Location: Soybean and Nitrogen Fixation ResearchTitle: Registration of ‘N7003CN’ maturity group VII soybean with high yield and resistance to race 2 soybean cyst nematode) Author
Submitted to: Journal of Plant Registrations
Publication Type: Peer reviewed journal
Publication Acceptance Date: 2/15/2011
Publication Date: 9/1/2011
Citation: Carter Jr, T.E., Koenning, S., Burton, J.W., Rzewnicki, P.E., Villagarcia, M.R., Bowman, D.T., Arelli, P.R. 2011. Registration of ‘N7003CN’ maturity group VII soybean with high yield and resistance to race 2 soybean cyst nematode. Journal of Plant Registrations. 5(3):309-317. Interpretive Summary: Soybean Cyst Nematode is the most troublesome pest that farmers face in soybean production. Resistant varieties have been developed over the years to combat this pest. However, race shifts in the nematode have overcome this resistance and rendered soybean varieties completely susceptible. For example, Race 2 has now become a dominant pest in NC and common in the south generally. We currently have NO late-maturity cultivars for the South which have resistance to this Race 2-- That is, until now. N7003CN, just released by USDA-ARS, is highly resistant to the Race 2 cyst nematode. It also has top yields over many yield trials in the South. This combination of Race 2 resistance and high yield in a late maturity cultivar constitutes a real breakthrough in soybean technology. It is being used as parental stock by commercial breeders. Because it is not a GMO Round Up Ready variety, it will likely see commercial use in organic niche markets and in areas where Round Up Ready resistant weeds have proliferated. Several counties ion NC have abundant weeds resistant to Round Up Ready, currently.
Technical Abstract: N7003CN soybean [Glycine max (L.) Merr.] was developed by the USDA-Agricultural Research Service in 2010. It is a high-yielding, maturity group VII, non-transgenic soybean cultivar adapted to the southeastern USA. N7003CN is the first publicly-released Group VII soybean which is resistant to race 2 (HG type 220.127.116.11-) of the soybean cyst nematode (SCN, Heterodera glycines Ichinohe). Race 2 is the dominant type of SCN in North Carolina. N7003CN is also resistant to races 1 and 14 (HG types 2.3- and 18.104.22.168.7, respectively), moderately resistant to races 4 and 5 (HG types 22.214.171.124.6- and 2.5.7-, respectively) and appears to have partial resistance to Race 3 (HG Type 5.7). Molecular analysis of N7003CN identified SSR markers associated with SCN resistance genes rhg1, Rhg4, and Rhg5. During 2005 through 2009 in USDA Uniform Soybean Tests, N7003CN yielded 11% and 2% more than SCN-susceptible control cultivars HaskellRR and N7002, respectively (46 environments). During 2005-2009 in the North Carolina State University Official Variety (OVT) trials, the yield of N7003CN was equivalent to that of SCN-susceptible control cultivar, NC-Raleigh. NC-Raleigh was the highest yielding group VII entry in the OVT. The unusual combination of high yield and SCN Race 2 resistance in group VII maturity makes this cultivar potentially desirable for conventional and organic production and as breeding stock for commercial breeding.