Data di Pubblicazione:
1976
Citazione:
Effects of FC, GA and ABA on the developement of K uptake in germinating radish seeds / S. Cocucci, M. Cocucci - In: The 9 International Conference on Plant Growth substances[s.l] : International Conference on Plant Growth Substances, 1976. - pp. 58-58 (( Intervento presentato al 9. convegno International Conference on Planth growth substances tenutosi a Lausanne nel 1976.
Abstract:
Effects of FC, GA3 and ABA on the development of K uptake in germinating radish seeds
Germination of Rhaphanus sativus seeds is accompanied in its early phase by a consistent
loss to the medium af the main cations. During the first ten hours there is a general efflux .
of K+, Na+, Mg2+, C2+ while inn the following period K+ is actively assumed so that at
eighteenth hour almost no K+ is detected in the external medium.
When seed germination is stimulated by fusicoccin (FC) the development of the capacity of
uptake is markedly anticipated .Moreover inhibition of seed germination by abscisic acid
(ABA) inhibits the development of K+ uptake. The ABA-induced inhibition is reversed by FC and
also, even it to a lower extent, by gibberellic acid GA3.
K+ uptake in germinating radish seed depends on energetic metabolism and on protein synthesis
Respiratory inhibitors such N, N'-dicydohexylcarbodiimide(DCCD) and salicylhydroxamic acid
induced a continuous loss of K from the seed. The presence in the germination medium
of inhibitor of RNA and of protein synthesis such as 3'd-adenosine{cordycepin) and
ciclohexymide (CHI) inhibits the development of K+ uptake .These data suggest that a FC-sen-
sitive, metabolism dependent mechanism of K+ uptake is strictly correlated to the development
of the early phase of germination.
Preliminary data suggest that a K+ activated ATPase present in plasmalemma preparations is
involved in the mechanism of active K+ uptake in the seeds. Lado et al. (Physiol Plantarum
34 ,359 , 1975) showed that FC-induced promotion of germination of dormant seeds is accompanied
by marked drop of the pH in the incubation medium, thus 'suggesting that
the regulation of a H+/K+ exchange mechanism plays an important role in the process of
seed germination.
Tipologia IRIS:
03 - Contributo in volume
Elenco autori:
S. Cocucci, M. Cocucci
Link alla scheda completa:
Titolo del libro:
The 9 International Conference on Plant Growth substances