Abstract: In order to clarify the mitigation effect of different control measures on continuous cropping obstacle of sorghum,three treatments which were continuous sorghum cropping treatment(T1),applying biological agent on continuous sorghum cropping(T2),sorghum/corn rotation(T3) were conducted using pot experiment, and the effects of different control measures on the growth, microbial functional diversity and Shannon index of bacteria and fungi in sorghum rhizosphere soil were studied.The results showed that applying biological agent and sorghum/corn rotation could promote the growth of sorghum.The plant height,stem diameter and biomass of sorghum with biological agent increased by 16.95%,13.33% and 19.82% compared with continuous cropping treatment,respectively.The stem diameter and biomass of sorghum/corn rotation treatment increased by 12.00% and 16.22% compared with continuous cropping treatment,respectively.The utilization of carbon sources by the sorghum rhizosphere soil microbial community showed that,the average well color development(AWCD) value of sorghum/corn rotation treatment was the highest,which was 16. 72% higher than that of continuous cropping treatment and 19.15% higher than that of applying biological agent treatment,at 96 h after culture,respectively.The result indicated that applying biological agent and sorghum/corn rotation both increased the carbon source utilization capacity of sorghum rhizosphere soil microbial community.The DGGE maps of bacteria and fungi were analyzed,the results showed that there were abundant bacterial bands in the rhizosphere soil of sorghum,and the number and brightness of bands varied among different treatments. Shannon index of rhizosphere soil bacterial community of sorghum/corn rotation treatment was significantly higher than that of continuous cropping treatment.There was an obvious difference in the number of bands of fungus 18S.Specific bands were found in continuous cropping and applying biological agent treatments,indicating that the fungi gene Shannon index in 18S zone was higher in the rhizosphere soil of continuous sorghum.Applying biological agent and sorghum/corn rotation could alleviate the continuous cropping obstacles of sorghum to a certain extent, it should be noted that the effect of applying biological agent to continuous cropping soil had the best effect.

Key words: Sorghum, Continuous cropping obstacle, Rotation, Biolog-Eco, DGGE, Rhizosphere soil, Microbial community, Biological agent

摘要： 为了明确不同调控措施对高粱连作障碍的缓解作用，采用盆栽试验，设置了高粱连作（T1）、高粱连作施加生态调理剂（T2）、高粱/玉米轮作（T3）3个处理，探究不同调控措施对高粱生长、高粱根际土壤微生物群落功能多样性、细菌和真菌的基因香农指数的影响。结果表明，施加生态调理剂和高粱/玉米轮作都可促进高粱生长，施加生态调理剂高粱的株高、茎粗和干物质量分别比连作显著增加16.95%、13.33%和19.82%，高粱/玉米轮作高粱的茎粗、生物量分别比连作显著增加12.00%、16.22%。高粱根际土壤微生物群落对碳源的利用能力表现出：高粱/玉米轮作土壤的平均颜色变化率（AWCD）最高，在培养96 h时比连作、施加生态调理剂处理分别高出16.72%、19.15%（P<0.05），施加生态调理剂和高粱/玉米轮作处理均增加了高粱根际土壤微生物群落的碳源利用能力。对细菌、真菌的DGGE图谱进行分析，结果显示，高粱根际土壤中细菌条带较为丰富，不同处理在条带数量及条带亮度上有所差别，高粱/玉米轮作处理的根际土壤细菌群落的香农指数显著高于连作处理，真菌18S在条带数量上有明显差别，连作、施加生态调理剂处理都出现特异性条带，这表明在连作高粱根际土壤中真菌18S区的基因香农指数较高。施加生态调理剂和与高粱/玉米轮作都可在一定程度上缓解高粱连作障碍，施加生态调理剂效果最佳。

关键词: 高粱, 连作障碍, 轮作, Biolog-Eco, 变形梯度凝胶电泳, 根际土壤, 微生物群落, 生态调节剂