Description:
<jats:title>ABSTRACT</jats:title>
<jats:p>
Two soils were amended three times with pig manure. The abundance of sulfonamide resistance genes was determined by quantitative PCR 2 months after each application. In both soils treated with sulfadiazine-containing manure, the numbers of copies of
<jats:italic>sul1</jats:italic>
and
<jats:italic>sul2</jats:italic>
significantly increased compared to numbers after treatments with antibiotic-free manure or a control and accumulated with repeated applications.
</jats:p>