The inhibition and stimulation of DNA synthesis in shoot apices ofChenopodium rubrum L. during photoperiodic induction of flowering |
| |
Authors: | Jana Opatrná B Ho?avka J Ullmann J Krekule |
| |
Institution: | (1) Institute of Expelimental Botany, Czechoslovak Academy of Sciences, Ke dvoru 15, 166 30 Praha 6, Czechoslovakia |
| |
Abstract: | Three short-day inductive cycles bring about inhibition followed by transitional enhancement of growth, not only in roots
and leaves but also in different zones of shoot apical meristem, as shown by measurement of DNA synthesis using3H-thymidine autoradiography. The first inductive cycle resulted in marked inhibition of the cells of the central zone (CZ),
rib meristem (RM), and peripheral zone (PZ). Subsequent enhancement of DNA synthesis occurs in RM during the second inductive
cycle, but in CZ only in the third cycle. The growth activation in PZ is counteracted by decrease in apical dominance which
results in further inhibition of leaf primordia and increases in bud primordia. In plants induced only by one cycle, which
later reverse the vegetative pattern of growth and differentiation, increased DNA synthesis in RM and CZ was not observed.
The significance of inhibitory and stimulatory processes in particular zones of the shoot apex is discussed considering flower
morphogenesis. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|