Effect of electric impulse on sporocarp formation of ectomycorrhizal fungusLaccaria laccata in Japanese red pine plantation
We examined the effect of electric impulses on sporocarp formations of ectomycorrhizal fungus in a Japanese red pine (Pinus densiflora) plantation.Laccaria laccata was the dominant species in this study plantation. Spatial distribution concentrated in the electric impulse treatment zone, and recorded a markedly larger number of sporocarps compared with untreated control plots. The effect of electric impulses was also recognized onL. laccata fruiting with a mycorrhizal sapling in a pot. Sporocarp production ofL. laccata was strongly promoted by the electric impulse in experiments bothin vivo natural plantation stands andin vitro pot saplings. Our work indicates the possibility of enhancement of sporocarp production of the mycorrhizal fungi with electric impulses in the nursery and plantation.
Efficacy of ectomycorrhizal basidiomycetes on Japanese larch seedlings assessed by ergosterol assay.
Five fungal species, Suillus grevillei, Bole- tinus cavipes, Inocybe kobayasii, Lactarius porninsis and Gomphidius maculatus were examined for ergos- terol content during mycorrhizal formation. Ergos- terol assay was a suitable method for monitoring es- tablishment of 5 ectomycorrhizal fungi on roots. Er- gosterol contents were positively correlated to bio- mass of each of 5 ectomycorrhizal basidiomycetes growing on Melin-Norkrans medium, ranging 1.78- 2.36 iig mg-' dry mycelia. These fungi formed ecto- mycorrhizae with Japanese larch seedlings in contain- er-grown axenic culture. There were significant cor- relations between overall mycorrhizal density and seedling growth such as root length and shoot height at 6 mo. Mycorrhizal seedlings accumulated more mass in the root system and mycorrhizae compared with nonmycorrhizal seedlings.
An Internet-based Real-time Heavy Rainfall Display System
A new storm warning system, which can be accessed through the Internet and by cellular phones is described. At the time of a heavy rainfall for disaster prevention, it is important that every resident understand how heavy is that rainfall. A real-time heavy rainfall display system designed for all of Japan provides such information (http://www.disaster-i.net/rain/). In that system values for 1-hour precipitation, 24-hour accumulated precipitation, etc. are displayed at every observatory. Advantages are that not only the latest observations but differences from the historical highest records can be seen. Almost all information is displayed by characters so that users have easy access to the system even when the communication network is crowded. Access date for the six months after the system opened shows that the average daily number of accesses of the top page was 306, and the largest number 3078. The maximum number for daily access to all the pages was about 21,500. This is about 2% of the number obtained on the same day for a similar system operated by the Ministry of Land, Infrastructure and Transport (http://www.river.go.jp/).