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Abstract: In 1920, a once-thought-to-be-extinct Chinese water-lily species was reestablished from seeds that were unearthed from a lake bed which had been dried up for a thousand years (10). For over twenty years cattle breeders have relied upon frozen-thawed semen to maintain their chosen lines. In experiments with various forms of cells, mortal injury is seriously higher after lyophilization than after freezing. Cells successfully frozen and whose life was safely preserved for the first time by freezing would not survive lyophilization. The organisms tested were a strain of the ciliated protozoa Tetrahymena (3), and four strains of nematodes from four genera (5). The infectivity of Ditylenchus dipsaci to alfalfa seedlings was preserved and the complete life cycle perpetuated in the host as before treatment (4). Lyophilization and/or freezing have become practical and reliable techniques for biologists of various disciplines to maintain the longevity, purity, and existing properties of their invaluable holdings. Of course the living entity itself selects the successful method to be used. Though yet to be evaluated, cases cited indicate that whenever life is successfully suspended, its properties are retained. At the ATCC, fungi are but one of the eight groups (algae, bacteria, bacteriophages, animal cell lines, animal viruses and rickettsiae, plant viruses and protozoa) of organisms maintained in liquid nitrogen storage for long term preservation. To date, though longevity of hundreds of fungal stocks is about ten years, spawns of the cultivated mushroom have been preserved in liquid nitrogen only two years. From our observation and that of others there is no direct evidence which suggests that processing by lyophilization, freezing or liquid nitrogen storage induces genetic changes in the preserved material.
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