Lactarius Hatsudake Research Articles

容器内でのクロマツ，クヌギへの共生菌の接種による二員培養

Several symbiotic mushroom fungi (Tricholoma caligatum, Tricholoma robustum, Lyophyllum shimejii, Rhizopogon rubescens and Lactarius hatsudake) were inoculated to in vitro cultured trees, Japanese black pine and Japanese red oak. The inoculation method was crucial for covering of fungi over the root of in vitro plantlets. Dipping the root in the blended liquid culture of fungi was better than setting the agar block of fungi culture on the root. We found the mantle formation of Rhizopogon rubescens and Lactarius hatsudake around the roots of Japanese black pine and Lyophyllum shimeji around those of Japanese red oak in vitro.

Concentrations of radiocesium and potassium in basidiomycetes collected in Japan

Concentrations of 137Cs, 134Cs and 40K in about 60 mushroom samples (fruit bodies of basidiomycetes) belonging to 25 species collected in Japan have been studied. The levels of 137Cs varied very widely, ranging from <3 to 1520 Bq kg −1 (dry wt), while those of 40K were relatively constant. Concentrations of 137Cs in common edible mushrooms of Japan such as Lentinus edodes, Flammulina velutipes, Pleurotus ostreatus and Pholiota nameko were low (normally < 50 Bq kg −1, dry wt). Concentrations of 134Cs in many samples were below the limit of detection (usually < 5 Bq kg −1, dry wt). The median concentrations of 137Cs and 40K were 41 (dry wt) and 1150 Bq kg −1 (dry wt), respectively. From the 137Cs/ 40K ratios it was found that cesium rather than potassium was selectively taken up from the soils fungi such as Suillus granulatus and Lactarius hatsudake. The 134Cs/ 137Cs ratios in mushrooms are related to the depth of the mycelium in the soil. The effective dose equivalent due to the dietary intake of radiocesium through mushrooms was estimated to be only 1.6 × 10 −7 Sv.