Polyamine levels in buds and twigs of Tilia cordata from dormancy onset to bud break |
| |
Authors: | Arja Santanen Liisa Kaarina Simola |
| |
Institution: | (1) Finnish Forest Research Institute, P.O. Box 18, Vantaa, Finland;(2) Department of Biological and Environmental Science, University of Helsinki, P.O. Box 56, 00014 Helsinki, Finland;(3) Present address: Department of Applied Biology, University of Helsinki, P.O. Box 27, 00014 Helsinki, Finland |
| |
Abstract: | The fluctuations of free and bound polyamines (PAs) were studied in vegetative buds and underlying twigs of linden (Tilia cordata L.) from August to May, to assess the connection between PA levels and seasonal cycles of growth and dormancy. Outer and inner
bud scales and shoot tips (short shoot tips with leaf initials in contiguous short internodes) were analyzed separately, as
were phloem with cortex and xylem with pith tissue from twigs. Seasonal variations in PA levels were present in buds and twigs
during the research period. The most abundant PA in buds and twigs in free and bound forms was spermidine followed by putrescine.
PA amounts were low in buds and twigs in autumn. In twig tissues, free PAs were predominant whereas in bud scales, bound PAs
accumulated over free PAs in autumn, first in inner scales and later in outer scales as well. PA levels did not increase dramatically
during the onset of dormancy in autumn but lower temperatures and probable cold hardening correlated positively with bound
PAs in bud scales. In shoot tips with leaf initials, and contiguous short internodes, free putrescine and spermidine levels
rose simultaneously with bud burst and new growth, while bound PAs diminished quite radically from temporary bud scales and
from growing shoot tips. |
| |
Keywords: | Bud Dormancy Linden Polyamines Putrescine Spermidine Tilia |
本文献已被 SpringerLink 等数据库收录! |
|