Soybean diseases can cause substantial yield losses and influence variety selection and crop rotation. In North Dakota there are important diseases of soybean such as Phytophthora, Fusarium and Rhizoctonia root rots, soybean cyst nematode (SCN), and a new disease called sudden death syndrome (SDS). SDS is caused by a fungus Fusarium virguliforme that infects the roots and causes both a root rot and above ground foliar symptoms. This project will focus on identifying resistance to Phytophthora root rot and sudden death syndrome and incorporating resistance into adapted germplasm for this northern region through cooperation with the soybean breeder. These are two diseases where resistance is available within the soybean germplasm. The soybean disease program and the breeding program have worked together in the past incorporating various form of resistance to Phytophthora root rot into public soybean varieties. Because sudden death syndrome is a new disease for ND, resistant varieties have not been developed for this area. This project will identify sources of resistance in maturity groups for this region that can be used in the NDSU soybean breeding programs.

1. Screen NDSU breeding lines for resistance and identify lines with high levels of resistance to Phytophthora root rot.
2. Screen adapted soybean germplasm for resistance to sudden death syndrome and identify sources of resistance that the soybean breeder can use in the development of resistant varieties for this area.

1. Identification of soybean breeding lines with high resistance to Phytophthora root rot.
2. Identification of sources of high levels of resistance to sudden death syndrome in maturity groups for this area.

Updated November 19, 2021:

View uploaded report

This is long term research which will benefit growers in the years to come when sources of resistance are incorporated into public and commercial soybean varieties. Resistance is the most valuable management tool for preventing major losses to important soybean diseases. To illustrate the importance of just one disease, in the United States in 2007 sudden death syndrome was estimated to cause losses of 22 million bushels of soybean.