Effect of perfluidone on metabolism of lipids in maize (Zea mays L.) and sunflower (Helianthus annuus L.)

Abstract

Treatment of germinating maize seedlings with 0.126 mM of the herbicide Perfluidone (Destun) (1,1,1-trifluoro-4′-[phenylsulfonyl]-methanesulfona-o-toluidide) for 2 days in the dark, then 3 days in the light, at 25°C causes decreases in fresh weight, dry weight, shoot length, and in total chlorophyll and carotenoid contents; in contrast, sunflower seedlings seem not to be affected. Perfluidone causes marked decreases in total lipids and in glyco- and phospholipids of maize seedlings. In sunflower cotyledons, total lipids and pigments (chlorophyll, carotenoids) are not affected, but there is an increase in glycolipids at the expense of phospholipids. After Perfluidone treatment, a significant increase in the fatty acid mole ratio (18∶0+18∶1+18∶2)/18∶3 was found for the maize glycolipids, monogalactosyl diacylglycerol (MGD), digalactosyl diacylglycerol (DGD), and sterol glycoside (SG) + esterified sterol glycoside (ESG), and for the phospholipid, phosphatidylcholine (PC). In sunflower seedlings, however, only the fatty acid mole ratio of ESG + SG showed an increase and that of phosphatidylserine (PS) showed a large decrease. The differential response of the two plant species to Perfluidone suggests that the control of linolenic acid biosynthesis may vary depending on plant species and/or on plant tissues.