Fluxes of gibberellic and abscisic acids, together with that of adenosine 3',5'-cyclic phosphate, across plastid envelopes during development.

Application of the technique of silicone oil centrifugation to etioplasts and etio-chloroplasts isolated from greening etiolated Avena sativa L. laminae has shown that etioplast envelope membranes are relatively impermeable to gibberellic acid, abscisic acid and adenosine 3',5'-cyclic phosphate. However, there is a marked increase in permeability for all in the early stages of greening, particularly after 2 h. All fluxes are reduced thereafter but a high level of abscisic acid still remains.