Dynamics of selenium in agricultural ecosysytem

研究了硒在农业生态系统中的动态。作为有机硒，使用含硒蛋氨酸和含硒半胱氨酸的酵母。作为无机硒，使用亚硒酸盐。将这些硒化合物施于土壤中，并种植小松菜。施硒小松菜含有硒蛋氨酸、亚硒酸盐和硒酸盐，土壤中的硒主要是亚硒酸盐。这说明硒在土壤中不发生变化，经植物吸收后，形成了硒酸盐和硒代蛋氨酸，而酵母施入土壤中的硒主要为亚硒酸盐，收获后未发现硒代蛋氨酸和硒代系统素。小松含有相同的硒化合物亚硒酸盐适用小松。这些事实可能表明硒代半胱氨酸和硒代蛋氨酸由于矿化作用而消失，并以亚硒酸盐的形式存在。

Dynamics of selenium in agricultural ecosystem were investigated. As organic selenium, seleno-methionine and seleno-cysteine cotaining yeast were used. As inorganic selenium, selenite were used. These selenium compounds were applied to soil and Komatuna were grown.Selenite applied Komatsuna contained seleno-methionine, selenite and selenate, and selenium in soil was mostly selenite. This shows selenite do not change in soil and after absoption by plant, selenate and seleno-methionine was formed.On the other hand, selenium in yeast applied soil was mostly selenite, and no seleno-methionine and seleno-systeine were found after harvest. Komatsuna contained the same selenium compound as selenite applied Komatsuna. These facts may show seleno-cysteine and seleno-methionine were disappeared due to mineralization and existed as selenite.