Abstract: This paper summarizes the researches abroad on conjugated and bound residues of pesticides. The conjugated or bound residues of pesticide, in the environmental sense, have varied biological effects. Their behaviors in environment are different from those of unconjugated or un-bound parent molecules or residues. By conjugation or binding, some of the pesticide molecules are activated, others are decreased by biological activities. According to these, the speciality of pesticide persistence in soil is re-evaluated.

Key words: transgenic Bt rice variety, soil ecosystem, dissolved organic carbon and nitrogen, microbiological properties