報告書番号

U89014

タイトル（和文）

水耕栽培ホウレンソウの生育におよぼす亜鉛の影響

タイトル（英文）

EFFECT OF ZINC CONCENTRATION ON THE GROWTH OF SPINACH GROWN IN NUTRIENT SOLUTION

概要 （図表や脚注は「報告書全文」に掲載しております）

ホウレンソウの生育におよぼす水耕培養液のＺｎ濃度の影響と，Ｚｎ過剰に対するＦｅの抑制効果の程度，およびこれらの要因と植物体の元素含有量との関係について検討した。純水を用いて，Ｆｅ濃度が１ｍｇ／ｌでは，Ｚｎ濃度が０．５ｍｇ／ｌ以上になると，根が褐色になり，伸長生長も抑制され，２ｍｇ／ｌでは地上部は黄化した。培養液のＦｅ濃度が２ｍｇ／ｌ以上になると，Ｚｎ濃度が２ｍｇ／ｌでも地上部の黄化症状は観察されなくなった。培養液のＺｎ濃度に比例して，植物体のＺｎ含有量は指数的に高くなったが，培養液のＺｎ濃度が同じでも，Ｆｅ濃度が高くなると，Ｚｎ含有量のレベルは低下した。植物体のＺｎ含有量が顕著に高くなり始める約２００μｇ／ｇ条が影響発現の限界Ｚｎ含有量（下限値）と推定された。本実験から，ホウレンソウの水耕培養液のＦｅ濃度は２～５ｍｇ／ｌ，Ｚｎは０．１ｍｇ／ｌ以下の濃度が維持できれば良いと考えられた。

概要 （英文）

SPINACH WAS GROWN IN NUTRIENT SOLUTION AT THE DIFFERENT ZN CONCENTRATION WITH DIFFERENT FE CONCENTRATION. PLANT TOPS DID NOT SHOW CLEAR ZN-DEFICIENCY SYMPTOMS AT NO ADDITION OF ZN TO THESOLUTION. ZINC CONCENTRATION EXCEEDING 0.5 MG/L AT 1 MG FE/L INHIBITEDPLANT GROWTH. PLANT TOPS AT 2 MG ZN/L AT 1 MG FE/L SHOWED INTERVEINAL CHLOROSIS AS A ZN-TOXICITY,HOWEVER,INCREASED FE CONCENTRATION PREVENTEDSUCH TOXIC SYMPTOMS. ZINC CONTENT IN PLANT GROWN IN ZINC DEFICIENT SOLUTION WAS 16 UG/G IN TOPS OR 20 UG/G IN ROOTS. THAT IN PLANTS GROWN AT 0.01 MG/L OF ZN WITH 1 MG/L OF FE,WAS 55UG/G FOR TOPS OR 34 UG/G FOR ROOTS. IT INCREASED EXPONENTIALLY WITH INCREASING ZN CONCENTRATION. HOWEVER,INCREASED FE CONCENTRATION IN NUTRIENT SOLUTION REDUCED TISSUE ZN CONTENTS. THE ZN CONTENT: 200 UG/G,WOULD BE A LOWER POTENTIAL TOXIC BORDERLINE. IRON CONTENTS IN NORMAL TOPS WERE MORE THAN 50 UG/G,HOWEVER,THOSE SHOWING INTERVEINAL CHLOROSIS DUE TO EXCESSIVE ZN WERE LESS THAN 40 UG/G. IRON CONTENTS IN ROOTS INCREASED WITH INCREASING FE CONCENTRATION IN THE NUTRIENT,HOWEVER,THOSE IN TOPS DID NOT. IN CONTRAST,INCREASED ZNCONCENTRATION IN THE SOLUTION INCREASED FE CONTENT IN THE ROOTS,BUT DECREASED THAT IN THE TOPS. THUS,THESE RESULTS SUGGESTED THAT INTERVEINALCHLOROSIS IN PLANT TOPS WAS A TYPICAL FE DEFICIENCY WHICH WAS INDUCED BY EXCESSIVE ZN IN THE SOLUTION. MANGANESE CONTENTS IN PLANT TOPS INCREASED WITH INCREASING ZN CONCENTRATION IN THE SOLUTION,HOWEVER,INCREASEDFE CONCENTRATION DECREASED MN CONTENTS IN THE TOPS. CURRENT EXPERIMENTAL RESULTS SUGGEST THAT ZN DEFICIENCY IS NOT LIKELY TO OCCUR IN NORMAL NUTRIENT SOLUTION CULTURE FOR SPINACH. CONCENTRATION OF ZN AND FE IN THE NUTRIENT SOLULD SHOULD BE MAINTAINED AT THE CONCENTRATION LESS THAN 0.1 MG/L OF ZN AND IN THE RANGE OF 2 - 5 MG/L OF FE FOR SPINACH CULTIVATION.

報告者

キーワード