Abstract
Effects of rhizobial symbiosis on Orobanche aegyptiaca parasitism to Lotus japonicus were studied. Approximately 30% of the parasite attached onto the host root formed tubercles, and root primordia developed from the tubercles. Concurrent inoculation of Mesorhizobium loti doubled the number of tubercles, suggesting some positive effects of rhizobial symbiosis on the parasite invasion. Inoculation of the rhizobium three weeks before attachment of the parasite did not affect the number of tubercles. However, the tubercles turned brown, and root development of the parasite delayed significantly, suggesting the negative effects of the symbiosis on the parasite growth.
