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
 Crop Production and Pest Control Research: West Lafayette, IN
 close



    Research

                    Research Projects
                                    Publications
                                    Collaborations
                                    News
                People

                    Staff Listing
                                    CareersSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Midwest Area West Lafayette, Indiana Crop Production and Pest Control 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
- Small Grains Viral Disease Laboratory
- Corn and Sorghum Fungal Disease Laboratory
- Host Plant Resistance to Insects Laboratory
- Wheat/Hessian fly Interactions Laboratory
- Small Grains Fungal Disease Laboratory
- Soybean Quality Improvement Laboratory
- Uniform Soybean Tests, Northern Region

Title:   Author  item
                                            Adhikari, Tikaitem
                                            Cavaletto, Jessicaitem
                                            DUBCOVSKY, JORGE - UNIV CALIF, DAVISitem
                                            GIECO, J - UNIV CALIF, DAVISitem
                                            SCHLATTER, A - IRB-INTA, BUENOS AIRES ARitem
                                            Goodwin, Stephen

                                                         - *Steve*
  Submitted to: Phytopathology
                                    Publication Type: Peer Reviewed Journal
                                    Publication Acceptance Date: 10/12/2004
                                    Publication  Date: 10/12/2004
                                    Citation: Adhikari, T., Cavaletto, J.R., Dubcovsky, J., Gieco, J., Schlatter, A.R., Goodwin, S.B. 2004. Molecular mapping of the stb4 gene for resistance to septoria tritici blotch in wheat. Phytopathology. 94:1198-1206.Interpretive Summary: Breeding wheat for resistance is the most effective means to control septoria tritici leaf blotch (STB), caused by the fungus Mycosphaerella graminicola (Septoria tritici is the name for its asexual stage).  At least eight genes that confer resistance in wheat to STB have been identified. Among them, the Stb4 gene from the wheat cultivar Tadinia showed resistance to M. graminicola at both seedling and adult plant stages.  However, no molecular markers linked to this gene are available and its map location remains unknown, which has limited its usefulness in plant-improvement programs.  To solve these problems, a mapping population derived from a cross between the resistant wheat cultivar Tadinia and a susceptible parent was evaluated for disease resistance and molecular mapping in the field and greenhouse.  Both the field and greenhouse results confirmed a single gene controlling the Stb4 resistance to M. graminicola.  Twelve molecular markers linked to the resistance gene were identified, the closest of which was a repetitive marker with a known map location.  Stb4 was mapped close to the center of wheat chromosome 7D, near the Stb5 gene for resistance to M. graminicola and very close to a cluster of genes for resistance to Russian wheat aphid.  This information will be of great interest to plant pathologists and geneticists, as it identifies a cluster of resistance genes with specificities to fungal and insect pests.  The molecular markers will allow the Stb4 gene to be utilized immediately to its maximum potential.  Plant breeders worldwide can use the molecular markers to select for resistant individuals instead of performing inoculations, which will facilitate combining Stb4 with other STB resistance genes into a single wheat cultivar for durable resistance to M. graminicola.
                                Technical Abstract: Breeding wheat for resistance is the most effective means to control septoria tritici leaf blotch (STB), caused by the ascomycete Mycosphaerella graminicola (anamorph Septoria tritici). At least eight genes that confer resistance in wheat to STB have been identified. Among them, the Stb4 locus from the wheat cultivar Tadinia showed resistance to M. graminicola at both seedling and adult plant stages. However, no attempt has been made to map the Stb4 locus in the wheat genome. A mapping population of 83 F10 recombinant-inbred lines (RILs) derived from a cross between the resistant cultivar Tadinia and the susceptible parent (Yecora Rojo x UC554) was evaluated for disease resistance and molecular mapping. The RILs were tested under high disease pressure in California and artificially inoculated with an Indiana tester isolate of M. graminicola in the greenhouse during 2000 and 2001. Both field and greenhouse phenotypic data segregated in a 1:1 ratio, confirming the single-gene model for control of Stb4 resistance to M. graminicola. Bulked segregant analysis was used to identify amplified fragment length polymorphism (AFLP) and microsatellite markers linked to the Stb4 gene. The AFLP marker 
EcoRI-ACTG/MseI-CAAA5 and microsatellite Xgwm111 were closely linked to the Stb4 locus in coupling at distances of 2.1 and 0.7 cM, respectively. A flanking marker, AFLP E-AGG/M-CAT10, was distal to the other tightly linked markers and was 4 cM from Stb4. Stb4 was mapped near the centromere on the short arm of wheat chromosome 7D, near a cluster of genes for resistance to Russian wheat aphid. The microsatellite marker Xgwm111 identified in this study will be useful in marker-assisted breeding for STB-resistant wheat.


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