Klebsiella oxytoca '10mkr7' stimulates Striga suicidal germination in Zea mays

Abstract

The Striga species are obligate root parasitic plants. Plant growth promoting rhizobacteria could enhance Striga suicidal germination. In screen-house studies we quantified the effect of bacterial inoculation with increasing maize plant density on the parasitic weed Striga hermonthica. The design used was a randomized complete block with a factorial arrangement (4 plant density levels, 2 S. hermonthica infestation levels, artificial and natural, and 2 isolate levels, with and without isolate). Interactions between bacteria and Striga count varied significantly (p=0.05). Seed germination differed significantly among plant densities from 6 to 8 WAP in the absence of bacteria. In bacterial inoculated pots significant differences were observed among plant densities from 5 WAP. Maize planted on soil inoculated with Klebsiella oxytoca‘10mkr7' had higher Striga counts at harvest for all plant densities. Significant variation was observed for interactions between bacteria and Striga. These findings suggest that Klebsiella oxytoca ‘10mkr7' is a plant growth
promoter and could stimulate Striga suicidal germination. Hence, there are good prospects for biological control of Striga using indigenous rhizosphere K. oxytoca ‘10mkr7'

Keywords: Maize; plant density; Klebsiella oxytoca; Striga hermonthica; suicidal germination

J. Trop. Microbiol. Biotechnol. Vol. 3 (2) 2007: pp. 13-19