| Quercus variabilis is one of the primary sources of industrial cork in China.Presently its stands were established mostly by natural regeneration as a result ofdifficult to storage seeds and conventional vegetative propagation such as cutting.Immature and mature zygotic embryos as well as young stem segments of seedlingswere used as a source of initial explants. We studied on the effects of factors and thehistological and cytological characteristics that related to the somatic embryogenesisand plant regeneration of Q. variabilis. The results would lay a good foundation forpropagation excellent clones, gene preservation, genetic improvement and large-scaleartificial seed production for Q. variabilis. The results were as follows:1. Somatic embryos can be induced on MS and WPM medium with immature zygotic embryos. MS medium with 16 hours light condition was more favorable to embryogenesis. Higher embryogenic responses were gained on MS medium than on WPM medium. Although the embryogenic responses were not significant with light conditions, better quality was reached at 16 hours light condition than at dark condition.2. Direct somatic embryos were gained on MS medium with BAP or TDZ individually. And the quality of the somatic embryos induced on the former was higher than on the latter. Indirect embryos were also gained on MS medium containing 2,4-D, BAP or TDZ individually. Higher inducing rates were obtained on MS medium with BAP and 2,4-D.3. More efficient induction of embryogenic cultures was achieved from the immature zygotic embryos sampled in middle of July. The embryogenic responses from mature zygotic embryos were very low and there was no somatic embyogenesis responses from young stem segments of seedlings. The requirment for combination and concentration of phytohormones changed with the developing time of immature zygotic embryos: immature zygotic embryos sampled in middle of July adapted larger range combination and concentration of phytohormones, but 0.1 mg.L-12,4-D combined with 0.5 mg.L-1 BAP got a better result; those sampled in August needed higher 2,4-D concentration, while those sampled in June needed lower 2,4-D concentration.4. The immature zygotic embryos sampled from different individuals were significant in the embryogenic responses. But there was not significant with different scales sampled from the same individual. Surgery on the immature zygotic embryos was not favorable to embryogenesis and inoculating entire zygotic embryos got higher embryogenic responses. The hypocotyl was important section to embryogenesis, and the embryo segments joined to the hypocotyls got higher embryogenic responses than those without the hypocotyls. It could compensate the decrease of embryogenic response by adding 2,4-D in cutting treats culture.5. MS with 0.5 mg. L-1 BAP could meet the need of proliferation of somatic embryos.Somatic embryos cultured on MS media contained 4～5% sugar got higher maturation rates, while ABA had not significant effect on maturation. The mature somatic embryos were transferred into 1/2MS medium with 16 hours light condition got a better germination rate. Although the rooting rates, shooting rates and geminating rates were no significant at 16 hours light condition and at dark condition, the dark culture was not favorable to leaf spread. 0.3 and 0.7mol.L-1 sorbitol desiccation lasted for 15 days and 4℃ chilling lasted for 15,70 and 90 days had not significant effect on germination rate.6. Histological study showed that secondary embryos derived from epidermal cells and from subjacent cells of somatic embryos by unicellular pathway and multinuclear cells were very common in cotyledon of some somatic embryos and 34-nuclear-cell was found occasionally.7. By analyzing chromosomes with 8 months of continuous subculture somatic callus tissue cell demonstrated that there were 1.87%...
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