Vol. 11, Issue 8 (2022)

Author(s):
Devendra Kumar Inwati, BK Dixit, BS Dwivedi, Risikesh Thakur, Abhishek Sharma and Vivek Singh

Abstract:
The present study was conducted during 2019-20 at the Research Farm of the Department of Soil Science, Jawaharlal Nehru Krishi Vishwa Vidyalaya, Jabalpur, Madhya Pradesh, India to study the various potassium fractions from 48-year-old long term fertilizer experiment on a Vertisol under soybean–wheat cropping system. The experiment consists of ten treatments i.e. T₁ 50% NPK, T₂ 100% NPK, T₃ 150% NPK, T₄ 100% NPK + HW, T₅ 100% NPK + Zn, T₆ 100% NP, T₇ 100% N, T₈ 100% NPK+FYM, T₉ 100% NPK–S and T₁₀ control with four replications in a randomized block design. The findings showed that applications of inorganic fertilizers with or without organic manure significantly increased the organic carbon, available potassium and different K fractions i.e. water soluble-K, exchangeable-K, non-exchangeable-K, lattice-K and total-K as compared to control plot and without K input (100% NP & 100% N alone) treatments. Among the various K fractions lattice K was dominant K fraction. The highest values of these fractions were found in 100% NPK + 5 t FYM ha^-1 treatment. While the lowest values were observed in control plot. The relative contents of these fractions were in order: lattice-K > non-exchangeable K > exchangeable K > water soluble K.