Plant-available potassium assessment with a modified sodium tetraphenylboron method

被引:126
作者
Cox, AE
Joern, BC [1 ]
Brouder, SM
Gao, D
机构
[1] Purdue Univ, Dept Agron, W Lafayette, IN 47907 USA
[2] CH2M Hill Inc, Redding, CA 96001 USA
关键词
D O I
10.2136/sssaj1999.634902x
中图分类号
S15 [土壤学];
学科分类号
0903 ; 090301 ;
摘要
The conventional 1 M NH4OAc-exchangeable potassium (K+) soil test is inadequate in soils where nonexchangeable K+ contributes significantly to crop nutrition. Studies were conducted (i) to compare the abilities of the I M NH4OAc method with a modified NaBPh4 method to estimate critical soil K+ levels, (ii) to estimate the contribution of nonexchangeable K+ to plant-available Iii, (iii) to compare the abilities of the 1 M NH4OAc method and the modified NaBPh4 method to estimate plant dry matter yield and plant-available K+, and (iv) to compare the abilities of both methods to measure soil K+ balance. Winter wheat (Triticum aestivum L. 'Abe') was grown in eleven Midwestern soils in a greenhouse using consecutive 28-d defoliation and regrowth cycles. Soils also were incubated for 6 mo with five K+ rates (0-809 mg K+ kg(-1)). Ammonium acetate- and NaBPh4-extractable K+ (5-min extraction period) were determined in soil samples taken after every three defoliation cycles and after incubation, Critical soil K+ levels could not be determined by either method alone but could be predicted by including cation-exchange capacity (CEC) and illitic K+ content in regression models. Nonexchangeable K+ represented a significant portion of plant-available K+. Plant-available K+ and dry matter (DM) yield were well related to NH4OAc-extractable KI only in soils with low nonexchangeable K+ contribution (r(2) = 0.889 and 0.915, respectively), but they were well related to NaBPh4-extractable KI in all soils (r(2) = 0.984 and 0.874, respectively). Slopes for NH4OAc-extractable K+ vs, soil K+ balance varied widely among soils (0.16-0.68) depending on NH4OAc-extractable K+, illitic K+. and clay content, but for NaBPh4-extractable K+ slopes were near unity, These studies suggest that the modified NaBPh4 method may be a superior Kt soil test compared to the NH4OAc method. Illite content and CEC data may help in developing better soil Kt management guidelines.
引用
收藏
页码:902 / 911
页数:10
相关论文
共 44 条
[1]   IMPORTANCE OF ILLITE AS A SOURCE OF POTASSIUM IN NEBRASKA SOILS [J].
ABED, FMA ;
DREW, JV .
SOIL SCIENCE SOCIETY OF AMERICA PROCEEDINGS, 1966, 30 (02) :242-&
[2]  
Allen S.E., 1976, GREENHOUSE TECHNIQUE
[3]   MOBILIZATION OF NON-EXCHANGEABLE-K BY RYEGRASS IN 5 MOROCCAN SOILS WITH AND WITHOUT MICA [J].
BADRAOUI, M ;
BLOOM, PR ;
DELMAKI, A .
PLANT AND SOIL, 1992, 140 (01) :55-63
[4]  
BARBER T. E., 1962, CANADIAN JOUR SOIL SCI, V42, P266
[7]   POTASSIUM-SUPPLYING POWER OF SEVERAL INDIANA SOILS [J].
BRELAND, HL ;
BERTRAMSON, BR ;
BORLAND, JW .
SOIL SCIENCE, 1950, 70 (03) :237-247
[8]   COMPARISON OF SOIL TEST METHODS FOR PREDICTING COTTON RESPONSE TO SOIL AND FERTILIZER POTASSIUM ON POTASSIUM FIXING SOILS [J].
CASSMAN, KG ;
BRYANT, DC ;
ROBERTS, BA .
COMMUNICATIONS IN SOIL SCIENCE AND PLANT ANALYSIS, 1990, 21 (13-16) :1727-1743
[9]   VERMICULITE DETERMINATION ON WHOLE SOILS BY CATION-EXCHANGE CAPACITY METHODS [J].
COFFMAN, CB ;
FANNING, DS .
CLAYS AND CLAY MINERALS, 1974, 22 (03) :271-283
[10]   Release kinetics of nonexchangeable potassium in soils using sodium tetraphenylboron [J].
Cox, AE ;
Joern, BC .
SOIL SCIENCE, 1997, 162 (08) :588-598