钼对苹果砧木平邑甜茶幼苗硝态氮吸收、转化及分配的影响  

Effect of molybdenum on absorption,transformation and distribution of nitrate-nitrogen of apple rootstock Malus hupehensis Rehd. seedlings

作　　者：刘利[1] 欧志锋 姜远茂[1] 魏绍冲[1] 

机构地区：[1]作物生物学国家重点实验室山东果蔬优质高效生产协同创新中心山东农业大学园艺科学与工程学院,山东泰安271018

出　　处：《植物营养与肥料学报》2015年第3期727-733,共7页Journal of Plant Nutrition and Fertilizers

基　　金：现代农业产业技术体系建设专项资金(CARS-28);公益性行业(农业)科研专项资金(201103003)资助

摘　　要：【目的】氮肥利用率低是制约果树产业可持续发展的重要因素之一。过量施用氮肥以及不当的农业措施造成当前多数苹果果园发生不同程度的土壤酸化,而钼在酸性土壤中有效含量的降低会影响氮素吸收利用效率。本试验旨在探索能提高氮肥吸收利用效率的适宜钼用量,了解钼对苹果砧木平邑甜茶(Malus hupehensis Rehd.)幼苗硝态氮吸收、转化和分配利用特性的影响,为苹果生产中钼肥与氮肥的合理施用提供科学数据。【方法】以平邑甜茶幼苗为试验材料,采用全硝态氮霍格兰营养液进行培养。试验设置5个供钼水平:营养液不含钼(CK);营养液含0.25μmol/L钼酸(M1);营养液含0.5μmol/L钼酸(M2);营养液含1.5μmol/L钼酸(M3);叶片喷0.04%钼酸,营养液不含钼(M4)。运用15N同位素示踪技术,研究不同供钼水平对幼苗15N吸收量、全氮量、分配率和利用率的影响,同时测定钼对不同时期幼苗叶片和根系硝酸还原酶活性的影响。【结果】供钼处理幼苗的根系活力不同程度地高于不施钼处理(对照),其中营养液含0.5μmol/L钼酸的处理(M2)效果最佳。培养8 d内M2处理的平邑甜茶幼苗的根系硝酸还原酶活性一直高于其他处理,且与对照差异显著;培养4 d时各种处理的叶片硝酸还原酶活性上升至最高值,随后下降,8 d后又出现上升和下降的趋势,但上升幅度明显小于培养4 d。M1、M2、M3和M4处理的植株总干重分别比CK提高3.88%、21.12%、12.38%和19.90%。与对照相比,0.5μmol/L钼酸处理幼苗的15N吸收量增加的比例最大,全氮量表现出相同的趋势。供钼处理的氮肥利用率均明显高于对照,其中以0.5μmol/L钼酸处理的效果最显著,利用率为13.97%,比对照高48.92%。施钼处理对幼苗的15N分配率有一定的影响,0.5μmol/L钼酸处理(M2)和叶片喷施0.04%钼酸处理(M4)的茎和叶片的15N分配率明显高于对照,对照根系中15N分配率最高。0.5μmol/【Objectives 】 The low nitrogen fertilizer use efficiency restricts sustainable development of fruit industry. Excessive application of nitrogen fertilizer and improper agricultural measures lead to soil acidification with different degrees in current apple orchards in China,and soil acidification can cause low content of soil available molybdenum,which decreases nitrogen fertilizer use efficiency. The aim of the study was to explore appropriate molybdenum( Mo) level to enhance nitrogen fertilizer use efficiency of Malus hupehensis Rehd.seedlings,and provide scientific data for utilization of nitrogen and molybdenum fertilizer in apple industry.【Methods】Malus hupehensis Rehd. seedlings were used as experiment materials and the Hoagland solution with nitrate N was used as only N source in the study. The experiment included five different Mo levels: control( CK,no Mo in solution),M1( 0. 25 μmol / L molybdic acid in solution),M2( 0. 5 μmol / L molybdic acid in solution),M3( 1. 5 μmol/L molybdic acid in solution) and M4( spraying 0. 04% molybdic acid,no Mo in solution). Effects of Mo on absorption,transformation,and distribution of nitrate-nitrogen in the seedlings were detected using the15N-labeled tracer method,meanwhile effects of Mo on nitrate reductase( NR) activity of leaves and roots in Malus hupehensis Rehd. seedlings were analysed in the study. 【Results】Mo can enhance root activity of the seedlings with different degrees and the treatment with 0. 5 μmol / L Mo in solution has the highest effect in the study. The NR activity in roots of the treatment with 0. 5 μmol / L Mo is higher than that of the other treatments on the 8 d,and there is significant difference between the treatment with 0. 5 μmol / L Mo and the control. The leaf NR activities in all the treatments reach the maxima on the 4 d and then decrease. The dry weight amounts of M1,M2,M3 and M4 treatments are higher than that of the control and are increased by 3. 88%,21. 12%,12. 38% and 19. 90%,respectively. The15 N absorption of M2

关 键 词：钼 平邑甜茶 15N 吸收 分配 利用 

分 类 号：S661.1[农业科学—果树学]