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

Effects of Terpene on growth of Xylella fastidiosa

  • Author(s): Chang, Chung-Jan; Franklin, L.; Zhang, Ben-Li;
  • Abstract: Effects of TerpeneLN (TLN) and TerpeneAT (TAT) on growth of fifteen strains of Xylella fastidiosa (Xf) were investigated for possible use for control of diseases caused by Xf. TLN and TAT were tested at the concentrations of 3.3, 5, 10, and 20% for their effects on growth inhibition of 15 Xf strains. Tween 80 at 1 and 2% was tested for comparison. Each test plate of PW agar (100X15mm) was seeded with 105-107 CFU of an Xf strain. Then 0.1 mL of the proper concentration of the test chemical was pipetted onto a 13mm disk which was then placed in the center of the plate. All but one strain each from mulberry and oak grew well at 1% Tween 80. Zones of inhibition ranging from 1.1 to 3.1cm were recorded for all strains when 10% TLN or TAT was used. Some inhibition (0.1-0.4cm) or complete inhibition (5cm) (two grape strains) were recorded when 2% Tween 80 was tested. Complete inhibition was recorded for all 15 strains when 20% TLN was tested, while zones of inhibition (1.2-3.0cm) for five strains or complete inhibition for 10 strains were recorded when 20% TAT was tested.
  • Publication Date: Jun 2001
  • Journal: Phytopathology