Abstract
Genetic studies conducted in soybean [Glycine max (L.) Merr.] confirmed the presence of a dominant gene controlling the stem-tip necrosis reaction to infection with necrosis-causing strains (G1 and G4) of soybean mosaic virus. This gene, which was derived from the ‘Columbia’ cultivar, is at a different locus from that of Rsv1 and Rsv2. It is assigned the symbols Rsv3 for a hypersensitive (stem-tip necrosis) reaction and rsv3 for a nonnecrotic reaction.