1. Critical information about the amount of virulence and genotypic diversity that exists among Phakopsora pachyrhizi populations and collected isolates in the United States, and the potential damage that these could cause to soybean yield potential.
2. Information on the extent and stability of soybean rust resistance PIs from the USDA-ARS Soybean Germplasm Collection over time and geographical locations in the U.S.
3. Information on the numbers, locations and effects of Rpp genes conditioning resistance in the soybean PIs with resistance to U.S. rust populations that breeders can use to decide which genes to combine (“pyramid”) to develop cultivars and elite lines with more durable rust resistance.
4. A set of closely related isolines each carrying a known rust resistance gene, which will be more useful than currently available soybean germplasm for characterizing virulence variability in the rust pathogen.
5. Agronomically competitive breeding lines that combine rust resistance with other important traits like good seed yields and resistance to traits like shattering and lodging, which are a problem in many of the original PIs from the Germplasm Collection.
6. Elite breeding lines with pyramided Rpp1 and Rpp3 genes which are adapted to the southeastern U.S.

Progress for each KPI is specified according to the numbered KPIs in section 3.4:
1) A core set of 72 isolates have been collected in the U.S. that largely represents the virulence and aggressiveness of the pathogen (P. pachyrhizi) in the U.S. Yet, U.S. isolates are still being collected, particularly when they show a new degree of virulence. A recent assay of international isolates verified that the U.S. collection contains an adequate sampling of virulence.
2) To date, 54 PI lines have shown significant resistance over multiple locations and years. An evaluation of Glycine soja PI lines found three that show good resistance. A 2014 field test evaluated a set of 156 PI lines with above average resistance – to verify ability to tolerate the current native isolate/pathotype present in the southeast U.S.
3) Six rust resistance genes have been identified including two not previously identified (Rpp 1 to 6). They have been mapped to distinct loci. Two SNP markers for Rpp6 have been verified as useful, though work continues to further refine them. Genetic mapping of resistant material suggests up to another six genes for resistance. These sources continue to be fine mapped to identify the genetic markers behind this resistance.
4) A set of backcross-derived isolines containing Rpp 1 to 4 genes have been developed to further compare the robustness of each gene without concern for the effect of the genetic background itself.
5) The University of Georgia program has advanced lines with Rpp1 and Rpp3 and also in combination together, and with the Roundup Ready 2 trait, both in a MG VII background.