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Tricholoma matsutake, a basidiomycete, forms ectomycorrhizas withPinus 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 ofT. 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. “Antimicrobial activity of the matsutake shiro” for left figure.“The antimicrobial substance, the (oxalato)aluminate complex, from the matsutake shiro” for right figure. [ABSTRACT FROM PUBLISHER]

Physiological and biochemical studies on the leaf apoplast have been facilitated by the use of the infiltration–centrifugation technique to collect intercellular washing fluid (IWF). However, this technique has been difficult to implement in rice (Oryza sativa L.) for various reasons. We compared the collection efficiency of leaf IWF between two types of rice varieties (Indica and Japonica), as well as between rice and other species (spinach, snap bean and wheat). Although the extraction of IWF in most species took only 2–3 min, it took up to 35 min in rice. The difficulty in infiltration with rice was ascribed to the small stomatal aperture and hydrophobicity of the leaves. In this study, we have established an improved method for collecting IWF and determining the apoplastic air and water volumes in rice leaves. We have shortened the infiltration time to 8 min via the following improvements: (i) infiltration under outdoor shade in the daytime to prevent stomatal closure and a rise in temperature of the infiltration medium; (ii) soaking of leaves in a surfactant solution to decrease the leaf hydrophobicity; and (iii) continuous pressurization using a sealant injector to facilitate the infiltration. The rapid collection of IWF achieved using this technique will facilitate study of the leaf apoplast in rice. [ABSTRACT FROM AUTHOR]

Focuses on sex pheromone and related compounds in the Ishigaki and Okinawa strains of the tussock moth Orgyia postica (Walker). Discovery of two distinct electroantennographycally active components, A and B, and a weakly active component C in a solvent extract from virgin females of the Ishigaki strain of the tussock moth; Finding of components A, B, and C in the extract of the females at 4.0, 0.5, and 4.0 ng/female respectively; Confirmation that the attractant pheromone of O. postica of the Ishigaki strain is also (11S,12S)-1; Discussion of the attractiveness of the components to the males on both Japanese islands in the context of the activity and possible evolution of pheromonal polymorphism in the species.

The article presents a simple analytical method for the quantification of cyanamide in plants. It further analyzes the cyanamide contents of the leaves, stems, cotyledons and roots of young seedlings of V. villosa and of the leaves of other Vicia species, Lens culinaris and Robinia pseudoacacia. It reports three advantages of this method over traditional ones which include requirement of less plant material, stable mass chromatogram and reduced risk of enzymatic activity.

The article presents a study which investigated the distribution of cyanamide in the plant kingdom using a direct quantitative determination method to detect and measure cyanamide by stable isotope dilution gas chromatography-mass spectrometry. The method proved to be a robust way to quantify cyanamide contents in the extracts of 101 species of herbaceous plants.