Evaluation Of Genetic Variation Of Michelia Chapensis Dandy And Research On The Breeding Techniques

M. chapensis ,belonging to Michelia genus in the family Magnoliaceae, is a elite species for timber production and for garden greening. In this paper,the genetic diversity were investigated using RAPD technique,tissue culture of M. chapensis and cross breeding within the genus of Michelia were also studied.The main result are highlighted in the following:1. The total DNA were extracted following a modification of CTAB method with some adjustments. Taguchi method which was widely applied in industrial process design,was used to optimize RAPD Reaction System for M. chapensis.In this work, the signal-to-noise(S/N) and L16(45) orthogonal arrays were employed to reveal the effects of RAPD reaction system.Analysis of variance(ANOVA) decomposed the contribution of individual factors to the experiment response.Optimum levels for each factor were inferred by polynomial regression. A total of 144 individuals representing 6 natural population of M.chapensis were surveyed using 19 RAPD primers.At species level,the percentage of polymorphic bands was 81.98%,Nei's gene diversity was 0.3187 and Shannon index was 0.4751.AMOVA showed that 29.96% of the genetic diversity resulted from differentiation among populations. The coefficient of gene differentiation(Gst)generated by POPGENE was 0.2226. The 6 natural populations of M.chapensis might be divided into 2 groups used UPGMA cluster system,and the genetic diversity of second group is higher than the first.2.The biological characters of floral of some Michelia species were examined,interspecific crossing experiment were made between M.chapensis and M.platypetala, M.yunnanensis, M.crassipes.Some seeds were received and RAPD markers were used to evaluate rates of hybridization.3. Callus and adventitious bud were induced during the tissue culture of M.chapensis, 1/2MS+2,4-D(1.5)+BA(2.0)+NAA(0.2) was used as the induction of callus, 1/2MS+2,4-D(0.3)+BA(2.0)+NAA(0.2) was used as the induction of adventitious bud, the adventitious buds were propagated when subcultured on the medium of 1/2MS+BA(2.0)+NAA(0.2),and growth coefficient of subculture is 1.87,the differentiation of root primordial were investigated on the medium of 1/2MS+NAA(0.5).