Photocontrol of gibberellin levels as related to the unrolling of etiolated wheat leaves

Abstract

The rapid increase in acidic gibberellin-like (GA-like) activity occurring in etiolated wheat (Triticum aestivum L.); leaf tissue in response to red light is phytochrome controlled. The production of some of the GA-like activity appears to possess a similar escapetime from far-red reversibility to leaf unrolling and is sensitive to Amo 1618. Application of these GA-like substances to leaf sections maintained in the dark causes unrolling. Increased GA-like activity can also be detected in non-irradiated portions of partly irradiated leaves.

Localization of phytochrome in etioplasts and its regulation in vitro of gibberellin levels

“…No distinct pattern was distinguishable after 10 min of far-red light. Results of a generally similar nature were recently reported for wheat plastid preparations (13). Unfortunately, the significance of this report cannot be assessed due to the complete absence of any characterization of the plastid preparations used.…”

The Effect of Phytohormones on Chlorophyll(ide), Protochlorophyll(ide) and Carotenoid Formation in Greening Dark Grown Wheat Leaves

“…GibbereUic acid: Treatment of leaves with GA will cause a decreased formation of Chl during irradiation (Szalai 1968, Straub andLichtenthaler 1973), but often the amount of Chl formed is very close to that of the control plants. The biosynthesis of GA itself is mediated through the irradiation and shows a rapid increase during the first period of irradiation of dark grown leaves (Beevers et aL 1970, Cooke andSaunders 1975), This increase can be correlated to leaf expansion and may be important also for Chl formation. In our experiments it seems as if the endogenous GA content is high enough for maximal Chl formation, as there was only a small effect of GA on Chl formation.…”

The light-induced unrolling of the grass leaf - A study of polarity, light-piping and stimulus transmission

“…Due to the fact that the grass leaf is rather thin, a comparatively small difference in the extension of the two leaf sides will result in large changes of the unrolling pattern. The grass leaf has therefore been used as a very sensitive tool to measure effects of various growth hormones and other substances active in cell growth (Foulsen and Beewers 1970, Beewers et al 1970, Loveys and W.areiog 1971, Cooke and Saunders 1975, Sundqvisi and Briggs 1982. With regard to the light-induced unrolling, there are indications of a stimulus transmission (Wagne 1964(Wagne , 1965.…”