Frequency, Diversity, and Activity of 2,4-Diacetylphloroglucinol-Producing Fluorescent Pseudomonas spp. in Dutch Take-all Decline Soils

• DOI: 10.1094/phyto.2003.93.1.54
• Publication Date: 2007-05-11T11:17:19Z
• Authors: Jorge T. de Souza; David M. Weller; Jos M. Raaijmakers
• Keywords: 0301 basic medicine; 2. Zero hunger; suppressive soils; biological-control; fungus; gaeumannomyces-graminis; graminis var tritici; 03 medical and health sciences; ecological fitness; wheat roots; metabolite 2,4-diacetylphloroglucinol; rhizosphere; antibiotic biosynthesis

ABSTRACT Natural suppressiveness of soils to take-all disease wheat, referred as decline (TAD), occurs worldwide. It has been postulated that different microbial genera and mechanisms are responsible for TAD in from geographical regions. In growth chamber experiments, we demonstrated fluorescent Pseudomonas spp. produce the antibiotic 2,4-diacetylphloroglucinol (2,4-DAPG) play a key role natural two Dutch soils. First, 2,4-DAPG-producing were present on roots wheat grown both at densities or above threshold density required control wheat; complementary conducive soil, population below this level. Second, introduction strain SSB17, representative dominant geno-typic group found soils, into soil similar indigenous 2,4-DAPG producers provided observed soil. Third, mutant SSB17 deficient production was not able indicating is determinant suppression. These results show addition physicochemically Washington State, also component Furthermore, it first time since initial studies Gerlagh (1968) least part microorganisms operate identified. Although quantitatively similar, genotypic composition varied between State.