|Press, Caroline - OREGON STATE UNIVERSITY|
|Kloepper, J. - AUBURN UNIVERSITY|
Submitted to: Phytopathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 1, 1998
Publication Date: N/A
Technical Abstract: Serratia marcescens strain 90-166 induces systemic resistance of cucumber to several pathogens and at least two insect pests. The mechanisms employed by this strain to cause ISR are currently under investigation. Previous results indicated that disease suppression by strain 90-166 is inversely related to the availability of iron in the rhizosphere. Production of a catechol siderophore by strain 90-166 appears to be involved in ISR and a mini-Tn5 mutant (90-166-2882) deficient in catechol production does not cause ISR. Sequence analysis of the genetic region surrounding the insertion site indicated a high degree of homology to genes encoding isochorismate synthase (fbsC, entC, and dhbC) and enterobactin biosynthesis (entA). These results suggest that catechol production is disrupted in 90- 166-2882. Marker exchange mutants are being evaluated for lack of catechol production and ISR capacity. The relationship between catechol production and ISR will be discussed.