Premium
Effets physiologiques de ľ atrazine à doses sublétales sur Lemna minor , VII. Incorporation ?acétate‐l,2‐[ 14 C] dans les groupes de lipides et leurs acides gras
Author(s) -
Grenier Gilles,
Beaumont Gaston
Publication year - 1983
Publication title -
physiologia plantarum
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.351
H-Index - 146
eISSN - 1399-3054
pISSN - 0031-9317
DOI - 10.1111/j.1399-3054.1983.tb02772.x
Subject(s) - atrazine , chemistry , lemna minor , biochemistry , polyunsaturated fatty acid , linolenic acid , fatty acid , chromatography , food science , linoleic acid , biology , aquatic plant , pesticide , ecology , macrophyte , agronomy
Physiological effects of sublethal doses of atrazine on Lemna minor . VII. 1,2‐[ 14 C] acetate incorporation into the groups of lipids and their fatty acids. The lipids and the fatty acids of ten‐day old duckweed ( Lemna minor L.), cultivated aseptically in mineral solution containing sublethal concentrations of 0,10 and 0,50 ppm (0.46 and 2.3 μ M , respectively) of atrazine, were analyzed by thin‐layer chromatography and gas‐liquid radiochromatography after 1,2‐[ 14 C] acetate feeding. Sublethal concentrations of atrazine increased the incorporation of radioactivity in total lipids, diacylgalactosylglycerol (DGG), diacyldigalactosylglycerol (DDG), sul‐folipids (SL), phosphatidylglycerol (PG), diacylglycerol (DAG) and triacylglycerol + steroll esters (TAG+SE). The incorporation of acetate‐1,2‐[ 14 C] decreased in phos‐phatidylcholine (PC) and in phosphatidylethanolamine (PE) in the presence of atrazine. The radioactivity increased in total Transic‐hexadecenoic, linoleic and α ‐linolenic acids while it decreased in the other fatty acids. This indicates that the sublethal concentrations of atrazine stimulate the desaturation of fatty acids of L. minor . The radioactivity was strongly incorporated in the α ‐linolenic acid of DGG in the presence of atrazine. The specific radioactivity of α‐linolenic acid was greater in DAG than in PG > TAG + SE > PC > PE > DGG > SL > DDG and it increased in all groupd of lipids analyzed under the influence of sublethal doses of atrazine. The labelling of Trans lchexadecenoic acid of PG and its specific radioactivity increased in the presence of atrazine. These changes suggest that the sublethal concentrations of atrazine stimulate especially the lipid metabolism of the chloroplasts of L. minor and they could explain the increase in the number of grana per chloroplast in treated L. minor . The results are discussed in relation to the biosynthesis of galactolipids.