Factors Affecting Shoot Tip Culture And Regeneration From Hypocotyls Of Nectarine (Prunus Persica Var.nectarina)

In the breeding work of the peach, conventional hybrid techniques are not always satisfied for its long period and large amount of work. With the spring up of modern biological techniques and the applying of gene engineering, that made it possible for us to change the qualities of peach through gene engineering. But first of all, we need establish a high frequent and stable regeneration system of peach.In order to set up regenerate system of peach, the nectarine cultivar Huaguang,Shuguang and Qinguang were used as materials, through studying the factors influenced shoot tip survivalling and multiplying, we have developed the system of the shoot tip culture. Followed to study the factors that affected the regeneration of the hypocotyl of the nectarine variety Qinguang, and induced regeneration adventitious bud in vitro. Then mensurated the activity of antioxidant enzymes on adventitious buds regeneration on hypocotyls of the nectarine variety Qinguang. That researched the adventitious buds regeneration at the cell level preliminarily.Results are as follows:1. The results showed that in the shoot tip culture on Huaguang,Shuguang and Qinguang, the 75% alcohol 30s and the 0.1% HgCl2 1min and the NaClO3 5min was the best for the nectarine shoot tip sterilization and the survival ratio was more high. The time of new shoot sprout was the best for gathering shoot tip, and the pollute rate was lower and adapt to develop.2. The G+6-BA0.50mg/L+ IBA 0.50mg/L was the best for the first culture for the Huaguang and the Qinguang, the survival rate was 98.15% and 72.34%. The G+6-BA 0.50 mg/L+IBA0.125 mg/L was the best for Shuguang, the survival rate was 91.72%.3. The G+6-BA 2.00 mg/L +IBA0.25mg/L was the best for the shoot tip multiply for the Huaguang and Shuguang, the No. of effective shoot was 2.36,2.89. The G+6-BA 1.50 mg/L +IBA0.50mg/L was the best for the shoot tip multiply for the Qinguang, the No. of effective shoot was 3.16.4. By the 7-days norrmal temperature and light beforehand train, the hypocotyls could be used to regenerate the plants as the best and the upper of morphological position and lower showed evident different in this respect. Dark train time from 7 to 14 days was more appropriate to induce callus and then produce adventitious buds. The average number of adventitious buds was higher than other treatment.5. The hypocotyls of Qinguang had the highest regeneration on the medium of G, the number of adventitious buds was highest and performed best on the medium of G+TDZ2.5mg/L+NAA0.5mg/l, the regeneration rate was 38.89%.6. At the early stage of callus differentiation, the SOD activity gradually increased during the hypocotyls regeneration process, and was the highest at 14d, then started to decline. On the contrary, the activity of POD and CAT decreased rapidly, and maintained at a relatively stable level from 7 to 14 days. Both of the two have grown rapidly at the later of the growth of adventitious buds.