Profile Distribution of Available Boron and Secondary Micro Nutrients in Rice-Groundnut Growing Soils of Jajpur District, Odisha, India

An investigation was conducted to examine the distribution of available Boron secondary micro nutrients and the relationships between boron with soil properties and other nutrients in the rice-groundnut growing soils of Jajpur district, Odisha. The clay content increased downward without following any definite trend. Soil pH of surface horizons was acidic and increased downward to neutral range. EC ranged between 0.02 dSm-1 to 0.13 dSm-1. The soil organic carbon ranged from 0.17% to 0.63% with decreasing trend towards sub surface horizon. The exchangeable Ca, Mg and S content varied from 3.68 mg kg-1 to 6.76 mg kg-1, 0.82 cmole (p+) kg‑1 to 6.24 cmole (p+) kg-1 and 0.62 mg kg-1 to 14.19 mg kg-1 respectively. Ca and Mg increased with increasing depth, whereas S showed the reverse trend. The DTPA- Fe, Mn, Cu, Zn and B content of pedon soil ranged from 60.68 mg kg-1 to 312.08 mg kg-1, 6.48 mg kg-1 to 36.76 mg kg-1, 0.62 mg kg-1 to 4.15 mg kg-1, 0.42 mg kg-1 to 1.15 mg kg-1 and 0.05 mg kg-1 to 1.01 mg kg-1 respectively Fe, Mn and Zn increased from surface to sub surface but Cu and B showed the reverse trend. The availability of Boron is positively correlated with organic carbon, Exch. Mg, Fe, and Cu. Negatively correlated with pH, Exch. Ca, S, Mn, and Zn. Pedon soils were deficient with B, S, Zn and rich in Ca, Mg, Fe, Mn and Cu. Fe was in toxic level in table land zone of sukinda. The available B was found to be deficient throughout the district in up and medium land except in subsurface layers of low land. The availability of B is positively correlated with organic carbon, Exch. Mg, Fe and Cu factors but negatively correlated with pH, Exch. Ca, S, Mn, and Zn. In an agricultural district like Jajpur the key element B for rice-groundnut crop sequence should be applied to soil and leaf of rice, groundnut, and other crops grown in the district.