Abstract:
Field trials on six successive crops of Brassica parachinensis (BP) were conducted to investigate the influence of organic fertilizer application pattern on the BP yield, and soil chemical property and micro-organism under intensive vegetables cultivation in Guangzhou. The organic fertilizer application patterns include application of inorganic fertilizer (CK), combined application of inorganic and organic fertilizers (BM), combined application of inorganic fertilizer and humic acid (HA), combined application of inorganic fertilizer and sprinkled
Bacillus sp. (BSP), combined application of inorganic fertilizer, humic acid and sprinkled
Bacillus sp. (HA+BSP), combined application of inorganic fertilizer, decomposed chicken manure and sprinkled
Bacillus sp. (CM+BSP), and combined application of inorganic fertilizer and
Bacillus sp. retted chicken manure (BSPCM). The results show significant variations in mean yields among different crops. Among all the treatments in six crops, CM+BSP treatment yields the highest BP, followed by BSPCM treatment (both of which are significantly higher than the CK). BM, CM+BSP and BSPCM treatments can increase soil pH reducing the risk for soil acidification of intensive vegetable land. The number of soil bacteria, fungi and total micro-organisms under CM+BSP increases with increasing of cropping times, which is significantly higher than those under the initial soil and other treatments. Next in a similar trend is BSPCM treatment. The number of soil bacteria, fungi and total micro-organisms decreases under CK compared with initial soil condition. Hence for continuous vegetable cultivation, in different combinations with chicken manure, inorganic fertilizer plus sprinkled Bacillus sp. increases yield and soil fertility, activates soil biological properties, and reduces risks of continuous vegetables cropping obstacle. This method could therefore be used to realize sustainable development of intensive vegetable production in Guangzhou.