Effect of Different Levels of NPK, Biochar and Azotobacter on Physico-chemical Properties of Soil on Cowpea (Vigna unguiculata)

In light of this, the following goals are present in the experiment "Effect of Different Levels of NPK and Biochar, Azotobacter on Physico-chemical Properties of Soil and Yield Attributes of Cowpea to calculate the impact of various NPK, Biochar, and Azotobacter dosages on the physical-chemical characteristics of soil. An excavated soil sample from the experimental site revealed that the land topography ranged from nearly level to sloped by 1% to 6%, with soil area falling into the Inceptisol order. The soil texture was sandy loam, with sand percentages of 62.65%, silt percentages of 21.09, and clay percentages of 16.26. The pH of soil was 6.89, and its electrical conductivity (EC) was non-saline (0.42 ds m-1). Organic carbon content was low to medium, available nitrogen was low to medium (280.78 kg ha-1), available phosphorus was 17.34 kg ha-1, and available potassium was 168.16 kg ha-1. Two factors with three levels of @NPK 0, 50, and 100% ha-1, three levels of @Biochar 0, 50, and 100% ha-1, and a randomized block design were used in the statistical analysis. During field testing, nine different treatments were used; the best outcomes were significant. The results indicate that the physical and chemical parameters of the soil, including the cumulative mean values for bulk density (1.39 and 1.41 mg m-3), particle density (2.46 and 2.47 mg m-3), and soil pH (6.89 and 6.91), attained their maximum in T1 (Absolute control) at depths of 0-15 cm and 15-30 cm, respectively. Additionally, the percentage pore space was found to be 48.22% and 47.39%, and the water holding capacity was found to be 44.14% and 45.34%), electrical conductivity (EC) was measured at 0.49 ds m-1 and 0.52 ds m-1, the percentage of organic carbon was determined to be 0.40%), and the available nitrogen was found to be (299.78 kg ha-1 and 295.76 kg ha-1, available phosphorus was (23.78 kg ha-1 and 21.98 kg ha-1), and the available potassium was (179.25 kg ha-1 and 176.56 kg ha-1).