| Ficus concinna var. subsessilis is an arbor plant distributed in the northernmost south subtropic, which is a kind of excellent afforestation trees. This species is also an important indicator plant of climatic and play an important role in the ecosystem. In this study, we, firstly investigated the resources of the ancient ficus in Wenzhou, which were more than 100 years old. Then, the resource status and the main restricted factors of regeneration were evaluated In order to explore causes of ecological degradation, the effect of nutrition and environmental factors on seed germination and seedling growth were carried out..The present results will help us to conserve the wild germplasm and to enhance the population regeneration of Ficus concinna var.subsessilis. The main results and conclusions of this study were stated as follow:1. Resource investigation suggested that unsuccessful regeneration, rot disease and mortality rate might be the primary ecologically degraded factors to this ficus. Principal Component analysis (PCA),shows that locations, historic growth status and soil type have a great effect on the natural resources of the specie in Wenzhou.Correlation analysis shows that the soil type, soil thickness, locations and tree ages have a significant effect on the growth potential of the species. The growth potential of trees growing in the field was significantly higher than that of in the city, and that of trees growing in hillside or waterside was evidently higher than in cement areas. The main factor threatening to the survival of the ancient trees can be ascribed human activities and the destruction of the habitat..2. Under the appropriate temperature and humidity, seeds taken 9 days to germinate and 17 days to the first leave come out. Soaking in the 25℃water, pretreating by 500 mg/l GA, or 20℃ground temperature, and muck and sawdust as substrates that evidently enhanced seed germination. However, the salt stress did the opposite way. Because rotting of fruits were difficulty under natural conditions, the ability of seed germination significantly declined with increase wrapping in the shrinkage pericarp. We suggest that this factor was the main factor limiting the regeneration rate in the field, although they are fruitful every month each year.3. The tree would take at least 20 years to produce fruits. They can produce numerous fruits and seeds every month each year. The poor conditions will reduce fruit productions and seed germination. Trees growing along the river or rivulet have high fruit productions and seed germination. The soil type had great effect on the tree growth. The soil moisture was the main factors affecting the growth of the species. The optimum light intensity of the seedling stage was from 850μmol m-2s-1 to 1500μmol m-2S-1 However, it was always between 85μmol m-2s-1 and 195μmol m-2s-1 under the canopy, which was another reason limiting regeneration. Nitrogen content in substrate plays an important role in the growth and development of seedlings. Whereas P, K content in substrate had no effect.4. The net photosynthetic rate (Pn) was significantly declined under both the low and high concentration of NaCl. The former condition may be caused by stomatal factors, and the latter one may co-dominate between stomatal factors and non-stomatal factors. In addition high NaCl stress may reduce the excitation energy capture efficiency (Fv'/Fm') of PSII reaction center, and may restrict the opening degree of PSII reaction center which will restrain the electron transfer rate and Pn and will evidently boost the photochemical quenching (NPQ), MDA content, SOD and POD activity5. The semilethal temperature test showed that the cold resistance of the species from strong to weak was four-year-old trees, three-year-old trees, biennial trees, and annual trees. After prechilling treatment, the cold resistance of the four different ages was improved.In the process of sudden cold resistance, the changes of physiological and biochemical indexes of the four different ages were consistent. Along with the temperature decline, the leaf membrane permeability, relative conductivity, MDA content and free proline increased; the SOD activity, soluble suger and protein content increased first, and decreased later; and the POD activity did the opposite way. Under cold stress, the physiological and biochemical indexes are different by ages. The activity of SOD and POD, soluble sugar and protein content, and free proline content of three or four-year-old seedlings were significantly higher than that of biennial or annual ones.
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