References
- Burford , J. R. and Sahrawat , K. L. Nitrogen availability in SAT soils: Environment effects on soil processes . Soil fertility and fertilizer management in semi‐arid tropical India. Proceedings of Colloquium held at ICRISAT Center, Patancheru, India . October 10–11 1988 . Edited by: Christianson , C. B. pp. 53 – 60 . Muscle Shoals, Alabama : International Fertilizer Development Center .
- Burford , J. R. , Sahrawat , K. L. and Singh , R. P. Nutrient management in Vertisols in the Indian semi‐arid tropics . Management of Vertisols for improved agricultural production: Proceedings of an IBSRAM inaugural workshop . February 18–22 1985 . pp. 147 – 159 . Patancheru, , India : ICRISAT .
- Dalai , R. C. , Sahrawat , K. L. and Myers , R. J. K. 1984 . Inclusion of nitrate and nitrite in the Kjeldahl determination of soils and plant materials using thiosulphate . Communications in Soil Science and Plant Analysis , 15 : 1453 – 1461 .
- El‐Swaify , S. A. , Pathak , P. , Rego , T. J. and Singh , S. 1985 . Soil management for optimized productivity under rainfed conditions in the semi‐arid tropics . Advances in Soil Science , 1 : 1 – 64 .
- Gehring , A. U. , Guggenberger , G. , Zech , W. and Luster , J. 1997 . Combined magnetic, spectro‐scopic, and analytical‐chemical approach to infer genetic information for a Vertisol . Soil Science Society of America Journal , 61 : 78 – 85 .
- Lee , K. K. , Singh , P. , Wani , S. P. , Rego , T. J. , Trimurtulu , N. and Monteith , J. L. 1996 . “ Effects of fertilizer N and irrigation on root growth, and water uptake with special reference to postrainy season sorghum ” . In Dynamics of roots and nitrogen in cropping systems of the semi‐arid tropics , Edited by: Ito , O. , Johansen , C. , Adu‐Gyamfi , J. J. , Katayama , K. , Kumar Rao , J. V. D. K. and Rego , T. J. 261 – 271 . Ibaraki, , Japan : Japan International Research Center for Agricultural Sciences .
- Nelson , D. W. and Sommers , L.E. 1982 . “ Total carbon, organic carbon, and organic matter ” . In Methods of soil analysis, part 2, , 2nd ed. , Edited by: Page , A. L. 539 – 579 . Madison, Wisconsin : American Society of Agronomy .
- Sahrawat , K. L. 1984 . Effects of temperature and moisture on urease activity in semi‐arid tropical soils . Plant and Soil , 78 : 401 – 408 .
- Sahrawat , K. L. 1995 . Fixed ammonium and carbon‐nitrogen ratios of some semi‐arid tropical Indian soils . Geoderma , 68 : 219 – 224 .
- Sahrawat , K. L. and Ponnamperuma , F. N. 1978 . Measurement of exchangeable NH4+ in tropical rice soils . Soil Science Society of America Journal , 42 : 282 – 283 .
- Tandon , H. L. S. and Kanwar , J. S. 1984 . A review of fertiliser use research on sorghum , Patancheru, , India : ICRISAT . Research bulletin No. 8.
- Waring , S. A. and Bremner , J. M. 1964 . Ammonium production in soil under waterlogged conditions as an index of nitrogen availability . Nature , 201 : 951 – 952 .