Combining Focused Identification of Germplasm and Core Collection Strategies to Identify Genebank Accessions for Central European Soybean Breeding

Abstract

Environmental adaptation of crops is essential for reliable agricultural production and an important breeding objectives. Genbanks provide genetic variation for the improvement of modern varieties, but the selection of suitable germplasm is frequently impeded by incomplete phenotypic data. We address this bottleneck by combining a Focused Identification of Germplasm Strategy (FIGS) with core collection methodology to select soybean (Glycine max) germplasm for Central European breeding from a collection of >17,000 accessions. By focussing on environmental adaptation to high-latitude cold regions, we selected an environmental precore of 3,663 accessions using environmental data and compared the Donor Population of Environments (DPE) in Asia and the Target Population of Environments (TPE) in Central Europe in the present and in 2070. Using SNP genotypes we reduced the precore into two diverse core collections of 183 and 366 of accessions as diversity panels for evaluation in high-latitude cold regions. Tests of genetic differentiation between precore and core collections revealed differentiation signatures in genomic regions that control maturity, and novel candidate loci for environmental adaptation demonstrating the potential of diversity panels for studying environmental adaptation. Objective-driven core collections increase germplasm utilization for abiotic adaptation by breeding for a rapidly changing climate, or de novo adaptation of crop species to expand cultivation ranges.