The Research On Germination Technology And The Fluorescence Characteristics Of Seedlings Of Phoebe Bournei

Phoebe bournei(Hemsl.)Yang, which is an evergreen tree of lauraceae, is a valuable timber tree in our country. The germination rate of Phoebe bournei seeds in the field is low, it has a very close connection with the structure characteristics and material composition of seed itself. The dormancy time of Phoebe bournei seed is long, and the seed is very easy to deteriorate, which is a big obstacle in many aspects, such as afforestation, introduction, breeding and raising seedlings. In addition, the research on excellent provenance selection of Phoebe bournei is also rarely.Although chlorophyll fluorescence technology is widely used and there are many researchs on seedling physiological characteristics of many other species, the fluorescence characteristics of Phoebe bournei is still blank.Based on Phoebe bournei seeds as materials, this paper discuss the dormancy mechanism. At the same time, this paper also determine and compare the seedlings’growth characteristic of different provenances of Phoebe bournei, which provides the theoretical foundation for choosing excellent provenance of Phoebe bournei. The results are as follows:1. Phoebe bournei seeds have physiological after-ripening phenomenon,the structure of seed coat, to a certain extent, affected the permeability of seed and broken seed coat makes the seed breath better. The impact of seed coat to water absorption is not big. The leaching solution of fruit, seed coat and embryo containing germination inhibiting substances, which can inhibit the seed germination rate and the root length of Brassica pekinensis, and the inhibitory effect increased with the increase of concentration of leaching solution, at the same time, the inhibiting substances also can make Brassica pekinensis seedlings appear deformity. Through comprehensive analysis on Phoebe bournei seed we know that Phoebe bournei seed belongs to comprehensive deep dormancy type.2. The extract of Phoebe bournei fruit has the strongest inhibitory effect, and the germination inhibitors are mainly distributed in petroleum ether, ethyl acetate, methanol phase,and the germination inhibitors in seed coat mainly exist in the ethyl acetate phase, and the germination inhibitors in embryo mainly exist in the ether phase.3. According to the results of GC-MS appraisal analysis, a variety of growth inhibitory substances are in the fruit, seed coat and embryo, these compounds are mainly organic acids, esters, alkanes, alkenes, benzene, phenol, etc. Experimental results showed that under the same processing conditions, the organic matter types in extracts of Phoebe bournei:fruit>embryo>seed coat, and sometimes the same organic compounds at the same time exist in the organic phase of fruit, seed coat and embryo.4.Through the determination of seedlings’growth characteristic (plant height, ground diameter, chlorophyll content and ratio, as well as the light quantum yield and initial fluorescence under dark adaptation, fluorescence, etc) of eight different Phoebe bournei provenances, we choose Laifeng, Jinggangshan,Enshi as the excellent provenance, which have the best growth, photosynthetic capacity, stress resistance and each respect ability. That provides certain theoretical basis to further breeding and forecast growth of Phoebe bournei.