ARS | Publication request: EXPLOITING SOIL SUPPRESSIVENESS AND BENEFICIAL RHIZOBACTERIA FOR STRIGA HERMONTHICA CONTROL IN AFRICA

Submitted to: American Phytopathological Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: July 1, 2004
Publication Date: July 1, 2004
Citation: Ahonsi, M.O., Berner, D.K., Emechebe, A.M., Lagoke, S.T. 2004. Exploiting soil suppressiveness and beneficial rhizobacteria for striga hermonthica control in africa. Phytopathology 93:S3.

Technical Abstract: Striga hermonthica (Del.) Benth. (SH) is a serious constraint to cereal production in Africa. Effects of soybean-maize rotation, N, P fertilizers and ALS-herbicide use on natural soil suppressiveness to SH in maize were evaluated. Fluorescent pseudomonads (GSP) that suppress SH seed germination were selected from suppressive soils and tested for ability to control SH in maize. Potentials of ethylene-producing pseudomonds (EP) in combination with N2-fixing bradyrhizobia as supplements to maize rotation with N2-fixing legumes, selected for suicidal germination of SH seeds, were evaluated. Results showed that soil suppressiveness to SH is biotic and soil treatments that increased fertility, including preceding soybean crop, application of P to preceding soybean crop, and N to current maize crop enhanced suppressiveness, while ALS-herbicides, especially imazaquin, was detrimental to suppressiveness. Six of 15 GSP reduced SH counts and increased maize yield. Reduction in SH parasitism in maize preceded by a cowpea or soybean crop was enhanced when the crop was co-inoculated with EP and bradyrhizobial strains. A SH control approach combining selected legumes fertilized with P and co-inoculated with EP and bradyrhizobia in rotation with a maize crop inoculated with GSP strains and fertilized with N is suggested.