Abstract: To investigate the effect of seeding density and nitrogen rates on flaxseed lignan, fatty acids and
yields, field experiments were conducted in 2017 and 2018 at irrigated area in China. Oil flax cultivar Neiya 9 was
planted with 3 seeding rates（3.0×106, 6.0×106 and 9.0×106）and 4 nitrogen rates（0, 16, 32, 48 kg·hm-2）during
the budding stage with irrigation. Results indicated that yield increased significantly with the nitrogen rate under
the same seeding rate. It also increased with the seeding rate under the same nitrogen rate. Oleic acid decreased and
linoleic acid increased with the nitrogen rate, while linolenic acid increased with the seeding rate. Seeding rate and
nitrogen rate had significant influence on oleic acid. Variance analysis results showed that interaction of seeding
density and nitrogen rate had significant effect on both lignan content and oleic acid content. By correlation analy⁃
sis, significant positive correlation was observed between lignan and linoleic, and also between lignan and linolenic
contents. To improve yields and efficiencies of linseed oil, seeding rate as 6.0×106 per hectar and 16 kg·hm-2 nitro⁃
gen rate were recommended under the planting areas with similar irrigated conditions.

Key words: oilseed flax, seeding density, nitrogen, lignan, fatty acids composition, quality, yield