Evaluating manurial value of bio-slurry for tomato cultivation in sub-tropical floodplain soil

Abstract

Bioslurry is an anaerobically decomposed product, which comes out of the digester after extraction of biogas (chiefly CH₄). Recently a huge amount of bioslurry is being produced in Bangladesh for enormous installation of biogas plants.  Utilization of bioslurry is yet to be addressed adequately though it has potential value as a good quality organic fertilizer. Therefore, a field experiment supported by a laboratory analysis was conducted in floodplain soil of Bangladesh to evaluate the performance of bioslurry along with chemical fertilizers on the yield of tomato (Solanum lycopersicum). The experiment was laid out in a Randomized Complete Block Design (RCBD) with six treatments viz., Control (no fertilizer/manure), N₂₀₀P₉₀K₁₈₀ (100% Recommended Fertilizer Dose, RFD), N₁₂₀P₅₄K₁₀₈ (60% RFD) + Poultry manure (PM), N₁₂₀P₅₄K₁₀₈ (60% RFD) + Poultry slurry, N₁₂₀P₅₄K₁₀₈ (60% RFD) + Cowdung (CD), N₁₂₀P₅₄K₁₀₈ (60% RFD) + Cowdung slurry, each treatment replicated thrice. Chemical analysis of cowdung, cowdung bioslurry, poultry manure and poultry bioslurry showed that the organic carbon, N, P, K and S varied from 10.1-35.1, 0.70-2.52, 0.18- 1.28, 0.86- 3.80 and 0.13- 0.61% respectively. Cowdung and poultry manure had the higher organic carbon content as well as higher nutrient concentration compared to cowdung bioslurry and poultry bioslurry. Nutrient concentration particularly N, P and S in cowdung and cowdung bioslurry was found lower than the poultry manure and poultry bioslurry. The fruit yield of tomato increased by 81-225% due to the application of different slurry, manure and chemical fertilizers compared to no application of manure or fertilizer (control). The highest fruit yield (27.2 t ha^-1) of tomato was obtained from N₁₂₀P₅₄K₁₀₈ + Poultry slurry treatment. Hence application of poultry bioslurry in combination with 60% recommended dose of fertilizers can help improve the production of tomato in sub-tropical floodplain soil.