Development of 'TN16-520R1': A drought-tolerant soybean cultivar with glyphosate resistance

Authors: Smallwood, Christopher; SHEKOOFA, AVAT - University Of Tennessee; ALLEN, FRED - University Of Tennessee; PANTALONE, VINCENT - University Of Tennessee

Submitted to: Journal of Plant Registrations
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/16/2023
Publication Date: 2/13/2024
Citation: Smallwood, C.J., Shekoofa, A., Allen, F.L., Pantalone, V.R. 2024. Development of 'TN16-520R1': A drought-tolerant soybean cultivar with glyphosate resistance. Journal of Plant Registrations. https://doi.org/10.1002/plr2.20326.
DOI: https://doi.org/10.1002/plr2.20326

Interpretive Summary: Soybean is a major crop grown in Tennessee and the Mid-South. Farmers must consider many things when choosing which soybean variety to grow, including regional adaptation, yield potential, disease resistance, abiotic stress tolerance, quality trait profile, and seed cost. The conventional soybean variety ‘Ellis’, developed by the University of Tennessee, has performed well for many years across numerous environments in Tennessee and the Mid-South. However, many producers prefer to grow soybean varieties with glyphosate resistance to simplify weed control. We developed the soybean variety ‘TN16-520R1’ to match the agronomic performance of the recurrent parent, Ellis, but with the added benefit of off-patent glyphosate resistance, which allows producers to purchase seed without a high technology fee. We describe the development and testing of TN16-520R1 and show that it does indeed possess the most desirable traits exhibited by Ellis, including regional adaptation, high yield, exceptional drought tolerance, resistance to the disease stem canker and the southern root-knot nematode, and field tolerance to the disease frogeye leaf spot. This combination of beneficial traits and broad adaptability make TN16-520R1 an excellent choice as a soybean cultivar for producers, or as a crossing parent for breeders.

Technical Abstract: The glyphosate resistant soybean [Glycine max (L.) Merr.] line TN16-520R1 (Reg. No. ?, PI ?) was released as a high yielding cultivar by University of Tennessee Agricultural Research in 2018. TN16-520R1 is a BC4F2 cultivar derived from the recurrent parent Ellis, with outstanding drought tolerance and a Maturity Group (MG) of V-early. It has white flowers, gray pubescence, tan podwall, and a determinate growth habit. The seeds have buff hila and are yellow with smooth seed coats and contain 40% protein and 22% oil on a dry weight basis. TN16-520R1 has good resistance to lodging and good seed quality (1.8 and 1.6, respectively, on 1-5 scale), and a seed size of 11.8 g per 100 seed. Like Ellis, TN16-520R1 has performed competitively throughout much of the Mid-South over several years, with testing occurring over a six-year period in 102 environments. Further, TN16-520R1 is remarkably like the recurrent parent, Ellis, for yield, maturity, lodging, height, protein, and oil. Also, like Ellis, TN16-520R1 is resistant to stem canker [caused by Diaporthe phaseolorum (Cooke & Ellis) Sacc. var. caulivora K.L. Athow & R.M. Caldwell] and southern root-knot nematode [Meloidogyne incognita (Kofoid and White) Chitwood] and has field tolerance to frogeye leafspot [Cercospora sojina (Hara)]. This combination of beneficial traits and broad adaptability make TN16-520R1 an excellent choice as a soybean cultivar for producers, or as a crossing parent for breeders.