Rhizosphere bacterial community can promote the nutrition absorption of plant root, which result in the upgrade of plant quality.Cultivation system has effect on rhizosphere bacterial community. Four treatments were set to investigate the effects of two different cultivation systems, soil and substrate systems, for two varieties of lettuce, Shengxuan NO.5 and cv. Lollo Rossca.(two cultivation systems × two varieties). Each treatment had three pots as samples with 10 lettuce plants for each pot. After 30 day...