| In this paper, we did a more systematic study about tissue culture for rapid propagation of Photinia fraseri. It included the choice of explants, sterilization methods, adventitious bud induction, its subculture proliferation and rooting of adventitious buds. The rare earth elements Ce(NO3)3 was used and we did a more in-depth study in the Photinia division in the seedling biomass and physiological and biochemical effects. We highlighted the difficulty of rooting in the Photinia and raised the effect of rooting to which MET, culture in dark, phloroglucinol, rare earth elements Ce(NO3)3 and other factors were. Supporting materials such as perlite and vermiculite were used rooting, and a lot of physiological and biochemical changes happened greatly.For example, the enhancement of root activity and root peroxidase activity and the survival rate had been greatly improved in vitro. As a result, we provided a proven method which Photinia could produce quickly. Meanwhile we provided a theoretical basis for plants whose root was not easy to growth in vitro. Now, the key findings of this report were as follows:1. We found that the buds in the third to sixth following the apical bud as explants,had higher budding rate and less browning rate. The best starting medium of Photinia was MS+BA2.0 mg·L-1+NAA0.05 mg·L-1+Sucrose 30g+ Agar7g,pH 5.8～6.2。2. The optimal medium of following proliferation was MS+BA1.0 mg·L-1+NAA0.05 mg·L-1+ Sucrose 30g+ Agar 7g,pH 5.8～6.2. The average multiplication was 4.9 and the average height was 3.2 cm.3. Low concentrations of Ce(NO3)3 elements could improve the quality of Photinia plantlets, so it could promote the growth bud differentiation of Photinia in vitro.And the high concentration of Ce(NO3)3 could impact and inhibit plant growth and development, thus it reduced differentiation of buds of Photinia in vitro, and the number of leaves and fresh weight of a plantlet . 4.In the low concentration range (0.5-5 mg·L-1)of Ce(NO3)3,with the development of Ce(NO3)3 concentration, soluble protein content was increasing, and then with the development of Ce(NO3)3 concentration, soluble protein content was gradually reduced. The concentration of Ce(NO3)3 was greater ,the negative effect of soluble protein was more obvious. Chlorophyll content and POD activity were the same.5.To development rooting rate Photinia fraseri,we explored a variety of factors such as MET, phloroglucinol, Ce(NO3)3 and culture in dark on the rooting rate .We found that 0.5mg/L MET and culture in dark for 7 days promoted rooting. when the 1/2MS+ NAA0.5mg·L-1 + IBA0.3 mg·L-1 +MET0.5 mg·L-1 medium induced rooting, rooting rate was 90%, mean number of roots was 6.5.6.Low concentration of Ce(NO3)3 had been shown to promote seedings growth and rooting quality in Photinia fraseri, and increase the chlorophyll content,improve the number of roots and root total length;whereas higher concentration of Ce(NO3)3 could inhibit seedings growth and development.7.When pearlite and veimiculite were used for supporting materials, mean number of roots and survival rate were better than agar. Mean number of roots was 23.8,rooting rate was 96.6%,and the survival rate of transplant seedlings reached 95.9% when pearlite was used for supporting material. Root vigor and POD activity of different supporting materials were different. Root vigor 225.5μg·g-1·h-1 and POD activity 3.5△A470min-1·g-1 were lowest when agar was used for supporting material. Root vigor 576.159μg·g-1·h-1 and POD activity 27.08△A470min-1·g-1 were lowest When pearlite was used for supporting material. It showed that supporting material of pearlite could maintain higher root activity, a high absorption, transport and other functions. |
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