Tuesday, November 14, 2006

Identifying and Managing Wheat Rusts.

Jeanne Falk1, Brian Olson1, James Stack2, Douglas Jardine3, Curtis Thompson4, and James Shroyer5. (1) Kansas State Northwest Kansas Research A, 105 Experiment Farm Rd, Colby, KS 67701, (2) Kansas State Univ, Plant Pathology Dept., 4024 Throckmorton Hall, Manhattan, KS 66506, (3) Kansas State Univ , Plant Pathology Dept., 4024 Throckmorton Hall, Manhattan, KS 66506, (4) 4500 E. Mary St., Kansas State University - Plant Pathology, Kansas State University, SW Research Extension Ctr, Garden City, KS 67846-9132, (5) Kansas St. Univ.-Dept. Of Agronomy, Manhattan, KS 66506-5504

Rust diseases on wheat have caused significant yield losses in Kansas in recent years.  During the springs of 2001, 2003, and 2005, stripe rust losses accounted for an average yield loss of 8.6% and a total loss of $259 million.  Stripe rust has quickly become one of the most feared diseases among Kansas wheat producers.  Prior to recent outbreaks of stripe rust, producers were most familiar with leaf rust and to some extent, stem rust.  Producers had little knowledge of stripe rust and thus had many questions about this ‘new’ disease.  Stripe rust is a cool-season rust, attacking earlier in the season than leaf rust.  Because infection occurs at an earlier developmental phase of the wheat plant, potential for yield loss is greater with stripe rust than leaf rust.  Therefore, it is imperative producers recognize differences between stripe and leaf rust.  Additionally, there has been confusion regarding fungicide treatment, time frame of application, and preventative vs. curative properties of fungicides. To help producers better understand the identification and management of rust diseases in Kansas, a new publication was developed titled Identifying and Managing Wheat Rusts.  This publication addresses leaf, stripe, and stem rust.  The ‘Identifying Rust’ section contains photographs of characteristic symptoms for identification.  The ‘Management Decisions’ section outlines major factors affecting rust development and treatment.  Finally, the ‘Control Options’ section contains a list of fungicides and their applicability for treatment of rust outbreaks. By using this guide, producers have a tool for identifying and making decisions regarding the treatment of rusts.  It is being distributed through K-State Research and Extension county offices, and was also included in two of the state’s popular farm magazines, the High Plains Journal and Kansas Farmer.