除草劑가 밭土壤 및 고추連作地土壤의 微生物相의 菌數變化와 酵素活性에 미치는 影響을 調査하여 얻은 結果는 다음과 같다. 微生物의 數는 Pythium屬菌을 除外한 Actinomycetes, Bacteria, Fungi 및 Fusarium 屬菌의 경우 藥劑處理에 의해 一般約으로 減少하다가 30日경부터는 對照區와 비슷한 水準이었다. 특히 fungi는 2∼10日에 약 7倍의 현저한 減少를 보였고 Actinomycetes는 Linuron處理時 20日에 對照區보다 增加하였다. 한편 Pythium 屬菌은 初期부터 菌數가 增加하는 傾向이었다. 酵素活性은 時日이 經過함에 따라 活性이 減少하는 傾向이었으나 Urease와 Phosphatase는 MO, Linuron 및 Simetryne 處理時 6日 및 10日에 對照區보다 높은 活性을 보이고 Protease는 Simetryne處理區에서 높은 活性을 보였으나 30日以後에는 급격히 減少하였다. β-Glucosidase 및 Polygalacturonase活性은 除草劑에 의해 별 影響이 없었고 Cellulase活性은 初期에는 沮害를 받다가 20日以後에는 回複되어 對照區보다 높은 活性을 보였다. Fungi를 除外한 微生物菌數와 呼吸量과의 關係는 5% 水準에서 有意性있는 相關을 나타냈으며, Linuron을 處理時 全土壤微生物 菌數와 呼吸量과의 關係는 高度의 有意性을 나타냈다. 全土壤微生物 菌數와 5種의 酵素活性과의 關係는 一般的으로 Protease活性과 가장 높은 相關을 나타냈으며, Polygalact uronase와 β-Glucosidase活性과는 有意性이 없었다. 特히 Dicamba와 Simetryne의 處理時 Protease와 Urease活性과의 關係에서 5㎍/g濃度의 Simetryne과 Urease와의 關係를 除外하고 高度의 有意性이 認定되었다.

This study was conducted to find out the effect of herbicides on soil micro-organism and soil enzyme in loam soil, and on pathogenic microorganism in continuous pepper cropping soil. The result was summarized as follows: When herbicides were treated, the number of soil microorganism generally decreased at the early stage of incubation, and gradually increased at 30 days incubation. The number of fungi was significantly decreased seven times comparison with control plot. The number of actinomycetes was increased at 20 days incubation and that of pytium was increased for all days incubation in Linuron treatment plot. Although the activity of soil enzyme tended to decrease when herbicides were treated, the activities of urease and phosphatase were higher than that of control plot at the early stage of incubation in MO, Linuron and Simetryne treatment plot. In Simetryne treatment plot, the activity of protease was increased at the early stage, and suddenly decreased after 30 days incubation. There was no significant effect of herbicides on the activities of β-glucosidase and polygalacturonase. The activity of cellulase was inhibited at the early stage of incubation, but that of cellulase was higher than that of control plot after 20 days incubation. High significance was showed the correlation coefficient between soil microorganisms except fungi and soil respiration as herbicides were treated, and the total microorganism and soil respiration in Linuron plot. when Dicamba and Simetryne were treated, the correlation coefficient between the total microorganism and the activities of protease and urease were considerably significant.