Abstract
Agriculturally important grasses contain numerous diazotrophic bacteria, the interactions of which are speculated to have some other benefits to the host plants. In this study, we analyzed the effects of a bacterial endophyte, Azospirillum sp., on disease resistance in host rice plants. Rice plants (Oryza sativa cv. Nipponbare) were inoculated with Azospirillum sp. exhibited enhanced resistance against diseases caused by the virulent rice blast fungus Magnaporthe oryzae and by the virulent bacterial pathogen Xanthomonas oryzae. In Arabidopsis, plants (Col-0) were inoculated with Azospirillum sp. also exhibited enhanced resistance against virulent bacterial pathogen, Pseudomonas syringae pv. tomato DC3000. These results indicate the possibility that strain is able to induce disease resistance in rice and Arabidopsis. Furthermore, we studied the effect of colonization on the growth of Arabidopsis.
