Abstract

Inhibition of weed germination by mixed microbial strains was investigated in pots under conditions similar to paddy soil. Mixed microbial strains were comprised of four lactic acid bacteria and four saccharomycetes. Twenty seeds of Echinochloa crusgalli, Aeschynomene indica, Digitaria sanguinalis and Amaranthus retroflexus were, respectively, sown in petri dishes and each petri dish was treated with the microbial strain solution at six rates in order to assess its effect on germination. Results showed that the germination of these weeds was effectively inhibited by application of mixed microbial strains. To evaluate the weed control effect, 20 seeds of E. crus-galli, M. vaginalis, L. prostrata, S. juncoides and A. indica were successively sown in pots under conditions similar to paddy soil. Each pot contained 10 cm-deep paddy soil clean of surface weeds, and mixed microbial strains were applied to the pots two weeks after sowing. It was found that at 80 L/ha or higher rates mixed microbial strains could simultaneously and effectively control the above five weeds in pots under conditions similar to paddy soil. In conclusion, the present study results could serve as basic information for the development of new environmentally friendly microbial herbicides in paddy fields.