Flax and Linseed - Industrial Crops: Breeding for BioEnergy and Bioproducts - page 242

Target Traits and Current Breeding Goals

Breeding work in flax/linseed is being carried out in agreement with the breeding
objectives. For flax and linseed, these are presented in Table 11.4 [ 59 ]. These
general objectives are practically common in all countries conducting breeding
activities and research. Nearly all of Europe was focused on breeding of flax in the
recent past (such as France, Belgium, the Netherlands, the Czech Republic, Poland,
Russia, Ukraine), while countries like Canada, the USA, and also India were
predominantly interested in linseed breeding. Nevertheless, the characters affecting
yield are common for both types of use, like resistance to lodging and resistance to
fungal diseases and other pests [ 29 ].
The current breeding work in Canada is focused on dual-purpose flax
L. usitatissimum for seed/oil and straw/fiber [ 92 ]. The goal is to find a compromise
proportion between straw and seed yield. Opinions vary on the best way to breed
dual-purpose Linum crops. The breeding work that has been carried out at the
University of Saskatchewan pointed out that linseed can yield only about 33 % of
the fiber yield of flax, whereas flax can yield 60 % of the seed of linseed, so
selection for dual-purpose varieties should be based on flax varieties [ 93 ]. However,
others have recognized that the seed component has been the most important
economically and, considering that fiber length and fineness is less important for
many modern applications, have opted to use linseed x linseed or linseed x flax as
parents for dual varieties [ 94 - 98 ]. Recombinant inbred lines (RILs) from crosses of
linseed x linseed or linseed x flax lines showed positive genotypic correlations for
both high seed/oil and straw/fiber yields [ 99 ]. Foster et al. [ 95 ] also suggested that
there is lower genetic variation for important traits in flax than in linseed. The main
problem in breeding dual-purpose varieties is the different rate of maturation of the
seed and fiber, with the fiber typically reaching optimum maturity around 3 weeks
before maximal seed yield is reached [ 94 ]. Attempts have been made to address the
synchronization of stem and seed maturity through breeding [ 100 , 101 ]. However,
attempts to find viable dual-purpose varieties have been met with only limited
success [ 99 , 102 ].

Table 11.4 Breeding aims for flax and linseed
Flax Linseed

High resistance to lodging High resistance to lodging

High resistance to pathogen complex High resistance to pathogen complex

Middle vegetation period Middle vegetation period

Average unretted stem yield Low stem yield

High content of fiber in the stem High seed yield

High yield of fiber per hectare High content of fat in the seeds

New quality: low linolenic acid content, high
content of lignans (SECO), low content of
cyanogenic glycosides

High fat yield per hectare
New quality: low linolenic acid content, high
content of lignans (SECO), low content of
cyanogenic glycosides