01490naa a2200181 a 450000100080000000500110000800800410001910000190006024501240007926000090020352009740021265000130118665000110119965000090121065000220121965300100124177300570125111978862020-06-25       1991    bl uuuu     u00u1 u    #d1 aFAGERIA, N. K.  aResponse of cowpea to phosphorus on an oxisol with special reference to dry matter production and mineral ion contents.  c1991  aThe objective of this investigation was to evaluate the effects of P fertilization on growth, yield and nutrient uptake pattems in cowpea. Phosphorus application significantly increased growth, yield and yield components. The critical soil-applied P leveI was 160 mg kg-1 of soil for seed yield and 142-150 mg P kg-1 of soil for yield components. The criticallevel of soil P extracted for seed yield was 40 mg kg-1 of soil and the plant tissue critical level was 0.13% at harvest. Analyses of nutrient distributions in different plant parts showed that cowpea roots retained maximum Fe and minimum K and Ca. Tops retained maximum Ca, almost 50% of P, K and Mg and 65% of Mn; large amounts of P, K, Zn and Cu were translocated to seeds. Pod husks contained a high leveI of Mg and Cu. Phosphorus fertilization decreased the concentrations of K, Zn and Cu in plant tops. Magnesium concentration was increased with P fertilization; Ca and Fe concentrations were unaffected.  aFósforo  aOxisol  aSolo  aVigna Unguiculata  aCaupi  tTropical Agriculturegv. 68, n. 4, p. 384-388, 1991.