Five decadal nutrient management effects on productivity, sustainability and soil properties in a maize–wheat system on Alfisols of North-western Himalayas

The excessive use of fertilisers with intensive farming practices has threatened the sustainability of agricultural systems, particularly in acid soils. It is crucial to understand the long-term impacts of fertilisers and amendments on yield sustainability and soil properties. This study aimed to determine the long-term effects of chemical fertilisers and amendments on yield sustainability, nutrient uptake, soil organic carbon (SOC) sequestration and di-ethylene tri-amine penta acetic acid (DTPA)-extractable micronutrients content. The study is a part of a long-term experiment initiated in 1972 on Alfisols of North-western Himalayas. Ten treatments comprising chemical fertilisers, FYM and lime, and one unfertilised control, were replicated thrice in a randomised block design. The results revealed that the application of 100% NPK + FYM improved the grain yield, straw yield and sustainable yield index (SYI) of wheat by 67.5, 65.0, and 68.0%, respectively, over NPK alone. The nutrient uptake by wheat and SOC sequestration was significantly higher in 100% NPK + FYM and 100% NPK + lime treatments than the rest of the treatments. The application of 100% NPK + FYM increased the DTPA-extractable iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) by 17.8, 74.7, 98.4 and 31.0%, respectively, over NPK alone and found to be statistically at par with the treatment 100% NPK + lime.