{"created":"2025-07-10T01:12:35.354969+00:00","id":2001263,"links":{},"metadata":{"_buckets":{"deposit":"40ef4f28-1d0f-439a-ac98-2935448299ef"},"_deposit":{"created_by":24,"id":"2001263","owners":[24],"pid":{"revision_id":0,"type":"depid","value":"2001263"},"status":"published"},"_oai":{"id":"oai:ir.kagoshima-u.ac.jp:02001263","sets":["228:265:1750913942939","43:194:6019"]},"author_link":["2454","144863","144877","144879"],"item_7_biblio_info_5":{"attribute_name":"収録雑誌名","attribute_value_mlt":[{"bibliographicIssueDates":{"bibliographicIssueDate":"2025-03-01","bibliographicIssueDateType":"Issued"},"bibliographicPageEnd":"12","bibliographicPageStart":"1","bibliographicVolumeNumber":"49","bibliographic_titles":[{"bibliographic_title":"鹿児島大学農学部演習林研究報告","bibliographic_titleLang":"ja"},{"bibliographic_title":"Research bulletin of the Kagoshima University forests","bibliographic_titleLang":"en"}]}]},"item_7_date_6":{"attribute_name":"作成日","attribute_value_mlt":[{"subitem_date_issued_datetime":"2025-03-01","subitem_date_issued_type":"Issued"}]},"item_7_description_4":{"attribute_name":"要約(Abstract)","attribute_value_mlt":[{"subitem_description":"• Research objective: Apostasioideae, the basal-most subfamily of orchids, comprises two genera, Apostasia and Neuwiedia, which occur in forests in tropical and subtropical parts of Asia, Australia and the Southwest Pacific. A single species occurs in southern Japan, Apostasia nipponica, which is morphologically similar to the very widespread A. wallichii. The former can be distinguished from the latter on account of its considerably smaller stature (up to 15 cm versus up to 1 m tall), as well as differences in leaf shape and dimensions (ovate-lanceolate and up to 4 cm long, versus linear and up to 50 cm long) and the number of flowers in the inflorescence (fewer than ten versus up to 30). Both are perennial, green, partial myco-heterotrophs that form mycorrhizal root tubercles with ectomycorrhizal fungi. Apostasia nipponica has been reported to receive ≥84% of its carbon from its mycobiont, presenting an interesting topic for comparison with A. wallichii. However, anatomical and ecological features of either species that may be important to the myco-heterotrophic habit remain largely unstudied; the same is true with respect to the possibility of asexual propagation. Because A. nipponica is an endangered species in Japan, knowledge of its ecological characteristics would be useful for its conservation.\n• Methods: We examined the habitat, growth habit, phenology, anatomical and physiological characteristics of tuberous root of A. nipponica, and compared our findings with descriptions of A. wallichii.\n• Results: Plants of A. nipponica live for at least five years and have a sparse, scattered or clumped occurrence in forests dominated by ectomycorrhizal trees belonging to the Fagaceae. Although plants may decrease in number as a result of wild boar rooting behavior, populations can establish beside man-made trails and at other sites subject to disturbance. Fruits remain green on the stem for about 10 months, with the present year’s capsules undergoing development only once those from the previous year are detached. Underground parts comprise a rhizome and tuberous roots that lie within the A-horizon of the soil, and account for considerably more biomass than above-ground parts. Tuberous roots adopt a clavate form and have a warty surface, via which mycobionts enter and colonize the cortex. The cortex is partitioned into five discrete zones and zone 3 (digestion cell layer) is composed of exceptionally large cells, as has been described for A. wallichii. The tuberous roots of A. nipponica are thicker than those of A. wallichii (5 mm diameter in the former versus 3.5 mm in the latter), which is attributed to approximately double the number of cell layers of zone 2 (host cell layer). In fact, the host cell layer accounts for approximately 53% of the cross-sectional area of A. nipponica roots, as compared with 34% in A. wallichii roots. Our observations confirm that A. nipponica can propagate through division of both the rhizome and tuberous roots, representing the first report of clonal propagation in the Apostasioideae.\n• Conclusions: Apostasia nipponica appears to exhibit increased dependence on mycotrophy as compared with A. wallichii, as evidenced by both reduction in above-ground biomass relative to rootstock biomass and increased proportion of the host cell layer in tuberous roots. We infer that these features facilitate the establishment of stable associations with ectomycorrhizal mycobionts present in Fagaceae-dominated forests. Although the species is capable of both asexual propagation and sexual reproduction, habitat disturbance is an important limiting factor for population growth and survival at some sites. Tuberous roots function as storage organs. Crickets, the known seed-dispersal agent, may play a crucial role in the removal of capsules from the previous year, thereby facilitating the maturation of those formed in the present year. The occurrence of this species at disturbed sites suggests the potential for cultivation by embedding seeds below leaf litter around the base of Fagaceae trees.","subitem_description_language":"en","subitem_description_type":"Other"},{"subitem_description":"（研究の目的）ヤクシマラン亜科はラン科植物の祖型と考えられApostasia 属とNeuwiedia 属の2属からなり，アジアとオーストラリアの熱帯～亜熱帯の森林と南西太平洋地域の森林に分布する。日本ではヤクシマラン（Apostasia nipponica）1種が南日本に産し，広範囲に分布するA. wallichii と形態学的に類似する。しかし，本種はA. wallichii と以下の点で識別が可能である―かなり小型である（草丈15 cm に対し1 m）；葉の形と大きさが異なる（卵状披針形で葉長4 cm に対し線形で葉長50cm）；花序の花の数が異なる（10個以下に対し30個以上）。両種とも常緑の永年性植物であり，また，部分的菌類従属栄養植物であり，地下の塊根（Tuberous root）で外生菌根菌と共生関係を樹立している。ヤクシマランは驚くべきことに炭素源の84％以上を共生菌から得ている。それ故，本種は共生菌への栄養依存性をA. wallichii と比較する上で興味深いが，菌類従属栄養に関する両種の解剖的，生態的特徴についてはほとんど研究されていない。また，同様に栄養繁殖に関する研究も無い。ヤクシマランは日本では絶滅が危惧されているため，その生態的特質を知ることは本種の保全に有効であると考えられる。\n（研究の方法）植物の発生および発生地特性，フェノロジー，塊根の解剖的・生理的特徴を調べ，A. wallichii についての記述と比較した。\n（研究の結果）ヤクシマランは外生菌根共生を行うブナ科植物を優占種とする森林に孤生，散生，群生状に発生し，少なくとも5年以上は生育する。ヤクシマランはイノシシの求餌によると思われる林地攪乱場所で発生数が減少するが，人工的に作られた山道などで発生が可能である。果実はおよそ10か月間緑色のまま茎頂に残存し，前年度の果実が無くなってから成長を開始する。地下器官は根茎と塊根から構成され，塊根は土壌層位A 層に位置している。地下器官は地上器官よりはるかに大きい。塊根は根棒状で表面は小イボ状を呈し，イボを通して共生菌は皮層に侵入し，そこで菌毬を形成する。塊根の皮層は5層に分かれ，中でも第3層（消化層）の細胞はとりわけ大きく，A. wallichii と同様である。塊根の太さはA. wallichii の3.5mm に比べ5mm と太く，その主な原因は，第2層（菌棲層）の層数がA. wallichii の約2倍であることによる。事実，ヤクシマランの菌棲層の断面積は根の全断面積のおよそ53％を占め，A. wallichii のそれは34％である。根茎および塊根よる栄養繁殖が確認され，このことはヤクシマラン亜科で初の知見である。\n（結論）ヤクシマランはA. wallichii に比べて，地下部のバイオマス量よりも地上部のバイオマス量を減少させ，更に，地下部の塊根（菌根）の菌棲層を増加させたことによって，菌類への栄養依存を高めたと考えられる。このとから，ヤクシマランはブナ科優占の森林で，ブナ科樹木の外生菌根菌と安定した共生関係を促進していると考えられる。種子繁殖と栄養繁殖を行うが，ある地域では発生地の攪乱は本種生存の重要な制限因子の一つとなっている。塊根には貯蔵器官としての機能がある。ヤクシマランの種子散布者であるコオロギ類は，前年度種子の除去に重要な役割を果たしているものと思われる。そのことによって，当年生種子は成熟が促進されると考えられる。生育地攪乱場所でのヤクシマランの発生は，種子をブナ科樹木の周囲の落葉下に埋設すれば，人工的に増殖の可能性がある。","subitem_description_language":"ja","subitem_description_type":"Other"}]},"item_7_publisher_23":{"attribute_name":"公開者・出版者","attribute_value_mlt":[{"subitem_publisher":"鹿児島大学","subitem_publisher_language":"ja"},{"subitem_publisher":"Kagoshima University","subitem_publisher_language":"en"}]},"item_7_source_id_7":{"attribute_name":"ISSN","attribute_value_mlt":[{"subitem_source_identifier":"13449362","subitem_source_identifier_type":"PISSN"}]},"item_7_source_id_9":{"attribute_name":"NII書誌ID","attribute_value_mlt":[{"subitem_source_identifier":"AN10592752","subitem_source_identifier_type":"NCID"}]},"item_7_version_type_14":{"attribute_name":"著者版フラグ","attribute_value_mlt":[{"subitem_version_resource":"http://purl.org/coar/version/c_970fb48d4fbd8a85","subitem_version_type":"VoR"}]},"item_access_right":{"attribute_name":"アクセス権","attribute_value_mlt":[{"subitem_access_right":"open access","subitem_access_right_uri":"http://purl.org/coar/access_right/c_abf2"}]},"item_creator":{"attribute_name":"著者","attribute_type":"creator","attribute_value_mlt":[{"creatorNames":[{"creatorName":"馬田, 英隆","creatorNameLang":"ja"},{"creatorName":"Umata, Hidetaka","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"2454","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"ゲイル, ステファン・ウイリアム","creatorNameLang":"ja"},{"creatorName":"Gale, Stephan W.","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"144863","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"高木, 正博","creatorNameLang":"ja"},{"creatorName":"Takagi, Masahiro","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"144877","nameIdentifierScheme":"WEKO"}]},{"creatorNames":[{"creatorName":"辻田, 有希","creatorNameLang":"ja"},{"creatorName":"Ogura-Tsujita, Yuki","creatorNameLang":"en"}],"nameIdentifiers":[{"nameIdentifier":"144879","nameIdentifierScheme":"WEKO"}]}]},"item_files":{"attribute_name":"ファイル情報","attribute_type":"file","attribute_value_mlt":[{"accessrole":"open_access","date":[{"dateType":"Available","dateValue":"2025-07-10"}],"displaytype":"detail","fileDate":[{"fileDateType":"Issued","fileDateValue":"2025-03-01"}],"filename":"AN10592752_v49_p1-12.pdf","filesize":[{"value":"1.4 MB"}],"format":"application/pdf","mimetype":"application/pdf","url":{"label":"AN10592752_v49_p1-12.pdf","objectType":"fulltext","url":"https://ir.kagoshima-u.ac.jp/record/2001263/files/AN10592752_v49_p1-12.pdf"},"version_id":"031065d0-b0fd-458b-baad-b2fedba0d370"}]},"item_keyword":{"attribute_name":"キーワード","attribute_value_mlt":[{"subitem_subject":"Apostasia nipponica","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"Apostasia wallichii","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"partial mycoheterotrophy","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"root tubercle","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"mycorrhizal symbiosis","subitem_subject_language":"en","subitem_subject_scheme":"Other"},{"subitem_subject":"ヤクシマラン","subitem_subject_language":"ja","subitem_subject_scheme":"Other"},{"subitem_subject":"Apostasia wallichii","subitem_subject_language":"ja","subitem_subject_scheme":"Other"},{"subitem_subject":"部分的菌類従属栄養","subitem_subject_language":"ja","subitem_subject_scheme":"Other"},{"subitem_subject":"塊根","subitem_subject_language":"ja","subitem_subject_scheme":"Other"},{"subitem_subject":"菌根共生","subitem_subject_language":"ja","subitem_subject_scheme":"Other"}]},"item_language":{"attribute_name":"言語","attribute_value_mlt":[{"subitem_language":"eng"}]},"item_resource_type":{"attribute_name":"資源タイプ","attribute_value_mlt":[{"resourcetype":"departmental bulletin paper","resourceuri":"http://purl.org/coar/resource_type/c_6501"}]},"item_title":"Anatomical and ecological characteristics of Apostasia nipponica, a basalmost orchid, in light of high mycobiont dependence","item_titles":{"attribute_name":"タイトル","attribute_value_mlt":[{"subitem_title":"Anatomical and ecological characteristics of Apostasia nipponica, a basalmost orchid, in light of high mycobiont dependence","subitem_title_language":"en"},{"subitem_title":"高度な菌類依存の観点からみたラン科植物の祖型ヤクシマランの解剖的および生態的特質","subitem_title_language":"ja"}]},"item_type_id":"7","owner":"24","path":["6019","1750913942939"],"pubdate":{"attribute_name":"PubDate","attribute_value":"2025-07-10"},"publish_date":"2025-07-10","publish_status":"0","recid":"2001263","relation_version_is_last":true,"title":["Anatomical and ecological characteristics of Apostasia nipponica, a basalmost orchid, in light of high mycobiont dependence"],"weko_creator_id":"24","weko_shared_id":-1},"updated":"2025-07-10T01:56:30.546953+00:00"}