Quick facts
- Soybean aphid is an invasive pest of soybean that continues to cause economic damage in Minnesota.
- To prevent economic loss, producers commonly apply foliar insecticides when aphid densities reach 250 aphids per plant.
- Aphid-resistant soybean varieties can effectively suppress soybean aphid.
Aphid-resistant genes (Rag genes)
Using aphid-resistant soybean varieties holds promise as a more sustainable approach to soybean aphid management.
Soybean varieties that possess resistance genes, called Rag genes (Resistance to Aphis glycines: Rag1, Rag2, etc.), affect the colonization and population growth of soybean aphid.
Soybean varieties with Rag1 or Rag2 genes have significantly reduced aphid numbers and protected yields across multiple states for years. Varieties with multiple (i.e., pyramided) Rag genes can provide further protection.
Independent university research has shown that varieties can have Rag1 and Rag2 genes without reducing yield, compared to similar aphid-susceptible soybean lines not under aphid pressure.
Resistant varieties offer season-long protection from aphids. In contrast, insecticidal seed treatments (neonicotinoids) only provide temporary protection. This is typically before aphid populations establish.
Using resistant varieties also reduces the likelihood of needing to apply foliar insecticides for soybean aphid.
Availability of aphid-resistant soybean
Commercial varieties containing Rag genes have been available since 2009, but were uncommon among early-maturity soybean varieties developed for Minnesota. There are several brands available in Minnesota.
Soybean varieties carrying Rag genes
Viking Non-GMO Seed
- Brand name: E24Y002 Non-GMO Soybeans
- Relative maturity: 2.4
- Aphid resistance genes: Rag1
- Other characteristics: Phytophthora root rot tolerant; Soybean cyst nematode resistant
- Brand name: IA3054RA12 Non-GMO Soybeans
- Relative maturity: 2.8
- Aphid resistance genes: Rag1, Rag2
Blue River Organic Seed
- Brand name: Organic Blue River 2244A Soybeans
- Relative maturity: 2.2
- Aphid resistance genes: Rag1, Rag2
- Other characteristics: Soybean cyst nematode resistant; Iron deficiency chlorosis tolerant
- Brand name: Organic Blue River 2188A12N Soybeans
- Relative maturity: 2.5
- Aphid resistance genes: Rag1, Rag2
- Other characteristics: Soybean cyst nematode resistant; Iron deficiency chlorosis tolerant
- Brand name: Organic IA3054RA12 Soybeans
- Relative maturity: 2.8
- Aphid resistance genes: Rag1, Rag2
- Brand name: Organic Blue River 14Y4A Soybeans
- Relative maturity: 1.4
- Aphid resistance genes: Rag2
- Brand name: Organic Blue River 19B4A Soybeans
- Relative maturity: 1.9
- Aphid resistance genes: Rag2
- Other characteristics: Phytophthora root rot tolerance
Continue to scout for aphids
It is important to continue scouting for soybean aphids because they can occasionally reach damage levels on resistant plants.
Soybean aphid populations (biotypes) that can overcome aphid-resistance genes exist, but their occurrence varies from region to region and year to year.
Research shows that resistant varieties are compatible with current scouting recommendations for estimating aphid densities and compatible with insecticide use when scouting recommends treatment.
While soybean varieties with single resistance genes, such as Rag1 alone, have effectively suppressed soybean aphid in Minnesota, varieties with pyramided resistance genes, such as Rag1+Rag2, offer more robust protection from resistance-breaking aphid biotypes.
Planting well-adapted aphid-resistant varieties could improve the sustainability of soybean production.
Brace, R.C. & Fehr, W.H. (2012). Impact of combining the Rag1 and Rag2 alleles for aphid resistance on agronomic and seed traits of soybean. Crop Science, 52, 2070-2074. https://doi.org/10.2135/cropsci2011.12.0637
Cooper et al. (2015). Geographic distribution of soybean aphid biotypes in the United States and Canada during 2008-2010. Crop Science, 55, 2598-2608.
da Silva Queiroz, O et al. 2018. Impact of single gene and pyramided aphid-resistant soybean on movement and spatial pattern of soybean aphid (Hemiptera: Aphididae), J. Econ. Entomol. 111: 2946–2955.
Hanson et al. (2016). Sources of soybean aphid resistance in early-maturing soybean germplasm. Crop Science, 56, 154-163. https://doi.org/10.2135/cropsci2015.05.0287
Hanson et al. 2018. Interactions of host-plant resistance and foliar insecticides for soybean aphid management. Crop Prot. 112: 232-238
McCarville, M.T. & O’Neal, M.E. (2013). Soybean aphid (Aphididae: Hemiptera) population growth as affected by host plant resistance and an insecticidal seed treatment. Journal of Economic Entomology, 106, 1302-1309.
McCarville, M.T. et al. (2014). One gene versus two: A regional study on the efficacy of single gene versus pyramided resistance for soybean aphid management. Journal of Economic Entomology, 107, 1680-1687. https://lib.dr.iastate.edu/cgi/viewcontent.cgi?referer=&httpsredir=1&article=1258&context=ent_pubs
Reviewed in 2026