ACTA PHYSIOLOGIAE PLANTARUM, cilt.23, sa.1, ss.43-47, 2001 (SCI-Expanded)
Vegetatively propagated Crenanthe setosa (Rosc.) Eichler (Marantaceae) plants were grown in plastic pots under laboratory irrigation and water deficit conditions. One set of plants was submitted to water irrigation regularly and another set of plants was submitted to water deficit conditions. After a 28 d water deficit stress, the leaves started to roll. Approximately after 33-35 d, the leaves were tightly rolled. Water stress significantly increased the dry weight of rolled leaves. After the 35 d period of water deficit the open (non-stressed) and rolled (stressed, water deficit) leaves were harvested for lipid content and class compositional analysis. The fatty acids consistently identified in phospholipids and glycolipids as well as in total leaf lipid were 16:0, 18:0, 18:1, 18:2 and 18:3. The 16:0, 18:3 and 18:1 acids in control plant and 18:3, 16:0 and 18:3 acids in rolled leaves were determined as the major fatty acids. While the percentage composition of 16:0, 18:1 and 18:3 acids decreased in rolled leaves, the level of 18:2 acid increased. However, the percentage composition of unsaturation in phospholipid (71 %) and glycolipid (80.4 %) fractions in rolled leaves were found higher than in control leaves. The results show that the degree of unsaturation in phospholipid, glycolipid and total lipid was significantly altered during leaf rolling. The increase in unsaturation degree may regulate membrane permeability and thus adapt the leaves to water stress in the drought environment.