| The successful adoption of faba bean (Vicia faba L.) in southeastern Washington is contingent upon the stability of supply, i.e., yield, and market demand. The lack of regional demand for faba bean has restricted research and development. Therefore, the objective of this research was to explore the adaptation of faba bean to southeastern Washington environmental conditions.;Winter-hardy northern European breeding lines and cultivars were acquired and screened for their ability to overwinter. Additional germplasm was sourced from the USDA-ARS Western Regional Plant Introduction Station (WRPIS) in Pullman, WA, to increase the genetic variation available for improvement of winter-hardiness via a bulk method of selection. Autumn and spring sowing conditions were trialed. Plot yield was most variable across location and year, rather than across populations. Percent survival confounded the differences in plot yield between entries; however, calculating the yield per plant helped to assess yield potential. The mean yield of the spring-sown trial (2.0 t*ha-1) was considerably lower than when autumn-sown (2.8 t*ha-1). The highest plot yield (>8.1 t*ha-1) was obtained from an autumn sowing during the mild winter of 2011-12 at the Central Ferry Research Farm.;The increase in yield of autumn-sown faba bean is mainly attributed to a longer establishment phase and earlier development than when spring-sown. Flowering when daytime high temperature exceeded 25°C was detrimental to pod set and growth. An early spring sowing in March would likely outperform later sowings given regional weather patterns. Earlier flowering and maturing genotypes are needed as the materials tested here exhibited delayed development when spring-sown.;A bulk method of selection improved winter-hardiness for most populations. Response to selection was estimated by comparing pre- and post-selection populations in 2013-14. WRPIS accessions showed the most gain in percent overwintering, ultimately rivaling the winter-hardiness of advanced northern European lines. Adaptive traits present within the germplasm include earlier flowering and maturity that would be important for dry-land agriculture where terminal drought limits the yield potential of northern European winter faba beans with late maturity. |
