Flax ( Linum usitassimum L.) of family Linaceae is one of the most important crops, which has been widely used from ancient times. The aim of the study was to examine seed morphological characteristics and fatty acids differences among 13 populations of flax (11 from Iran, one from Turkey and one from USA). We studied six morphological variables of seeds in 50 replications. The methyl esters of seeds fatty acids were analyzed using GC. We detected that the flax seeds shape and color were stable among the populations, whereas ANOVA proved significant variations for all the quantitative seed morphological features. Moreover, we found the main fatty acids of the seed oil remained consistent over the ecological and geographical ranges of the populations, except for Khorasan and Turkey populations differed from the rest by their second main fatty acid. We registered that the amounts of main fatty acids differed among the populations and ANOVA test proved significant differences for most of the identified fatty acids. In addition, significant relationships were registered between some fatty acids. The populations were clustered in UPGMA tree and PCO plot into three distinct groups. CA joined plot and PCA biplot demonstrated that each group had specific type and amount of fatty acid. Therefore, we defined three chemotypes: petroselinic acid, linoleic and linolenic acids, and oleic acid. Although, studied ecological factors influenced some fatty acids amounts, populations from different phytogeographical regions clustered closely as chemotypes. This revealed that populations of each chemotype have been originated from the same diversity center, and some secondary diversity centers exist for flax in the world.

中文翻译：

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亚麻种群的种子形态和脂肪酸组成

亚麻科亚麻(Linum usitassimum L.)是最重要的农作物之一，自古以来就被广泛使用。该研究的目的是检查 13 个亚麻种群（11 个来自伊朗，1 个来自土耳其，1 个来自美国）的种子形态特征和脂肪酸差异。我们在 50 次重复中研究了种子的六个形态变量。使用GC分析种子脂肪酸的甲酯。我们检测到亚麻种子形状和颜色在种群中是稳定的，而方差分析证明了所有定量种子形态特征的显着变化。此外，我们发现种子油的主要脂肪酸在种群的生态和地理范围内保持一致，除了呼罗珊和土耳其种群与其他种群的第二主要脂肪酸不同。我们发现主要脂肪酸的含量在人群中有所不同，方差分析检验证明大多数已鉴定的脂肪酸存在显着差异。此外，在一些脂肪酸之间记录了显着的关系。种群在 UPGMA 树和 PCO 图中聚集成三个不同的组。CA 加入图和 PCA 双图表明每组都有特定的脂肪酸类型和数量。因此，我们定义了三种化学类型：岩芹酸、亚油酸和亚麻酸以及油酸。尽管研究的生态因素影响了一些脂肪酸的含量，但来自不同植物地理区域的种群作为化学型紧密聚集。这表明每种化学型的种群都起源于同一个多样性中心，