Fine-scale initiation of non-native Robinia pseudoacacia riparian forests along the Chikumagawa River in central Japan

International audience(Loi n° 91-650 du 9 juill. 1991, art. 47

Appendix A. Photographs of vegetation patches in a volcanic desert on Mount Fuji, Japan.

Photographs of vegetation patches in a volcanic desert on Mount Fuji, Japan

Spatial Distribution of Ectomycorrhizae and Their Morphological Features in a Plantation of Abies firma

モミ造林地において，外生菌根菌の現状把握のため，子実体の空間分布と外生菌根の形態的特徴について調査した。設置した方形区（15m×10m）の中には，22種の子実体が発生し，そのうち外生菌根菌と考えられるものは6種であった。もっとも発生量が多かったのはアカモミタケで，概して散らばった発生パターンを示し，明確なシロは形成しなかった。また，ほかの子実体がまとまって発生した場所には，アカモミタケの発生がなかった。試験地で採取した外生菌根には，数種類の異なる形態的特徴を持つものが確認できた。アカモミタケの外生菌根断面をSEMで観察したところ，菌鞘は2つの層に分けられ，それぞれ異なった構造を持つことが分かった。ハルティヒネットは，根端付近の未熟な皮層より後方で，老化による分解が起こるよりも前方の，ある一定範囲の皮層にのみ発達する構造であることが確認された。また，この部分の皮層細胞は放射方向に直径が肥大していた。In order to clarify the behavior of ectomycorrhizae in an Abies firma plantation, spatial patterns of sporophores and the morphological features of ectomycorrhizae were studied. In a quadrat (15m×10m) in the Abies forest, the sporophores of 22 species, including 6 mycorrhizal fungi, were found. Sporophores of an ectomycorrhizal fungus, Lactarius laeticolorus, spread in a dispersed pattern and fungal colonies (\u27Shiro\u27) did not appear. The sporophores of this fungus were not found in clumps of sporophores of the other fungi. As to the vertical distribution of ectomycorrhizae, they were concentrated in the upper 20cm layer of the soil. The ectomycorrhizae of L. laeticolorus had a well developed fungal sheath, which was divided into two layers morphologically. This mycorrhiza also had a Hartig net behind the growing apex and in advance of the region where the cortex cells begin to deteriorate as the root matures. Cortex cells in the Hartig net region had greater radial diameters