Abstract:Effects of different tillage practices, i.e. T, NT and NTS, on soil microbes and soil enzyme activities are studied in wheat herb (Isatis indigotica Fort) rotations. The results show that conservation tillage improves soil enzyme activities in 0-5cm,5-10cm and 10-30cm layer after wheat herb rotation and NTS has the best effect. Compared with T, activities of urease, alkaline phosphatase and invertase of topsoil under NTS have increased by 38.53%, 39.65% and 110.00% respectively in herb soil, and by 28.10%,19.71% and 75.00% in wheat soil in respective. NTS has the biggest effect on invertase activity of topsoil, but the catalase activity of 10-30cm layer soil has increased most obviously. After wheat herb rotations, NTS has resulted in the biggest numbers of bacteria, fungi, and microbes at each layer in herb soil, followed by NT and T. In wheat soil, tillage practices have similar effects on soil microbes, except that soil in 10-30cm under NT has the biggest numbers of bacteria, fungi, and the largest total amount of microbes. In herb soil, the numbers of bacteria, fungi, invertase, and the total amount of microbes at 0-5cm under NTS are 22.81%, 55.56%, 6714% and 22.81% higher than those under T in respective, while in wheat soil, these indicators have been improved by 6284%, 92.86%, 14.29%, and 66.67% under T upon those under NTS. The numbers of bacteria and the total amount of microbes in herb soil have decreased by 10 times compared with those in wheat soil.