Studies on some parameters that may influence the uptake of radioisotopes by plants from the soil

Abstract

The objective of this study was to identify some plant species that show higher nutrient uptake ability than others, and to explore the possibility of improving their uptake ability still further by the following methods: (1) Soil improvements by varying pH conditions, nutrient mineral content, organic matter content, etc.; and (2) Introduction of some soilborne non-pathogenic fungal and bacterial species. As the first step of this project, several plants were tested for their relative uptake capabilities using multitracer as the source of radioisotopes. Those plants were: turnip (Brassica campestris L.ssp. rapa), Chinese cabbage (Brassica campestris L. ssp. pekinensis), soybean (Glycine max), black mungbean (Vigna radiata) and maize (Zea mays). An appropriate amount of Cs-137 was added to the multitracer solution and the concentration of the resulting solution was diluted to a desired concentration with water. The solution was supplied to the soil in which seeds were sown. After growing for thirty days, the uptake of radioisotopes in question was detected using a Ge detector.

他よりも取込能力に優れている植物種を特定し、更に取込能力を延ばす可能性を以下の方法で調査した。(1)pH条件、栄養ミネラル含有量、有機物含有量などの変化による土壌の改良、および(2)ある種の土壌伝染性で非病原性の菌類種およびバクテリア種の導入。プロジェクトの第1段階として、放射性同位元素の線源としてマルチトレーサを用いて、カブ(Brassica campestris)、中国キャベツ(B. campestris)、大豆(Glycine max)、黒ヤエナリ(Vigna radiata)、トウモロコシ(Zea maize)などの植物について相対的な取込み能力を調べた。適量のCs-137をマルチトレーサ溶液に加え希釈水で任意の濃度にして種を植えた土壌に注いだ。30日間成長させた後、注目した放射性同位元素の取込みをGe検出器を使用して測定した。