摘要
以高效型苜蓿(‘龙牧806’‘肇东苜蓿’)和低效型苜蓿(‘公农1号’‘陇东苜蓿’)为试验材料,采用营养液砂培法,在4个供氮量下(2.1,21,210和420 mg·L^(-1)),研究紫花苜蓿苗期氮素吸收、分配的氮效率型差异及其与根系形态之间的关系。结果表明高效型苜蓿品种的株高、地上生物量、根重、总根长和根体积均显著高于低效型品种(P<0.05);供氮量较低时(2.1和21 mg·L^(-1)),高效型向根系分配了较大比例的氮素,而低效型则向地上部分配了较大比例的氮素,根系形态参数与总氮量呈显著正相关(P<0.05),且根重对氮素吸收的直接作用较大,直接通径系数是1.230和1.102。因此,在氮胁迫下,根系形态对氮吸收效率起重要作用,尤其是根系形态中的根重对其影响较大。
High nitrogen(N)efficient varieties(‘Longmu 806’‘Zhaodong’)and low N efficiency varieties(‘Gongnong No.1’‘Longdong’)were used to study the genotypic variations in total N uptake and N partition with different nitrogen efficiency and its relation to root morphology at four N levels(2.1,21,210 and 420 mg·L^(-1)).Plant height,aboveground biomass,root dry weight,total root length,and root volume of high N efficient varieties were greater than that of low N efficiency varieties(P<0.05).The higher N accumulation in root in high N efficient varieties at low N supply(2.1 and 21 mg·L^(-1)).The higher N accumulation in aboveground in low N efficient varieties at low N supply.There was a significant positive correlation(P<0.05)between root morphological parameters and total nitrogen,and nitrogen uptake was primarily controlled by root dry weight at low N supply,direct path coefficients were 1.230 and 1.102.When N is a limiting factor for plant growth,root morphology became more important in N uptake,and root dry weight was more important.
作者
郝凤
于铁峰
刘晓静
高凯
HAO Feng;YU Tie-feng;LIU Xiao-jing;Gao Kai(College of Agronomy, Inner Mongolia University for Nationalities, Tongliao, Inner Mongolia 028042, China;Pratacultural College, Gansu Agricultural University, Lanzhou,Gansu Province 730070, China)
出处
《草地学报》
CAS
CSCD
北大核心
2021年第11期2428-2434,共7页
Acta Agrestia Sinica
基金
内蒙古自治区自然科学基金项目(2019LH03011)
内蒙古民族大学博士科研启动基金项目(BS520)
内蒙古民族大学教育教学研究课题(YB2021024)
内蒙古民族大学博士科研启动基金项目(BS521)资助。
关键词
苜蓿
氮效率
根系
氮素吸收
Alfalfa
Nitrogen efficiency
Root
Nitrogen uptake
