The experiment was conducted to study the effect of depth of tillage and manuring on soil physical properties, water conservation, and yield of rice (BRRI dhan49). The experiment was laid out in a split plot design with three tillage treatments in main plot and two manuring treatments in sub-plots. Tillage treatments were: no tillage (To), 0-10 cm deep tillage (T1), and 10-20 cm deep tillage (T2), and manuring treatments were: recommended dose of fertilizers at 90 kg N, 15 kg P, 40 kg K,10 kg S, and 2 kg Zn ha-1 as urea, TSP, MoP, gypsum, and zinc sulphate respectively (F), and 70 % of N plus rest of the recommended dose of fertilizers plus cow dung at 5 t ha-1 (FM). Maximum bulk density of 1.68 g cm-3 and minimum bulk density of 0.75 g cm-3 were recorded under no tillage and deep tillage. In case of manuring, highest bulk density of 1.43 g cm-3 and lowest bulk density of 0.86 g cm-3 were observed under F and FM treatments respectively. Highest value of 47.62% moisture and 14.45% air-filled porosity were measured in T2 treatment. Lowest soil moisture (36.30%) and air-filled porosity (8.50%) were found in To treatment. In manuring, highest soil moisture (45.62%) and air-filled porosity (11.86%) were recorded in FM. Highest grain yield (4.62 t ha-1) was found under T2 treatment and lowest yield (3.23 t ha-1) was obtained in control (To) treatment. Deep tillage favored better root growth and nutrient uptake resulting higher yield of rice.
