Va. Smith, GIBBERELLIN TRANSLOCATION IN PISUM-SATIVUM L .3. BIOLOGICAL AND BIOCHEMICAL CONSEQUENCES OF THE LE MUTATION, Planta, 191(2), 1993, pp. 158-165
The physiological and biochemical consequences of treating Le (tall) a
nd le (dwarf) pea seedlings with varying quantities of the gibberellin
s [H-3]GA20 and GA1 have been investigated. Although the percentage up
take of these compounds from the site of application on the 3-degrees
stipules was low and most of the applied GA remained unmetabolised in
situ, the quantitative relationship between GA translocation and GA do
sage was found to be linear for GA1 but saturating for GA20. The movem
ent of the GAs and their subsequently produced metabolites was mainly
acropetal. They accumulated in greatest quantity in the apical extremi
ties of the shoot. Overall, the extent to which GA20 was metabolished
in le seedlings was considerably less than in Le pea seedlings. Althou
gh all le tissues contained significantly less [H-3]GA1 than their Le
counterparts, phenotypic effects of the le mutation were apparent only
on internode and tendril development. Increased tissue growth, conseq
uent upon GA treatment, was also apparent only in the internodes and t
endrils of le plants. For internodes, GA1 content determined the mid-l
ogarithmic-phase growth rate and, consequently, final length. For tend
rils, GA20 rather than GA1 may be the primary stimulatory agent.