Soybean rust has been confirmed in twelve Arkansas counties: Arkansas, Ashley, Chicot, Drew, Desha, Jefferson, Lee, Lincoln, Lonoke, Prairie, White, and Woodruff. Five of the twelve counties were confirmed this week (9/28) and it is likely that more counties will be added to this list. Disease incidence this week ranged from <1 (1of 25 leaflets) to 16% on R5+ to R7 soybeans. The lowest disease incidence was observed in Lee, White, and Woodruff counties. Though some of these soybeans are past the recommended growth stage of treatment (R6,) abundant spores are being produced that threaten late planted soybeans. See previous reports on this blog for management of younger soybeans that are within or near counties where SBR has been confirmed. Future updates will be posted on this blog and IPM-PIPE.
Figure 1. Distribution of Soybean rust in Arkansas and neighboring states (9/28/12).
