| Orchid which is the Orchidaceae plant of monocotyledon is perennial herbage in Botany-taxonomy. Orchid has three growth styles, which is adnascent,terrestrial or saprophytic. Orchidaceae plant can be disparted to terrestrial orchid and aerial orchid. There have upper ronamental value and economic value. Orchidaceae plant is one of the largest groups of flowering plants with as many as 30000～35000 species in nearly 800 genera. But with the passion for orchid, people digs uninterrupted orchid from wild, so as to many orchids on the verge of dying out. Because the propagation of orchid by means of offshoots trationally, which has long periods and has the low propagate rate, so it can not satisfy the internal and external demand. With the development of modern biological technology, tissue culture can be gradually applied to orchid's propagation, which can greatly increase it's propagation coefficient and accelerate it's mass production which can increase the economic value.Geodorum densiflorum which is the plant of Geodorum of Orchidaceae of monocotyledon is a wild orchid which has valuable in exploitation and has many uses ,for example: virescence,beautification,officinal, and so on.The seeds of Geodorum densiflorum were used for explant in the study on the techniques system of aseptic sowing and rapid propagation and morphogenesis of protocorms. The main objects of the study were seeds bourgeon and protocorm-like bodies(PLBs)and adventitious bud induction, proliferation, plantlet rooting and translanting. The results were as follows: (1)The best way of sterilizing for pod was as follows: rinsing 5 min with tap water—immersing in 75% alcohol for 30s—rinsing 2～3 times with sterilized water—disinfecting in 0.1% mercurichloride solution for 10～15 min—rinsing 4～5 times with sterilized water.(2)The disposal of seeds: lacerated the pod using sterilized scalpel and took out the seeds—immersing in 0.1mol/L KOH 10min—rinsing 5～6 times with sterilized water.(3)During the PLB induction,the induction could be through the method of dark culture at the first and light culture following.(4)The optimal culture medium for PLB induction was 1/2MS+6-BA 1.0 mg/L+NAA 0.5 mg/L,in which the induction rate was 95%.(5)The optimal culture medium for PLB proliferation was 1/2MS+6-BA 0.5 mg/L +NAA 0.2 mg/L +1 g·L-1 AC,1/2MS+KT 1.0 mg/L +NAA 0.1 mg/L,in which the rate of PLB proliferation could reach 2.5 and 3.0.(6) The suitable culture medium for PLB differentiation was MS+6-BA 3.0 mg/L +NAA 1.5 mg/L,in which the rate of buds could reach 2.8.(7)The best rooting and strengthening culture medium for adventitious shoots was MS+6-BA 0.2 mg/L +NAA 0.5 mg/L,in which rooting rate was 100%. (8)The transplanting survival rate of plantlets could reach 80% when using lichen, sand, earth (1:1:1) planting medium.Anatomy observation on seeds of Geodorum densiflorum was undertaken. Seed coat was made up of one layer transparent cells. Moreover, morphogenesis during the period of seed germination in vitro was studied. At first, apical cells begin divised. Proembryo was swollen, then seed coat was cracked. Protocorm like body(PLB) was formed. With apical meristem cells of PLB being divided, rhizomeis developed. Epidemal and cortical cells could be divided and formed into lateral meristem under hormone treatment. Then apical and lateral meristem were differentiated into leaf bud. So a whole plantlet was formed. The apical meristem of bud accorded with tunica-corpus theory in the study. Later, the tunica formed into cortex and fibrovascul. The large crystal cells could be observed in the bud. The crystal was formed of oxalate. These crystal formed in vacuole commonly. When appeared lacuna in vacuole, the crystal formed.The seeds of Geodorum densiflorum were used for aseptic sowing in the study, which achieve rapid propagation and it could advance the propagation coefficient. And it also could satisfy consumer's demand. In the study, we filtrated a series of technical parameters, which were basic medium, hormone's kinds and consistency, accessory, and so on. It could establish technic the basic for achieving commercial manufactory. The experiment tried to starting with tissue culture and discussed the character of structure. We discovered the form's process of PLB, which was propitious to advance the propagate coeflicient of Geodorum densiflorum , and it could provide morphologic gist for rapid propation and transplanting of tube seedling of Geodorum densiflorum. There isn't study on the aseptic sowing and rapid propagation and morphogenesis of protocorms in Geodorum densiflorum.
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