Soybean is one of the major sources of seed protein in the United States and
around the world with an average composition of 40% protein and 20% oil; it is
also a source for essential amino acids, oil and metabolizable energy. The
balanced amino acid profile of soybeans aligns with the dietary needs of humans
and animals and all essential amino acids are present in soybean. Conventional
cultivars of commodity soybean generally have protein values between 38-42%
on a dry weight basis in the seed. One of the most important uses of soybean is
protein rich soybean meal for poultry and swine feed, since it has the highest
level of crude protein among plant-based protein sources. Therefore, increasing
soybean seed protein content is a primary breeding goal. This project aims at
identifying new high protein genes/QTLs and associated DNA markers to use in
breeding programs to facilitate the development of soybean cultivars for
domestic and export markets and improve the profitability of US soybean
producers.
Soybean seed composition is a complex trait that is controlled by multiple genes.
Increasing protein content is problematic due to the negative correlation with oil
content and seed yield. Decades of breeding for increased yield has resulted in a
decline in protein content.
The long-term goal of this project is to develop high protein soybean cultivars
adapted to the Virginia and Mid-Atlantic growing conditions. Specific objectives
for the current phase of the project are to
• Conduct comparative sequence analysis of pairs of protein isogenic lines for
low vs high protein traits
• Develop breeder-friendly and easy to use DNA markers for genes related to
high seed protein content, oil content and essential amino acids in soybean.
• Select high protein breeding lines from a protein advanced generation
segregating population and test for agronomic traits.

The specific objectives of the project are listed below
• Develop breeder-friendly and easy to use DNA markers for genes linked to
protein, oil content and essential amino acids.
• Pinpoint protein genes/QTLs on chromosome 2 and develop DNA markers for
these genes themselves. i.e., perfect markers.
• Selected high protein content breeding lines will be planted in the field and
evaluated for agronomic characteristics.
• Selected elevated oil breeding lines will be planted in the field and evaluated
for agronomic characteristics.

Expected Outcomes/Deliverables
• Selected high protein breeding lines from the biparental population with
agronomic trait data such as height, seed color and lodging.
• Multiple years of protein and oil data on near isogenic lines (NILs) and selected
high protein breeding lines.
• Sequencing data from NILs and selected high protein breeding lines.
• Amino acid content data from seed tissue of NILs and selected high protein
breeding lines.
• DNA markers for protein and oil content genes/QTLs from chromosome 2.
These DNA markers can be used for screening and marker-assisted selection to
identify high protein lines in breeding programs accelerating new cultivar
development process.
• Undergraduate student training Student training is an educational deliverable
of this project.
• Publications in scientific journals and presentations in meetings. These will
provide an opportunity to summarize results and make them available to the
soybean scientific community.