For the first time, a comparative study of 5 annual and 6 perennial wild flax species ex situ on
one test plot of the steppe zone of Ukraine is conducted. Similarity of the traits of vegetative and
generative sphere in studied species is established, that indicates the close phylogenetic
relationships between them. It is found that among the these wild species the biggest bush and
largest lamina (300 mm2
) has L. hirsutum while the lowest rates of the habit traits shows L.
pubescens. The given collection covers a wide range of flower color, but most species are
characterized by blue corolla. Flower diameter ranges from 12 to 38 mm, boll diameter - from
2.9 to 7.1 mm, weight of 1.000 seeds - from 0.6 to 5.1 g. The seeds of all studied wild species
contain oil with a fatty acid composition which is characteristic of the Linum genus, but
significantly less than cultivated flax. It is found that L. thracicum has increased content of
linoleic acid (almost 60%), L. hispanicum - higher content of saturated fatty acids (over 15%)
and L. grandiflorum - oleic acid (about 24%). The studied species are of value as a genetic
resource for potential use in gardening, agriculture and pharmaceuticals.