Wheat Diseases

May 28, 1999
Reports of leaf blight on the wheat crop have been very minimal this seasonthat's the good news.

Symptoms of barley yellow dwarf virus (BYDV), however, are prominent in many fields. In a recent tour through Sangamon County with Matt Montgomery of the Sangamon/Menard Extension Unit, I noted that wheat was exhibiting characteristic symptoms of BYDV infection on the flag and flag-1 leaves. The leaves were bright red, fading to yellowish in appearance. This is characteristic of BYDV infection, but actual virus infection can be detected only through ELISA testing in the laboratory. The symptomatic wheat did not appear stunted, which typically indicates spring infection by the virus rather than fall infection. This is good news from a yield-loss perspective, but nevertheless, spring-infected wheat will also have reduced yields. BYDV is managed by the selection of tolerant varieties and planting after the Hessian fly­free date.

Conditions for scab (Fusarium head blight) infection have been fairly good, so you will want to watch for development of this disease now. The wheat is flowering throughout most of the state, and the rains have been very timely for sporulation and infection of the wheat flowers by the fungus.--Suzanne Bissonnette

Author: Suzanne Bissonnette