MICROBIAL COMMUNITY STUCTURE IN PADDY SOIL
PVC columns with 16 cm diameter and 50 cmheight were used in the experiment. Each column waspacked first with 4.5 kg subsurface soil and 4.5 kg surfacesoil. The surface soil was mixed with the basalfertilizers as designed before packing. Before transplanting,
all PVC column pots were irrigated threedays for pre-incubation. Twenty-five-day rice seedlingswere transplanted at the center of the pot on July 3,with each pot containing two seedlings. The rice plantsin each pot were harvested on October 15, 2009. After
harvest, the dry weights of straw and grain yield were
measured. The concentration of N in the plant samples
was determined using the Kjedahl method.