|MOLAR, R. ALLENDE|
Submitted to: APS Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 5/20/2004
Publication Date: 7/20/2004
Citation: Molar, R., Landa, B.B., Weller, D.M. 2004. Long-term survival of different genotypes of 2,4-diacetylphloroglucinol (dapg)-producing pseudomonas fluorescens in soil. APS Annual Meeting. Phytopathology 94:S4.
Technical Abstract: DAPG-producing P. fluorescens are often enriched in soils that have undergone pea or wheat monoculture. Seventeen genotypes (A-Q) of such strains have been distinguished by repetitive sequence-based-polymerase chain reaction (rep-PCR); some of which are exceptionally aggressive root colonizers. In a greenhouse experiment, the long-term survival in soil of strains representative of genotypes A, B, D, L and K was tested. Soils inoculated with bacteria at 104 CFU/g of soil were sown to wheat for 10 successive cycles of 3 weeks each and then were stored dry at room temperature. After one year, the soils were again planted with wheat and root colonization by the bacteria evaluated during five three-week growth cycles. Strains F113 (K) and L5.1-96 (D) were detected on the roots in all five cycles indicating their ability to survive in soil over a long period of time and then rebound in population size when wheat is again grown. L51-96 (D) was the most persistent strain and reached population densities of up to 107 CFU/g of root. Strains of genotypes A, B and L were not detected when wheat was sown in the stored soils