摘要
灌溉和磷添加是紫花苜蓿(Medicago sativa)栽培草地稳产的关键因素。本研究采用盆栽试验,分析了不同磷添加量(0、64、127和191 mg·kg^(-1))和灌溉量(40%~45%、60%~65%和80%~85%土壤饱和含水量)互作下紫花苜蓿的株高、分枝数、叶片数、茎粗、单株产量、单位面积产量和磷肥农学效率,以期证实灌溉和磷添加互作时是否存在最佳理论组合。结果表明:随灌溉量增大,紫花苜蓿的株高、分枝数和叶片数均呈增加趋势,茎粗及其第1茬单株和单位面积产量先增加后降低,第2茬单株和单位面积产量呈先增大后相对稳定趋势;而其磷肥农学效率则随灌溉量增加呈先相对稳定后降低的变化趋势。随磷添加量增加,紫花苜蓿的株高、叶片数、单株产量和单位面积产量呈增加趋势,分枝数和茎粗先增加后降低;而其磷肥农学效率呈先增大后相对稳定趋势。灌溉与磷添加互作显著影响紫花苜蓿第1茬和第2茬的株高、分枝数、茎粗、单株产量、单位面积产量和磷肥农学效率(P <0.05),且单位面积产量与灌溉量和磷添加量的关系表现为开口向下抛物面模式,磷肥农学效率与灌溉量和磷添加量的关系亦表现为开口向下抛物面模式。当灌溉量为土壤饱和含水量的60%、磷添加量为127 mg·kg^(-1)时,紫花苜蓿单位面积产量最大,磷肥农学效率最高;说明灌溉量和磷添加量互作时理论上存在最佳组合。
Irrigation and phosphorous application rates are two key factors affecting the yield of alfalfa(Medicago sativa)pastures.In this study,a greenhouse pot experiment was conducted to identify an optimal combination between irrigation and phosphorous application rate.The effects of different combinations of irrigation volume and phosphorous application rates on the plant height,branch number,leaf number,stem diameter,dry yield per unit area(YPUA),dry yield per plant(YPP)and agronomic efficiency of applied phosphorous(AEP)were investigated.Specifically,the irrigation volumes tested consisted of 40%~45%,60%~65%and 80%~85%of saturated soil moisture and phosphorous amounts of 0,64,127 and 191 mg·kg^(-1) were applied.We noticed that for the first alfalfa crop harvest,the plant height,branch and leaf numbers increased with an increase in irrigation volume,while the stem diameter,YPUA and YPP first increased and then decreased.However,the latter parameters first increased and then remained relatively stable for the second harvest.Further,the AEP first remained relatively stable and then decreased.Furthermore,plant height,leaf number,YPUA and YPP increased with an increase in phosphorous application rate.The branch number and stem diameter first increased and then decreased,while the AEP first increased and then remained relatively stable.The interaction between irrigation volume and phosphorous application rate displayed significant effects on the plant height,branch number,stem diameter,YPUA,YPP and AEP(P<0.05).The relationships between YPUA and AEP and irrigation volume showed the downward response in 3D graph.Specifically,irrigation volume leading to 60%saturated soil moisture content,and phosphorous addition of 127 mg·kg^(-1) led to the largest alfalfa YPUA and the highest AEP.These data demonstrated that there exists an optimally theoretical combination between proper irrigation volume and phosphorous application rate under which alfalfa crop displays maximum yield.
作者
冯甘霖
蒋朝
刘彩凤
庞晓攀
刘慧霞
FENG Ganlin;JIANG Zhao;LIU Caifeng;PANG Xiaopan;LIU Huixia(College of Pastoral Agriculture Science and Technology,Lanzhou University,Lanzhou 730020,Gansu,China;College of Life Science and Engineering,Northwest University for Nationalities,Lanzhou 730030,Gansu,China)
出处
《草业科学》
CAS
CSCD
北大核心
2023年第2期448-459,共12页
Pratacultural Science
基金
国家自然科学基金(3216140282)
青海省基础研究计划(2022-ZJ-904)。
关键词
灌溉量
磷添加量
互作
紫花苜蓿
产量
磷肥农学效率
最佳理论组合
irrigation volume
phosphorous application rate
interaction
Medicago sativa
yield
agronomic efficiency(AEP)
optimal combination
