The Effect of Diuron and 5-Aminolevulinic Acid on the Maintenance of Stable Chlorophyll Content in Greening Barley Leaves |
| |
Authors: | Domanskii V P Domanskaya I N Fradkin L I |
| |
Institution: | (1) Institute of Photobiology, National Academy of Sciences of Belarus, Akademicheskaya ul. 27, Minsk, 220047, Belarus |
| |
Abstract: | Chlorophyll (Chl) accumulation and delayed luminescence of PSII were compared in greening barley leaves pretreated and untreated with diuron (DCMU) in the etiolated state, and reactions of two photosystems were studied in the plastids isolated from the pretreated and untreated leaves. The effect of treatment in light of post-etiolated leaves after 40-h illumination with 5-aminolevulinic acid (ALA), on the content of Chl and its precursor, protochlorophyllide (PChld) was also studied. The pretreatment of etiolated leaves with DCMU did not affect the rate of greening and the stable level of Chl content in barley. ALA, when introduced to leaves after the termination of Chl accumulation, increased PChld, but not Chl level. We suppose that the primary cause of greening cessation in etiolated leaves is the inhibition and cessation of the synthesis of apoproteins of pigment–protein complexes. The exhaustion of binding sites for newly synthesized Chl molecules leads to their retention in the so-called retroinhibitory pool of Chl, thus resulting in the inhibition of ALA synthesis by a negative feedback mechanism. |
| |
Keywords: | Hordeum vulgare greening leaves chlorophyll accumulation feedback inhibition 5-aminolevulinic acid diuron delayed luminescence photochemical reactions |
本文献已被 SpringerLink 等数据库收录! |
|