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Retinal prostheses are promising techniques to restore eyesight sense for visually impaired people. However, some conventional retinal prostheses require external cameras, and the eyeball direction is different from the view direction. Moreover, some also require a wired connection between inside and outside of the body, and the quality of life (QOL) is seriously impaired. In this article, we have developed a retinal prosthesis using thin-film devices on a transparent substrate and wireless power transfer. The outstanding advantages are: thin-film photo-transistors are integrated to make the eyeball and view directions the same, a transparent substrate is employed to achieve epiretinal implantation, and wireless power transfer is adopted to ensure the QOL. Particularly in this article, a pig eyeball experiment is executed. It is found that the stimulating current is an appropriate value, and the oscillating frequency is dependent on the light illumination. From these results, it is concluded that the correct operation necessary for a retinal prosthesis as an implanted organ is confirmed.

The morphology of 18 and seven species of fungi isolated from spoiled bean sprouts of Vigna spp. and soybean in Japan were respectively described, and DNA barcode markers of most isolates were sequenced to confirm the morphological identification. Fifteen and five species were isolated for the first time from Vigna spp. and soybean sprouts, including their ingredient grains, respectively. Globisporangium ultimum var. ultimum was newly recorded from the mung bean and most isolated fungi seemed to originate from the grains. Approximately 70% of isolates are recognized as plant pathogens and at least 14 species are known to be seed-borne. Inoculation experiments with representative strains of each species are needed to estimate the risks to bean sprout production and crop protection. Some strains of Fusarium graminearum isolated from the soybean were already reported as producing high concentrations of deoxynivalenol. Aspergillus flavus, which was found in mung bean sprouts, is a well-known aflatoxin producer. The ingredient grains should be imported after complete sterilization to avoid hazards; not only to bean sprout production but to human health. The effects of previously used sterilization techniques should be re-examined with the strains of various fungi isolated in this study to make them more practical. Discipline: Food Additional key words: black matpe, fungal carrier, identification, mung bean, soybean

A database of plant diseases reported in Japan and a Web-based data-retrieval system to search for information stored in the database have been developed. The retrieval system is linked with the database on microorganism genetic resources registered in the Genebank Project of the National Institute of Agrobiological Sciences (the NIAS Genebank), which provides access to detailed genetic information on strains of these microorganisms. The NIAS Genebank manages the registration of so-called “passport” data for these genetic resources and controls their storage to make samples available to researchers worldwide. Data management software has been developed to register the receipt, storage, testing, and multiplication of these genetic resources. Search software has also been developed to seek suitable genetic resources based on several search criteria to facilitate their distribution from the stocks stored in the NIAS Genebank. DNA sequence data for the D1/D2, 18S, and internally transcribed spacer ITS (ITS1-5.8S-ITS2) regions of rDNA and for the coding region of the β-tubulin gene for many of the conserved microorganisms can be accessed from the NIAS Genebank Web site. The database on Japanese plant diseases and the NIAS Genebank search system are expected to become increasingly useful tools for research and education related to microorganisms and their genetic data, as well as for improving plant protection and food security.

The National Institute of Agrobiological Sciences (NIAS) is implementing the NIAS Genebank Project for conservation and promotion of agrobiological genetic resources to contribute to the development and utilization of agriculture and agricultural products. The project's databases (NIASGBdb; http://www.gene.affrc.go.jp/databases_en.php) consist of a genetic resource database and a plant diseases database, linked by a web retrieval database. The genetic resources database has plant and microorganism search systems to provide information on research materials, including passport and evaluation data for genetic resources with the desired properties. To facilitate genetic diversity research, several NIAS Core Collections have been developed. The NIAS Rice (Oryza sativa) Core Collection of Japanese Landraces contains information on simple sequence repeat (SSR) polymorphisms. SSR marker information for azuki bean (Vigna angularis) and black gram (V. mungo) and DNA sequence data from some selected Japanese strains of the genus Fusarium are also available. A database of plant diseases in Japan has been developed based on the listing of common names of plant diseases compiled by the Phytopathological Society of Japan. Relevant plant and microorganism genetic resources are associated with the plant disease names by the web retrieval database and can be obtained from the NIAS Genebank for research or educational purposes.

Restriction landmark genome scanning (RLGS) is a high-speed genome analysis method to detect DNA polymorphism, and is suitable to develop useful DNA markers for cultivar-discrimination of agricultural plants. The mat-rush, Juncus effusus is a vegetatively propagated crop that has been cultivated for over 500 years in Japan as the material of "tatami-omote," a surface of Japanese conventional mats. In recent years, Japanese mat-rush cultivars are grown in foreign countries and reimported to Japan in violation of the Seeds and Seedlings Law, economically damaging domestic production. The largest problem of illegal mat-rush reimportation has been with cv. Hinomidori. We developed a cultivar-discrimination DNA marker of mat-rush using RLGS, and detected the RLGS spot markers that didn't exist specifically in Hinomidori. The spot marker can be used with the RLGS method to identify Hinomidori accurately among cultivars.

In the central bank of the microorganisms section in the Ministry of Agriculture, Forestry and Fisheries (MAFF) Genebank in Tsukuba, 14,836 strains of fungi, bacteria, yeasts and others are preserved by various methods including cryopreservation and freeze-drying. To evaluate preservation techniques for these microorganisms, the viability of the preserved microorganisms was examined at regular intervals. Almost all tested strains, except for 5 strains out of 2,334 strains, of yeasts, bacteria and Actinomycetes were preserved well in freeze-dried form, indicating that freeze-drying is suitable for their preservation. As for fungi and Oomycetes, 6,578 strains out of 6,681 tested strains (98.5%) and 264 (63.8%) of 414, respectively, survived one-year preservation in the vapor phase of liquid nitrogen. The details on survival of the preserved fungal strains were as follows: 99.0% (1,107 strains/1,118 tested strains) survival in Ascomycota, 96.1% (1,552/1,615) in Basidiomycota, 98.6% (73/74) in Zygomycota, and 99.3% (3,846/3,874) in anamorphic fungi. Thus, cryopreservation is excellent for preservation of most fungus strains, but is not suitable for preservation of many Oomycetous strains.

Glomerella cingulata (Stoneman) Spaulding et Schrenk (anamorph: Colletotrichum gloeosporioides (Penzig) Penzig et Saccardo) has been known as the pathogen of ripe rot of grapevine (Vitis vinifera L.). In addition to this fungus, another Colletotrichum species was isolated from fruits of grape cultivar ‘Sekirei’ with ripe rot in Shimane Prefecture in 1994. Colonies of the isolate on potato dextrose agar (PDA) were reddish to pale brown. Its conidia on PDA were one-celled, hyaline, ellipsoid to fusiform with acute ends and 12-17×4-5μm. Appressoria formed on potato carrot agar were pale grayish brown, ellipsoid, rarely irregular in shape, and 8-11×4-7μm. The isolate grew slower than that of G. cingulata isolates from grape fruits on PDA at the optimum temperature. These morphological and physiological characteristics agreed with those of Colletotrichum acutatum Simmonds ex Simmonds. The ripe rot symptom was reproduced on grapevine fruits after inoculation with the isolate of C. acutatum. These results lead us to propose that C. acutatum, as well as G. cingulata, causes ripe rot of grapevine.