不同质地土壤玉米根际生物活性研究

【目的】明确不同质地土壤（砂壤、中壤、重壤）玉米生育期间根际微生物（细菌、放线菌、真菌）数量与酶（脲酶、蛋白酶、磷酸酶、转化酶、过氧化氢酶）活性的变化。【方法】采用池栽方式，以掖单22为材料，研究不同质地土壤的玉米根际微生物数量和酶活性变化，并进行相关分析。【结果】玉米播种前，砂壤中的微生物数量最多，重壤中最少；重壤中的酶活性最高，砂壤最低。3种土壤玉米根际生物活性的动态变化呈抛物线，吐丝期达最大值，此后逐渐下降。吐丝期，3种质地土壤玉米根际微生物数量均表现为中壤最多，重壤最少；5种酶活性均表现为中壤最大，砂壤最小。成熟期，玉米根际土壤细菌与放线菌表现为中壤中数量最多，重壤最少，真菌则表现为中壤最多，砂壤最少; 过氧化氢酶活性表现为重壤最高，砂壤最低，脲酶、蛋白酶、磷酸酶、转化酶表现为中壤中活性最高，砂壤最低。【结论】玉米根际生物活性受玉米生长发育进程和土壤质地的双重影响。

Effect of Different Textural Soils on Rhizosphere Microorganisms and Enzyme Activities in Maize

Abstract: The number of 3 rhizosphere microorganisms(bacteria, fungi, actinomycete) and 5 enzyme(catalase, proteasee ,urease, phosphatase,invertase) activities were studied during the whole life of corn plant in the sandy loam, loam and clay soil textures in the condition of pond culture.The main results are as follows: before seeding,the number of microorganisms in sandy loam was largest and smallest in clay.Enzyme activities in clay was highest and lowest in sandy loam. The dynamic change of rhizosphere microorganisms and enzyme activities in the 3 soil textures both turned on a parabola,with the peak in the silking stage,and then reducing gradually.In silking stage,the number of the 3 microorganisms was largest in loan and smallest in clay;and the 5 enzyme activites was highest in loam and lowest in sandy loam.At maturity,the number of bacteria and actinomycete was largest in loam and smallest in clay,while the number of fungi was largest in loam and smallest in sandy loam.The catalase activities was highest in clay and lowest in sandy loam,while the rest four were all highest in loam and lowest in sandy loam.In conclusion,the number of rhizosphere microorganisms and enzyme activities were affected by both the development of corn and soil texture.