five individual plants of Malania olefera came from nine populationswhich distributed in Guangxi Zhuang National Autonomous Region and YunnanProvince of China were used to study the influence of polymerase, concentrations oftemplate DNA, annealing temperature, quantity of primer to the RAPD response,and a set of stable RAPD reacting system had been established. The system responsevolume was 2.5μl as total, consisting of template 1μl, 10×buffer2.5μl,2.5mMdNTP1.5μl, 10pm/Mu 1 primers 2μl, E_xTaq enzyme 0.15μl, ddH2O17.85μl.The best response procedure was 95℃/7′→95℃/30″→36℃/30″→72℃/2′70″(expanding and increasing 30 circulation)→72℃/7′. The RAPD hereditymultiplicity researched to the Malania olefera under this reacting system, the result as follows: 61 sites were detected by 6 primers, of which 21(34.4%) werepolymorphism., with low heredity diversity and it was possibly the intrinsicmechanism which induced endangering of Malania oIeifera. RAPD DistancePrograms (version1.04) software was used to analysis heredity diversity of MalaniaoIefera and obtained heredity dendrogram. The result indicated that: the hereditymultiplicity of Malania olefera was correlated with environment, but the correlationwith geography distribution is not prominent.The research on the tissue culture and cell suspension culture showed that thesuitable culture medium for inducing bud was MS supplemented with 1.5mg/L 6-BAand 0.1mg/L NAA, and for the generation-continuing multiplication was MSsupplemented with 1.5mg/L 6-BA and 0.2mg/L NAA. The rooting medium was1/2MS supplemented with 0.5mg/L IBA and the rooting rate was 45.0%. Plantletsurvival after transfer to sand was 52.5%.The induction rate of calli was66.7%～86.6% and the optimum medium was MS medium with 0.5mg/L 6-BA and2.0mg/L 2,4-D. The calli became smallest partical size, friable and had gooddispersion ability after 3 times successive transfer culture, the optimum medium wasMS medium with 0.2mg/L 6-BA and 2.0mg/L 2,4-D. Culturing these particles on sixkinds of MS liquid media with different hormone contents, the optimum medium wasselected basing on he change of the density of single-cell, the density of cellaggrefate and the mass of cell. It was MS medium with 0.2mg/L 6-BA and2.5mg/L2,4-D.Hard seed skin made the seed come out from the mud relatively difficultly andthe root rot serious after transplanting which had close relations with soil water andintensity of illumination. To take seed sow and afforest directly was not suitable forMalania Oleifera. The main reason which caused the reservation rate lower wasartificial tending could not catch up with. The daily photosynthesis velocity ofMalania Oleifera appeared to be one-apex curve, achieves peak value 5.32umol/m~2in 13:00, and was not observed an obvious midday depression. The dailytranspiration velocity of Malania Oleifera also appeared to be one-apex curve andachieves peak value 0.84 mmol/m~2 s between 14:00 and 15:00. The seed of twenty-five individual plants of Malania oIefera came from Bamacounty were crushed, extracted and saponificated, the fatty acids-of them wereesterified by sulfuric acid-methanol. The essential oils from leaves of Malaniaoleifera were extracted by steam distillation (SD) and supercritical fluidextraction(SFE), and the chemical constituents of seed oils and the essential oils ofleaves were analyzed by GC-MS. The results showed that there were some differencein the chemical constituents contents of seed oils of different trees,but there were nosignificant change in the relative contents of oleic acid, docosenoic acid andtetracosenoic acid,the coefficients of them were only 7.32%,7.44% and 8.30%respectively; supercritical fluid extraction(SFE) was a much effective extractingmethod.
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