References
- Ali , M M , Saheed , S M , Kubota , D , Masunaga , T and Wakatsuki , T. 1997 . Soil degradation during the period 1967–1995 in Bangladesh, II. Selected chemical characteristics . Soil Sci Plant Nutr , 43 : 879 – 890 .
- Beckett , P HT. 1964 . The ‘immediate’ Q/I relations of labile potassium in the soil . J Soil Sci , 15 : 9 – 23 .
- Beckett , P HT and Nafady , M HM. 1968 . A study on soil series: their correlation with the intensity and capacity properties of soil potassium . J Soil Sci , 19 : 216 – 236 .
- Bertsch , P M and Thomas , G W. 1985 . “ Potassium status of temperate region soils. In ” . In Potassium in agriculture , Edited by: Munson , R D . 131 – 162 . Madison (WI) : ASA, CSSA, and SSSA .
- Bhandari , A L , Ladha , J K , Pathak , H , Dawe , D and Gupta , R K. 2003 . Trends in yield and soil nutrient status in a long-term rice–wheat experiment in Indo-Gangetic Plains of India . Soil Sci Soc Am J , l66 : 162 – 170 .
- Bijay-Singh , Yadvinder-Singh , Imas , P and Jian-Chang , X. 2003 . Potassium nutrition of the rice–wheat cropping system . Adv Agron , 81 : 203 – 259 .
- Chang , S C. 1971 . Chemistry of paddy soils (Ext. Bull. 7) , Taipei (Taiwan) : ASPAC Food and Fertilizer Technology Center .
- Cox , A E , Joern , B C , Brouder , S M and Gao , D. 1999 . Plant-available potassium assessment with a modified sodium tetraphenyl boron method . Soil Sci Soc Am J , 63 : 902 – 911 .
- Dobermann , A , Cassman , K G , Mamaril , C P and Shesby , J E. 1999 . Management of phosphorus, potassium, and sulfur in intensive irrigated lowland rice . Field Crops Res , 56 : 113 – 118 .
- Dobermann , A and Fairhust , T. 2000 . Rice: Nutrient disorders and nutrient management , Singapore : Potash and Phosphate Institute (PPI), Potash and Phosphate Institute of Canada (PPIC), East and Southeast Asia Program .
- Evangelou , V P , Wang , J and Phillips , R E. 1994 . New developments and perspectives on soil potassium quantity intensity relationships . Adv Agron , 52 : 173 – 227 .
- Gami , S K , Ladha , J K , Pathak , H , Shah , M P , Pasquin , E , Pandey , S P , Hobbs , P R , Joshy , D and Mishra , R. 2001 . Long-term changes in yield and soil fertility in a 20-year rice–wheat experiment in Nepal . Biol Fertil Soils , 34 : 73 – 78 .
- Gee , G W and Bauder , J W. 1986 . “ Particle-size analysis. In ” . In Methods of soil analysis, part 1. Physical properties , Edited by: Klute , A . 383 – 412 . Madison (WI) : ASA and SSSA .
- Mengel , K and Busch , R. 1982 . The importance of potassium buffer power on the critical potassium level in soils . Soil Sci , 133 : 27 – 32 .
- Nair KPP . 1996 . The buffering power of plant nutrients and effects on availability . Adv Agron , 57 : 237 – 287 .
- Nair , K PP , Sadanandan , A K , Hamza , S and Abraham , J. 1997 . The importance of potassium buffer power in the growth and yield of cardamom . J Plant Nutr , 20 : 987 – 997 .
- Nelson , D W and Sommers , L E. 1982 . “ Total carbon, organic carbon, and organic matter. In ” . In Methods of soil analysis, part 2. Chemical and microbiological properties , Edited by: Page , A L , Miller , R H and Keeney , D R . 539 – 577 . Madison (WI) : ASA and SSSA .
- Regmi , A P , Ladha , J K , Pasquin , E , Pathak , H , Hobbs , P R , Shrestha , L , Gharti , D B and Duveiller , E. 2002 . The role of potassium in sustaining yields in a long-term rice–wheat experiment in the Indo-Gangetic Plains of Nepal . Biol Fertil Soil , 36 : 240 – 247 .
- Shaista , N and Wani , M A. 2009 . Forms of potassium and potassium adsorption behavior of soils under different cropping sequences . SKUAST J Res , 11 : 278 – 284 .
- Singh , M , Singh , V P and Reddy , D D. 2002 . Potassium balance and release kinetics under continuous rice–wheat cropping system in Vertisol . Field Crops Res , 77 : 81 – 91 .
- Soil Survey Staff . 1996 . Soil survey laboratory methods manual (Soil Survey Investigations Report No. 42, ver. 3.0) , Washington (DC) : USDA .
- Sparks , D L and Huang , P M. 1985 . “ Physical chemistry of soil potassium. In ” . In Potassium in agriculture , Edited by: Munson , RD . 201 – 276 . Madison (WI) : ASA, CSSA, and SSSA .
- Sparks , D L and Liebhardt , W C. 1981 . Effect of long-term lime and potassium applications on quantity–intensity (Q/I) relationships in sandy soils . Soil Sci Soc Am J , 45 : 786 – 790 .
- Srivastava , S , Rupa , T R , Swarup , A and Singh , D. 2002 . Effect of long-term fertilization and manuring on potassium release properties in a Typic Ustochrept . J Plant Nutr Soil Sci , 165 : 352 – 356 .
- Timsina , J and Connor , D J. 2001 . Productivity and management of rice–wheat cropping systems: issues and challenges . Field Crop Res , 69 : 93 – 132 .
- Vitosh , M L , Johnson , J W and Mengle , D B. 1995 . Tri-state fertilizer recommendation for corn, soybean, wheat, and alfalfa (Ext. Bull. E2567) , East Lansing (MI) : Michigan State University .
- Wang , J J , Harrell , D L and Bell , P F. 2004 . Potassium buffering characteristics of three soils low in exchangeable potassium . Soil Sci Soc Am J , 68 : 654 – 661 .
- Wani , M A and Rajkumar. 2008 . Distribution of potassium and clay mineral assemblage in some paddy soils of Lesser Himalayas . Agropedology , 18 : 98 – 105 .
- Wani , M A , Wani , J A and Bhat , M A. 2009 . Potassium forms, their interrelationship and relationship with soil properties in rice soils of Lesser Himalayas . SKUAST J Res , 11 : 1 – 7 .
- Yadvinder-Singh , Bijay-Singh and Timsina , J. 2005 . Crop residue management for nutrient cycling and improving soil productivity in rice-based cropping systems in the tropics . Adv Agron , 85 : 269 – 407 .