Submitted to: Journal of Euphytica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/21/2017
Publication Date: 2/22/2017
Citation: Landry, E.J., Coyne, C.J., Mcgee, R.J., Hu, J. 2017. A modified mass selection scheme for creating winter-hardy faba bean (Vicia faba L.) lines with a broad genetic base. Journal of Euphytica. 213:72. https://doi.org/10.1007/s10681-017-1843-2.
Interpretive Summary: Faba bean is one of the most important temperate legume crops in the world. Both winter and spring types are grown in many countries but testing and selection in North America of winter type faba bean in lacking. We utilized the National Plant Germplasm System faba bean collection to screen for winter genotypes with adequate winterhardiness for southeastern Washington growing conditions. Although less than 10% of the collection is winterhardy there remains a wealth of diversity for future selection, which may complement currently available commercial cultivars from Europe. These identified accessions with high level of cold tolerance and novel quality traits will be useful for the genetic improvement and adaptation of the faba bean crop. This report highlights the selection gains and resource use efficiency of implementing a modified mass selection technique for improving the winter hardiness or adaptation of faba bean populations. This technique may be useful in other crops as well.
Technical Abstract: Winter-hardy faba bean (Vicia faba L.) from northern Europe is represented by a rather narrow gene pool. Limited selection gains for overwintering beyond a maximum of -25°C have restricted the adoption of this crop. Therefore, the faba bean collection maintained by the USDA-ARS National Plant Germplasm System (NPGS) was utilized to broaden this genetic base by identifying untapped sources of winterhardiness using a modified mass selection scheme. From the initial source population, bulk-harvested from micro-plots of 466 NPGS accessions, four different bulks were formed by harvesting seeds that survived at four locations representing the range of overwintering selection environments of southeastern Washington. These four bulk populations were then mass selected for three cycles based on winter survival along with a selected group of advanced northern European populations or breeding lines at two southeastern Washington locations with divergent climates. This procedure generated breeding materials with a good level of winterhardiness comparable to the northern European populations. We observed that Northern European populations showed slower annual gains in percent survival (<5%) than NPGS bulks (>5%). Further, the frequency of large seeded genotypes (>80 g·100 seed-1) was reduced over time, suggesting an association between seed size and overwintering. The breeding materials generated by this research are useful for the future improvement of faba bean as a pulse or cover crop.