Eliana Monteverde
This proposal outlines a collaborative research initiative between the University of Illinois at Urbana-Champaign (UIUC) and the Federal University of Viçosa (UFV) aimed at improving resistance to soybean cyst nematode (SCN), Heterodera glycines, the most economically damaging soybean pathogen globally. Since its initial detection in Brazil in the early 1990s, SCN has spread widely, exhibiting diverse populations and high genetic variability across soybean-growing regions. In response, the project focuses on stacking multiple SCN resistance genes to improve durability and broaden resistance in both U.S. and Brazilian soybean germplasm.
Resistance to SCN is primarily derived from genetic sources such as PI 88788 and Peking, each associated with specific resistance genes like rhg1 and Rhg4. While these sources have provided effective resistance in the past, recent studies suggest SCN populations are adapting, especially to PI 88788-derived resistance. Recent work in research and breeding has uncovered several new SCN resistance genes and variants. Among those, two quantitative trait loci (QTL), cqSCN006 and cqSCN-007, derived from wild soybean, appear to provide resistance to most HG types in the Midwest. Although resistance gene stacking has shown promise in enhancing protection and managing SCN virulence, its effects on yield and seed composition remain unclear. This research aims to fill that gap by evaluating how these combinations of SCN resistance genes influence both agronomic performance and seed quality. The primary objective of this proposal is to evaluate the effects of SCN resistance gene stacking on grain yield and seed composition in soybean lines from both Brazil and the U.S.
The project builds on existing collaboration between UIUC and UFV, established in 2019. Two SCN-resistant U.S. lines, LD13-8769 and LD17-30138, were transferred to UFV and crossed with elite Brazilian cultivars to generate four segregating populations (ALC-01, ALC-02, PS-01, PS-02). These populations incorporate multiple resistance QTL, including rhg1-b, Rhg4, cqSCN- 006, cqSCN-007, and a locus on chromosome 10.
Field and greenhouse trials will be conducted in both countries. Brazilian populations will be phenotyped in Brazil for yield and seed composition, while near-isogenic lines (NILs) developed at UIUC will be evaluated at two locations in Illinois. Greenhouse screening at UIUC will assess SCN resistance to two SCN HG types, and genotyping will determine the segregation of resistance alleles. These efforts will help clarify the relationship between gene stacking and agronomic performance under variable SCN pressures. Ultimately, this collaboration will strengthen SCN research capacity in both Brazil and the U.S., supporting the development of more durable resistance strategies to safeguard soybean production in both countries.
Personnel exchanges are central to the project. UFV researchers—including Professor Felipe Lopes da Silva and Ph.D. student Vivian Torres Bandeira Tupper—will visit UIUC 2025/2026 to carry out critical phenotyping and genotyping experiments. They will also receive training to implement these techniques back in Brazil. Professor Eliana Monteverde from UIUC will travel to Brazil in 2026 to further strengthen the collaboration.