| Chinese fir belongs to the Taxodiaceae, Cunninghamia, gymnosperms. It is one of the main planting tree species in southern China, and has plays an important position in plantation forestry of China. Clonal forest can retain the advantages of parent lines characters, but there are 2 questions on vegetative propagation of Chinese fir, that is:1st. the yield of cutting is low; 2nd. The technology of Chinese fir tissue culture remains to be further optimized, and only a few clones are applied in production, resulting to limiting the application of good Cunninghamia lanceolata. Clones:As early as 1975, Zhou Tianxiang had reported that Chinese Fir Clones seeding can be obtained by leaf cutting, but so far, there is no application in practical production. Huang Peng further explored the leaf cutting technology and the mechanism of grown-up seedlings, but there are still some problems,such as of the low rate of grown-up seedlings. In view of these problems, we continue to expore the optimization of Chinese fir leaf cutting technology, and try to apply the photoautotrophic micropropagation technology into the leaf of cutting of Chinese fir s. Results shows that:1. Spring and autumn are the best seasons to leaf cutting of Chinese fir, while the worst season is winter. The callus rate, rooting rate, budding rate, seedling rate, average root length and average number in spring are 85.28%,30%,9.17%,3.33%,5.48cm,4.43,respectively; and the callus rate, rooting rate, budding rate, seedling rate, average root length and average number in autumn are 83.05%,31.38%,8.6%,3.05%,5.3cm,4.29. The callus rate, rooting rate and average root length and average number were increasing with prolonging the immersion time rooting powder, but budding rate, seedling rate by rooting powder immersion time is not significantly affected.2. When the ratio of vermiculite to pearlite on Chinese fir leaf cuttings was 2 tol, the callus rate, seedling rate, average root length reaches the maximum, were 77.78%,8.81%,5.39cm,respectively;while vermiculite to pearlite was ltol.the rooting rate reached the maximum,46.67%; and in vermiculite, germination rate, the average root number reached the maximum,were 30% and 1.64.3. T promote callus, rooting and budding, average, average root length, root number of plants,the optimal combination of hormones concentration and processing time are:20mg/L NAA+10 mg/L IBA+20min(A2B2C1D4)、50 mg/L BA+30 mg/L 6-BA+20min(A1B4C4D4)、20 mg/L NAA+10 mg/L IBA+20min(A2B2C1D4)、20 mg/L NAA+50 mg/L IBA+20 mg/L 6-BA+5min(A2B4C3D1)、20 mg/L NAA+20 mg/L6-BA+15min(A2B1C2D3)、40 mg/LNAA+30 mg/L 6-BA+20min(A3B1C3D4),but in photoautotrophic micro propagation conditions, the callus rate, rooting rate, germination rate, seedling rate, average root length, average number are 87.78%,73.07%,46.67%,20%,6.44cm, 1.76,respectively. And the best combinations were:20mg/L NAA+10 mg/L IBA+20min(A2B2C1D4、20 mg/L NAA+30 mg/L IBA+30 mg/L 6-BA+5min (A2B3C4D1),20 mg/LNAA+10 mg/L IBA+20min(A2B2C1D4)、20 mg/L NAA+10 mg/L IBA+20min(A2B2C1D4)、20 mg/L NAA+10 mg/L IBA+20min(A2B2ClD4),10 mg/L IBA+10 mg/L6-BA+10min(AlB2C2D2). Rate of callus, rate, the budding, rate, average root length, average root number are 84.72%,77.78%,43.06%,13.89%,6.26cm,1.98.respectively. Results of autotrophic greenhouses and light conditions, influencing Chinese fir leaf cutting rate of callus, rooting, budding, seeding, average root length, and number of root per the biggest factor are similar.4. The best combination concentration of exogenous hormone and treat timewere:O.lmg/L NAA+0.6 mg/L IBA+0.6 mg/L 6-BA(A1B2C2)、0.5mg/L NAA+0.2 mg/L IBA+0.6mg/L 6-BA (A3B1C2)、0.1mg/L NAA+0.2 mg/L BA+0.2mg/L 6-BA (A1B1C1)、0.1mg/L NAA+0.2 mg/L IBA+0.2mg/L 6-BA (A1B1C1)、0.5mg/L NAA+0.6 mg/L IBA+0.2mg/L 6-BA (A3B2C1)、 O.lmg/L NAA+0.2 mg/L IBA+0.2mg/L 6-BA(A1B1C1),and Callus rate, rooting rate, germination rate, seedling rate, average root length, average number of roots are 71.30%,45.18%,14.81%,5.56%,3.81cmand 1.26, respectively. The result shows that the growth indexes under the different soaking time are better than those under spraying different exogenous hormone.5. For chlorophyll fluorescence parameters of leaf cuttings of Chinese fir,results show that the variation tendency of F0 and Fm is same,which is increasing firstly and then decreasing and then increasing again, but variation tendency of Fm didn’t like that of F0,that during the basic formation of root primordia period,the variation tendency of Fm is downward,and during the rooting phase variation tendency of Fm is decreasing, but during root extending long-term, the trend of Fm is upward. The result also showed that the trend of Fv/Fm are the same as Fv/Fo values,that is decreasing firstly and then increasing, but after a smooth,it recovery to the initial levels. |
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