关键词: 农业, 农业, 气象灾害, 食用杏, 产量, 影响评估

Abstract: The aim is to study the effects of straw returning combined with nitrogen fertilizer on paddy soil bacterial community diversity. Different treatments in field were set as following: gradient amount of nitrogen fertilizer (U), straw returning combined with gradient amount of nitrogen fertilizer (SU), no straw return and no nitrogen fertilizer as the control. The soil bacterial community structure, diversity index and richness index of different treatments in different rice growing stages were analyzed and compared by using PCR-DGGE cloning and sequencing technology. The results showed that the diversity index and richness index of SU treatment were higher than that of U treatment at seedling stage, tillering stage and elongation stage. On the contrast, these indexes of SU treatment were lower than that of U treatment at filling stage and maturation stage. With the nitrogen fertilizer increasing, the diversity index and richness index of SU and U treatments showed different trends, however the evenness index showed no significant variation. Meanwhile, through DGGE fingerprint analysis, the specific bands appeared at the tillering stage, filling stage and maturity stage were mainly identified as Sphingomonas belonging to Proteobacteria, Streptomyces sp. belonging to Actinobacteria, Comamonadaceae belonging to Betaproteobacteria, Sphingomonadaceae belonging to Alphaproteobacteria, Acidobacteria, Methylomonadaceae, Epsilonproteobacteria, Nitrospira and Firmicutes, etc.