Significance of exogenous abscisic acid (aba) in low temperature stress for free fatty acid contents in lipid fraction of potato cultivars 'saskia' and 'desiree' in vitro

• Published in: Zbornik Biotehniske fakultete Univerze v Ljubljani (Slovenia) no. 67
• Main Author: Baricevic, D. (Ljubljana Univ. (Slovenia). Biotechnical Fac., Agronomy Dept.)
• Format: Journal Article
• Language: English
• Published: 1996
• Subjects: ABA; ACIDE GRAS; ACIDOS GRASOS; CELLULE; CELULAS; COMPOSICION QUIMICA; COMPOSITION CHIMIQUE; ESTRES; EXPERIMENTACION IN VITRO; EXPERIMENTATION IN VITRO; FACTEUR DU MILIEU; FACTORES AMBIENTALES; FRIO; FROID; LIPIDE; LIPIDOS; SOLANUM TUBEROSUM; STRESS; VARIEDADES; VARIETE
• ISSN: 0459-6404

Virusfree in vitro potato clones Saskia and Desiree were exposed to low temperature stress (4 deg C) and/or to ABA treatment (7.57. 10** (-5)M) with the aim to evaluate changes in free fatty acid contents on the cellular level. The exogenous ABA at 4 deg C diminished the lipid fraction stearic acid contents (4.8% in Saskia and 5.2% in Desiree) with regard to the ABA untreated plants (9.7% in Saskia and 7.4% in Desiree) and rose percentage of free linoleic acid (33.9% in Saskia and 40.6% in Desiree) with regard to the normal growth temperature (20.4% in Saskia and 24.0% in Desiree). At low growth temperature (4 deg C) the exogenous ABA caused in Saskia a drop (9.0%) and in Desiree an increase (22.3%) of free oleic acid in comparison with the control medium, where plants contained 22.3% (Saskia) or 20.1% (Desiree) of oleic acid. On the contrary, exogenous ABA at 4 deg C strongly rose the free linolenic contents in Saskia plants (35.7%) and did not significantly reduce its proportion in Desiree plants (18.8%) with regard to plants from the control medium at low growth temperature (Saskia 18.8% and Desiree 22.7%). With ABA presence during the 10 days growth period at low stress temperatures we observed an increased unsaturated/saturated free fatty acids ratio (Saskia 4.0; Desiree 4.8) with regard to the normal growth temperature (Saskia 2.8; Desiree 3.0). Unsaturated/saturated fatty acids ratio linarly and negatively correlated with manganese content (r = -0.75; r**2 = 56.3%) as well as with water content (r = -0.79; r**2 = 62.6%) of plant samples. The palmitic acid content was linearly dependent on ABA contents in samples under study (r = 0.98; r**2 = 95.6%). Samples linolenic and oleic acid relative contents were strongly, but negatively correlated (r = -0.98; r**2 = 96.8%).