不同栽培模式对黄瓜根际土壤酶活性及细菌群落结构的影响

分别以小麦、燕麦、毛葱、芹菜、白菜与黄瓜伴生或套作，研究了不同栽培模式对黄瓜根际土壤酶活性及细菌群落结构的影响，为连作土壤环境修复提供理论依据。结果表明:小麦/黄瓜、燕麦/黄瓜伴生，毛葱/黄瓜套作显著提高了根际土壤过氧化氢酶活性（P0.05）；芹菜/黄瓜套作和小麦/黄瓜伴生显著提高了根际土壤过氧化物酶活性（P0.05）；芹菜/黄瓜套作显著提高了根际土壤脲酶活性（P0.05）；不同栽培模式均显著提高了各时期根际土壤转化酶活性（P0.05）。PCR-DGGE分析结果显示，不同栽培模式在一定程度上提高了黄瓜根际土壤细菌群落结构多样性。DGGE条带测序显示，黄瓜根际土壤细菌大多与不可培养的细菌种属具有较高的同源性，测序比对推测，主要分属于-变形菌纲（Alphaproteobacteria）、-变形菌纲（Betaproteobacteria）、鞘脂杆菌纲（Sphingobacteria）和芽单胞菌纲（Gemmatimonadetes）四个纲。本研究说明不同栽培模式对土壤酶活性和土壤细菌群落结构均产生一定影响，改变了土壤环境，其中小麦与黄瓜伴生栽培模式效果较好。

Effects of cultivation modes on soil enzyme activities and bacterial community structures in the cucumber rhizosphere

To solve the problem of soil degradation with the increase of continuous cropping years,changes of rhizosphere soil enzyme activities and bacterial community structures under different cultivation modes were studied.The cultivation modes(accompany and intercropping) were set up with cucumber as the main crop.Wheat and oats were accompanied with cucumber,respectively,and Chinese onion,Chinese cabbage and celery were intercropped with cucumber,respectively.The results suggest that the soil catalase activities are increased when cucumber is cultivated with wheat,oats and Chinese onion,the soil urease activities are increased under the celery treatment,and the soil invertase activities are increased significantly in all cultivation modes.The results of the cloning and sequencing of DGGE bands amplified from cucumber rhizospheric soil samples show a high homology to uncultured bacterial species.The bands in cucumber rhizosphere soil are affiliated with Alphaproteobacteria,Betaproteobacteria,Sphingobacteria and Gemmatimonadetes.This study shows that soil enzyme activities and soil bacterial community structures are influenced by different cultivation modes,the soil environment is influenced by the cultivation modes,and the accompanied with wheat is a better mode of cucumber.