Abstract
Seedlings of Luzula purpurea (2n=6) were placed in contact with H3-thymidine for 30 minutes. After removal of the isotope the roots and leaf primordia were fixed at intervals between 0 and 14 hours. The percentage of labelled mitoses follows a very close curve in roots and leaf primordia. In both tissues the value of G2 is approximately 3 to 4 hours and of S circa 8 hours. DNA replication in the chromosomes of L. purpurea is asynchronous. The discontinuous DNA synthesis discloses that Luzula chromosomes are composed of many segments replicating independently of each other. The results support a polycentric rather than a completely diffuse kinetochore system in this species.
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Bernardini, J.V., Lima-de-Faria, A. Asynchrony of DNA replication in the chromosomes of Luzula . Chromosoma 22, 91–100 (1967). https://doi.org/10.1007/BF00291288
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DOI: https://doi.org/10.1007/BF00291288