Yield, SDG lignan, cadmium, lead, oil and protein contents of linseed (Linum usitatissimum L.) cultivated in trials and at different farm conditions in the south-western part of Finland

Linseed varieties were studied in variety trials and under farm conditions in south-western Finland in the years 2007-2010. The variation in yield, oil, protein, SDG lignan, cadmium and lead contents were studied in 8 oil and 2 fibre linseed varieties. Genotypic, environmental and genotype x environment interaction variance estimates were calculated. Fibre varieties 'Belinka' and 'Martta' had higher protein and lower oil contents than oil linseed varieties. The SDG lignan contents of linseed varieties varied between 3635-9560 mg kg(-1). Rather high genotypic variance was found in yield, oil, protein and SDG lignan contents. 'Abacus', 'Helmi' and 'Martta' had the highest SDG lignan contents while 'Laser' had a lower SDG lignan content. Variation in cadmium and lead contents was caused by environmental effects. The highest cadmium contents, 0.82-1.69 mg kg(-1), were found in soils fertilized by wastewater sludge about 20 years ago and at fields with low bottom soil pH (4.1-4.5).