Methods of polyunsaturated fatty acid (PUFA) production by plant tissue culture techniques were investigated. Ribes rubrum calli were induced from leaves, and the highest rates of callus induction and proliferation were observed in B5 modified medium supplemented with 4.0 mg/l 1-naphthalene acetic acid (NAA) and 2.0 mg/l 6-benzyl amino purine (BAP). PUFA accounted for 53.8% (w/w) of the total higher fatty add content in the calli obtained at a culture temperature of 25 degrees C and 59.7% in these obtained at a culture temperature of 10 degrees C. It was demonstrated that fats and oils with a high PUFA content were produced efficiently by the low-temperature treatment.