VIEW ARTICLE

Etiology

Reinvestigation of the Role of a Lactobacillus Associated with Leafhopper Vectors of Pierce’s Disease of Grapevines. A. H. Purcell, Department of Entomological Sciences, University of California, Berkeley, CA 94720; B. A. Latorre-Guzmán(2), C. I. Kado(3), A. C. Goheen(4), and T. A. Shalla(5). (2)(3)(4)(5)Department of Plant Pathology, University of California, Davis, CA 95616. Phytopathology 67:298-301. Accepted for publication 3 September 1976. Copyright © 1977 The American Phytopathological Society, 3340 Pilot Knob Road, St. Paul, MN 55121. All rights reserved.. DOI: 10.1094/Phyto-67-298.

Transmission of Pierce’s disease to healthy grapevines occurred only after its leafhopper vectors were first allowed to feed on diseased vines. Noninfective adult males and nymphs of Hordnia circellata or Draeculacephala minerva that were injected with or given access feeding to several cultures of a Lactobacillus sp. isolated from H. circellata that had transmitted the Pierce’s disease agent, did not transmit the disease to test plants. Infective and noninfective H. circellata, when surface-sterilized, triturated, and plated on medium 523 agar, produced isolates of this bacterium about equally. The bacterium was not recovered from D. minerva that had fed on grapevines with Pierce’s disease and was recovered only infrequently from D. minerva that had fed on broth cultures of the bacteria. These results contradict previous reports that this bacterium is the causal agent of Pierce’s disease.