1. Available nitrogen in soils and its determination by the ‘Nmin-method’ and by electroultrafiltration (EUF)

   • K. Mengel

   OriginalPaper Pages: 251 - 262

2. Recovery of¹⁵N-labelled urea: Influence of zero tillage, and time and method of application

   • S. S. Malhi
   • M. Nyborg

   OriginalPaper Pages: 263 - 269

3. Comparison of five soil testing methods to establish phosphorus sufficiency levels in soil fertilized with water-soluble and sparingly soluble-P sources

   • A. Bationo
   • W. E. Baethgen
   • A. U. Mokwunye

   OriginalPaper Pages: 271 - 279

4. Partially acidulated reactive phosphate rock (PAPR) fertilizer and its reactions in soil

   • D. C. Golden
   • R. E. White
   • R. B. Stewart

   OriginalPaper Pages: 281 - 293

5. Partially acidulated reactive phosphate rock (PAPR) fertilizer and its reactions in soil

   • D. C. Golden
   • R. B. Stewart
   • R. E. White

   OriginalPaper Pages: 295 - 304

6. Residual effects of phosphate fertilizers in relation to phosphate sorptivities of 27 soils

   • I. C. R. Holford
   • G. J. Crocker

   OriginalPaper Pages: 305 - 314

7. Influence of modified forms of urea and nitrogen levels on weed growth and grain yield of lowland rice

   • R. Venkitaswamy
   • S. Subramanian
   • V. Veerabadran

   OriginalPaper Pages: 315 - 321

8. Urea briquette applicator for transplanted rice

   • N. K. Savant
   • P. S. Ongkingco
   • P. J. Stangel

   OriginalPaper Pages: 323 - 331

9. Characterization of humified substances in organic fertilizers by means of analytical electrofocusing (EF): A first approach

   • M. Govi
   • C. Ciavatta
   • P. Sequi

   OriginalPaper Pages: 333 - 339

10. Humic fertilizers by oxiammoniation of hydrolyzed olive pits residues

    • F. A. Riera
    • R. Alvarez
    • J. Coca

    OriginalPaper Pages: 341 - 348