脐橙幼树夏施^(15)N–尿素的利用与土壤残留初探  

Preliminary Study on Utilization of^(15)N-urea Applied to Young Navel Orange Trees in Summer and Its Residual in Soil

作　　者：胡亚伟 马金龙 钟八莲 姚锋先[1,2] 刘桂东 HU Yawei;MA Jinlong;ZHONG Balian;YAO Fengxian;LIU Guidong(College of Life Sciences,Gannan Normal University,Ganzhou,Jiangxi 341000,China;National Navel Orange Engineering Research Center,Ganzhou,Jiangxi 341000,China)

机构地区：[1]赣南师范大学生命科学学院,江西赣州341000 [2]国家脐橙工程技术研究中心,江西赣州341000

出　　处：《园艺学报》2025年第3期705-713,共9页Acta Horticulturae Sinica

基　　金：国家自然科学基金项目(32160746);江西省自然科学基金重点项目(20212ACB205008)。

摘　　要：通过测定脐橙幼树氮素的吸收利用及其在土壤中的残留与损失情况,为进一步优化幼树期脐橙生产体系氮素管理提供依据。以2年树龄的‘纽荷尔’脐橙/枳和‘赣南早’脐橙(纽荷尔脐橙的芽变早熟品种)/枳为试材,采用^(15)N同位素示踪技术,于夏季分两次施入同位素标记氮肥,在当年秋梢老熟后采集植物和土壤样品,测定植物各器官和不同土层土壤^(15)N丰度并计算氮素利用率及其残留和损失情况。结果显示,纽荷尔和赣南早脐橙的生物量存在明显差异,但各部位干物质量在整株中的占比一致,当年生叶片和枝条在整株干物质中的占比达40%以上,为脐橙幼树树体生长中心,^(15)N均主要分配到其中;纽荷尔二年生叶片和粗根中的^(15)N分配率显著高于赣南早,而在枝条和主干等非功能器官中显著低于赣南早。纽荷尔对^(15)N标记尿素的当年利用率、土壤残留率和损失率分别为6.45%、75.72%和17.83%,赣南早则为3.36%、54.25%和42.39%。上述结果表明,脐橙幼树对夏施氮肥的当年利用率较低,两个品种幼龄脐橙园氮素去向存在明显差异,可能与不同品种生物量(包括根系分布)存在显著差异有关。By measuring the absorption and utilization of nitrogen in navel orange plants,as well as their residual and loss in the soil,this provides a basis for further optimizing nitrogen management in the navel orange production system during the no-bearing stage.The experiment used 2-year-old Newhall and Gannanzao navel orange grafted on trifoliate orange as materials.^(15)N isotope tracing technology was used,and labeled nitrogen fertilizer was applied twice in summer.After the autumn shoots matured,plant and soil samples were collected to measure the^(15)N abundance of various plant organs and soil layers,and then calculate nitrogen utilization,residue,and loss.The results showed that there is a significant difference in biomass between Newhall and Gannanzao navel oranges,but the proportion of dry matter of each part in the whole plant was consistent.The proportion of dry matter of 1-year-old leaves and branches in the whole plant was over 40%,which was the growth centers of young navel orange trees,and^(15)N was mainly distributed to these organs.The allocation rate of^(15)N in Newhall is significantly higher than that in Gannanzao in 2-year-old leaves and coarse roots,and significantly lower than that in branches and trunk.The annual utilization rate,soil residual and loss percentage of^(15)N labeled urea for young Newhall navel orange trees were 6.45%,75.72%,and 17.83%,respectively,while for Gannanzao,they were 3.36%,54.25%,and 42.39%,respectively.The above results indicate that the utilization efficiency of nitrogen fertilizer applied in summer for young navel orange trees is relatively low,and there are significant differences in the fate of nitrogen in different varieties of navel orange orchards,which may be related to significant differences in biomass(including root architechture)between the two varieties.

关 键 词：柑橘 氮素 同位素 利用 土壤残留 

分 类 号：S666.4[农业科学—果树学]