Impingement of NPK and Rhizobium on Physico-chemical Properties of Soil under Cluster Bean (Cyamopsis tetragonoloba L.)

The study pertaining to the present topic under field investigation entitled “effect of different levels of NPK and Rhizobium on Physico-chemical properties of soil, growth and yield attributes of cluster bean” beginning from kharif seasons of the years 2023 at Research Farm, Department of Soil Science and Agricultural Chemistry. The excavated soil sample from experimental site before conducting research operation, mentioned that, the land topography range was nearly levelled with 1-3% slope, soil is of sandy loam texture with neutral to alkaline in reaction (7.140), electrical conductivity was non-saline (0.346 dS m-1) in nature, low organic carbon content (0.38%), low to medium available N (261.39 kg ha-1), available P (14.60 kg ha- 1) and available K (193.99 kg ha-1). Among nine treatments, during field experimentation, the conjunctive use of NPK and different Rhizobium levels, together come with best results significantly. However, the physical and chemical soil parameters, cumulative mean value for Bulk density (1.42 Mg m-3 and 1.45 Mg m-3),Particle density (2.64 Mg m-3 and 2.66 Mg m-3) and Soil pH (7.140 and 7.370) was found optimum in T1 (Absolute control) at 0-15 cm depth and 15-30 cm depth, respectively. Percentage porespace (45.17% and 43.17%), Water holding capacity (42.32% and 39.70%), Electrical conductivity (0.323 dS m-1 and 0.300 dS m-1), Percentage organic carbon (0.49% and 0.46%), Available N (284.41 kg ha-1 and 281.48 kg ha- 1 ), Available P (22.54 kg ha-1 and 21.29 kg ha-1 ), Available K (210.52 kg ha-1 and 203.98 kg ha-1 ) were found optimum in T9 consisting of (@ 100% NPK + @ 100% Rhizobium) in comparison to other NPK and Rhizobium levels application.