Objective
- Determine optimum conditions required for accelerated growth of flax for a) seed production, and b) reduced generation time
- Evaluate speed breeding to a RIL population for genetic mapping
- Use speed breeding to generate pre-registration lines via: a) integrating MAS and b) selection based on phenotypes
Project Description
Increasing the rate at which new flax cultivars are developed will improve the ability of the flax industry to meet changing market demands and to tolerate climate change. This project will adapt “speed breeding” protocols developed for other crops and apply them to flax breeding for the development of populations ready for pre-registration trials as well as populations suitable for genetic mapping and trait analysis. Significant time savings will be realized by reducing the time required to produce both pre-registration lines and mapping populations.
Speed breeding in flax could have the following advantages, in addition to decreasing the time required to generate candidates for pre-registration trials:
-Increasing the capacity for molecular marker screening at early generation populations resulting in faster introduction of desirable traits.
-Enable screening for abiotic stress tolerance e.g. water deficit stress, high temperature stress,
and early season frost tolerance. Selection pressure condition can be added while growing the
plants under speed breeding. Only the surviving plants will be advanced to the next cycles.
-Reduce the size of the early generation nursery within the breeding program, allowing greater
efforts to be spent on yield testing of advanced lines and on pre-registration trials.
The goal of breeding is to select offspring from crosses between diverse parents that have a desirable combination of traits. Selection decisions are informed by observing desirable phenotypes or by identifying individuals with the genotype(s) of interest. Successful breeding approaches require large numbers of individuals in the early generations (F2 and F3) to ensure that sufficient segregation of alleles and recombination of genes have occurred. The selection process decreases the number of individuals and the genetic diversity of the population with each successive generation. The rate at which this decrease occurs at is termed selection intensity which varies at each generation. Other important considerations factored into breeding programs are the number of generation needed prior to preregistration trials (required to reduce heterozygosity and produce “true breeding” lines) and selection in environments similar to the target environments for the commercial crop production.
