1. Humic acids stimulate growth and activity of in vitro tested axenic cultures of soil autotrophic nitrifying bacteria

   • G. Vallini
   • A. Pera
   • M. M. Valdrighi

   ORIGINAL PAPER Pages: 243 - 248

2. Structure of “unknown” soil nitrogen investigated by analytical pyrolysis

   • H.-R. Schulten
   • C. Sorge-Lewin
   • M. Schnitzer

   ORIGINAL PAPER Pages: 249 - 254

3. Influence of pruning frequency of Albizia lebbeck, Gliricidia sepium and Leucaena leucocephala on nodulation and potential nitrogen fixation

   • B. D. Kadiata
   • K. Mulongoy
   • N. O. Isirimah

   ORIGINAL PAPER Pages: 255 - 260

4. Methane-oxidizing activities and methanotrophic populations associated with wetland rice plants

   • I. Watanabe
   • T. Hashimoto
   • A. Shimoyama

   ORIGINAL PAPER Pages: 261 - 265

5. Effects of green manure and coral lime on corn growth and chemical properties of an acid Oxisol in Western Samoa

   • D. J. Hunter
   • L. G. G. Yapa
   • N. V. Hue

   ORIGINAL PAPER Pages: 266 - 273

6. Evaluation of the intrinsic competitiveness and saprophytic competence of Rhizobium tropici IIB strains

   • K. M. Vlassak
   • F. Mercante
   • J. Vanderleyden

   ORIGINAL PAPER Pages: 274 - 282

7. Comparative efficieny of Rhizobium/Bradyrhizobium spp. strains in nodulating Cajanus cajan in relation to characteristic metabolic enzyme activities

   • R. C. Anand
   • R. C. Dogra

   ORIGINAL PAPER Pages: 283 - 287

8. Microcosm experiments on the development of different plant parasitic nematode fauna in two soils from the Soudanese-Sahelian zone of West Africa

   • C. Villenave
   • P. Cadet
   • N. N‘Diaye

   ORIGINAL PAPER Pages: 288 - 293

9. Biological oxidation of nitric oxide in a humisol

   • P. F. Dunfield
   • Roger Knowles

   ORGINIAL PAPER Pages: 294 - 300

10. Interaction between Alternaria alternata or Fusarium equiseti and Glomus mosseae and its effects on plant growth

    • C. B. McAllister
    • J. M. Garcia-Garrido
    • J. A. Ocampo

    ORIGINAL PAPER Pages: 301 - 305

11. Organic matter, microbial biomass and enzyme activity of soils under different crop rotations in the tropics

    • K. Chander
    • S. Goyal
    • K. K. Kapoor

    ORIGINAL PAPER Pages: 306 - 310

12. Effect of rotation, nitrogen fertilization and management of crop residues on some chemical, microbiological and biochemical properties of soil

    • P. Perucci
    • U. Bonciarelli
    • A. A. Bianchi

    ORIGINAL PAPER Pages: 311 - 316

13. Dual inoculation with strains of Bradyrhizobium japonicum and Azospirillum brasilense to improve growth and biological nitrogen fixation of soybean (Glycine max L.)

    • Y. G. M. Galal

    ORIGINAL PAPER Pages: 317 - 322

14. Denitrification with and without maize plants (Zea mays L.) under irrigated field conditions

    • T. Mahmood
    • R. Ali
    • S. R. A. Shamsi

    ORIGINAL PAPER Pages: 323 - 328

15. Effect of phosphate rock, lime and cellulose on soil microbial biomass in acidic forest soil and its significance in carbon cycling

    • Z. L. He
    • V. C. Baligar
    • K. D. Ritchey

    ORIGINAL PAPER Pages: 329 - 334

16. Interactions of clay minerals with Arthrobacter crystallopoietes: starvation, survival and 2-hydroxypyridine catabolism

    • S. Hwang
    • R. L. Tate III.

    ORIGINAL PAPER Pages: 335 - 340

17. Nitrous oxide and methane transport through rice plants

    • K. W. Yu
    • Z. P. Wang
    • G. X. Chen

    SHORT COMMUNICATION Pages: 341 - 343

18. Influence of inoculation with arbuscular mycorrhizal fungi on stable isotopes of nitrogen in Phaseolus vulgaris

    • D. Redecker
    • P. von Berswordt-Wallrabe
    • D. Werner

    SHORT COMMUNICATION Pages: 344 - 346