Study On Technology About Tissue Culture And Rapid Propagation Of Pinus Elliottii×Pinus Caribaea

This study intended to establish a culture system that would induce plantlet regeneration of Pinus elliottii across Pinus caribaea . The stem of hybrid pine was 2 years old, which seeds were from Australia. The test work was divided into five parts, including explants sterilization, buds induction, subculture system establishment, roots induction, acclimatization and transplant. The main results were as follows:1. Explants sterilizationImmature seedlings were selected from hybrid pine which were 2 years old and its stem tip were cut into 2cm section. The stems were washed in water for 10 minutes and then put them into the supper-clean bench, washed in sterile water with 2 drop tween-20 for 2 times, in 70% enthanol for 5 seconds, in 0.1% HgCl2 for 6.5 minutes. It was the best way for explants sterilization. The sterile rate was 89.2%.2. Buds inductionGD medium was the best elementary medium for adventitious buds induction of hybrid pine. Adventitous buds were induced in GD medium supplemented with different levels of 6-BA and NAA. The better medium for Pinus elliottii×P. caribaea to induce adventitious buds was GD+6-BA1.0mg·L-1+NAA0.1mg·L-1 +sucrose 20g·L-1 Light application time was 12 hours everyday and light intensity was 40μmoL·m-2·s-1.3. Subculture system establishmentGD medium was the best elementary medium for subculture system establishment. The consistency of 6-BA was lowered as subculture times more. The consistency of 6-BA was 1.0mg·L-1 at the first time, 0.5mg·L-1at the second time and 0.1mg·L-1 of the third time of subculture. Propagation coefficient would be 4-5 after 3-4 times subculture. No vitrification and browning happened during the successive transfer culture.4. Roots formationRoots rate was different by different culture medium and different growing regulators(NAA and IBA). It showed that the rate of root formation reached 45% in culture of GD+IBA 0.1 mg·L-1+sucrose 20g·L-1 5. Acclimatization and transplantTest-tube plantlets were transplanted on the mixed stroma of vermiculite and turfy soil (1:2, V/V)after had been put in natural lighting for a week. Survival rate of the test-tube plantlets would be 80%. Test-tube plantlets would grow 2cm after 10 days.