The Adaptability Of Plants Introduced From Australia And Malesian Region To Xishuangbanna, Southern Yunnan

Xishuangbanna Tropical Botantic Garden (XTBG) provided an important base for the conservation of the species from tropical and subtropical regions. It has already conserved 10, 000 species for the moment. Since the botantic garden was established, we made record for each introduced plant, investigated growth, especially fruit maturation and survival of the introduced plants. Data accumulated in the past several decades could provide guidelines for later plant introduction.The study investigated growth, especially fruit maturation and survival probability of the introduced plants from Australia and Malesian region to discuss their adaptabilities in Xishuangbanna Tropical Botanical Garden (XTBG) from year 1959 to 2001.Our results indicated that the introduced plants from Australia show poor adaptability generally in XTBG. The survival rate and fruit ripening is 5.0% and 3.6% respectively. Survival rate and fruit ripening of the introduced plants from Malesian are 19.8% and 5.7% respectively. Differences in floristic affinities, climates, introducing approaches, acclimatized time, and taxonomic attributions affected the adaptability of these introduced plants.1) The introduced plants from different floristic affinities showed distinct adaptabilities. The plants from northeast Australian have higher adaptability than the plants from the central and southwest Australian. No significant difference in adaptability was found in the plants from different floristic affinities in Malesian region. However, the fruit ripening of the introduced plants from west Malesian is only 1.4%, which is obviously lower than the survival rate of plants form east Malesian and Malesian region.2) We found significant difference in adaptabilities of the introduced plants from different climates zone. Higher adaptabilities was shown in the plants from the tropical wet and dry climate zone and humid subtropical climate zone. However, the plants from the maritime temperate climate, mediterranean climate, and dry climate zone showed poor adaptabilities.3) There is also a significant difference in adaptabilities among the introduced plants from different taxonomic attributions. The introduced Australian plants from Mimosaceae and Palmae have the highest adaptabilities, but the lowest is that from Myrtaceae and Proteaceae; The introduced Malesian region plants from Livistona have the highest adaptabilities, but the lowest is that from Garcinia.4) The comparison of adaptability between direct and indirect introduced plants form Australia showed that the indirect introduced plants have higher adaptabilities. But the same situation have not found in the introduced plants from the Malesian region.5) There is also a discrepancy among the plants have different introduced time, the earlier introduced plants have lower survival rate than the later introduced plants, but the fruit maturation is lower in the later introduced plants.The major factors were found to be climate and floristic affinities. It is concluded that climate and floristic affinity are the principal factors responsible for the success of plant introduction.