Induced Meiotic Reductions in Root-tips

III. Effect of pyrimidine derivatives, and RNA

Abstract

Pyrimidines and their derivatives (thymine, cytosine, cytidine, uracil and uridine monophosphate) and RNA have been found to effect “meiotic reductions” in the root-tips of Pterotheca falconeri in significant numbers, followed by second division comparable to what occurs in meiocytes during meiosis. The high per-centage of “meiotic reductions” in contrast to reductional groupings of all types taken together in optimal concentrations of these physiological substances is quite meaningful, -particularly when taken in conjunction with the results already obtained with purines and their derivatives and DNA (this journal). The significance of these results will be discussed in the next paper of the series.