Grain characteristic, chemical composition, and functional properties of rye were measured in 19 different cultivars grown in one location in up to 3 years. The cultivars included 8 adapted hybrids, 7 adapted population cultivars, and 4 nonadapted population cultivars. The results showed a significant influence of both harvest year and genotype on grain characteristics, chemical composition, and functional properties of the grain. Multivariate data analysis confirmed that the variations in the data were explained by yearly and genotype differences. Calculations of variance components showed that the variations in plant height, harvest yield, and protein content were mainly due to genotype differences and to a lesser extent to differences among harvest years. The kernel weight, hardness index, and content of dietary fiber components, however, were more strongly influenced by the harvest year than by the genotype. Differences in starch properties measured by falling number (FN), amylograph peak viscosity, and temperature at peak viscosity were more strongly influenced by harvest year. The water absorption was strongly influenced by genotype effects, compared to yearly differences. FN and amylograph peak temperature were positively correlated (r ) 0.94). No correlation was found between the water absorption and the relative proportion of water-extractable arabinoxylan (AX) compared to the total AX content. However, the degree of ferulic acid cross-linking showed a negative correlation (r ) -0.70) with the water absorption.

The aim of this study was to measure the variation in dietary fibre (DF) content and composition among different rye varieties grown in the same location in three successive years and to estimate the contributions of genotype and harvest year to this variation. The study included grain from 19 different varieties of rye, of which seven varieties were analysed in all three years. The content of total DF in all samples ranged from 147 to 209 g kg À1 dry matter (dm), with 34-66 g kg À1 being waterextractable (WE) DF and 108-159 g kg À1 being water-unextractable (WUE) DF. The main DF component was arabinoxylan (AX) with a content of 80-121 g kg À1 dm, of which 26-41 g kg À1 dm was WE AX. The ratio of arabinose to xylose (ara/xyl) of total AX ranged from 0.59 to 0.69. The content of b-glucan was 13-22 g kg À1 dm and that of fructan was 45-64 g kg À1 dm. Analysis of the data from seven varieties and three harvest years showed a highly significant influence of harvest year on most DF components. Significant genotype effects were found for the contents of total DF, total AX, b-glucan and fructan and for the ara/xyl ratio of total and WUE AX. Estimation of variance components showed that yearly variations in the contents of total DF, total AX, WUE DF, WUE AX and b-glucan were generally higher (27-55% of total variance) than genotype effects (14-19%). The ara/xyl ratio of total and WUE AX showed a high influence of genotype (46 and 43% respectively). Non-adapted rye varieties with small kernel size had the highest contents of total DF and total AX. The content of b-glucan was positively correlated with kernel weight (r = 0.68), whereas no overall correlation was found between kernel size and the content of DF. As a conclusion, the variation in DF content and composition in this study was significantly influenced by both harvest year and rye genotype.

No abstract

No abstract