U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 Plant Science Research: St. Paul, MN
 close



    Research

                    Research Projects
                                    Publications
                                    Collaborations
                                    News
                People

                    Staff Listing
                                    CareersSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Midwest Area St. Paul, Minnesota Plant Science Research Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications

Title:   Author  item
                                            Samac, Deborah

                                                         - *Debby*item
                                            Lamb, Joannitem
                                            SHEAFFER, CRAIG - University Of Minnesota
  Submitted to: North American Alfalfa Improvement Conference
                                    Publication Type: Abstract Only
                                    Publication Acceptance Date: 7/27/2010
                                    Publication  Date: 7/27/2010
                                    Citation: Samac, D.A., Lamb, J.F., Sheaffer, C.C. 2010. Mycoleptodiscus Crown and Root Rot on Alfalfa in Minnesota and Wisconsin [abstract]. 42nd North American Alfalfa Improvement Conference & 21st Trifolium Conference, July 27-30, 2010, Boise, Idaho.Interpretive Summary:
                                Technical Abstract: Mycoleptodiscus crown and root rot, caused by Mycoleptodiscus terrestris, was identified causing severe disease in seven commercial production fields in southeastern Minnesota and southwestern Wisconsin during the summer of 2009. Both newly seeded fields and established fields were affected. In the field, symptoms consisted of patches of stunted and yellowed plants with poor forage production. Plants from these patches had few lateral and fibrous roots and many of the remaining lateral roots were black and rotted. On many plants crown branches were rotted off, reducing shoot production. In older plants, a V-shaped region of brown decayed material, sometimes with a darker margin, was observed in the crown. In some cases, decay extended into the taproot. Black microsclerotia were found on the crown surface and in rotted crown and root tissues. Although the disease has been known on red clover since the 1950s, it has not previously been reported to cause severe problems in alfalfa production fields. The fungus is highly pathogenic on many legumes including bird's-foot trefoil, white clover, alsike clover, red clover, crimson clover, and soybean, as well as alfalfa. No disease management measures for Mycoleptodiscus crown and root rot have been reported. At this point there are no known resistant alfalfa cultivars. A standard assay is under development so that cultivars can be tested for resistance and for use in a selection and breeding program. A test was established in 2010 at the University of Minnesota Rosemount Research and Outreach Center in a field with high incidence of the disease to evaluate disease resistance and fungicide efficacy.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov