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
 Crops Pathology and Genetics Research: Davis, CA
 close



    Research

                    Research Projects
                                    Publications
                                    Collaborations
                                    News
                People

                    Staff Listing
                                    Careers


        


                    Outreach Events
                        UC Davis Picnic Day
                                    Kinders go to College
                                    STEM Girls
                                    Future Scientist Program
                                    Agriculture Future of America
                                    Wallace-Carver Fellowship
                                    Young Scholars Program
                                    Annual Awards Banquet
                    About Us
                        About Us
                                    Our Mission
                                    Principal InvestigatorsSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Pacific West Area Davis, California Crops Pathology and Genetics 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
- Etiology and Biology of Tree Crop Diseases
- Rice Genetics
- Sustainable Floriculture
- Sustainable Viticulture

Title:   Author  item
                                            Sudarshana, Mysore
  Submitted to: Trade Journal Publication
                                    Publication Type: Trade Journal
                                    Publication Acceptance Date: 5/1/2011
                                    Publication  Date: 5/1/2011
                                    Citation: Sudarshana, M.R. 2011. Almond Brownline Disease. Trade Journal Publication. 17:26-35.Interpretive Summary:
                                Technical Abstract: A recent outbreak of almond brownline that occurred in Sutter County in 2008, provided an opportunity to investigate
on the nature of the pathogen associated with the disease. A grant
support was provided by the California Almond Research Board and the Tree Fruits & Nuts and Grapevines Advisory Board in the California Department of Food and Agriculture to conduct these
investigations and develop a molecular diagnostic assay for adoption by routine testing by private and public laboratories.
Amplifi cation of ribosomal DNA sequences from nucleic acid extracts from diseased almond leaves and subsequent
sequence analysis established association of a phytoplasma in almond trees with brown line disease. Genetically this region is of almond brown line phytoplasma is almost indistinguishable
from the ribosomal DNA sequences of phytoplasmas causingpeach yellow leafroll and pear decline diseases. However, examination of the chromosomal region distal to the ribosomal DNA region has not supported this notion and further work is in progress to establish the true identity of the phytoplasma which is essential to develop specific and sensitive molecular tools to identify bud wood sources free from brown line phytoplasma. Currently, a real-time quantitative PCR assay has been optimized for the detection of almond brown line phytoplasma at the USDA-ARS laboratory in Davis.
In nature, phytoplasmas are generally transmitted when bud wood is obtained from infected trees. The trees can also become infected when insect vectors carrying phytoplasma make a transient visit to almond trees or peach rootstocks and hence is generally isolated. In the event of a disease incidence, because of the lethal nature of disease in almonds on plum rootstock, the disease is self eliminating in trees on plum rootstock. Nurseries in California generally maintain almond mother trees on plum rootstock to recognize brown line phytoplasma and thus prevent distribution of trees with phytoplasma infections. Almond brown line disease is unlikely to become a major problem for almond production in California. If trees in young orchards happened to show brown line disease, it is best to remove the diseased trees and replant immediately. Horizontal spread of the disease has not been seen so far in diseased orchards and this is likely due to almond trees not being a good host for the insect vector that transmits the phytoplasma.


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