One hundred and nine accessions of flaxseed (Linum usitatissimum L.) from twelve geographical regions and including oil, fiber, and brown-and yellow-seeded types were used to determine the composition of water-soluble polysaccharides, total carbohydrates, protein, and oil. The content of water-soluble polysaccharides ranged from 3.6 to 8.0%. Neutral monosaccharides of the watersoluble polysaccharide fraction consisted mainly of glucose, xylose, galactose, and rhamnose. The latter varied 3-fold from 8 to 24% of total monosaccharides, although 92% of the accessions had rhamnose values between 10 and 20%. Fucose was a minor component of the water-soluble polysaccharide fraction and displayed the highest coefficient of variation. Xylose was the second largest carbohydrate component, and its mean values were highly correlated with cumulative frequency. Variation of galactose content of the water-soluble polysaccharide fraction of flaxseed from all accessions was normally distributed. Glucose concentration ranged from 21 to 40% and represented the major neutral monosaccharide in flaxseed. The ratio of rhamnose to xylose, an indication of the ratio of acidic t o neutral polysaccharides, ranged from 0.3 to 2.2. Carbohydrate yield and sugar contents of the water-soluble polysaccharide fraction of flaxseed accessions were independent of protein and oil content. Flaxseed accessions, when grouped by geographical region or type, can be differentiated by principal component analysis.

No abstract

No abstract

Flaxseed and its major mammalian lignan precursor secoisolariciresinol diglycoside have been shown to be protective against chemically induced carcinogenesis in animal models. Although flaxseed is the richest source of mammalian lignan precursors, it is not known whether these levels vary with source. Thus the objective of this study was to determine how lignan levels in flaxseed are affected by variety, growing location, harvest year, and seeding time. Ten varieties of flaxseed (AC Linora, Andro, Flanders, Linott, McGregor, Noralta, NorLin, NorMan, Somme, and Vimy) were subjected to 1) in vitro fermentation with human fecal inoculum for 24 hours under anaerobic conditions to assess mammalian lignan production and 2) high-performance liquid chromatography (HPLC) analysis for secoisolariciresinol levels. Three of these varieties (Linott, McGregor, and NorLin) were grown in four locations, seeded early (May) for three different years, and, in one year, seeded early (May) or late (June). Significant differences in lignan production were observed among the different varieties, ranging from 0.96 mumol/g for Linott to 3.15 mumol/g for Somme flaxseed (p < 0.05). Growing location had significant effects on lignan production from all three varieties. Harvest year significantly affected only the Linott variety (p < 0.05), whereas seeding time had no effect. A significant correlation (r = 0.572, p < 0.003) was observed between lignan values obtained from HPLC and in vitro fermentation methods, indicating that HPLC analysis of flaxseed may be used as a predictor of its lignan production levels. Differences due to variety, harvest location, and harvest year of flaxseed should be taken into consideration when tumorigenesis studies are designed.

. 1997. Effects of timings of inoculation with Mycosphaerella pinodes on yield and seed infection of field pea. Can. J. Plant Sci. 77: 685-689. Inoculated field experiments were carried out in 1994 and 1995 to study the effect of the timing of inoculation with Mycosphaerella pinodes (Berk. & Bloxam) Vestergren on disease development, yield reduction and seed infection, in three field pea (Pisum sativum L.) cv. Bohatyr, cv. Scorpio and cv. Triumph. The greatest impact of inoculation on all disease and yield parameters was at the 8-10 node stage in 1994, and at the mid-flowering stage in 1995. The lowest impact of inoculation was at the pod swell stage for both years. When inoculated at 8-10 nodes, midflowering and pod swell stages, M. pinodes reduced yield by 31, 24 and 19%, respectively, in 1994 and 33, 43 and 30%, respectively, in 1995. The 1000-seed weight was not affected by the timing of inoculation; however, all inoculations reduced seed weight in both years. Plant-to-seed transmission of M. pinodes was affected by the timing of inoculation in 1994, but not in 1995. Results of this study suggest that prevention of early infection by M. pinodes will provide the best economic return in a mycosphaerella blight control program on field pea.