2013 Annual Report
1a.Objectives (from AD-416):
(1) Collect, in Turkey, new pathogens of invasive weeds that are important in the U.S. and Turkey; (2) Determine the efficacy of the pathogens in infecting and damaging these weeds in the field in Turkey, and (3) Determine the host range of the pathogens among related non-target species.
1b.Approach (from AD-416):
New pathogens of invasive weeds in the U.S. and Turkey will be collected each year of this agreement. These pathogens will be isolated from diseased tissue either at FDWSRU or OMU or both. Studies on inoculation and infection efficacy of pathogens collected in Turkey in the past are currently ongoing in the containment laboratory at FDWSRU. Newly collected pathogens under this agreement will be studied in a like manner. Results of these studies will enable development of inoculation protocols that give maximum infection and disease development. Discovery of the best inoculation procedure and timing of inoculation to produce infected plants will enable instigation of epidemics in the field in Turkey. These protocols will be used for infection and host range studies in the field with the indigenous pathogen isolates from Turkey. These studies will be carried out simultaneously with inoculation and infection experiments.
Inoculum of pathogens collected in Turkey will be initially increased by our collaborator at OMU in Samsun, Turkey. The collaborator will inoculate host weeds to further increase inoculum for field tests. The collaborator will also locate fields infested with host weeds that can be used for our field tests. FDWSRU will supply the collaborator with seeds of some non-target test plants and seeds of other non-target test plants will be collected from Turkey.
Inoculation, monitoring, harvest, reisolation, and propagation of plants in and around OMU will not be problematic. Good facilities at OMU laboratories will help in accomplishing these activities. No hazardous procedures, materials, situations, or activities will be encountered. In short, successful infection, host range, epidemiology, and pathogen-spread studies in the native range of both the host and the pathogen are entirely feasible. Multiple successes, with different pathogens and hosts, within the anticipated three-year duration of the proposed project is very likely.
This is the final report for project 1920-22000-039-02S which will terminate on 09/14/2013. Diseases of invasive weeds in the U.S. were collected in Turkey through collaboration with Ondokuz Mayis University (OMU) in Samsun. Pathogens are being isolated from diseased tissue from each weed. Leaf spot diseases were found on Convolvulus arvensis (field bindweed) and Calystegia sepium (hedge bindweed). One pathogen, Phoma macrostoma var. macrostoma, isolated from field bindweed is a newly discovered pathogen on this weed. This pathogen from Turkey shows promise for biological control of field bindweed. Another pathogen, Stagonospora convolvuli, was also isolated from field bindweed and tested, separately and together with P. m. macrostoma, for damage to this weed. In all tests, S. convolvuli proved very damaging. Tests with this pathogen are proceeding in quarantine at USDA/ARS Foreign Disease-Weed Science Research Unit and in the field at OMU in Turkey. Collaborators from OMU are currently collecting, in Turkey, Canada thistle leaves diseased with the rust fungus Puccinia punctiformis to inoculate emerging rosettes of the weed in September, 2013. The objective of this test is to establish systemically diseased plants which will emerge in the spring of 2014. Tests in the U.S., Greece, New Zealand, and Russia have been successful in doing this, and these tests in Turkey, will be additional replications in an international experiment to demonstrate that systemic rust disease can be routinely established.