Primary Study On Conservation Biology Of The Rare Species Emmenopterys Henryi Oliv.

Emmenopterys henryi Oliv. was a relic species of the monotypic genus Emmenopterys Oliv. of Rubiaceae in China. Due to its limited distribution and restricted population number,this species had been listed as a member of the national grade II rare and endangered plants. Up to date,however,it was still unknown that the study on the biological peculiarity and endangered mechanism of this species. Therefore,this study focused on these issues with respect to ecology,morphology and anatomy,embryology of this species. This study aimed to provide necessary data for the establishment of scientific and effective conservation strategy for this endangered species. The conclusions were as follows:1.Through our investigation for their natural habitats,E. henryi were frequently found growing in the evergreen and deciduous broad-leaved mixed forests at the altitude of 400 m to 1 100 m at Huangshan,Qingliangfeng,and Tiantangzhai of Anhui. They were sparsate and suitable to cool,misty,and humid habitat,with humus-riched soil well-drained along the hillside or furrow rim. The richness,diversity index and evenness of E. henryi was relatively low,and higher ecological dominance. In most of the E. henryi populations ,the young individuals were few,the adult ones were in an inferior position in community succession,and the population size was tending to decline. The data of field plot showed that the community was unstable and secondary one,which had a tendency of degeneration.2.The leaf of E. henryi had the general characters of typical bifacial leaf and mesophyte. Each epidermis consisted of a row of irregular epidermic cells which arranged closely and the horny layers of the cells were thin. The stoma only existed in lower epidermis covered by sparse cellular epidermal hair,and their type was irregular. The characters of leaf showed that it was adapt to the environment in which it lived,and it was sun plant.3.Seed germination biology of E. henryi was studied. The results showed:1) The seed of E. henryi was dormant. The potential ability of germination (92%) by the method of red ink was much higher than its effective level of germination in its habitat soil. This result was consistent with few seedlings in its natural habitats through our investigation. 2) Uneven germination of seeds of E. henryi was due to uneven developed degree of seeds. In full-illumination and under the constant temperature of 25℃,the seeds germinated fastest,and the embryoes also developed fastest. 3) The seeds of E. henryi were light-sensitive seeds and could not germinate in dark whether the temperature was constant or not. The germination rates of the seeds was very low under the natural conditions which defected enough illumination.4.The optimum germination culture medium for the mature embryo of E. henryi was MS+6-BA0.5+IBA0.5. The optimum adventitious shoots induction and proliferation culture medium was MS+KT1.0+IBA0.5. The most suitable transplanting media of test-tube seedling was the mixed media of peat and pearlite at the rate of five to one.5.The threatening factors were analyzed and some countermeasures for effective species preserving were also proposed , including in situ conservation,ex situ conservation,building up seed bank and genome resource bank et al. In order to protect this endangered species,studies of physiology,genetics,PVA analysis,and so on should be made at the same time. It might be the key reason that its'habitat was destroyed. E. henryi could be also introduced at botanical garden and arboretum etc.