Comparative Research On Reproductive Characteristics Of Different Chinese Fir Clones In Tissue Culture

The Chinese fir is an important wood species in the south of China which growing fast with high yield and showing good wood properties for numerous uses. With the continual improving of Chinese fir forests management in recent years, a large number of Chinese fir superior clones were selected from the Chinese fir growing area in the forest of south china, and forestation of superior clone Chinese fir by tissue culture and rapid propagation have been obtained good effects. The difference of genetic characters of different excellent clones of Chinese fir clones resulted in tissue culture reproductive rates is greatly different between different Chinese fir clones. The propagation coefficient of some tissue culture of different Chinese fir superior clones was low, while some of un-superior clones' were high. It was greatly affected widely used of tissue culture seedlings of Chinese fir superior clones. Therefore, how to select superior clones with high genetic quality and propagation coefficient of tissue culture which is easy for tissue culture and factory seedling have became problems badly in need of solution in forestry field.Therefore, based on experiences of tissue culture researches of Chinese fir in the recent more than ten years, selected 11 fine clones of Chinese fir as a study object, which genetic gain is above 30%. By used different hormone proportions as Chinese fir culture medium, the comparative research on reproductive characteristics of tissue culture of different Chinese fir clones were carried out. While the differences of related indexes of tissue culture of different Chinese fir superior clones were discussed, and correlativity between tissue culture and fast-growing character were discussed. It also revealed inner mechanism which led to differences of reproductive characteristics of tissue culture of different Chinese fir clones. It provided scientific basis for improving technology of rapid propagation and promoting tissue culture seedlings of Chinese fir industrialization. The main results of the study were as follows:1,Selected the young terminal shoot of Chinese fir which growing more than two months under field condition as the experiment object, the orthogonal experimental was arranged to search out the optimum extracted from conditions of time of detergent washing, time of disinfectant of 50% alcohol and 0.15% HgCl, and then suitable method for disinfection were obtained which survival rate is66.7%, varying rate and contamination rate dropped to 13.3% and 20%.2,11 fine clones of Chinese fir could grew normally on the induction mediums of MS+6BA0.8mg/l+IBA0.3mg/l, mutiplication medium of MS+6BA0.6mg/l+IBA0.3mg/l and rooting medium of White+NAA0.5 mg/l +IBA0.5 mg/l. The average rooting rate were 42.1%, effective shoot production rate of 1.0cm explants after 4 generations could reach 41.2%. Three culture media could able to satisfy the requirement for Chinese fir tissue culture growth. 3,11 fine clones of Chinese fir were induced on the induction mediums of MS + 6BA0.8mg/l + IBA0.3mg/l, the results was considerable difference. The number of buds was from 1.32 to 6.93 which different as high as five times. The bud lengths were from 0.7cm to 3.12cm and bud width was from 0.21 cm to 0.53 cm. The fragment with wide and multiple buds had more bud primordial, and clones of number 3,1, 6,10 were well induced.4,There were great differences in 11 fine clones of Chinese fir were induced on the mutiplication medium of MS+6BA0.6mg/l+IBA0.3mg/l. The total seedlings were from 30 to 96, effective seedling rate was range from 36.7% to 91.7%. The more effective seedlings, the higher of production efficiency. The propagation coefficient clones of number, 1, 3, 6, 2,7 were high.5,Root growth of 11 fine clones of Chinese fir on rooting medium of White+NAA0.5 mg/l +IBA0.5 mg/l were quite different. The rooting rate was from 38.3% to 95%, the number of root was from 1.3-6.6.The research also showed that clones with small callus and high rooting rate was easy for transplanting tissue culture seedlings. The clones of number 1, 3, 6, 5, 2 grown well.6,Combined with main indexes of multiplication, root and induction tissue culture, the number 1, 3, 6 clones were optimum superior clones, the induction frequency were all reached to 100%, explants of each could produce effective seedlings were 88,75,72 respectively, the rooting rate were 95%,90%,91.7%, they all suitable for rapid propagation.7,The investigation of growth of tissue culture seedling of 6 years old Chinese fir superior clones of number 1, 3, 5, 6, 7 were showed that the average height of 5 poplar clones was 5.67m, while the height of contrast seedlings was only 4.5m. There was no significant difference between clones growth and tissue culture seedling growth.8,The investigation of growth of Chinese fir superior clones from scion nursery cutting afforestation land during different time were showed that the rising curves of 5 poplar clones are almost same and there was no significant different in growth of 5 poplar clones. The growth of each clone had no obviously correlated with diffe rences of tissue culture seedlings.