Objectives
To grow, harvest and return seed from an off-season (winter) breeding nursery for oilseed flax. The seed of these lines will be evaluated to identify superior yielding lines for inclusion in a recurrent selection scheme for increased seed yield for oilseed flax.
Project Description
Oilseed flax (linseed) yields in Saskatchewan have remained stagnant as compared to other crop kinds. The establishment of a winter nursery for oilseed flax has sped up the development of higher yielding varieties by allowing two generations to be grown in one year. In this study early generation yield testing and a modified form of recurrent selection using the bulk method was tested to improve seed yield in linseed. Bulk F3 populations were tested using field trials. F3:4 plants from the highest yielding families were selected from increase plots and grown in a winter nursery as single plant progeny rows or hill plots. F5 seed from harvested rows were used to grow preliminary yield trials. The superior lines were further evaluated using field trials and the best lines inter-crossed to begin another breeding cycle. This method of selection was designed to improve the frequency of favourable alleles for the trait, in this example seed yield, undergoing selection in a population. Improvement in seed yield was positive although modest over the course of the recurrent selection breeding program. Yield potential of check varieties varied from year to year making selection based on seed yield in F3 populations challenging. Notable outputs of this breeding program include one brown linseed line in second year and six lines in first year of co-operative testing in 2013. Interestingly, the outcome of the recurrent selection breeding program for seed yield resulted in FP2363 a high yielding line with concomitant high oil and linolenic acid content. Importantly, the use of a winter nursery reduced the time for varietal development from 10 years to seven years’ time. It is recommended that wider crosses be made to achieve improved gains in seed yield. This approach combined with use of a contra season nursery in oilseed flax will ultimately speed the development of high yielding varieties.
