Study of Seed Yield and Agronomic Characters in Some F3 Families of Flax (Linum usitatissimum L.)

In order to study seed yield components and agronomic traits in some F3 families of flax (Linum usitatissimum L.), this experiment was conducted in 2014 at the Research Farm of Isfahan University of Technology, Isfahan, Iran. In this experiment, 50 families of F3 generation derived from different crosses were evaluated in a randomized complete block design with two replications. The results showed that there were significant differences among the families for all yield components, seed yield per plant and seed yield per plot.  The means of seed yield per plot for the families ranged from 622 (family of 32) to 2212 kg/ha (family of 37).The range of days to maturity, plant height and seed yield per plant in families was 82 to 97 days, 38 to 71.3 cm and 1.27 to 3.71 g, respectively.  The coefficient of genetic variation for most of the studied traits were slightly smaller or very close to those of phenotypic ones, indicating that most of the observed variation for these traits were due to genetic factors, and thus a moderate to relatively high broad-sense heritability (45.7 to 86.83%) was observed for those traits. The highest and lowest genetic variations were observed for seed yield per plot and days to flowering, respectively. Cluster analysis based on the agronomic traits separated the families into 4 distinct groups, in which the 2nd and 4th groups had the highest mean of seed yield components and, thus seed yield per plot. Generally, the results showed that there was high genetic variation for the studied traits including seed yield and its components and selection can be effective to improve these traits.&nbsp