6533b836fe1ef96bd12a1caa

RESEARCH PRODUCT

Restitutionserscheinungen an pflanzlichen Meristemen nach Röntgenbestrahlung

subject

description

Young undifferentiated embryos ofEranthis hiemalis were treated with x-rays (1000–4000 r) and their further development was observed. In most of the 4000 r-group the division-activity is completely and irreversibly arrested, but the cell image remains unchanged. The embryos treated with doses between 1000 and 2000 r are also severely damaged, this time undergoing radical disorganization of the tissue, due to degeneration and necrosis. In these embryos small cell groups or even single cells are able to regain their mitotic potency. Meristematic centers (“embryoids”) arise and develop into normal or sometimes misformed viable adventive embryos. This restitution takes place only in x-rayed embryos whose cell coherence is heavily disturbed, a condition which is absent not only after exposure to low (<1000 r) but also to high (4000 r) x-ray doses. It is concluded that the somatic cells of young embryos are totipotent when released from the as yet unknown correlative influences of their environment.