Research & reports

Tsuge Kazuki, Chen Ruikun, Yoshioka Yosuke, Motoki Satoru · The Horticulture Journal, 89(1): 12-21 · Japan

Using phenotypic traits and 24 SSR markers, this study assessed the genetic and phenotypic diversity of 'norabona', a traditional Brassica napus leaf-and-stem vegetable of the Kanto region, documenting diversity within this Japanese landrace.

Shirasawa Kenta, Hirakawa Hideki, Fukino Nobuko, Kitashiba Hiroyasu, Isobe Sachiko · DNA Research, 27(2): dsaa010 · Japan

The genome of 'Sakurajima Daikon', a giant-rooted traditional Japanese radish from Kagoshima, was sequenced and analyzed using long reads, providing a genomic foundation for trait studies and conservation of this landrace.

福本 優, 大平 和弘, 藤本 真里, 赤澤 宏樹 · 都市計画論文集 55巻3号 pp.777-782 · Japan

A case study of self-managed development parks under green-space agreements in private developer condominium projects in Kobe, analyzing spatial typologies and owner maintenance attitudes and showing the need for design guidance toward open green management including community gardens.

国土交通省 都市局 公園緑地・景観課 · 国土交通省（MLIT）報告書 · Japan

A Ministry of Land, Infrastructure, Transport and Tourism casebook compiled to advance both compact urban structure and the 'coexistence of cities with green and agriculture'. It catalogues urban-farming and green-space initiatives — including resident-participation rooftop gardens, allotments and farming-led town-making by private developers and municipalities — and provides the policy backdrop for developer cases.

Miyatake Koji, Shinmura Yoichi, Matsunaga Hiroshi, Fukuoka Hiroyuki, Saito Takeo · Breeding Science, 69(3): 498-502 · Japan

Analyzing 893 eggplant accessions in the NARO Genebank with genome-wide SNPs and SSRs, the authors built a core collection; Asian accessions formed the center of diversity, supporting efficient conservation and use of genetic resources.

横浜市 環境創造局 · 横浜市 都市農業推進計画 · Japan

Yokohama's urban agriculture promotion plan, linked to the Midori Up programme, organising policies and results for publicly supported citizen farming infrastructure including diverse citizen farms, cultivation experience farms, harvest farms and Megumi-no-Sato districts.

練馬区, 東京都都市整備局 · 練馬区 農の風景育成地区計画 · Japan

Nerima's landscape conservation plan for Minami-Oizumi and Takamatsu under Tokyo's Agricultural Landscape Conservation District system, positioning ward allotments, experience farms, farm stands and food-education events as integrated public farmland conservation and revitalisation.

ハジメ イシカワ, Hajime Ishikawa, 初 石川 · KeiO Associated Repository of Academic Resources (Keio University) · Japan (Tokamachi, Uji, Kamiyama)

This research aimed to establish a method for discovering, verbalizing, visualizing, and evaluating the "living scene" created by residents as a base for local identity and a local resource, and to clarify its sharing method. In 2020, in collaboration with local residents in Tokamachi City, Niigata Prefecture, and Uji City, Kyoto Prefecture, the study practiced verbalizing and sharing regional landscape elements through the production of landscape field guides. In Tokamachi City, private house gardens were measured and field guides created, while in Uji City, open spaces, green areas, and waterways were mapped, and community garden designs were proposed. In Kamiyama Town, fieldwork was abandoned due to COVID-19 countermeasures, and interview surveys were conducted using media such as telephone and email.

M. Tsuruta, Kyo Itoyama · Japanese Journal of Applied Entomology and Zoology · Japan (Kawasaki City)

This study investigated the seasonal occurrences and species composition of Orius spp. in an okra field in Kawasaki City, Japan. Orius spp. were found on okra plants from early-summer to early-autumn, with peak occurrences advancing with earlier flowering times. The initial occurrence was not associated with the seasonal prevalence of thrips on okra plants, suggesting that the main factors influencing Orius spp. occurrence are prey-independent.

特定非営利活動法人 Co.to.hana, 金田 康孝 · 国土交通省 都市と農・緑が共生するまちづくりに関する調査（平成29年度） · Japan (Osaka)

Co.to.hana's second-year MLIT study codifying how to reproduce Minna-no-uen's effects — activity data analysis since 2011, international comparables, intermediary-organisation needs, trial social-impact metrics, published as this report and at minnanouen.jp/research.

· 国土交通省都市局 · Japan

National materials on the Special Productive Greenland system created by the 2017 Productive Greenland Law amendment to address the '2022 problem,' extending buy-out timing and tax benefits by ten-year renewable periods; about 89% (8,282 ha) had been designated as of end-2022.

· 参議院常任委員会調査室『立法と調査』No.394 · Japan

Legislative analysis by the House of Councillors research office, organizing the regulatory framework for urban farmland (productive greenland, taxation, leasing) and examining the rationale and issues behind the 2018 lease law in light of the 2022 problem.

de St. Maurice G. · Food, Culture & Society 20(2) · Japan

Examines how Kyoto's Shishigatani heirloom squash, though considered not delicious, persists as culinary heritage through cultural embeddedness, temple rituals, and distinctive form, showing heritage value beyond flavor.

Plieninger T., Kohsaka R., Bieling C., Hashimoto S., Kamiyama C., Kizos T., Penker M., Kieninger P., Shaw B.J., Sioen G.B., Yoshida Y., Saito O. · Sustainability Science (Springer) · Japan

A 'solution scan' comparing place-based food networks (teikei, direct sales, farmers' markets) in Europe and Japan, systematizing how urban-rural food connection contributes to maintaining biocultural diversity.

農林水産省, 国土交通省 · 農林水産省（都市農業振興基本法に基づく政府の基本計画・閣議決定） · Japan

The government's basic plan under the Urban Agriculture Promotion Act (2015). It places 'realising the diverse functions of urban agriculture' at the centre and sets three new policy directions: securing urban farmers, securing land for farming, and full-scale agricultural-promotion measures. It is the core plan underpinning municipalities' citizen farms, experience farms and farmland conservation nationwide.

Ministry of the Environment, Government of Japan · Ministry of the Environment, Government of Japan · Japan

A practitioner handbook compiled by Japan's Ministry of the Environment on Eco-DRR (Ecosystem-based Disaster Risk Reduction). It systematizes the use of ecosystems and traditional land use—forests preventing soil erosion, coastal forests attenuating tsunamis, wetlands and paddy fields providing temporary flood storage—to achieve disaster risk reduction and biodiversity conservation simultaneously, providing a policy basis for treating urban and rural farmland and greenery as protective green infrastructure.

Takahashi Yu, Yokoi Shuji, Takahata Yoshihito · Genetic Resources and Crop Evolution, 63(5): 869-879 · Japan

Analysis of 87 turnip accessions using chloroplast and nuclear SSRs and morphology revealed distinct haplogroups between eastern and western Eurasia, with continental Asian accessions (including Japan) showing the highest genetic diversity.

Iketani Hiroyuki · Breeding Science, 66(1): 82-89 · Japan

A review of Japan's native fruit tree genetic resources shaped by its diverse climate, summarizing the status of wild and local fruit taxa, red-listed species, and the state of conservation in genebanks and botanical gardens.

Nishio Sogo, Takada Norio, Saito Toshihiro, Yamamoto Toshiya, Iketani Hiroyuki · BMC Genetics, 17: 81 · Japan

Comparing wild, Chinese, local, and modern Japanese pear cultivars, the study found reduced heterozygosity and allelic richness in modern cultivars, which were genetically close to Kanto local cultivars and strongly biased toward 'Nijisseiki'.

Sakurai Shin · Nippon.com · Japan

A feature on the Ginza Honey Bee Project ('Ginpachi'), a nonprofit founded in March 2006 by Tanaka Atsuo, which installed beehives on the roof of the Kami Parupu Kaikan building in central Tokyo, drawing nectar from Hibiya Park and the Imperial Palace grounds within roughly a 3km radius. A decade on, the project has grown to 150 members, supplies honey products sold at the Matsuya Ginza department store and honey cocktails at nearby bars, and has inspired more than 100 urban beekeeping projects nationwide as well as projects in South Korea, Taiwan and elsewhere in Asia.

· 農林水産省・国土交通省 · Japan

Government explainer of the 2015 Urban Agriculture Promotion Basic Law, setting out its purpose, principles, and the responsibilities of national and local governments, and articulating the multifunctional roles of urban agriculture.

山口 創 · 食資源教育研究センター報告（CEIS Papers）, 29: 83-88 · Japan

Through interview surveys of three cases (Komoike-dainagon bean, Harima-o garlic, Himeji-ebiimo taro), this paper analyzes the process by which local varieties become recognized regional resources and the challenges of their development.

国土交通省 都市局 · 国土交通省 委託調査報告書 · Japan

MLIT commissioned survey on Setagaya's productive-greenbelt designation, landscape-farmland districts, citizen farms and agricultural parks as models of urban farmland preservation and public-participation farming under public support.

Takanori Kuronuma, Saori Hashimoto, Ryuta CHIMURA, Haruaki YOKOKAWA, Kazunori Sakamoto, Hitoshi Watanabe · Journal of the Japanese Society of Revegetation Technology · Japan

This study investigated the annual changes in lightweight soil in a thin substratum rooftop garden planted with Zoysia grass. No annual changes were observed in grass growth or soil physical properties. Soil organic matter tended to increase after construction, and nutrient salt content was comparable to golf course green soil diagnostic standards. However, nutrient salt levels in unused lightweight soil were significantly higher than after construction and decreased annually. No difference in nutrient salt content was confirmed with or without additional fertilization, suggesting the need for fertilization management tailored to the unique rooftop environment.

東京都都市整備局 · 東京都都市整備局（民有地の緑の保全・創出 制度） · Japan

A Tokyo system created in 2011 to conserve dwindling farmland as open space and carry the agricultural landscape into the future. Districts where farmland and homestead groves remain clustered are designated so that scattered farmland can be conserved collectively as urban-planning parks/green space. Designations include Setagaya's Kitami (the first) and Nerima's Takamatsu and Minami-Oizumi, providing the policy framework for municipal urban-farmland conservation.