Dynamics of selenium in agricultural ecosysytem

研究了农业生态系统中硒的动态变化。有机硒采用含硒蛋氨酸和含硒半胱氨酸酵母。亚硒酸盐作为无机硒。将这些硒化合物施用于土壤中，种植小松。亚硒酸盐中含有蛋氨酸硒、亚硒酸盐和硒酸盐，土壤中的硒以亚硒酸盐为主。这说明亚硒酸盐在土壤中不发生变化，被植物吸收后形成硒酸盐和硒-蛋氨酸。另一方面，施用酵母的土壤中硒以亚硒酸盐为主，收获后未发现硒-蛋氨酸和硒-系统氨酸。小松含有的硒化合物与应用小松的亚硒酸盐相同。这些事实可能说明硒半胱氨酸和硒蛋氨酸因矿化而消失，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.