Pierce's Disease
Research Updates


What is Pierce's Disease?

Pierce's Disease is a bacterial infection, which is spread by bugs that feed on grapevines, particularly the "glassy winged sharpshooter." Grapevines that become infected with PD can quickly become sick and die.

glassy-winged sharpshooter

Interaction of Xylella fastidiosa with different varieties of Nicotiana tabacum: A comparison of colonization patterns

  • Author(s): Alves, E.; Kitajima, Elliot; Leite, Breno; Pascholati, S.;
  • Abstract: After the indication of Nicotiana spp. as an experimental host for Xylella fastidiosa (Xf), it became essential to understand how the interaction evolves and how investigational conditions alter symptomatology. Varieties TNN, Havana and RP1 had their symptoms monitored and correlated with the presence of bacteria inside leaf petiole vessels. Scanning electron microscopy and image analysis were used as tools for comparisons. The colonization efficiency was established by calculating the ratio between colony forming units per gram and percentage of colonized vessels. No statistical differences were found. We also observed that leaf symptoms could be reversed with ammonium sulfate applied to the substrate where plants were growing. In addition, pruning was effective in delaying symptom development. These results show that: colonization patterns were similar in tobacco varieties, fertilization may affect X. f. symptom expression and pruning may be used as an aid to diminish X. f. advance.
  • Publication Date: Jun 2003
  • Journal: Phytopathology