Soil bacterial diversity was measured
DNA was extracted from soil samples using a DNA kit (MN NudeoSpin 96     Soi) and the concentration was determined using NanoDrop 2000. The PCR reaction     conditions were as follows: pre-denaturation at 94 for 5 min; 30 cycles of 94 for 30     s, 50 for 30 s and 72 for 66 s.