Introgression of early maturity alleles from wild soybean (Glycine soja) to domesticated cultivars (Glycine max).

The soybean, Glycine max (L.) Merr., continues to play an important role in Canada’s agriculture sector providing a nitrogen fixing alternative in sustainable crop rotations. As climate change alters the environment there will be a demand for novel sources of ultra-early soybean cultivars that continue to meet seed quality and composition targets set out by domestic and global buyers. Wild crop relatives are being investigated for potential genes in numerous economically important crops. Plant breeders will need to look to the soybeans wild crop relative, Glycine soja Sieb. & Zucc., for added diversity and adaptability. Examples of G. soja have been found with increased salt tolerance, novel resistance mechanisms to soybean cyst nematode, greater resilience in poor soil conditions, and elevated seed protein content. This study aims to investigate early maturity found in a G. soja accession that may harbor novel alleles not found in cultivated G. max. Lines from a G. max/G. soja population are 10 days earlier to beginning of maturity and 11 days earlier to full maturity than the G. max parent. Variability in days to flowering has been observed under artificial conditions (growth chambers) and will need to be further explored in a natural environment (field). While economically meaningful traits are readily found in G. soja, genes controlling unwanted agronomic characteristics will need to be left behind during introgression. Deleterious traits such as dormancy, small seed size, and viney growth habit are being phenotyped to allow identification of the genomic regions responsible. Yellow coloured seeds are more economically valuable but the genetic control of seed coat colour, especially in G. soja, is not fully understood. The diversity of seed coat colours in this G. max/G. soja population provides an opportunity to investigate the trait and its potential link to domestication. Preliminary yield trials suggest that yields of up to 75% of a commercial check can be achieved from this population with earlier maturity. Initial investigation into seed composition shows that this population could provide high protein alleles along with early maturity. Genotype by sequencing will be used to genotype the population followed by identification of quantitative trait loci and potential underlying genes responsible for beneficial phenotypes. Allele-specific markers will be developed to allow for introgression of G. soja traits into G. max cultivars for release into the Canadian market.