Soybean vein necrosis of soybean
Symptoms caused by Soybean vein necrosis virus (SVNV) often begin as yellowing near leaf veins that develops into reddish-brown lesions, causing death of leaf tissue. Lesions follow or spread from leaf veins. Leaf veins may limit lesions, resulting in an angular lesion appearance. Clear, yellow, or dark brown discoloration of leaf veins can occur. Browning of veins may be especially noticeable on the leaf underside.
SVNV is vectored by the soybean thrips and possibly other thrips, and hot, dry weather that favors thrips may cause increased disease spread.
Weeds may provide an overwintering host for SVNV; thrips migrating from the south may also carry the virus. Soybean vein necrosis lesions follow or spread from leaf veins. Image: A. Sisson
Symptoms of soybean vein necrosis on soybean leaves. Image: D. Smith