| Reasearch progress on garlic(Allium Sativum L.) tissue culture and the significance and characteristics of somatic embryogenesis are summarized in this paper. Methods, including selection of explants and culture media, for establishment of somatic embryogenic cell suspension cultures were investigated. Changes in fresh and dry weights, in cell numbers and other physiological indexes were recorded during suspension culture, and changes in morphological structure and characteristics were examined microscapically. Results indicated:1) Induction of somatically embryogenic callus was best when shoot and root tips were used as explants. The outer protective leaf was the least suitable explant.2) The best media for inducing somatic embryogenesis were MS+2,4-D (0.5mg/L) and MS+2,4-D(2.0mg/L)+KT(0.5mg/L). Callus induction from root and shoot tips was 100% on these media and callus developed normally.3) Cell fresh and dry weights during suspension culture indicated that cell growth rates were quickest during the earliest stages of culture, peaked on day 15 and then decreased. Change in cell number followed an "S"46distribution.4) Paraffin-wax sectioning of tissues indicated that cells of somatic embryonic callus were closely packed with large nuclei and dense cytoplasm; nuclei increased in size with increasing length of the culture period. Cells of non-embryonic callus were loosely packed with small nuclei and thin cytoplasm.5) Regeneration ability was greater for embryonic than for non- embryonic callus, but decreased and even disappeared with increasing length of culture period.6) Cell sap pH showed greatest variation during the early stages of culture, then changed slightly with the increasing cultural time.
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