There is a high demand for soybean in African countries, but available varieties are poor yielding. This can be partially attributed to inadequate adaptation of soybean to a tropical climate. Adaptation will require knowledge of allelic combinations of the characterized maturity genes, the long juvenile trait, and stem architecture.
Soybean Innovation Lab researchers work to understand how maturity, long juvenile, and stem architecture traits can influence the adaptation of soybean to low latitudes, specifically in northern Ghana.
The long juvenile trait influences flowering time in low latitudes, which characterize tropical climates. Stem architecture includes the determinate or indeterminate phenotypes, which regulate terminal stem growth. By understanding the influence of these genetic components on adaptation, it may be possible to control season length and improve yield greater than the current African varieties.
To achieve this objective, six populations were initiated. Over 360 experimental lines were created with varying allelic combinations individually controlling the genes of interest. Phenotypic measurements were taken when populations were advancing in a winter nursery in Upala, Costa Rica. The populations segregating for all genes of interest exhibited a potentially advantageous phenotype for a tropical climate: tall, heavily podded plants with ~110 day season.
The lines will be yield tested in four locations in Ghana for two years. Yield components and measurements will be correlated to genotype to understand which allelic combinations produce the highest yielding, adapted soybean variety in that environment. This data can be used when breeders select for the strongest genetic background for future released varieties.