ABSTRACT

We monitored fatty acid compositions of the triacylglycerol (TAG) fractions in flax (Linum usitatissimum L.) seeds cultivated in pots with different seeding dates and nitrogen (N) fertilizing conditions in a temperate region Wakayama, Japan. Five flax cultivars were seeded in early and late December 2017, and in late January 2018, and matured in May, June and July in the order of planting. Three types of N fertilizer were applied for plants seeded in January. Fatty acid profiles in seed TAG fractions were varied among the cultivation conditions. A cluster analysis dissected the fatty acid profiles of the same genotype with different seeding dates. Principal component analyses revealed inverse correlations between saturated and unsaturated fatty acid contents, which could be affected by temperature, N fertilization, and genotypic factors. The highest correlation was observed between α-linolenic and oleic acid contents, which showed a strong inverse relationship across genotypes (r= 0.964, n = 15). The ratio of α-linolenic acid content to that of oleic acid in seeds from plants seeded in early December were higher than those seeded on the other two dates across genotypes. We suppose that seeding date and N supply might be crucial determinants of flax lipid quality in temperate regions.

摘要

我们监测了亚麻（Linum usitatissimum L.) 在日本和歌山温带地区种植在不同播种日期和施氮 (N) 条件的盆中的种子。5个亚麻品种分别于2017年12月上旬和2018年1月下旬播种，按播种先后顺序于5月、6月、7月成熟。一月份播种的植物施用了三种类型的氮肥。种子 TAG 级分中的脂肪酸谱因培养条件而异。聚类分析剖析了具有不同播种日期的相同基因型的脂肪酸谱。主成分分析揭示了饱和和不饱和脂肪酸含量之间的负相关，这可能受温度、施氮和基因型因素的影响。α-亚麻酸和油酸含量之间的相关性最高，r = 0.964，n = 15）。12 月初播种的植物种子中 α-亚麻酸含量与油酸含量的比率高于其他两个日期播种的基因型。我们假设播种日期和氮供应可能是温带地区亚麻脂质质量的关键决定因素。