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Tricholoma matsutake, a basidiomycete, forms ectomycorrhizas with Pinus densifloraas the host tree. Its fruiting body, “matsutake” in Japanese, is an edible and highly prized mushroom, and it grows in a circle called a fairy ring. Beneath the fairy ring of T. matsutake, a whitish mycelium-soil aggregated zone, called “shiro” in Japanese, develops. The front of the shiro, an active mycorrhizal zone, functions to gather nutrients from the soil and roots to nourish the fairy ring. Bacteria and sporulating fungi decrease from the shiro front, whereas they increase inside and outside the shiro front. Ohara demonstrated that the shiro front exhibited antimicrobial activity, but the antimicrobial substance has remained unidentified for 50 years. We have identified the antimicrobial substance as the (oxalato)aluminate complex, known as a reaction product of oxalic acid and aluminum phosphate to release soluble phosphorus. The complex protects the shiro from micro-organisms, and contributes to its development.

Two distinct electroantennographycally active (EAG-active) components, A and B, and a weakly active component C were found in a solvent extract from virgin females of the Ishigaki strain of the tussock moth, Orgyia postica(Walker). Components A, B, and C were found in the extract of the females at 4.0, 0.5, and 4.0 ng/female respectively. Components A, B, and C were identified as (6Z,9Z,11S,12S)-11,12-epoxyhenicosa-6,9-diene [(11S,12S)-1: posticlure], (6Z)-henicos-6-en-11-one (2), and (6Z,9Z)-henicosa-6,9-diene (3), respectively. Component B was absent in the extract from the Okinawa strain, in which components A and C were present at 2.0 and 1.5 ng/female respectively. (11S,12S)-1and the racemic mixture showed attractiveness for both the Okinawa and Ishigaki strains, whereas (11R,12R)-1did not. The addition of 2significantly reduced the trap catches with (11S,12S)-1on the Okinawa strain which lacked 2, while there was no significant inhibitory effect on the Ishigaki strain. The addition of 3to (11S,12S)-1did not significantly affect trap catches at Ishigaki or Okinawa. This confirmed that the attractant pheromone of O. posticaof the Ishigaki strain is also (11S,12S)-1.

We quantified the cyanamide content of young leaves of nine Viciaspecies, Lens culinaris, and Robinia pseudo-acaciausing a modified analytical procedure that made it possible to measure the cyanamide content of a single leaf. Recent molecular phylogenetic analysis suggests that cyanamide is present in V. benghalensis, which is placed in a monophyletic group with cyanamide-biosynthesizing plants, V. villosaand V. cracca; this suggestion was verified.