| Michelia martinii is an evergreen tree,belongs to Magnoliaceae Michelia,whose trunk is straight and round,whose shape looks like tower with yellow twigs,buds and young leaves,its flower is bright yellow and fragrant,from which aromatic oil can be extracted.In brief,it is a very valuable landscape tree.Because of straight wood textu-re,fine structure,smooth planed surface, it is also considered as an excellent timber s-pecies.So it has good prospects for the development and utilization of Ecological La-ndscape Construction in cityMichelia martinii distributes mainly in southern Henan Province,western Hubei Province,the central south Sichuan Province,the northern south Guizhou Province and other places,and it grows in the valley about 600-1200 meters above sea level. Being excellent timber,many of them have been harvested, thus the saved number is rare.To this end,the thesis conducts the studies of Michelia martinii cutting propagation technology and rooting mechanism in order to explore the most suitable conditions for cutting propagation and provide technical support for the rapid propagation of Michelia martinii,as well as the theoretical backups for the introduction,domestication,promotion and appilcation of Michelia martinii.In this study,the auther takes Michelia martini's branch as the cutting materials,then carries out the breeding experiments with different medium,different hormones,different K-IBA concentrations,different concentrations combrination,different periods for cutting and the change of many nutrients and a variety of enzymatic activity in the process of rooting,finally reaches the following conclusions:(1) The cutting medium affected the rooting rate and the root quality.The most suitable medium for Magnoliaceae Michelia cuttage was perlite+peat (3:1),which produced more fibrous root in cuttage.The subsequence of rooting rate in the cutting medium from high to low was as follow:pearlite+peat (3:1)> Sand+Perlite+Sand (3:1), perlite+ash (3:1)> Perlite.Refers to the domestic and foreign literature and the result of this experimental,we suggested taking pearlite+peat (volume compare 3:1) as the standard matrix for the branch cuttage.(2)The different hormone was good for softwood cuttings,the rooting rate of K-IBA was highest.In the low concentration immersion test of K-IBA and in high concentration fast dip of K-IBA, Michelia martinii could achieve better rooting effects in the treating of 400 mg/L K-IBA soaking 2h and 8000 mg/L K-IBA dippng 15s.The effects of 3000mg/L with different hormones combrination on rooting rate of Michelia martinii was not significant.(3) To semihardwood,the effects of hormone type and concentration on cuttings was significant.The rate of rooting increased with increasing of hormone concentration,and the effect of K-IBA was better than K-NAA.The best treatment combination was 16000mg/L K-IBA,in which the rooting rate was 50%;the average number of rooting was 5.2;the total root length was 236.5cm.(4) Different cutting periods significantly affected Michelia martinii cuttings. Generally, it was better in late October. The highest rooting rate reached 71.9%.(5)The nutrients for the cuttings was in a regular variation as the rooting proceeds, the trend of these indicators in the important period changed dramatically.The application of K-IBA and K-NAA maked the cuttings produce more soluble sugar content than that of controls(CONS),the total nitrogen content was always lower than the controls,and the content of soluble protein achieves peaker than comparison.(6) The POD activity,SOD activity and MDA content in the rooting process displayed different level.Exogenous hormone significantly increased the SOD activity of cuttings and decreased the MDA content in plants,as well as delayed branches aging, which was conducive to the rooting of cuttings.The POD in the body of cuttings showed regular changes. In the rooting process,the difference of POD activity was remarkable,indicating that the formation and development of adventitious roots in Michelia martinii cuttings are closely linked to POD activity.
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