| Ilex chinensis Sims(Chinese holly)is the evergreen tree, belongs to the family Aquifolium and the genus Ilex, Nowadays, most Ilex chinensis Sims cultivars were propagated by ways of tissue culture. In traditional plant tissue culture, fluorescent tubes was used as light source and cultures were placed in small, close container during the whole process. This mode not only greatly increased the cost, but also produced high contamination, slow growth and malformed plantlet. This paper systematic study the effect of Light-emitting diode light quality on growth and development of Ilex chinensis Sims plantlets, also the effect of photoperiod on sugar-free Ilex chinensis Sims plantlets.1. Effects of light quality on proliferation and growth of Ilex chinensis Sims were studied, fluorescent as control. The results indicated that proliferating efficency size order of plantlets is:red>red plus blue> fluorescent>blue>yellow, while the red light treatment is66.7%higher than the control; The red and yellow light sources induced higher height of plantlets compared with other treatments and the control. Nevertheless, the best condition for leaf number and pigment contents were to culture under red plus blue light. It showed that using red and red plus blue significantly enhanced the accumulation of carbon-nitrogen compounds.2. Effects of light quality on root induction and growth of Ilex chinensis Sims were studied, fluorescent as control. The results indicated that root numbers and root vigor were greatest with the plants grown under higher red/blue and lower red/blue respectively, especially the root vigor of the plantlets under higher red/blue is33.9%higher than the control. Rooting rate was greater with the plants grown under red LED and fluorescent light. Growth parameters like soot fresh/dry mass, height, intemode length and leaf area were highest with plants grown under red light emitting diodes (LEDs). Plantlets under lower red/blue has the highest SOD and POD activity, while the plantlets under fluorescent has the highest MDA content. All of the treatments led to higher pigment content compared to the fluorescent control.3. Effects of light quality on growth and photosynthetic characteristics of transplanting Ilex chinensis Sims were studied, fluorescent as control. The results indicated that red plus blue light expressed the highest survival rate, the number is95%; transplanted plantlets under red exhibited the highest fresh and dry mass of shoot and root, height and internode length. The best condition for pigment contents, net photosynthetic rate and stomatal conductance were to culture under blue light. However, blue light inhibited the height, shoot diameter and root length significantly. It is observed that growth parameters like accumulation of biomass, root vigor, pigment content and red net photosynthetic rate and stomatal conductance were significantly enhanced with plants under plus blue light compared with the control.4. Light emitting diode (LED) was applied to modulate light intensity and photoperiod of red plus blue light. The effects of photoperiod on growth and photosynthetic characteristics of plantlets in sugar-free culture of Ilex chinensis Sims. The results indicated that growth parameters such as fresh and dry weight of shoot, height, number of leaves and leaf area of plantlets in sugar-free tissue culture of Ilex chinensis Sims increased obviously with the increase of photoperiod; The treatment of14h·d-1photoperiod induced the greatest vigor and elongation of root; Longer photoperiod treatment increased the content of soluble sugar, sucrose, starch and photosynthetic pigments; Nevertheless, it go against the accumulation of soluble protein and amino acid; Pigment content of plantlets leaves increased with the increase of photoperiod; The stomatal conductance were greater under long photoperiod than that under short photoperiod, qP had the same trend, while the qN changed inversely. |
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