| Improved soil DNA extraction method was used to extract the whole microbial genome directly from the corn farmland soil samples, the diversity of bacterial community was studied by amplifying the bacterial 16S rDNAV3 fragment with nested and touch-down PCR methods, and separating the products by denaturing gradient gel electrophoresis (DGGE). Soil samples were taken at three different depths within four different stages. The result shown that the improved extraction method and PCR strategies was efficient, the diversity of soil bacteria was higher in maize fields. With the change of the maize growth and soil depth, the bacterial populations shown highly diverse in species but the dominants species community were stable. The most obvious community changed in the bacterial community in the period of maize seedlings and filling stage, with the most abundant species of bacteria during this period. The least types of bacteria were isolated after the harvest. There was an obviously different of soil bacteria community under different depths in the same growth period of maize 渊the soil bacteria distribution under different depths were different in the same growth period of
maize冤袁and the number of bacteria community in top soil changed more greatly than others. |
