Abstract:

【Objective】The objective of the study is to evaluate the community structure and diversity of nitrobacteria community in rhizosphere and non-rhizosphere soils at tobacco mature stage. 【Method】Five tobacco rhizosphere soil samples and five non-rhizosphere soil samples were collected from the main tobacco-producing areas of Panzhihua Yanbian County and analyzed by PCR-DGGE technology. 【Result】DGGE analysis showed that nitrobacteria community structure and diversity were different among different soils. Overall, the rhizosphere diversity index (H), abundance (S) and evenness (EH) were not all higher than those of non-rhizosphere soil, which might be related to rhizosphere secretion at tobacco mature stage which had an inhibitory effect on nitrobacteria. Moreover, the nitrobacteria community structures in different soil samples had a great difference. The recovery DGGE strip series showed that most of them were similar to Nitrospira sp. of the extreme environment such as glacier, or dissolution rock, while small of them were closely related to uncultivated nitrobacteria.【Conclusion】The diversity of nitrobacteria in the mature tobacco rhizosphere soils was higher than that of non-rhizsphere soils.