摘要： 为了探究芸豆根际微生态环境对盐胁迫的响应机制，以HYD和JW为试验材料，采用盆栽法，将2种碱性盐Na₂CO₃、NaHCO₃按摩尔比1：9混合，按混合后占土壤质量分数0（S0），0.4%（S1），0.8%（S2），1.2%（S3）设计4个浓度梯度，研究不同程度盐碱胁迫对芸豆根际土壤微生物数量和土壤酶活性的影响。结果表明，在盐碱胁迫下，HYD在株高、根长和地上、下生物量等优于JW。在盐碱胁迫处理下根际土壤细菌、真菌和放线菌数量差异显著，细菌数量高于真菌和放线菌数量。两芸豆品种根际土壤脲酶、磷酸酶、过氧化氢酶活性与土壤微生物数量均在S1处理下达到最大值，且差异显著。在相同处理下，HYD的株高、根长和地上、地下生物量等生长特性与根际土壤微生物数量、酶活性均显著高于JW。相关分析表明，脲酶活性与细菌数量、真菌数量、放线菌数量和微生物总量呈显著或极显著正相关，磷酸酶活性与放线菌数量、过氧化氢酶活性与真菌数量均呈显著正相关。在盐碱胁迫条件下，pH值上升，微生物数量发生变化，导致酶活性改变，间接改变根际土壤微环境。一定量的盐碱胁迫有利于提高芸豆根际土壤微生物数量及酶活性，促进芸豆生长。

关键词: 芸豆, 盐碱胁迫, 根际, 土壤微生物, 土壤酶活性

Abstract: A pot experiment was conducted to study the effects of salinity-alkalinity stress on rhizosphere microecological environment of two common bean varieties, HYD and JW. Two kinds of alkaline salts(Na₂CO₃, NaHCO₃) were mixed together in the proportion of 1:9. According to the percentage of soil mass after mixing, four treatments of 0(S0), 0.4%(S1), 0.8%(S2)and 1.2%(S3)were set to investigate the effects of different treatments on rhizosphere soil microbial quantity and enzyme activity. The results showed that under salt-alkali stress, HYD was better than JW in plant height, root length, shoot biomass and root biomass. There was a significant difference in the number of bacteria, fungi and actinomycetes in rhizosphere soil under saline-alkali stress treatments, and the number of bacteria was higher than those of fungi and actinomycetes. The soil urease, phosphatase, catalase activity and soil microbial quantity in rhizosphere of two common bean cultivars were the maximum in S1 treatment, reaching to a significant difference. Under the same treatment, the growth characteristics of plant height, root length,shoot biomass and root biomass of HYD were significantly higher than those of JW. The number of microorganisms and enzyme activity in the rhizosphere soil of HYD were significantly higher than those of JW. Correlation analysis showed that urease activity had significantly or extremely significantly positive correlation with the numbers of bacteria, fungi and actinomycetes, and total amount of microorganisms, while there was significantly positive correlation between phosphatase activity and the number of actinomycetes and between catalase activity and the number of fungi. Under salinity-alkalinity stress, the soil pH rose and microbial population changed, which led to changes in enzyme activity and indirected changes in rhizosphere soil microenvironment. A certain amount of salinity-alkalinity stress is beneficial to the improvement of soil microorganism and enzyme activity in common bean rhizosphere. A certain amount of saline-alkali stress promotes the growth of common bean.

Key words: Common bean, Salinity-alkalinity stress, Rhizosphere, Microbial quantity, Soil enzyme

中图分类号: 

• S144