| Sinowilsonia henryi Hemsl. is treasured and endangered tree species in China. Now, because of the fragmentation of the living environment,it scatters in central and western China, such as Gansu province, Hainan province, Shannxi province, Shanxi province and part of suitable environment areas of Hubei province. Sinowilsonia henryi Hemsl. is endemic single species in our country.《The red book of Chinese plants》 listed it as the secondary protection plants, and was also listed as key protection plant in Shanxi province. It has straight trunk,large blade,plenty of leaves,trivia that looks like streamers in spring, fancy fruit in autumn and high value of landscaping.This experiment studies the genetic structure and genetic information with the method of molecular markers ALPT,thus analysis of Sinowilsonia henryi Hemsl. richness of genetic information and degree of genetic differentiation, then use this to reveal its deeper endangered mechanism, and provides more scientific basis for the protection of the endangered plant resources and more comprehensive information for follow-up study. In addition, due to the biological characteristics of Sinowilsonia henryi Hemsl., itself lead to decline, this experiment established asexual reproduction system by tissue culture. This lay the foundation of the factory nursery and mass production, and also can improve the level of landscaping plants diversity in market.AFLP molecular markers in the experiments of deal the genomic DNA with steps of enzyme digestion, connections, amplification then screened 6 pairs of primers from 64 pairs of primers for polymorphic genetic diversity analysis. The experimental results show that the produced 331 polymorphic bands. On average, each pair of primers produces 55 bands. In this study, Nei’s genetic diversity(H) and Shannon’s information index(I) were found to be 0.192 and 0.325 respectively, indicating a moderate-to-high genetic diversity in species. According to analysis of molecular variation(AMOVA) results, 32% of the genetic variation was shown to be partitioned among populations, demonstrating a relatively high genetic divergence. This was supported by Principal Coordinate Analysis(PCoA) and Unweighted Pair-Group Method with Arithmetic average(UPGMA) analysis. Gene flow was 0.86, indicating the low level of gene exchange between different groups. Moreover, the Mantel test(r = 0.224, P > 0.224) showed that there was no significant correlation between genetic and geographical distances.This experiment studied different culture medium formulas for Sinowilsonia henryi Hemsl. tissue culture the influence of each stage, so as to establish rapid propagation system. In the process of callus induction,axillary bud stem segment, young leaves, embryos were chosen as explant. The optimum culture medium of axillary bud stem section of callus induction are MS + NAA1.0 mg/L + 6- BA1.5 mg/L and MS + NAA1.0 mg/L + 6- BA2.0 mg/L, induction rate can reach 65%.The callus is relatively loose, the volume is bigger. Callus induction by young leaves, browning phenomenon emerged in the early stages and later produced callus quality of a material is hard, difficult for follow-up study. Experimental results show that the axillary bud stem section is more suited for inducing callus. For expanded reproduction, through the amplification coefficient of bud and other indicators, found that the amplification effect of medium MS + NAA0.1 mg/L + 6- BA1.0 mg/L is suitable, amplification coefficient of tube seedlings is high(5.5 or above) and robust. Culture medium with different hormone concentration to inducing root,found that the medium MS + NAA0.1 mg/L + IBA4.0 mg/L can make the rooting rate of more than 60%, rooting number 4-6, can be used in rooting culture. |
