New uses of natural fibres in industrial processes have increased the demand for linseed fibre which is normally discarded. In this investigation, 18 linseed and 10 flax varieties are evaluated for 13 developmental, seed yield and fibre yield traits with a view to identifying suitable genotypes which may have high yields of both seed and fibre, and therefore can be used as dual-purpose varieties and/or are likely to provide a suitable foundation for breeding new cultivars with an ability to produce high yields for seed as well as fibre.

Comparison of linseed and flax varieties has revealed that the two plant types have diversified to a great extent, particularly for those traits which have been subjected to direct or indirect selection during the past decades. However, considerable variation still exists among the linseed and flax varieties, and linseed shows more heritable variation than flax, for both seed and fibre traits. On the other hand, persistent selection of linseed and flax for commercially desirable phenotypes has not modified the genetic correlations to any appreciable level and both crops display almost identical correlations which do not differ significantly for any pair of traits. None of the flax or linseed varieties has shown such outstanding performance for seed yield as well as fibre weight which would have allowed them to be considered suitable for cultivation as a dual-purpose variety. In general, linseed × linseed and linseed × flax crosses would constitute better source materials for breeding high yielding dual-purpose cultivars compared to flax × flax crosses, particularly when seed will be the primary commercial product and fibre/straw a secondary commodity of such varieties.