Effect of Chemical Fertilizer and Tobacco Stalks-derived Biochar on FCV Tobacco Yield, Nutrient Use Efficiency and Carbon Management Index in a Light Textured Alfisol

Aims: To investigate the effect of tobacco stalk biochar (TS Biochar) and synthetic zeolite (SZ) on light textured sandy loam soil in terms of improving the nutrient use efficiency and productivity of FCV tobacco.

Study Design: Randomized block design (RBD).

Place and Duration of Study: ICAR-CTRI RS, Jeelugumilli, Andhra Pradesh, India.

Methodology: Field experiment was conducted with eight treatments and three replications. The treatments included T1: 100 % NPK; T2: 100% NPK + 1 t ha-1 TS Biochar; T3: 100% NPK + 250 kg ha-1 Synthetic Zeolite (SZ) ; T4: 100 % NPK + 1 t ha-1 TS Biochar + 250 kg ha-1SZ; T5: 100% NPK + 0.5 t ha-1 TS Biomass; T6: Adjusted N & K + 1 t ha-1 TS Biochar; T7: 1 t ha-1 TS Biochar + 250 kg ha-1SZ; T8: Control.TS Biochar was characterized for different functional groups using FTIR analysis

Results: Results revealed that the application of 1 t ha-1 TS Biochar + 100% NPK and 1 t ha-1 TS Biochar +250 kg ha-1 SZ + 100% NPK resulted in a significant increase in tobacco leaf yield compared to the 100% RDF alone . The highest uptake of nitrogen (84.56 kg ha-1) and potassium (122.73 kg ha-1) by tobacco was observed in T2 (100% NPK +1 t ha-1 TS Biochar). Recovery efficiency of N and K applied was greater in tobacco stalk biochar soil amendment with 50.78 and 77.83 per cent as against 100 % NPK alone with 32.83 and 49.64 per cent, respectively. FTIR analysis indicated that TS Biochar is having negative hydroxyl, carbonate and carboxyl functional groups on the surface. Hence, tobacco stalk biochar (TS Biochar) at the rate of 1t ha-1 along with 100% recommended chemical fertilizers can be recommended for the tobacco growing farming community for enhanced yield, nutrient uptake, nutrient use efficiency and soil properties.

Conclusion: Tobacco stalk biochar (TS Biochar) can serve as soil amendment for enhancing nutrient use efficiency in light textured Alfisols.