Skip to main content
ARS Home » Midwest Area » Columbia, Missouri » Cropping Systems and Water Quality Research » Research » Publications at this Location » Publication #160231
Title: HOST RANGE OF DELETERIOUS RHIZOBACTERIA FOR BIOLOGICAL CONTROL OF WEEDS OF CROPPING SYSTEMS IN AUSTRALIA AND SOUTH KOREA

Author
item PELTZER, SALLY - W AUSTRALIA DEPT AGRIC
item LEE, SANG-BOK - RDA, SOUTH KOREA
item KREMER, ROBERT

Submitted to: Weed Science Society of America Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 1/26/2004
Publication Date: 2/9/2004
Citation: Peltzer, S.C., Lee, S.B., Kremer, R.J., 2004. Host range of deleterious rhizobacteria for biological control of weeds of cropping systems in Australia and South Korea [abstract] [CD-ROM]. Weed Science Society of America. No. 76

Interpretive Summary:

Technical Abstract: Deleterious rhizobacteria (DRB) as biocontrol agents for weeds have received considerable attention in developing alternative weed management for reducing herbicide use and intensive tillage. The specificity of growth-suppressive rhizobacteria must be determined on a wide range of plant species prior to widespread release for use in crop production. Selected rhizobacteria cultured from Missouri, U.S.A. soils capable of suppressing seedling growth of selected weeds of U.S.A. cropping systems were evaluated for their effects on weeds and representative crops of Australia and South Korea. In agar plate assays, 3 of 4 DRB isolates reduced root growth of all crop cultivars and weed species from Australia; all DRB isolates reduced root growth of barnyardgrass (Echinochloa crus-galli) from Korea and 3 of 4 isolates reduced rice root growth. DRB assayed in a hydroponics system showed reduced effects of DRB on crop species from Australia but significantly reduced root growth of rice cv. Nongan from Korea. Rat's tail fescue (Vulpia myuros), soft brome (Bromus hordaceus), and barnyardgrass were inhibited by one or more DRB. In plant-soil bioassays, only rat's tail fescue, ripgut brome (Bromus diandrus) and barnyardgrass growth were significantly inhibited by one or more DRB; canola (Brassica napus cv. Surpass 501) from Australia was the only crop with suppressed growth. Based on the more rigorous plant-soil assays, DRB effective on U.S. weeds may hold promise for biocontrol of weeds only where silvergrass or ripgut brome are problem weeds in cereal-producing regions of Australia and for biocontrol of barnyardgrass in certain rice systems in Korea. This research suggests a need for selecting DRB in Australian and Korean environments to improve efficacy and broaden the host range of biocontrol.