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
 Dairy Forage Research: Madison, WI
 close



    Research

                    Research Projects
                                    Publications
                                    Collaborations
                                    News
                People

                    Staff Listing
                                    CareersSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Midwest Area Madison, Wisconsin U.S. Dairy Forage Research Center Dairy Forage 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
                                            Riday, Heathcliffeitem
                                            JOHNSON, DAVID - Cal/west Seeds
  Submitted to: Molecular Breeding of Forage and Turf Conference
                                    Publication Type: Proceedings
                                    Publication Acceptance Date: 4/20/2012
                                    Publication  Date: N/A
                                    Citation: N/AInterpretive Summary:
                                Technical Abstract: Alfalfa (Medicago sativa L.) is a major forage legume.  Selfing (i.e. self-pollination) in alfalfa is possible, particularly in the absence of pollen from another genotype. Selfing has also been shown to occur in insect pollinated seed production fields. Reported selfing rates under field conditions range from 2% to 53%. By and large, alfalfa breeders have ignored selfing in their plant breeding programs except in breeding schemes requiring intentional selfing. Even modest selfing rates will significantly increase inbreeding depression, particularly in successive synthetic seed increase generations. Inbreeding depression due to selfing dwarfs inbreeding effects associated with narrow- versus broad-based synthetics. Prior to molecular markers, identifying selfed progeny in a standard alfalfa polycross or seed production field was almost impossible. In this study we present a SAS software program and simple DNA test utilizing SSR markers amplified in one or two PCR reactions that can identify selfed progeny in tetraploid polycrosses. The DNA test is demonstrated on a 15 parent autotetraploid alfalfa polycross pollinated with leafcutter bees (Megachile rotundata F.). In the demonstration polycross a 45% selfing rate was observed, consistent with previous studies.  Outcross and self progeny were phenotyped for biomass yield and the synthetic’s genetic load was estimated. Based on the synthetic’s genetic load and selfing rate we estimated a 7% reduction in biomass yield from the syn 1 to syn 3 generation. One way to mitigate this yield loss would be to actively select for reduced selfing. A large range in selfing rates were observed between genotypes suggesting that selection for this trait should be feasible.


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