Hideki Miyamoto, S. Yoshida, J. Chikushi, T. Eguchi, Yuji Ito
{"title":"Estimation of Moisture Conditions in Organic and Inorganic Growing Media Based on Hydraulic Properties","authors":"Hideki Miyamoto, S. Yoshida, J. Chikushi, T. Eguchi, Yuji Ito","doi":"10.2525/SHITA.21.72","DOIUrl":"https://doi.org/10.2525/SHITA.21.72","url":null,"abstract":"水管理条件がヤシ殻培地中の水分環境に及ぼす影響を調べることを目的として,ヤシ殻と他の培地(砂およびロックウール)の保水性と透水性を測定した.そして,得られた測定結果と土中の鉛直1次元水分移動方程式に基づいて数値シミュレーションを実施し,各培地を同一環境下で用いた場合に予測される水分環境の差異について検討したところ,以下の知見を得た.(1) ロックウールとヤシ殻は高い水分保持能を持ち,特に緻密な間隙構造を有するヤシ殻は,極めて高い保水性を有することが明らかになった.(2) 全培地の透水性は,水分量の低下とともに指数関数的に低下した.なかでも,ヤシ殻は,透水性が他の培地よりも数オーダ低かったことから,水分移動が著しく阻害され易い培地であることが明らかになった.(3) 底面給液条件における数値シミュレーションより,同一条件で水管理を行っても,培地内の水分の量および圧力は培地によって異なること,またその差異が保水性や透水性といった培地固有の水分移動特性に起因することが明らかになった.(4) 多種多様な環境下における水分状態を予測できる数値シミュレーションは,作物の生育に適した水管理システムを構築するうえで有用な手法と考えられた.","PeriodicalId":315038,"journal":{"name":"Shokubutsu Kankyo Kogaku","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130545669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Production of value-added vegetables by applying environmental stresses to roots in soil-less culture","authors":"M. Kitano, K. Hidaka, K. Zushi, T. Araki","doi":"10.2525/SHITA.20.210","DOIUrl":"https://doi.org/10.2525/SHITA.20.210","url":null,"abstract":"In the root zone of the soil-less culture, stress conditions such as low temperature, drought and high salinity can be easily introduced and controlled by applying physical and chemical characteristics of water. These stress conditions in the root zone cause depres-sions in root absorption and leaf photosynthesis and resultantly bring osmotic stress and oxidative stress in the plant body. The osmotic stress and the oxidative stress can induce the respective plant adaptive functions of osmotic adjustment and antioxidation. These plant functions can be expected to bring high quality and value-added vegetables enriched with sugars, functional amino acids, antioxidants etc., if the induced stresses are not so serious that the stress damages are not fatal without the extreme depression in growth. In this paper, two examples of the short term stress application only to roots for production of value-added vegetables are demonstrated. By the one week application of low temperature (5℃) stress only to roots of spinach plants (Spinacia oleracea L.), sugars, ascorbic acid and Fe2+ were significantly enriched in leaves. Furthermore, concentrations of harmful substances of NO3- and oxalic acid were extremely decreased. The two weeks salt stress treatment to roots of tomato plants (Lycopersicon esculentum Mill.) by applying the Muroto deep seawater at the stage of rapid fruit growth induced the osmotic adjustment and the antioxidation, which brought high quality tomatoes enriched with sugar, minerals, functional amino acids and good flavour without occurrence of extremely small-sized fruits and blossom-end rot. These verify that the short term stress application only to roots in the soil-less culture is reliable for production of high quality and value-added vegetables.","PeriodicalId":315038,"journal":{"name":"Shokubutsu Kankyo Kogaku","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122184745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Plant growth under hypobaric conditions","authors":"Y. Ishigami, E. Goto","doi":"10.2525/SHITA.20.228","DOIUrl":"https://doi.org/10.2525/SHITA.20.228","url":null,"abstract":"In order to achieve plant production in a closed ecological life support system (CELSS) in space, environmental control is a key technology because the environment is completely artificial. One advantage of the CELSS in space is that each module's gas composition and total pressure can be regulated at an optimal level. For example, the nitrogen contained in air is not necessary for plant growth, and low oxygen concentration may enhance net photosynthesis by reducing photorespiration. Hypobaric conditions, obtained by reducing nitrogen and oxygen concentrations, could facilitate gas control, reduce construction costs, and simplify maintenance of modules on a lunar base and in plant production systems on Mars. This review summarizes previous papers and evaluates significant effects of total pressure on growth and development of higher plants, especially crops. Previous studies showed that photosynthesis and transpiration of plants were enhanced under low total pressures because gas diffusion rates increase at low total pressures. Spinach and lettuce in vegetative stages can grow normally under 25 to 50 kPa total pressures. Seeds of rice and Arabidopsis thaliana germinated at 25 kPa total pressure. Flowering was normal in Arabidopsis under hypobaric conditions. Seed growth of soybean and Arabidopsis under low total pressures with a low O2 partial pressure was greater than under the atmospheric pressure with the same O2 partial pressure. This indicates that O2 concentrations inside siliques were maintained higher by the higher diffusion rates prevailing under hypobaric conditions. The results indicate that if total and partial pressures are controlled precisely, plants can grow normally in their life cycle from germination to harvest under hypobaric conditions.","PeriodicalId":315038,"journal":{"name":"Shokubutsu Kankyo Kogaku","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131208836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effects of Cultivar, Decapitation and Training Direction on the Uniformity and Number of Lateral Shoots in the Vegetative Propagation of Tomato Plants","authors":"M. Oda, Mey Huang, H. Ikeda, H. Furukawa","doi":"10.2525/SHITA.20.152","DOIUrl":"https://doi.org/10.2525/SHITA.20.152","url":null,"abstract":"栄養繁殖を前提として育成されたトマト品種を側枝で増殖する場合に,葉位間で均一な側枝をより多く発達させることを目的として,側枝の発達に及ぼす品種,主茎の摘心および誘引方向の影響を調べるとともに,露地栽培で確認した.その結果,1) 側枝発生数に品種間差異はないが,発達速度には,果実のタイプで分けられる品種間差異がある,2) 摘心は下葉位の側枝の発達を促進して各葉位の側枝長が均一化するが,ほぼ同じ大きさの側枝を得るには至らない,3) 側枝採取数は,水平誘引によって処理直後には増えるが,最終的には母株の葉腋数によって制限される,4) 二次側枝の利用により65倍程度の増殖効率になることが明らかになった.","PeriodicalId":315038,"journal":{"name":"Shokubutsu Kankyo Kogaku","volume":"101 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2008-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124470575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}