Development of core collections in soybean on the basis of seed size

Core collections display a large fraction of the diversity contained in large collections in smaller germplasm panels. We used historical data (1973–2015) collected at the World Vegetable Center, Taiwan, for developing soybean ( Glycine max L. Merr.) core collections representing the diversity of the whole collection of 7853 accessions held by the Center. The collection was split into two groups on the basis of the 100 seed weight: large seeded (>25 g or equal to 25 g) and small seeded (<25 g). The large‐seeded group (vegetable soybean/edamame) comprised 456 accessions, while the small‐seeded group contained 7397 accessions. Within these two groups, we developed core collections based on seven quantitative and 14 qualitative traits collected during the autumn season, resulting in a core collection of 112 large‐seeded vegetable soybean accessions and 1480 accessions for the small‐seeded types.