The objective of the current study was to elucidate the quantity and chemical composition of chemoattractants and antimicrobials in the extract of .Carex kobomugi Ohwi. (C. kobomugi) roots.

Mature C. kobomugi was collected in October 2010 from Hasaki coast. The roots were extracted with 70% methanol and evaporated in vacuo. Dried residue was dissolved in water and separated with ethyl acetate. To evaluate bacterial chemotaxis toward ethyl acetate phase, water phase and the mixture, the capillary chemotaxis assay was applied to three strains: Bacillus sp. (BS), Pseudomonas fluoresens (PF), and Rhizobium sp. (RS). To evaluate antifungal activity toward each sample, TLC bioautography using Cladosporium herbarum was conducted.

Bacterial positive chemotaxes were shown in all samples and the highest activity was confirmed in the mixture of each phase. In the ethyl acetate phase, several antifungal compounds were observed. In addition, the highest degree of chemotactic response to the mixture was shown in BS strain. These results suggested that PGPB might exhibit chemotaxis toward at least 2 factors from the root extract, and be tolerant to several antifungals. We will discuss the C. kobomugi roots-PGPB interaction mediated by chemotactic　and antifungal compounds in our presentation.