Skip to main content
ARS Home » Research » Publications at this Location » Publication #75149
Title: THE USE OF RNA FINGERPRINTING METHODS BASED UPON AFLP AND RAPD TECHNOLOGY TO IDENTIFY GENETIC MARKERS LINKED TO METALAXYL RESISTANCE IN PHYTOPHTHORA INFESTANS

Author
item Scott, David
item Deahl, Kenneth

Submitted to: Current Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/24/1997
Publication Date: N/A
Citation: N/A

Interpretive Summary: The inability to identify cultivars with high levels of stable resistance against Phytophthora infestans has resulted in the use of protectant fungicides (Metalaxyl) to suppress late blight disease. Metalaxyl provides the disease management specialist with a potentially more effective tool to control late blight disease. However, P. infestans isolates that are resistant to metalaxyl have been identified. RNA fingerprinting is a powerful technique for the simultaneously identification of genes that are up- or down-regulated under different conditions. The procedure is based upon PCR amplification of mRNA of cells or tissue, using a short 5' arbitrary primer, an oligo (dT0-NN3' primer. Differentially gene expression are then visualized by autoradiography or by a non-radioactive staining method after electrophoretic separation. RNA fingerprinting was used to identify genetic markers linked to metalaxyl resistance in P. infestans. The timely identification of fungicide resistant genotypes within a field or seed lot should aid those involved in disease management to develop effective containment strategies.

Technical Abstract: Information regarding the genetic makeup of isolates of the oomycetus fungus Phytophthora infestans that are resistant to the fungicide Metalaxyl versus those that are sensitive has been extremely limited. We report the use of RNA fingerprinting based upon Random Amplified Polymorphic DNA (RAPD) and Amplified Fragment Length Polymorphisms (AFLP) technology to identify genetic markers linked to metalaxyl resistance. Using these procedures we identified amplicons that represented genes that were either up or down regulated in the presence of metalaxyl. The ability to identify metalaxyl resistance isolates of P. infestans, which causes potato late blight disease, could prove to be invaluable to potato growers when decisions in disease management and prevention are continent upon genotypic traits.