2007 U of M Research Special Report

Spring Wheat and Barley Disease Screening Nurseries at Crookston

2006 is the twelfth year that inoculated and misted disease screening nurseries of spring wheat and barley have been grown at Crookston, Minn. The continued objective is screening of spring wheat and barley lines for the respective U of M breeding programs in cooperation with the Plant Pathology Department. 

Spring wheat is screened for resistance to fusarium head blight caused by Fusarium graminearum and septoria tritici blotch caused by Septoria tritici. Spring barley is also screened for resistance to Fusarium head blight caused by Fusarium graminearum as well as septoria speckled leaf blotch caused by Septoria passerinii and net blotch caused by Pyrenophora teres. Approximately 10,000 misted rows of nursery were grown at the Northwest Research and Outreach Center in 2006.  Additionally, 1,920 rows of barley were screened for resistance to net blotch near Stephen, MN.

Three different methods of inoculation are used in the nurseries.  Spores are sprayed on the two septoria nurseries commencing at the two leaf stage and repeated at weekly intervals until flag leaf emergence.  Infected straw is spread over the net blotch nursery at the three to four leaf stage.  The FHB nursery is inoculated at the five leaf stage by spreading about 50 pounds per acre of corn seed which has been sterilized and infected with Fusarium graminarium. A second 50 pound application is made 10 to 14 days later.

The screening nurseries have increased in size substantially through the years.  As such, more efficient methods of conducting the nurseries facilitate the increased number of rows.  This past year the planting crew was reduced from three people to one by using a tray system of planting. The application of inoculum was mechanized in the Fusarium and Septoria nurseries requiring only one person for the applications.  An irrigation system which required only ¼ the number of irrigation sprinklers as previously needed was installed. An electronic switch was also developed and installed, which turns the misting system off during periods of rainfall or dew, thereby allowing prolonged daily periods of damp crop canopy while concurrently minimizing the application of water with the irrigation system.

– Galen Thompson, Northwest Research and Outreach Center, Crookston, thomp169@umn.edu