A LOW TEMPERATURE-SENSITIVE MUTANT OF BRASSICA-NAPUS THAT REDUCES THELEVEL OF TRIENOIC FATTY-ACID IN CHLOROPLAST LIPIDS

A mutation of Brassica napus chloroplast lipid metabolism is described which is phenotypically expressed as reduced levels of chlorophyll an d trienoic fatty acids in the acylglycerols of chloroplasts when plant s are grown at low temperatures. Determinations of desaturase activity in double haploid mutant lines suggest that the mutation affects the level of activity of omega 9-, omega 6- and omega 3-desaturases. These desaturase activities are normally induced by periods of low temperat ure; the mutation described appears to result in the loss of this low temperature-induced desaturase activity.