Research On The Soft Branch Cutting Propagation Of Michelia Macclurei Dandy

Michelia macclurei Dandy, also known as Huolinan, is a kind of evergreen tree belongs to Michelia genus of Magnoliaceae family, witch has tall and straight trunk. The flowers are beautiful and white with a rich aroma. Its wood is exquisite and easy to be processed, and it’s also a good fireproof tree species, its leaves, flowers, fruits, seeds by extracting essential oil can be used for a variety of industries, and it is a native tree species with great development value in the south of China.In this paper, we have made a systematic research of green wood cutting propagation techniques by. taking the current-growth half-lignified branches of 2 years old Micheliamacclurei for materiel, and considered the effect from different substrates, different cuttings roughness, and different way of keeping the leaves, different tapes and concentrations of plant growth regulator, different parts of the scion branches, different cutting seasons for rooting cutting, and also investigated the rooting mechanism of Micheliamacclurel by analysis the content of nutrition during the process of rooting and the changing trend of oxidase related to rooting.The main results are as follows:1 Peat soil is the best substrate for cutting rooting of Micheliamacclurel, and the rooting rate could be up to 28.3% if cutting in the autumn. There are significant differences in thickness of cuttings rooting, diameters of the cuttings between 0.15cm and 0.25cm have the highest rate of rooting, and it could be up to 55.0% in the peat soil matrix. The cuttage effects of cuttings which keep two pieces of 1/4 leaves are better than the cuttings keep one piece of 1/4 leaves and the cuttings don’t keep leaf, and the cuttings don’t keep leaf can;t survive. Different types of exogenous hormones have significantly influence on the result of cutting rooting, and the cuttings be treated with 1000mg/L NAA have the highest rooting rate, 1000mg/L ABT1 can significantly improve the rooting quality. The rooting results of cuttings soaked by exogenous hormones are better than the comparison group. The orthogonal experiment results show that the combination of peat soil+500mg/L NAA+cuttings in the upper branches has the highest rooting rate.2 Soluble sugar, starch, soluble protein and other nutrients is an important factor affecting the Michelia macclurel cuttings rooting, and the nutrients level in the cuttings is closely related to rooting. The whole process of adventitious root formation such as callus initiation, root primordium forming, adventitious roots forming and development needs to consume lots of nutrients. Ensure adequate supply of nutrients is a necessary condition for rooting. Nutrient content in rooting process is firstly decreased and then increased.3 The activity of POD, PPO and IAAO were all changed dramatically with the progress of rooting, it’s proved that they are closely related to the rooting progress. The general trends for oxidase activity are:POD and PPO rise at first and then decrease, IAAO firstly decreases and then rise and fall at last. In the adventitious root formation stage, high activity of POD, PPO and IAAO is conducive to the cuttings root, and low activity does not promote the cuttings root. Lower activity of POD, PPO and IAAO is conducive to root elongation growth.