Research On Release Of Seed Dormancy And The Establishment Of Rapid Propagation System Of Jatropha Sinensis

Idesia polycarpa Maxium is a deciduous tree of the genus Idesia of Flacourtiaceae.It has abundant flowers and leaves,ruddy and smooth fruits,drought and barren tolerance,strong adaptability,is an excellent mountain afforestation and landscape tree species.At the same time,the fruit and seeds of jatropha contain a lot of oil,especially linoleic acid,which is an important woody oil species with high exploitation and utilization value.However,it is difficult for jatropha seeds to germinate spontaneously under natural conditions,the reproduction cycle is long,and there is no relatively complete tissue culture and rapid propagation system,which seriously affects its popularization and application.Therefore,for the purpose of large-scale production,this thesis takes the excellent single plant selected by Sichuan Academy of Forestry as the research object,the seeds were treated with low temperature stratification,variable temperature and plant growth regulator,and the changes of seed inclusions during stratification were investigated,which provided experimental basis for the seed dormancy release and germination of C.atropha.At the same time,in order to propagate excellent varieties and excellent individual seedlings,this thesis further carried out the technical research on the establishment of the rapid propagation system of paulownia,in order to establish a higher quality and efficient seedling technology system for excellent single plant of Paulownia in a short time,and to provide theoretical basis and technical support for the popularization and application of paulownia and its excellent characters.The main results are as follows:（1）Study on the inclusion characteristics of seed dormancy release and seed germination:（1）The germination index was 28.74,the germination potential was 78.33%,and the germination rate was 80.67%higher than that under other constant temperature conditions.At 25℃（12h）/15℃（12h）for 60 days,the germination index was 35.28,the germination potential was 87.33%,and the germination rate was 90.67%.After soaking the seeds with different concentrations of GA₃,IBA and 6-BA for 1 hour and treating them for60 days,the germination rate of C.paulownia seeds was higher than that of the control.The germination rate of 100mg/L GA₃was the best,and the germination rate reached90.33%.The mixed treatment of 100mg/L GA₃and low temperature（10℃）can greatly promote seed germination,shorten germination time（50d）,germination rate reached95.87%,and the effect of the four treatments was the best.（2）The soluble sugar content increased first and then decreased,the starch content decreased first and then increased,and the fat content decreased,indicating that a lot of nutrients were consumed during seed germination.The content of soluble protein in seeds increased during stratification,which proved that stratification treatment could accelerate protein metabolism of jatrotung seeds.（2）Research on the Establishment of Rapid Propagation System of Jatropha sinensis:（1）Disinfection with 75%alcohol for 30 seconds and disinfection with 2%sodium hypochlorite for 8 minutes has the best sterilization effect,and its survival rate is the highest at 78.85%.（2）The optimal medium combination for the cultivation of bacteria-free vaccine was MS+6-BA1.0mg/L+IBA1.0mg/L,and the induction rate was 70.00%.（3）The optimalmediumcombinationforaxillarybudinductionwas MS+6-BA1.0mg/L+NAA1.0mg/L,and the induction rate was 74.33%.The optimal medium combination for axillary bud proliferation was MS+6-BA1.5mg/L+IBA0.5mg/L,and the proliferation coefficient was 10.7.（4）The optimum culture-medium combination for callus induction was MS+6-BA1.0mg/L+NAA1.5mg/L,the induction rate was 66.67%,25℃and full light were the best culture conditions.The best culture medium combination for inducing callus proliferation was MS+6-BA1.0mg/L+NAA1.0mg/L,the proliferation rate was 67.72%,and the culture medium was subsubstituted every 20 days.The best culture-medium combination was MS+6-BA1.5mg/L+NAA0.1mg/L,and the differentiation rate was 54.93%.The optimal medium combination for inducing adventitious bud proliferation was MS+6-BA1.0mg/L+IBA0.5mg/L,and the proliferation coefficient was 2.84.（5）The optimal medium combination for inducing roots of adventitious buds of C.paulownia was 1/2MS+IBA1.0mg/L,which was 92.47%,and the average number of roots was 5.9.