Title: Impact of Irrigation on Populations of Antibiotic-Producing Pseudomonas Spp. in Rhizosphere of Wheat Authors
Submitted to: Microbial Ecology International Symposium
Publication Type: Abstract Only
Publication Acceptance Date: June 20, 2010
Publication Date: August 20, 2010
Citation: Mavrodi, O., Mavrodi, D., Parejko, J., Thomashow, L.S., Weller, D.M. IMPACT OF IRRIGATION ON POPULATIONS OF ANTIBIOTIC-PRODUCING PSEUDOMONAS SPP. IN RHIZOSPHERE OF WHEAT. Microbial Ecology International Symposium, 22-27, August, 2010, Seattle, WA. Technical Abstract: This work studied the impact of irrigation on seasonal dynamics of populations of phenazine (Phz+) and 2,4-diacetylphloroglucinol (Phl+) Pseudomonas spp. in the rhizosphere of wheat grown in the low-precipitation zone (<400 mm) of the Columbia Plateau of the Inland Pacific Northwest, WA. Population sizes and plant colonization frequencies of Phz+ and Phl+ Pseudomonas spp. were determined in winter wheat collected during March – June, 2008 from selected commercial dryland and irrigated fields near towns of Ritzville and Lind, WA. Only Phz+ bacteria were detected on dryland winter wheat grown with populations ranging from log 5.2 to 7.3 CFU g root-1 and rhizosphere colonization frequencies of 63 to 100%. Similar population sizes of both Phz+ and Phl+ Pseudomonas spp. were recovered from wheat grown under irrigation with 88-100% plants colonized by Phl+ bacteria and only 13 - 38% of plants harboring Phz+ bacteria. These findings were in perfect agreement with results of a second sampling that covered 16 dryland and irrigated fields in the Ritzville area.