促进欧美I-107杨生长并提高根际土壤微生物多样性的适宜根剪位置  

Optimum root pruning position for microbial diversity in rhizosphere and growth of Populus euramericana cv. ‘Neva'

作　　者：井大炜 王明友 马海林[3] 杜振宇[3] 刘方春[3] JING Da-wei;WANG Ming-you;MA Hai-lin;DU Zhen-yu;LIU Fang-chun(College of Resources Environment and Planning, Dezhou University, Dezhou, Shandong 253023, China;College of Ecology and Garden Architecture, Dezhou University, Dezhou, Shandong 253023, China;Shandong Forestry Academy, Jinan, Shandong 250014, China)

机构地区：[1]德州学院资源环境与规划学院,山东德州253023 [2]德州学院生态与园林建筑学院,山东德州253023 [3]山东省林业科学研究院,济南250014

出　　处：《植物营养与肥料学报》2018年第3期833-840,共8页Journal of Plant Nutrition and Fertilizers

基　　金：国家自然科学基金项目(31500513);山东省农业重大应用技术创新课题"杨树超高产栽培关键技术研究";山东省科技发展计划项目(2010GSF10621)资助

摘　　要：【目的】探讨根剪位置对欧美I-107杨根际土壤微生物学特性和生长的影响,为欧美I-107杨高产栽培提供理论依据。【方法】试验于2014年4月开始,通过连续3年大田试验,以不进行根剪的树为对照(CK),设距离杨树干6倍、8倍和10倍胸径的两侧(东西方向)与四侧(东南西北方向)进行根剪,分别以6-2、8-2、10-2、6-4、8-4、10-4表示,共7个处理。于2016年10月采集根际土样并测定了杨树根际土壤根系分泌物含量、理化性状和微生物功能多样性及材积生长量。【结果】与对照(未根剪)相比,8倍胸径两侧根剪处理(8-2),杨树根系分泌物中有机酸总量和氨基酸总量的增幅最大,分别显著增加44.6%和26.0%(P<0.05);其次为10倍胸径四侧(10-4)、8倍胸径四侧处理(8-4),均显著高于对照;而6倍胸径两侧(6-2)或四侧处理(6-4)显著低于对照。8倍胸径两侧处理(8-2)根际土壤有效磷、总有机碳和活性有机碳含量显著高于其他处理,分别较对照提高15.8%、39.6%和35.8%;其碱解氮、速效钾含量和p H值显著低于其他处理,较对照分别下降11.6%、26.0%和0.67个单位。8-2处理还使土壤微生物的AWCD值、Shannon指数和Mc Intosh指数显著高于其他处理,分别较对照提高46.6%、27.8%和44.1%;其次为10-4或8-4处理,显著高于对照,而6-2或6-4处理则显著低于对照;8-2处理的Simpson指数最低,与其他处理差异达显著水平,其中较对照下降22.8%。此外,8-2处理使杨树的材积平均生长率达到58.2%,较CK、6-2、6-4、8-4、10-2、10-4处理显著提高43.6%、64.4%、84.8%、25.8%、42.2%和17.1%。【结论】距离树干8倍胸径两侧的根剪措施能显著促进欧美I-107杨根系分泌物的分泌和提高微生物功能多样性,并改善土壤理化性状,有利于林木的生长,其作用效果显著优于6倍胸径两侧或四侧、8倍胸径四侧、10倍胸径两侧或四侧的根剪措施。【Objectives】The aims of this study were to explore the effects of root pruning on microbial characteristics in the rhizosphere soil and growth of Populus euramericana cv. ‘Neva＇, and provide a theoretical foundation for high-yield cultivation of Populus euramericana cv. ‘Neva＇.【Methods】A field experiment was conducted, in which the root systems of five-year-old poplar were manually pruned with a sharp spade at six, eight and ten times of DBH（diameter at breast height） distance along both sides（east-west direction） or four sides（south-east-north and west direction） prior to buds break, named 6-2, 8-2, 10-2, 6-4, 8-4 and 10-4 treatment,respectively. The experiment began in April of 2014 and the rhizosphere soil was collected in October of 2016 to evaluate effects of different root pruning treatments on root exudates contents, physicochemical properties, and microbial functional diversity in rhizosphere soil and volume growth of poplar.【Results】In comparison with the CK（un-pruned）, the pruning at eight times on two sides significantly increased the total organic acids and total amino acids contents in the root exudates, with the increased rates of 44.6% and 26.0%, respectively. The pruning at ten times on four sides and eight times on four sides also showed significant increase effect, whereas the pruning at the six times on both two sides and four sides showed adverse effect. In treatment of running at eight times on two sides, the rhizosphere soil available P, organic C and active organic C contents were significantly higher than those in other treatments, and were 15.8%, 39.6% and 35.8% higher than those in the CK; the available N, readily available K contents and p H value were lowest and obviously lower than those in other treatments, and were 11.6%, 26.0% and 0.67 lower than those in the CK, respectively; the values of AWCD and indexes of Shannon and Mc Intosh were significantly higher than those in other treatments, and were 46.6%,27.8% and 44.1% higher than those in the CK

关 键 词：欧美I-107杨 根剪 生物学特征 微生物功能多样性 

分 类 号：S714.3[农业科学—林学] S792.11