Crop Biotech Update

Increasing Palmitic Acid Levels in Cotton Seed Oil thru Downregulation of GhKAS2

September 28, 2016

Palmitic acid (C16:0) makes up approximately 25% of the total fatty acids in the conventional cotton seed oil. However, further improvement in palmitic acid content could provide increased oxidative stability to cotton seed oil, used for making margarine and confectionary products. Qing Liu and a team of researchers from CSIRO Agriculture & Food in Australia aim to increase palmitic oil content by seed-specific RNAi-mediated downregulation of β-ketoacyl-ACP synthase II (GhKASII) in cotton (Gossypium hirsutum).

The team succeeded in increasing the C16 fatty acid content of cotton seed oil, reaching up to 65% of total fatty acids. The elevated C16 levels were comprised of predominantly palmitic acid (51%), palmitoleic acid (C16:1, 11%) and hexadecadienoic acid (C16:2- 3%). Seed germination of the transgenics remained unaffected, despite the alteration of fatty acid composition.

Crossing the high-palmitic lines with previously created high-oleic and high-stearic genotypes demonstrated that these traits could be pyramided. However, elevation of stearic acid is hindered by high levels of palmitic acid.

For more information on this study, read the article in Plant Biotechnology Journal.