New Technique Improves Sensitivity of PCR Pathogen Detection

A new procedure devised by U.S. Department of Agriculture (USDA) scientists and colleagues can improve polymerase chain reaction (PCR)-based methods of detecting plant disease organisms.

Bio-PCR works best with fast-growing bacteria such as Ralstonia solanacearum, which causes bacterial wilt of potato and tomato, and Acidovorax avenae, which causes bacterial fruit blotch of watermelon.

However, Bio-PCR also improves detection of slow-growing pathogens such as Xylella fastidiosa, responsible for Pierce's disease of grapes and leaf scorch of shade trees.

In studies with X. fastidiosa, Bio-PCR detected the bacterium in 90 percent of infected grape samples compared to 13 percent with conventional PCR methods.