start-ver=1.4 cd-journal=joma no-vol=3 cd-vols= no-issue=2 article-no= start-page=163 end-page=174 dt-received= dt-revised= dt-accepted= dt-pub-year=1995 dt-pub=1995 dt-online= en-article= kn-article= en-subject= kn-subject= en-title=Odontoglossum Ringspot Virus Isolated from Calanthe sp. in Japan kn-title=エビネ(Calanthe sp.)から分離されたOdontoglossum Ringspot　Virus en-subtitle= kn-subtitle= en-abstract=1992年に採集した退緑斑紋を示すエビネから棒状ウイルスとひも状ウイルスが検出され、この棒状ウイルスはその性質から odontoglossum ringspot virus(ORSV) と同定された。本ウイルスは汁液接種により供試した12科40種のうち、6科14種に感染した。DN法試料の電顕観察では長さ約310nmのウイルス粒子が観察された。本ウイルスの感染Chenopodium quinoa 細胞中には散在あるいは大集塊したウイルス粒子が観察された。ウイルス外被タンパク質の分子量は約20,600あり、Cymbidium からのORSV 2分離株とほぼ同じであったが、他の１つCymbidium からのCy-1 分離株は上記の分離株よりわずかに大きかった（約20,900）。本ウイルスと他のORSV分離株はいずれも寒天ゲル内二重拡散法、直接二重酵素結合抗体法（DAS-ELISA）でCy-1分離株の抗血清とよく反応したが、同じ抗血清に対してtabacco mosaic virus 普通系とは反応しなかった。ORSVエビネ分離株はウイルス感染に特異的な二本鎖RNAの電気泳動でも他のORSVと同様のパターンを示した。以上、ORSVエビネ分離株は既報のORSV分離株と血清学的に同じであり、それらと近似の系統と考えられた。 kn-abstract=A rod-shape virus isolated from Calanthe sp. showing chlorotic mottle on the leaves, collected in Ibaraki Prefecture, was identified as odontoglossum ringspot virus(ORSV). The isolate,designated as Cal.92-1T, was transmitted by sap-inoculation to 14 out of 40 species in 6 out of 12 families. The virus particles were rod-shaped, about 310 nm long. In ultrahtin sections, the dispersed and aggregated virus particles were observed in the cytoplasm of the cells of the infected leaves of Chenopodium quinoa. The virus contained a single protein species of Mr 20,600. The Mr of the capsid proteins(Cal.92-1T) was similar to those of three other ORSV isolates(Cy-1,Cy-46,Cy-Kei). Cal.92-1T isolate(Cy-1), suggesting that Cal.92-1T was serologically very similar to the other ORSV isolates. Three species of dsRNA were isolated from plants infected with Cal.92-1T and they were similar to those of three other ORSV isolates. en-copyright= kn-copyright= en-aut-name=MatsumotoJun-ichi en-aut-sei=Matsumoto en-aut-mei=Jun-ichi kn-aut-name=松本純一 kn-aut-sei=松本 kn-aut-mei=純一 aut-affil-num=1 ORCID= en-aut-name=MaedaTakanori en-aut-sei=Maeda en-aut-mei=Takanori kn-aut-name=前田孚憲 kn-aut-sei=前田 kn-aut-mei=孚憲 aut-affil-num=2 ORCID= en-aut-name=InouyeNarinobu en-aut-sei=Inouye en-aut-mei=Narinobu kn-aut-name=井上成信 kn-aut-sei=井上 kn-aut-mei=成信 aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=岡山大学 affil-num=2 en-affil= kn-affil=岡山大学 affil-num=3 en-affil= kn-affil=岡山大学 en-keyword=Odontoglossum ringspot virus kn-keyword=Odontoglossum ringspot virus en-keyword=Calanthe sp. kn-keyword=Calanthe sp. en-keyword=Identification kn-keyword=Identification END start-ver=1.4 cd-journal=joma no-vol=3 cd-vols= no-issue=2 article-no= start-page=151 end-page=161 dt-received= dt-revised= dt-accepted= dt-pub-year=1995 dt-pub=1995 dt-online= en-article= kn-article= en-subject= kn-subject= en-title=Host Range and Some Properties of Orchid Fleck Virus Isolated form Oriental Cymbidium in Japan kn-title=東洋ラン(Cymbidium sp.)から分離されたOrchid Fleck Virusの性状について en-subtitle= kn-subtitle= en-abstract=1992年10月岡山市内で採集した葉に退緑斑点症状を示す東洋ラン（Cymbidium sp.）より分離されたウイルスはランえそ斑紋ウイルス（orchid fleck virus;OFV）と同定された。本ウイルスは汁液接種を行った11科41種の植物のうち、アカザ科のChenopodium murale, C.quinoa, Beta vulgalis の3種に全身感染し、ツルナ、C.amaranticolar,ササゲ、ペチュニア、Nicotiana glutinosa の4科5種に局部感染した。本ウイルスは病葉粗汁液中では安定性が低く、ツルナ粗汁液での安定性は耐熱性40〜45℃、耐希釈性10-3〜10-4、耐保存性30〜45分であった。DN法試料の電顕観察ではウイルス粒子は長さ120〜150nm、幅約40nmの被膜のない弾丸状であった。感染葉の超薄切片では約120〜140×40nm の短桿状粒子として観察された。感染細胞の超薄切片像ではウイルス粒子が各種細胞に観察された。また感染細胞の核内には封入体（viroplasm）が認められ、その周辺や内部に粒子が集塊あるいは散在して認められた。さらに核膜近傍ではウイルス粒子が核膜内膜に吸着したもの認められ、その細胞質側には車輪状などに配列した膜系に包まれた粒子集団が認められた。 kn-abstract=Orchid flck virus (OFV) was isolated from Oriental Cymbidium (Cymbidium sp.),showing chlorotic flecks on leaves. The virus was transmitted mechanically to Chenopodium quinoa,C.murale and Beta vulgaris by sap-inoculation and caused systemic infection. Local lesions were produced on C.amaranticolar, Petunia hybrida, Tetragonia expansa and Vigna sinensis. Sap from infected T.expansa was still infective after 10 mim at 40℃ but not after 10 min at 45℃, at a dilution of 10-3 but not 10-4, and after 30 min at room temperature but not after 60 min. The isolate of OFV had non-enveloped, bullet-shaped patricles measuring about 40×120−150 nm in dip preparations. However, bacilliform particles about 40×120-140 nm were observed in ultrathin sections. In ultrahtin sections of virus-infected tissues, virus patricles were detected both in the nuclei and in the cytoplasm. Moreover, the inclusions of low electron density(viroplasm) were also observed in the nuclei.Virus particles were found to attach at one end to the inner nuclear membrane. A number of particles surrounded by the inner membrane often showed an appearance like a spoked wheel. en-copyright= kn-copyright= en-aut-name=KondoHideki en-aut-sei=Kondo en-aut-mei=Hideki kn-aut-name=近藤秀樹 kn-aut-sei=近藤 kn-aut-mei=秀樹 aut-affil-num=1 ORCID= en-aut-name=MatsumotoJun-ichi en-aut-sei=Matsumoto en-aut-mei=Jun-ichi kn-aut-name=松本純一 kn-aut-sei=松本 kn-aut-mei=純一 aut-affil-num=2 ORCID= en-aut-name=MaedaTakanori en-aut-sei=Maeda en-aut-mei=Takanori kn-aut-name=前田孚憲 kn-aut-sei=前田 kn-aut-mei=孚憲 aut-affil-num=3 ORCID= en-aut-name=InouyeNarinobu en-aut-sei=Inouye en-aut-mei=Narinobu kn-aut-name=井上成信 kn-aut-sei=井上 kn-aut-mei=成信 aut-affil-num=4 ORCID= affil-num=1 en-affil= kn-affil=岡山大学 affil-num=2 en-affil= kn-affil=岡山大学 affil-num=3 en-affil= kn-affil=岡山大学 affil-num=4 en-affil= kn-affil=岡山大学 en-keyword=Orchid fleck virus kn-keyword=Orchid fleck virus en-keyword=Oriental Cymbidium kn-keyword=Oriental Cymbidium en-keyword=Non-enveloped rhabdovirus like particles kn-keyword=Non-enveloped rhabdovirus like particles END start-ver=1.4 cd-journal=joma no-vol=3 cd-vols= no-issue=2 article-no= start-page=145 end-page=149 dt-received= dt-revised= dt-accepted= dt-pub-year=1995 dt-pub=1995 dt-online= en-article= kn-article= en-subject= kn-subject= en-title=Cloning of PCR-Products Encoding Potassium Channel Proteins from Mesembryanthemum crystallinum kn-title=Mesembryanthemum crystallinum(ice plant)におけるカリウムチャンネルをコードするPCR産物のクローニング en-subtitle= kn-subtitle= en-abstract=耐塩性、耐乾性の極めて高い Mesembryanthemum crystallinum からPCR法を用いてカリウムチャンネル遺伝子断片を得た。2つのクローンが独立に得られたが、互いによく似ていて、シロイヌナズナのカリウムチャンネルとは67から88％の相同性を示した。サザンハイブリダイゼーションの結果から、今回得られた遺伝子はシングルコピーであり、またカリウムチャンネル遺伝子ファミリーが存在する可能性が示唆された。 kn-abstract=Gene fragments of potassium channels were cloned from Mesembryanthemum crystallinum by using RT-PCR (reverse transcription-polymerase chain reaction). The two fragments were isolated independently and showed high similarity with each other. About 80% identity was found between the two fragments and potassium-channel genes of Arabidopsis. Southern hybridization indicated that the potassium channel gene may be a single copy gene or that a small gene family of potassium channels exists. en-copyright= kn-copyright= en-aut-name=KatsuharaMaki en-aut-sei=Katsuhara en-aut-mei=Maki kn-aut-name=且原真木 kn-aut-sei=且原 kn-aut-mei=真木 aut-affil-num=1 ORCID= en-aut-name=BohnertHans J. en-aut-sei=Bohnert en-aut-mei=Hans J. kn-aut-name=BohnertHans J. kn-aut-sei=Bohnert kn-aut-mei=Hans J. aut-affil-num=2 ORCID= affil-num=1 en-affil= kn-affil=岡山大学 affil-num=2 en-affil= kn-affil=岡山大学 en-keyword=Mesembryanthemum crystallinum kn-keyword=Mesembryanthemum crystallinum en-keyword=Potassium channel kn-keyword=Potassium channel en-keyword=RT-PCR kn-keyword=RT-PCR END start-ver=1.4 cd-journal=joma no-vol=3 cd-vols= no-issue=2 article-no= start-page=137 end-page=143 dt-received= dt-revised= dt-accepted= dt-pub-year=1995 dt-pub=1995 dt-online= en-article= kn-article= en-subject= kn-subject= en-title=Evaluation of Three Different Procedures for Extracting Adenylates from Barley Roots Prior to Luminometric Quantification kn-title=ルシフェリン―ルシフェラーゼ法によるアデニル酸定量のための大麦根からのサンプル抽出方法の検討 en-subtitle= kn-subtitle= en-abstract=高等植物根のアデニル酸をルシフェリン−ルシフェラーゼ法による定量に適する抽出法を捜すために、数種の抽出法を比べた。過塩素酸で抽出し、オクチルアミンで中和し、フロンの一種で洗う方法が最も抽出効果が高く、また比較的操作が簡便であった。 kn-abstract=Three methods were compared for extracting adenylates from barley roots prior to their quantification by a lumino-metric method. In respect of efficiency in extracting adenylates and easiness in handling, the best result was obtained in the root sample which was homogenized in perchloric acid, neutralized by mixing with octylamine dissolved in 1,1,2-trichloro-1,2,2-trifluoroethane and centrifuged. en-copyright= kn-copyright= en-aut-name=AkiyamaYoshiko en-aut-sei=Akiyama en-aut-mei=Yoshiko kn-aut-name=秋山佳子 kn-aut-sei=秋山 kn-aut-mei=佳子 aut-affil-num=1 ORCID= en-aut-name=ShibasakaMineo en-aut-sei=Shibasaka en-aut-mei=Mineo kn-aut-name=柴坂三根夫 kn-aut-sei=柴坂 kn-aut-mei=三根夫 aut-affil-num=2 ORCID= en-aut-name=KawasakiToshio en-aut-sei=Kawasaki en-aut-mei=Toshio kn-aut-name=河ｱ利夫 kn-aut-sei=河ｱ kn-aut-mei=利夫 aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=岡山大学 affil-num=2 en-affil= kn-affil=岡山大学 affil-num=3 en-affil= kn-affil=岡山大学 en-keyword=Adenylate extraction kn-keyword=Adenylate extraction en-keyword=ADP kn-keyword=ADP en-keyword=AMP kn-keyword=AMP en-keyword=ATP kn-keyword=ATP en-keyword=Barley roots kn-keyword=Barley roots END start-ver=1.4 cd-journal=joma no-vol=3 cd-vols= no-issue=2 article-no= start-page=129 end-page=135 dt-received= dt-revised= dt-accepted= dt-pub-year=1995 dt-pub=1995 dt-online= en-article= kn-article= en-subject= kn-subject= en-title=Effects of Mannosen on Hydroponically Grown Barley kn-title=水耕栽培におけるオオムギの生育に及ぼすマンノースの影響 en-subtitle= kn-subtitle= en-abstract=薄いマンノース溶液がオオムギの養分吸収に及ぼす影響を調べるために、水耕栽培実験を行った。マンノース添加の有無は植物体のカリウム及びリン酸含量にはほとんど影響しなかったが、植物体の形態に若干の影響を与えた。 kn-abstract=To examin the effects of mannose on iron absorption of barley roots,barley was hydroponically grown for 36 days in a greenhouse. Potassium and phosphate of barley plants grown in a diluted mannose solution were obserbed at similar as the controls. On the otherhand, some morphological changes were observed in mannose-treated barley plants. en-copyright= kn-copyright= en-aut-name=ShibasakaMineo en-aut-sei=Shibasaka en-aut-mei=Mineo kn-aut-name=柴坂三根夫 kn-aut-sei=柴坂 kn-aut-mei=三根夫 aut-affil-num=1 ORCID= en-aut-name=MiyataMasahiko en-aut-sei=Miyata en-aut-mei=Masahiko kn-aut-name=宮田將彦 kn-aut-sei=宮田 kn-aut-mei=將彦 aut-affil-num=2 ORCID= en-aut-name=AkiyamaYoshiko en-aut-sei=Akiyama en-aut-mei=Yoshiko kn-aut-name=秋山佳子 kn-aut-sei=秋山 kn-aut-mei=佳子 aut-affil-num=3 ORCID= en-aut-name=KawasakiToshio en-aut-sei=Kawasaki en-aut-mei=Toshio kn-aut-name=河ｱ利夫 kn-aut-sei=河ｱ kn-aut-mei=利夫 aut-affil-num=4 ORCID= affil-num=1 en-affil= kn-affil=岡山大学 affil-num=2 en-affil= kn-affil=岡山大学 affil-num=3 en-affil= kn-affil=岡山大学 affil-num=4 en-affil= kn-affil=岡山大学 en-keyword=Barley kn-keyword=Barley en-keyword=Hydroponics kn-keyword=Hydroponics en-keyword=Mannose kn-keyword=Mannose en-keyword=Potassium kn-keyword=Potassium en-keyword=Phosphate kn-keyword=Phosphate END start-ver=1.4 cd-journal=joma no-vol=3 cd-vols= no-issue=2 article-no= start-page=117 end-page=127 dt-received= dt-revised= dt-accepted= dt-pub-year=1995 dt-pub=1995 dt-online= en-article= kn-article= en-subject= kn-subject= en-title=Differences in the Responses to Iron Deficiency Stress between Bean and Maize kn-title=インゲンとトウモロコシの鉄欠乏ストレスに対する反応の差異 en-subtitle= kn-subtitle= en-abstract=インゲンとトウモロコシを用い、鉄欠乏ストレスに対する両植物の反応の差異について検討した。その結果は以下のように要約できる。1)鉄欠乏ストレスに対して、インゲンの感受性は小さく、トウモロコシの感受性は大きかった。換言すれば、インゲンの鉄欠乏耐性は大きく、トウモロコシの鉄欠乏耐性は小さいということができる。2）鉄欠乏ストレスを受けたとき、インゲン根は鉄還元能と培地pH低下能を発現したが、トウモロコシ根ではそのような反応はほどんど認められなかった。3)鉄欠乏ストレスによるインゲン根での鉄還元能と培地pH低下能の発現は遮光処理、植物体地上部の切断処理、あるいは代謝阻害剤（DNP）の添加によって抑制された。4)鉄無添加処理はその後のインゲン植物体の鉄吸収を著しく促進した。トウモロコシではそのような現象は認められなかった。したがって、インゲンの鉄欠乏耐性が大きいのは、鉄欠乏ストレスによってインゲン根で鉄還元能と培地pH低下能が発現することによるものと考えられる。 kn-abstract=The responses to iron deficiency stress in bean and maize were compared. The susceptibility to iron deficiency stress was smaller in bean than in maize;i.e., the tolerance to iron deficiency was greater in bean than in maize. The roots of the bean plants exposed to iron deficiency stress, developed iron reducing capacity and medium-pH lowering capacity,but not the roots of maize. The iron reducing capacity and medium-pH lowering capacity of the bean roots were inhibited by a shadowing, detopping, and the addition of 2,4-dinitrophenol. Iron absorption in the bean plants was stimulated by the pretreatment without iron in the growth medium, but not in the maize plants. The finding suggest that the high tolerance of bean plants to iron deficiency stress is caused by the development of iron reducing capacity and medium-pH lowering capacity of the bean roots. en-copyright= kn-copyright= en-aut-name=YonetaniTsutomu en-aut-sei=Yonetani en-aut-mei=Tsutomu kn-aut-name=米谷力 kn-aut-sei=米谷 kn-aut-mei=力 aut-affil-num=1 ORCID= en-aut-name=MoritsuguMasumi en-aut-sei=Moritsugu en-aut-mei=Masumi kn-aut-name=森次益三 kn-aut-sei=森次 kn-aut-mei=益三 aut-affil-num=2 ORCID= en-aut-name=KawasakiToshio en-aut-sei=Kawasaki en-aut-mei=Toshio kn-aut-name=河ｱ利夫 kn-aut-sei=河ｱ kn-aut-mei=利夫 aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=岡山大学 affil-num=2 en-affil= kn-affil=岡山大学 affil-num=3 en-affil= kn-affil=岡山大学 en-keyword=Bean kn-keyword=Bean en-keyword=Iron deficiency stress kn-keyword=Iron deficiency stress en-keyword=Iron reducing capacity kn-keyword=Iron reducing capacity en-keyword=Maize kn-keyword=Maize en-keyword=Medium-pH lowering capacity kn-keyword=Medium-pH lowering capacity END start-ver=1.4 cd-journal=joma no-vol=3 cd-vols= no-issue=2 article-no= start-page=105 end-page=116 dt-received= dt-revised= dt-accepted= dt-pub-year=1995 dt-pub=1995 dt-online= en-article= kn-article= en-subject= kn-subject= en-title=Effect of Light Irradiation on the Absorption of Rubidium in Chlorella kn-title=クロレラのルビジウム吸収に対する光の影響 en-subtitle= kn-subtitle= en-abstract=クロレラのルビジウム吸収に対する光照射の影響について検討した。その結果、光照射によってルビジウム吸収が明らかに促進されることが認められた。各種代謝阻害剤による実験の結果から、明条件でのクロレラによるルビジウム吸収と酸素発生の両者に対して、DCMUの添加が最もよく一致した影響を示し、ルビジウム吸収の光促進効果と光合成過程との密接な関連が示唆された。 kn-abstract=The effect of light irradiation on the absorption of rubidium was examined in Chlorella. Rubidium absorption in Chlorella was clearly stimulated by the irradiation of light. To clarify the mechanism of light-stimulation on rubidium absorption, experiments were carried out using several metabolic inhibitors; DCMU, NaCN,DNP,CCCP and ouabain. Among the metabolic inhibitors used, DCMU had the most similar effects on the rubidium absorption and oxygen evolution under light condition. These findings suggest a close correlation between the light-stimulation on rubidium absorption and the photosynthetic process in Chlorella. en-copyright= kn-copyright= en-aut-name=HachiyaKinji en-aut-sei=Hachiya en-aut-mei=Kinji kn-aut-name=蜂谷欽司 kn-aut-sei=蜂谷 kn-aut-mei=欽司 aut-affil-num=1 ORCID= en-aut-name=MoritsuguMasumi en-aut-sei=Moritsugu en-aut-mei=Masumi kn-aut-name=森次益三 kn-aut-sei=森次 kn-aut-mei=益三 aut-affil-num=2 ORCID= en-aut-name=KawasakiToshio en-aut-sei=Kawasaki en-aut-mei=Toshio kn-aut-name=河ｱ利夫 kn-aut-sei=河ｱ kn-aut-mei=利夫 aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=岡山大学 affil-num=2 en-affil= kn-affil=岡山大学 affil-num=3 en-affil= kn-affil=岡山大学 en-keyword=Chlorella kn-keyword=Chlorella en-keyword=Light-stimulation kn-keyword=Light-stimulation en-keyword=Metabolic inhibitors kn-keyword=Metabolic inhibitors en-keyword=Oxygen evolution kn-keyword=Oxygen evolution en-keyword=Rubidium absorption kn-keyword=Rubidium absorption END start-ver=1.4 cd-journal=joma no-vol=3 cd-vols= no-issue=2 article-no= start-page=091 end-page=103 dt-received= dt-revised= dt-accepted= dt-pub-year=1995 dt-pub=1995 dt-online= en-article= kn-article= en-subject= kn-subject= en-title=数種植物におけるアンモニウムイオン及び硝酸イオンの吸収速度の比較 kn-title=Comparison of Absorption Rates between Ammonium and Nitrate Nitrogen in Plants en-subtitle= kn-subtitle= en-abstract=硝酸アンモニウム2.5mMの単塩溶液（以下、硝安単塩溶液）及び2.5mMの硝酸アンモニウムを窒素源とする完全培地（以下、硝安完全培地）を吸収溶液とし、アンモニア態窒素及び硝酸態窒素について24時間の吸収実験を行った。実験材料はイネ、オオムギ、レタス、キュウリ、ニンジン、ハクサイ、ホウレンソウ、ダイコンであった。硝安単塩溶液及び硝安完全培地における両形態窒素の吸収特性から、試験植物は次のように分類できた。（1）イネ、オオムギ、レタス：何れの吸収溶液からでも、硝酸態窒素に比較して常にアンモニア態窒素を速やかに吸収する植物群、（2）キュウリ、ニンジン：硝安単塩溶液ではアンモニア態窒素を速やかに吸収するが、硝安完全培地ではこの傾向が逆転し、硝酸態窒素の吸収がやや速やかになる植物群、（3）ハクサイ、ホウレンソウ、ダイコン：硝安単塩溶液では両形態の窒素の吸収速度はほぼ等しいが、硝安完全培地では明らかに硝酸態窒素の吸収が速やかになる植物群。上記の分類は、それぞれの培地におけるアンモニア態窒素の吸収と拮抗する他のイオンの吸収特性、換言すれば、NO3-/NH4+吸収比、あるいは、Ca2+とMg2+の合計吸収速度、または、植物根の硝酸態窒素に対する相対的な根の親和性、つまり、NO3-/H2PO4-吸収比によって説明できた。すなわち、第1群は1価陽イオン、特に、アンモニウムイオンに対する根の親和性は大きいが硝酸態窒素に対する根の親和性は小さく、また、耐酸性、耐アンモニア性の大きい植物と考えられ、24時間の吸収時間中の培地pHの低下は著しかった。これに対して、第3群は硝安完全培地中では硝酸態窒素、2価陽イオンに対する根の親和性の大きい植物であり、また第2群は、アンモニア態及び硝酸態窒素、ならびに、2価陽イオンに対する根の親和性などが第1群と第3群の中間の植物であった。 kn-abstract=Absorption rares of ammonium ion(NH4+) and nitrate ion(NO3-) for 24 hours were compared using two absorption solutions, which were a single salt solution of ammonium nitrate (NH4NO3) and a complete nutrient solution containing NH4NO3. Test plants were Oryza sativa (Rice), Hordeum vulgare (Barley), Lactuca sativa (Lettuce), Cucumis sativus (Cucumber), Daucus carota (Carrot), Brassica pekinesis (Chinese cabbage), Spinacia oleracea (Spinach) and Raphanus sativus (Radish). From the absorption characteristics of NH4+ and NO3- between a single salt solution of NH4NO3 and a complete nutrient solution containing NH4NO3, the test plants were classified into goup 1(rice,barley and lettuce), which absorbed NH4+ more rapidly than NO3- in both absorption solutions, group 2(cucumber and carrot), which absorbed NH4+ slightly more than NO3- in the single salt solution of NH4NO3, the tendency of which was reversed in the complete nutrient solution containing NH4NO3, and goup 3(Chinese cabbage,spinach and radish), which absorbed NO3- clealy more than NH4+ in the complete nutrient solution, whereas the absorption of NH4+ or NO3- was almost equal in the single salt solution of NH4+NO3-. The above classisication of plants could be explained by the balance of a repressive or competitive characteristics of NH4+ absorption mainly as sociated with a capacity for absorption of calcium ion(Ca2+) and magnesium ion(Mg2+), and the relative root affinity to NO3- that can be evaluated by the relative absorption of NO3- to mono-phosphate ion(H2PO4-) in plant roots. The group 1 plants are the so-called acid tolerant plants, which appeared to be tolerant to NH4+, and showed a marked pH decreased during the 24 hours of the absorption experiments in those plants. By contrast, the group 3 plant seemed to prefer NO3- and divalent alkaline earth cations to the other nutrients in the complete nutrient solution containing NH4No3, and the pH decrease during each absorption experiment was small. en-copyright= kn-copyright= en-aut-name=MoritsuguMasumi en-aut-sei=Moritsugu en-aut-mei=Masumi kn-aut-name=森次益三 kn-aut-sei=森次 kn-aut-mei=益三 aut-affil-num=1 ORCID= en-aut-name=KawasakiToshio en-aut-sei=Kawasaki en-aut-mei=Toshio kn-aut-name=河ｱ利夫 kn-aut-sei=河ｱ kn-aut-mei=利夫 aut-affil-num=2 ORCID= en-aut-name=SuzukiTakao en-aut-sei=Suzuki en-aut-mei=Takao kn-aut-name=鈴木孝夫 kn-aut-sei=鈴木 kn-aut-mei=孝夫 aut-affil-num=3 ORCID= affil-num=1 en-affil= kn-affil=岡山大学 affil-num=2 en-affil= kn-affil=岡山大学 affil-num=3 en-affil= kn-affil=岡山大学 en-keyword=Alkaline earth kn-keyword=Alkaline earth en-keyword=Ammonium kn-keyword=Ammonium en-keyword=Ion balance kn-keyword=Ion balance en-keyword=Nitrate kn-keyword=Nitrate en-keyword=Phosphate kn-keyword=Phosphate END