[Effect of adding different amounts of wheat straw and phosphorus on soil microorganism community].

A pot experiment was conducted to study the effects of adding different amounts of wheat straw (0 g x kg(-1), N0; 2.08 g x kg(-1), N1) and phosphorus (0 mg x kg(-1), P0; 100 mg x kg(-1), P1; 200 mg x kg(-1), P2; 400 mg x kg(-1), P3) on microorganism community in a soil of low-phosphorus. Adding straw and phosphorus had significant effects on the soil microbial total biomass (MTB), bacterial biomass (MB), fungal biomass (FB), and fungi to bacteria ratio (F/B), which all decreased in order of N1P1>N1P0>N1P2>N1P3>N0P1>N0P2>N0P3. MTB, MB, FB and F/B ratio of the wheat straw addition treatments were all significantly higher than in the non-straw addition treatments under the same level of phosphorus addition. As for the same wheat straw addition, MTB, MB, FB and F/B ratio increased firstly and then decreased with increasing the level of phosphorus addition, and the combinations of P1 level were optimal.