Submitted to: Phytopathology
Publication Type: Abstract Only
Publication Acceptance Date: 3/15/2004
Publication Date: 6/1/2004
Citation: Bruckart, W.L., Luster, D.G., Woods, .D. 2004. Status of puccinia jaceae in 2004 biological control of yellow starthistle in california. Phytopathology. 94:S12.
Technical Abstract: Yellow starthistle (YST, Centaurea solstitialis), an invasive weed infesting 5.8 million hectares in California, is a target of classical biological control. Development of Puccinia jaceae, an host specific rust fungus, has been pursued to complement insect agents already in place. Following an extensive risk analysis (65 species of plants, 10 families), release of a Turkish isolate of P. jaceae into California was approved on April 4, 2003 (PPQ 526 Permit No. 47497), and the first field inoculation of YST was made in North America outside of containment on July 9, 2003 in Napa County, California. Infection in the field was confirmed on July 30, 2003, and included both uredinia and telia. Since the release, conditions for spread in the field were unfavorable in 2003, but inoculum was increased in a CDFA greenhouse in Sacramento, CA. Plans are in place to monitor infection and spread of the fungus as well as to make additional releases in CA, pending extension and expansion of the permit. Events pertinent to biological control of YST in 2004 will be presented.