Key Technology Of Tissue Culture In Caragana Korshinskii

Caragana korshinskii Kom, a species of Caragana perennial shrub, is cold-resistant, able to bear the drought, aline, alkalinly and barrenly, wind prevention sand fixation species with very strong adaptability. The major object of this study was to exploit the technique systems of tissue culture and rapid propagation for Caragana korshinskii, through the randomised block design, combine analysis of variance, using the stems and seeds as the explant, and the optimal medium and culture program were studied. The major results were as following:1. Lignified branches, spring branches, seedling plants of Caragana korshinskii Kom was disinfected. The results showed that the explants from spring branches were the best among lignified branches, spring branches and seedling plants, which had low contaminated rate, high germination rate and strong vitality.The best disinfection time for lignified branches is 75% alcohol 20 s + 0.1% mercuric chloride 10min,and the germination rate is 72.4%, the polluting rate 6.9%; For spring branches, 75% alcohol 10 s + 0.1% mercuric chloride 10min,the germination rate 81.5%, the polluting rate 20.6%; For seedling plants, 75% alcohol 3 s + 0.1% mercuric chloride 5 min,the germination rate 72.7%, the polluting rate 35.3%,and the damage rate 18.2%.2. The best period of picking the explants was April, when the polluting rate and the damage rate is low and the germination rate is high.3. Among lignified branches, spring branches, seedling plants, mature seeds and embryos, the order of browning degree of all kinds of material was mature seeds, lignified branches, spring branches, seedling plants and embryos. It showed that choosing seedling plants or embryos as explants could reduce browning effectively.4. The optimizing medium for initial culture was MS + 6-BA 0.2 mg/L + NAA 0.1 mg/L + AC 0.3 g/L. After 30 days culture, the average initiation rate was 76.3%.5. The optimizing medium for subculture multiplication was MS+6-BA0.2mg/L+ IAA0.2mg/L + AC0.4g/L. After 30 days culture, the multiplication coefficient was 83.2%.6. In callus induction, the easiness order of callus induction of different explants was leaves, spring branches and stems. In the culture medium of B5 + 6-BA 0.5 mg/L + 2, 4-D1.5 mg/L, the callus induction rate of leaves could reach 100%。7. The best callus differentiation medium was MS + 6-BA 1.5mg/L + NAA 0.5 mg/L, and no dark treatment, with the differentiation rate 7.6%.8. The 1/8 MS + IBA 0.3 mg/L + NAA 0.8 mg/L and sugar 15 g/L was the best medium in rooting culture. After 60 days culture, the rooting rate was 100%; in the medium of 1/2 MS + IBA 1.0 + NAA 0.5 mg/L and sugar 15 g/L, the average rooting number of stems was 6.3. 1/2 MS + IBA 0.3 + NAA 0.3 and sugar 20 g/L was good for root development, with average root length was 7.7 cm .9. For transplantion of plantlets, the best substrate was rotten leaves:sand =1:1, and the survival rate could reach 87.5%, then pearlite:vermiculite = 1:1, with the survival rate of 81.8%, and the sand had the lowest effect, with a survival rate of 58.3%.