Soybean Update September 11, 2017

— Written By and last updated by

Soybean Rust Update

from Lindsey Thiessen, Extension Soybean Plant Pathologist

and Jim Dunphy, Extension Soybean Crop Scientist,

NC State University

To date, the nearest Asiatic Soybean Rust (ASR) confirmations have been in Union County, GA, and which is just across the state line from Murphy, NC, and Shelby County, TN, and Hampton County, SC. These reports are greater than 100 miles from soybean producing counties, with the exception of the Union County, GA observation (20 miles from Murphy).

The closest rust on soybeans to Charlotte is still 165 miles, to Elizabeth City is 380 miles, to Fayetteville is 215 miles, to Murphy is 20 miles, to Raleigh is 265 miles, to Washington is 310 miles, to Wilmington is 215 miles, and to Winston-Salem is 235 miles.

Hurricane Irma has the potential to transport rust spores toward North Carolina soybeans. Although we do not expect a significant impact from these potential spores, late planted soybeans may be at risk. If you are concerned that ASR may affect your soybeans (between first bloom and R5), scout fields in an irregular pattern (e.g. zig-zag patterns) beginning 2 weeks after Hurricane Irma passes the region. If you suspect soybean rust, please submit a sample to the Plant Disease and Insect Clinic for confirmation.

We recommend spraying a fungicide to prevent infection of ASR on soybeans if ASR is confirmed on soybeans within 100 miles of your field, and the soybeans are between first bloom and stage R5 (early seed development).

The current status of rust in the continental US can be found anytime at